U8Q8 LIBRARY - DENVER

3 1819 00083042 8

Profwsional Paper Nn. 45 ,

MI

(, . \ B, Descriptive fisnin^y, 75 

I F, Geography, 46 ' ,

/- I'Kl'.VKTMKXT <>K THK INTKHIOU 

\s 

UMTK1> STATES,GKOLOCiICAL SURVEY

CHARLES I'. WAI.ClVVT, I)lRJx:T<)K

T 1 I K

GEOGRAPHY 'AM) GEOLOGY OP ALASKA

A Sl'.MMAHY OF EXISTING KNOWLEDGE

BV

Al.KRKH 11.

WITH A SECTION ON CLIMATE

A TOPOGRAPHIC MA? AND DESCRIITIOX THEKKOF

BY

JA^ 1 ;i : 3 56 * 

LIBRARY

W ASH 1NUTON

\ K K N >f K > T I* H I N T I V O f) F F I C F,

1 !' 0 >
CONTENTS AND ILLUSTRATIONS.

Page.

Introduction.............................-..--....-......_....--............._......--.... 11

Descriptive geography..................................................................... 14

Geographic position and area .......................................................... 14

General geography.................................................................... 15

Coastal features and islands............................................................ 17

General description ......-.-.-.-.-.-..-.-....--.-....-.-._.-...-......_...-.....-. 17

Southern Alaska.................................................................. 18

General features .............................................................. 18

Fiords of southeastern Alaska.................................................. 18

Alexander Archipelago........................................................ 19

Cross Sound to Prince William Sound ..........-.-......._......-.....-........ 20

Cook Inlet ................................................................... 21

Southwestern Alaska.......................--.-.-.-.--....-.....-....._._..... 21

Aleutian Islands .............................................................. 22

Navigation ............................ ...................................... 22

Northern Alaska............-.-..---.-.---.-...-..-.-.-.-.-----.....-..-...-.-.-.. 23

General features.............................................................. 23

Bering Sea coast.............................................................. 23

Arctic Ocean coast........-..-------.-...-.-.-....---.-..----.-.-....-.---.... 25

Navigation ................................................................... 26

Islands....................................................................... 26

Orographic features ................................................................... 27

Introduction ..................................................................... 27

Pacific Mountain system.....-.-.---.------.-.-.-.-.-.-.-.------.---.-.-...-.-.-.-- 28

General relations ............................................................. 28

Coast Range .................................................................. 28

St. Elias Range............................................................... 29

Summary ......-.-.---.-.-........-.-.-...-.-.-......-.-.-.-......... 32

Aleutian Range....._......................................................... 32

Alaska Range................................................................. 33

Central Plateau region ......................................... .................. 36

General features .............................................................. 36

Altitude of plateau ............................................................ 37

Seward Peninsula upland...................................................... 37

Boundary of plateau and mountain ranges ....._.....-.......................... 38

Plateau ranges and mountains ................................................. 38

Coastal plains..........-----.-..-.-.-------.-.-.--------------.-....-.-....... 39

Interior lowlands ...-....--.....-.-.-.-.......-.-........---.-................ 40

Summary .......-.....-.-...-.--------.-.---.-.-.-.------.-.-...-............ 41
4 CONTENTS AND ILLUSTRATIONS.

Descriptive geography Continued.

Orographic features Continued. Page.

Rocky Mountain system........................................................... 42

General description ........................................................... 42

Eastern part.................................................................. 43

Western part................................................................. 44

Summary .................................................................... 45

Arctic Slope region ............................................................... 46

Introduction ................................................................. 46

Subdivisions of province....-....-......._...-._....-.._.-......--.._..-._...._ 46

Summary .................................................................... 47

Drainage .................................... ........................................ 47

Introduction...................................................................... 47

General features .................................................................. 47

Pacific drainage................................................................... 48

Stikine basin ................................................................. 48

Taku basin ................................................................... 49

Chilkat basin................................................................. 50

Small water courses of southeastern Alaska....-....-..-.-..-.-..-.-.--.-....... 51

Cross Sound to Cape Fairweather .............................................. 52

Alsek basin................................................................... 52

Yakutat Bay ................................................................. 54

Copper basin ..............-.-....-.......-.....-..-.----.--.------------..... 54

Copper River to Cook Inlet............-..-.-..-.-.--.-.-..------.--.-......... 57

Sushitna basin................................................................ 57

Matauuska basin......._..-......-.........._.-.-.......-.----..---_----.-.... 58

Summary .................................................................... 58

Bering Sea drainage............................-..-....-.--.-.-..-....-.-....-.-.. 59

Outline ...................................................................... 59

Bristol Bay................................................................... 59

Kuskokwim basin ...-..-...........-...-.....-..-.-..-.----.---.--..-.-.-.... 61

Yukon basin ................................................................. 64

General description .-.-..-....--....-..........-....-..---..--.--..-.-.-.. 64

Lewes Eiver....-..........._...-..._-..-.--.----.----.--.-.-----..-.--.-. 66

Peliy basin............................................................... 68

Subdivisions of the Yukon Valley.......................................... 69

Tipper Yukon and tributaries...................--.--...-.-..-.--.-.-....-. 69

Selwyn River......................................................... 69

White River basin.................................................... 69

Stewart River .......-..-.........-.-..-.-..-.--.-.--.-.-.--.-..-.-.-. 71

Sixtymile Creek ...................................................... 72

Klondike River....................................................... 72

Fortymile basin.... .-....-..-..-.-.-------.----.---.-----..----...... 73

Small tributaries.....-.....-......-.--.----.----.-..-.-..-..---....... 74

Summary ............................................................ 74

Yukon Flats.............................................................. 74

General description .........................-.-..-.-..-.--.----.-..... 74

Porcupine basin .__.__.......-_...-..-.-..-.----.----.-.-------.---... 75

Chandlar basin ..............--.-.--.-..-...-------.--------.---.---.. 76

Birch Creek .......................................................... 76

Hosiana River...........-........-..----.--.--.---------------.-.-.-. 77

Beaver Creek..............-..-........--.-.--.---------..---...-.--.. 77

Dall River.......--.--.-...-..-.-.--..--........-.-..-.-..-...---..... 77

Summary ............................................................ 78

Rampart region........................................................... 78
CONTENTS AND ILLUSTRATIONS. 5

Descriptive geography Continued. 

Drainage Continued.

Bering Sea drainage Continued.

Yukon basin Continued. Page.

Lower Yukon ............................................................ 79

General description. .... 79

Tanana basin .................. 8!!

Tozi River ......................... 88

Nowi River ........................... 88

Melozi River .............................. 88

Koyukuk basin.. ............. 88

Kaltag River......................................... 91

Kaiyuh River .............. 91

Innoko River ............ 91

Anvik River ........... 91

Summary ............ 92

Norton Bound ................. 92

Seward Peninsula ^........................... 92

Arctic drainage.. ..................... 95

Outline .......................................... 96

Hotham Inlet drainage....................... ...... 96

Kotzebue Sound to Point Barrow ..... 100

North Arctic drainage .............. 100

Summary .......................................... 103

History of explorations and surveys. ........................ 104

Introduction.......................................................................... 104

Geography as related to development................................................. 104

Main features of history .............................................................. 105

Early Russian explorations ........................................................... 105

Exploration of rival nationalities...................................................... 109

Russian occupation ................................................................... 113

American occupation.................................................................. 119

Conclusion .......................................................................... 132

Climate, by Cleveland Abbe, jr.......................................................... 133

Introduction.......................................................................... 133

Meteorologio observation;;............ 133

Sources of material................................................................... 134

Methods of observation............................................................... 134

Temperature...................................................................... 184

Precipitation ........................................................J............ 135

Frost and ice..................................................................... 137

Description of the synoptic tables ...................................................... 137

List of stations with locations..................................... 138

Extreme temperatures ............................................ 139

Precipitation ..................................................... 139

Heavy rainfalls............................. ..................... 139

Rainy days....................................................... 139

Dates of frosts.................................................... 139

Stream and harbor ice............................................ 140

Climatic provinces of Alaska.......................................................... 140

Pacific coast...................................................... 140

Alaska Peninsula................................................. 140

Aleutian Islands.................................................. 141

Bering Sea coast. .J.. ....................................... 141

Bering Sea islands................................................ 14]

Arctic coast...................................................... ]41
6 CONTENTS AND ILLTJSTBATIONS.

Climate, by Cleveland Abbe, jr. Continued.

Climatic provinces of Alaska Continued. page.

Interior.......................................................... HI

Copper Kiver plateau............................................. 141

General climatology of Alaska ........................................................ 144

Climatic features, by provinces .......... ............................................. 148

Pacific coast climatic province ---.------......---.---.------.---..-..---....-..--. 148

Rainfall.......................................................... 148

Temperature...................................................... 149

Growing season .--.-._......--.-.-.................-......-...... 149

River and harbor ice............................................. 149

Alaska Peninsula climatic province................................................ 150

Rainfall.......................................................... 150

Temperature...................................................... 150

Growing season -.-.......-.-.-.-...-..-.-.-..................-... 150

River and harbor ice............................................. 151

Aleutian Islands climatic province ................................................ 151

Rainfall.......................................................... 151

Temperature..-...-...........-.-........----..................... 151

Growing season ......_.........-.._...................._......... 151

River and harbor ice ............................................. 152

Bering Sea coast and islands climatic province .................................... 152

Rainfall .......................................................... 152

Temperature-..-.-.-..........-..-.--.--..-.-.-.-................. 153

Frosts............................................................ 153

Sea ice........................................................... 153

Arctic coast climatic province....................................................... 153

Rainfall.......................................................... 153

Temperature .-.-..-.........-..-.-...-...---........-......--.-.- 154

Frosts............................................................ 154

Interior climatic province .........,-.........-.--... .--.-.---...............-..... 154

Temperature...................................................... 154

Growing season -.-.-.......---.-.-....--.-..--.-...--.-....-.-.-.. 155

Rainfall .......................................................... 156

River ice ......................................................... 157

General climatologic tables ... ................._-.-.-....-.-..-.....................- 157

Special climatologic tables............................................................. 177

Object .......................-..-..-........---.-..-.-.-----....-......-....-.-.. 177

Scheitelwerte.......-.-......-.-.---..-...-..-.--.-.-.--.-----.---..-.---.--.---.. 177

Manner of constructing the tables...-......-.-.--.-....----.-.-.-.-..-...-....-.-.- 177

Use of the tables.................................................................. 178

Discussion of the frequency tables for Killisnoo..................................... 178

Frequencies of maximum temperature.....---......-.-..---.............-...-.. 179

Frequencies of minimum temperature.......................................... 183

Frequencies of rainy days ..--.-..........-.---------.-----.-..-.---......-.... 183

Frequency tables for Sitka..--..-.............---..-.-.--.----.......-.-........... 185

Frequencies of rainy days...................................................... 185

Frequency tables for Coal Harbor.................................................. 186

Rainfall at Alaska stations ......................................................... 188

Geology.........---.--.-.--.-.-....-.----.-.---..------.--------.-----.------.---------.. 200

Introduction ..-.....-..-....-.-.--.---....-.-.--------.-..------.------....--.-..---. 200

Correlation with western United States and Canada ..................................... 203

Geologic reconnaissance map.......-..............----.--.-..----......--.--.-.......-. 204

Correlations .........-...-...-......-..-...-.-..--.-.--..-..-.-..-...---.-....-..--.-. 206

Stratigraphic succession ............................................................... 208

Outline.......................................................................... 208
CONTENTS AJSD ILLUSTRATIONS. 7

Geology Continued.

Stratigraphic succession Continued. Page.

Pre-Paleozoic..................................................................... 208

Archean........... __...._......................_...___....................... 208

Paleozoic......................................................................... 210

General statement............................................................. 210

Lower Paleozoic ---.-----..--------..-.-._--....--.....--...-.......--...--... 211

Devonian...--....-....-...-.................,............--....-...---.---... 218

Carboniferous .---..----....--.----..............-..-..-..---..-..-.-...---.., 221

Mesozoic......................................................................... 225

General statement............................................................. 225

Triassic and Jurassic .......................................................... 226

Cretaceous........-.........--....-....-..................---...--...--..--... 234

Cenozoic ........-...--..---..----.----...-....--............---.-.---.---...----. 237

Tertiary...................................................................... 237

Eocene............................................................... 238

Miocene and Pliocene ................................................. 242

Summary of Tertiary stratigraphy.......... ......-----.-.--............ 243

Quaternary..-.........-...--.....-...--...--....-...--.-----..-.-.-.--.---.-. 244

Present glaciers....................................................... 244

Former glaciation............'...................-.----..---------.---. 245

Pleistocene sediments ..----....-.................----....-..--....--.. 248

Recent deposits ....................................................... 249

Igneous rocks...--....-...--...-.-..............-...........-.--....--....-....-.. 249

Intnisives --.-. -..--.--.---------....--..-.-........_..---...--...-.....--... 249

VolcanifS..................................................................... 250

Summary of stratigraphic succession................................................ 251

Structure............................................................................. 252

Introduction...................................................................... 252

Pacific Mountain system........................................................... 253

Central Plateau region............................................................. 258

Rocky Mountain system........................................................... 259

Geologic history .....-....-..-.-...--..---..---...............-.-.-................... 263

Geoniorphology......-....-.--.-....-.----...--...---....-....-.----.................. 267

Introduction...................................................................... 267

Topography ...................................................................... 267

Genetic classification of topographic types .......................................... 269

General statement ............................................................ 269

Mountains..-....-....--..-.-.-.--..---....-....--........--.................. 269

General types......................................................... 269

Mountains of recent uplift............................................. 269

Volcanic mountain ranges ............................................. 275

Residual mountains ................................................... 275

Plateaus...................................................................... 276

General types......................................................... 276

Plateaus of the dissected peneplain type ................................ 276

Constructional plateaus----....---......-...----.-.-------............. 280

Lowlands .................................................................... 281

Coastal plains............. ........................................... 281

Basin lowlands........................................................ 281

Lakes ........................................................................ 283

Coastal features--.----.------.---...--...---...-........-..................... 283

Drainage ..................................................................... 284
8 CONTENTS AND ILLUSTRATIONS.

Geology Continued.

Geomorphology Continued. Page.

Correlation of peneplains .......................................................... 286

Introduction.................................................................. 286

Peneplains ................................................................... 286

Correlation................................................................... 288

Recent geologic history............................................................ 290

Introduction......_............................................................ 290

Conditions anterior to Upper Cretaceous time.----..-...--.---....--------..---- 29]

Late Cretaceous and early Eocene deposition.............----.....-.-.......-... 291

Uplift and planation (late Eocene or Miocene) -..........-----.....-..-.....-... 292

Differential elevation and erosion............................................... 294

Influence of Glacial epoch on topography............_.......................... 295

Description of topographic map of Alaska, by R. U. Goode ........._........................ 296

Publications on Alaska and adjacent regions ..........................................!..... 298

Index.................................................................................... 309

PLATE I. Relief model of Alaska, by E. E. Howell, from base map by United States Geological

Survey -.......-.........-..-..........-......-----.....--------..---.......-.. 11

II. Geographic provinces of northwestern North America -.........--.....---.......... 16

III. Typical shore topography of southern Alaska, Gastineau Channel, and Taku Inlet ... 18

IV. A, View down Gastineau Channel from Mount Juneau, showing typical shore topography of southern Alaska; B, Hunter Bay, Prince of Wales Island, illustrating 

deep-water conditions close to land ...............-.-....-----..-..-----.....-.- 20

V. Gastineau Channel and Juneau, showing abrupt slope from tide water...----.....-.. 22

VI. Western end of Seward Peninsula, showing typical shore topography of northern

Alaska, also York Plateau...................................................... 24

VII. Geographic provinces and mountain axes of Alaska ................................ 28

VIII. A, Mount St. Elias from the south; B, Mount McKinley from the northwest......_.. 30

IX. A, Mount Wrangell, an active volcano; B, Mount Drum, Copper River region, a dissected crater................................................................... 32

X. A, Mount Augustine, Cook Inlet, a typical ash cone; B, Inland front of St. Elias

Range, White River basin, showing abrupt transition to the plateau............... 34

XI. Topographic map of Mount McKinley region. ..................................... 36

XII. Map showing distribution of forests and glaciers ................................... 38

XIII. The upland of Seward Peninsula near Hot Springs ................................. 40

XIV. A, Northern margin of Yukon Flats in Chandlar Valley; B, Northern margin of

Copper River Plateau .......................................................... 42

XV. A, View up Matanuska Valley from Glacier Point, showing recent gorge in older

valley; B, Yukon Valley at Dawson............................................. 58

XVI. A, Yukon Valley in Ramparts, showing abrupt slope of valley wall from water;

B, Yukon Valley at Eagle...................................................... 78

XVII. A, Valley of Fox River, typical topography in Seward Peninsula; B, Valley of Fortymile River near the boundary........--........-........---.-.--...-.-......-.. 92

XVIII. Map showing meteorologic stations- ...... ....................................... 136

XIX. Typical monthly rainfalls ........................................................ 148

XX. Geologic sketch map of northwestern North America.............................. 202

XXI. Geologic reconnaissance map of Alaska ...-....-..-.....................----.-..-.. 204

XXII. Sketch map of glacial geology of Alaska ........................................... 244

XXIII. A, Oconnor Glacier from Slims River Valley, a typical valley glacier on the north 

slope of the St. Elias Range; B, Dalton Glacier, Disenchantment Bay, a typical 

tide-water glacier from south slope of St. Elias Range..-......-.----.--..-.._.___. 246
CONTENTS AND ILLUSTRATIONS. »

Page. 

PLATE XXIV. A, Glaciation in upper John River Valley, in Endicott Mountains; B, Ice

remnants of John River Valley Glacier .................................... 248

XXV. A, Eastern margin Copper River Plateau, showing silt deposits; B, Lewes

Valley at White Horse, showing silt terraces ............................... 250

XXVI. A, White Horse Rapids of the Lewes, caused by recent lava flow; B, Miles

Canyon at the Lewes River, cut in a recent lava flow ..-..--...-.-._........ 252

XXVII. Diagrammatic geologic structure sections .._-_..._.-.....---..--.-.--.--.._-.- 254

XXVIII. A, Summits of Coast Range from point near Juneau, showing dissected plateau 

feature; -B, Summits of Chugach Mountains, showing dissected plateau 

feature...........-.--.....-..-..--------.--..-..-.--.--------.-----...-.. 256

XXIX. A, Summits of Endicott Mountains (Rocky Mountain system], showing dissected plateau feature; B, North front of Endicott Mountains, showing relations to Anaktuvuk Plateau and planated surface of plateau.................. 260

XXX. A, Wave-cut rock bench at north side of Port Clarence, Seward Peninsula; 

B, Yukon Plateau from altitude of about 5,000 feet at north base of Nutzotin 

Mountains ...-..--.--...........-.--.-...-..-.....-..........-.--.-...... 276

XXXI. Wave-cut rock bench oil south side of King River Valley, Seward Peninsula.-.- 278

XXXII. A, Gravel plateau at uorthwest base of Alaska Range; B, View across Donjek

River, abandoned valley in middle distance --..-.--.-..--..-..----......... 280

XXXIII. A, Upper Niukluk basin, Seward Peninsula, a typical basin lowland; B, Lower

gorge of Kobuk, draining a basin lowland .--..-----.--.-..--......-.._..... 282

XXXIV. Topographic map of Alaska................................................ Pocket '

FIG. 1. Map of the world, showing geographic position of Alaska............................ 14

2. Map showing the relative size of Alaska and United States............................ 15

3. Map showing areas surveyed and explored by United States Geological Survey, 1898 to

1903 ........................................................................... 131

4. York Plateau..................................................................... 280

5. Upper basin of the Fish River, Seward Peninsula, a typical basin lowland ............ 282

6. Sketch map, showing former drainage courses -............-.--.-----.----.......... 285
U. S. GEOLOGICAl SURVEY PROFESSIONAL PAPER NO. 45 PL. 1

RELIEF MODEL OF ALASKA. 

By E E, Howell, from base map by U. S, Geological Survey.
GEOGRAPHY AND GEOLOGY OF ALASKA.

By ALFRED H. BROOKS.

INTRODUCTION.

Alaska, the largest outlying possession of the United States, is that great land 

mass forming the northwestern extremity of the North American continent, whose 

western point is within 60 miles of the Asiatic coast (PI. II). About one-quarter of 

this area lies within the Arctic Circle, and from the standpoint of geographic position 

must be regarded as an arctic province; but the southern seaboard, exposed to the 

warm winds and waters of the Pacific, gives to the entire southern portion of the 

territory" a comparatively warm climate. It is not generally realized that the range 

of climate in Alaska is greater than that between Florida and Maine. At the southernmost point of the Pacific coast the mean annual temperature is not far from that 

of the city of Washington, the winters being warmer and characterized b}r less snowfall; the Yukon Valley on the other hand has a winter climate similar to that of 

northern Montana and Dakota; while in the extreme northern part of the territory 

the meteorologic conditions are invariabty arctic.

Though as yet only sparsely settled, Alaska's vast area and great resources 

make it one of the most important possessions of the United States and promise its 

rapid development. During the years 1890 to 1900 the population increased from 

32,052* to 63,592. The mineral output, which in 1890 was valued at less than 

$800,000, exceeded $9,000,000 in 1904, and the fisheries show a corresponding 

growth. This rapid development has attracted public attention and led to urgent 

demand for explorations, surveys, and other investigations. So actively has this 

work been pushed, both by public and private enterprise, that exact knowledge of 

the geography, geology, and mineral resources of the interior has made greater 

strides within the last eight years than during the preceding thirty-one years 

since the acquisition of Alaska. The facts regarding the geography and geology, 

scattered as they are through the many books and reports of this period, are not 

always readily accessible, and the time seems ripe to present them in a summarized 

form.

The topography of Alaska is varied and complex (see PI. I), and it is not easy 

to present briefly even the salient features. The limited number of pages here

a While Alaska Is usually designated a " Territory," legally it is an unorganized territory, district, or colony, as it has 

not a Territorial form of government. 

6 Twelfth Census, 1900, vol. 1, p. 47.
12 GEOGRAPHY AND GEOLOGY OF ALASKA.

devoted to the subject precludes the possibility of detailed treatment, even if the 

facts were available. Much of the description has been taken from the results 

attained by other investigators, the writer being personally familiar with only a 

part of this large province. A list of the publications consulted is appended.

The larger geographic features of Alaska are now fairly well known, though 

the detailed surveys which are demanded by the development of many localities 

have hardly been begun. Preliminary surveys have been completed of all but 

three 8 of the larger rivers. The most important mountain ranges have been at 

least outlined (fig. 3). Only three large areas remain almost entirely unmapped: 

One in southwestern Alaska, between Cook Inlet and the lower Kuskokwim, and 

the others in northern Alaska, embracing the Arctic watershed east and west 

of the Colville River. Nearly all the surveys of the interior, however, have been 

of a preliminary and exploratory character, and to meet the requirements of exact 

geography must be followed by more detailed mensuration.

Though the coast line has been fairly well known for more than half a 

century, knowledge of the interior has been gained chiefly within the last two 

decades. This has not yet found its way into text-books and has too often been 

entirely ignored by cartographers. If facts are presented which may seem 

elementary, it is because even well-informed people have been known to harbor 

misconceptions in regard to the orographic features, climate, and general character 

of Alaska. Those who read of the perils and privations of winter travel and 

explorations are apt to picture a region of ice and snow; others, again, who have 

personal knowledge of the tourist route of southeastern Alaska, regard the whole 

district as one of rugged mountains and glaciers. In point of fact, glaciers are 

now nearly limited to the ranges bordering the Pacific and to the two slopes of 

the Alaska range; and even during the greatest development of glaciers but a 

small portion of Alaska was under ice (see map, PI. XXII).

As a treatise on geography would hardly be complete without some discussion 

of the climate, meteorologic data have been compiled by Mr. Cleveland Abbe, jr., 

but the discussion of this does not pretend to be more than a cursory treatment 

of the subject.

The scope of the paper seems to require also a brief summary of the development of geographic knowledge of Alaska. This subject, with its many ramifications, 

is of fascinating interest and offers a magnificent field for the trained historian. If 

the accompanying sketch of discovery and exploration awakens any measure of 

popular interest the writer will feel amply rewarded for having attacked a theme 

which hardly falls within the scope of his investigations.

When this compilation was begun it was intended to be chiefly a description 

of the topography of Alaska, as illustrated by the accompanying map (PI. XXXIV, 

in pocket), which was compiled under the direction of the late R. U. Goode. In 

the course of the work there accumulated much geologic as well as geographic 

material which seemed worthy of inclusion in the report. As no comprehensive 

statement of the geology of Alaska has been made since the modern epoch of 

investigation was begun, an attempt will be made to give a summary of all results 

achieved. Since the writer has obtained much of his knowledge of the facts from

a The Noatak, Alwek, and upper Colville. The lower Colville has been mapped. Some large tributaries of the Kuskokwim and the lower Yukon are also unsurveyed.
INTRODUCTION. 13

the work of others, he disclaims any pretense of making an entirely original 

contribution to geologic science. He feels, however, that a personal familiarity 

with a considerable part of the province, gained during seven consecutive seasons 

of field work, will justify Mm in presenting conclusions which may in some cases 

be at variance with those in the reports on which he must draw for his facts.

Throughout this report attempt will be made to credit borrowed material to 

the source from which it is drawn. Where such matter has been obtained 

entirely from published reports there is no difficulty in so doing; but as regards 

investigators of the Geological Survey, with whom the writer has collaborated 

both in field and in office, the case is somewhat different, for it is not always 

possible to know whether this or that theory originated with the writer or with 

one of his colleagues. It will, then, perhaps suffice to state that this report 

could not have been prepared without the explorations and researches of the 

geologists, F. C. Schrader, Walter C. Mendenhall, Arthur J. Collier, J. E. Spurr, 

and Arthur C. Spencer; and the surveys of the topographers, T. G. Gerdine, 

D. C. Witherspoon, D. L. Reaburn, W. J. Peters, and E. C. Barnard. Each 

of these men, in the course of from two to six years of field work, has made 

important contributions to the knowledge of the geography and geology of 

Alaska, and not all of these results have yet been put in print. In the last 

season (1903) L. M. Prindle, C. W. Wright, Arthur Hollick, G. C. Martin, 

F. L. Hess, and Fred H. Moffit have carried on geologic work in Alaska, and 

the writer has made use of their work now in course of publication. He has 

also been fortunate in having access to the manuscript reports of Walter C. 

Mendenhall and F. C. Schrader on the Copper River basin, to which references 

will be made. The matter here presented should be credited in a measure to 

all of these investigators, but for many of the theories advanced the writer 

alone is responsible.

As this manuscript goes to press there has been opportunity to incorporate 

some of the results of the field work of 1904. As far as possible these have 

been embodied in the text, but in some instances it has been found advisable to 

add them only as footnotes. During the past summer F. E. and C. W. Wright 

extended the geologic reconnaissance in southeastern Alaska. In southwestern 

Alaska G. C. Martin and T. W. Stanton have determined the general Mesozoic 

section, while F. H. Moffit has made a reconnaissance of the northern part of 

the Kenai Peninsula. A. J. Collier has mapped the geology of the Cape 

Lisburne region, and L. M. Prindle and F. L. Hess have made contributions to 

the knowledge of the metamorphic terranes of the Yukon-Tanana district.

It is the writer's purpose to describe in nontechnical language the larger 

geographic features and discuss their relation as far as the data available will 

permit. In the treatment of the geology, however, less effort will be made to 

make the matter acceptable to the lay reader. It is hoped, however, that a 

brief summary of the salient features of the geologic history' may be not without 

interest to the general public. If this paper serves in some measure to dispel 

the popular fallacies regarding Alaska and to disseminate more accurate 

knowledge of its geographic and geologic features, the purpose of its publication 

will be accomplished.
14 GEOGRAPHY AND GEOLOGY OF ALASKA.

DESCRIPTIVE GEOGRAPHY.

GEOGRAPHIC POSITION AND AREA.

Alaska in its greatest extent is included between the meridians of 130° west 

longitude and 173° east longitude, and between the parallels of 51° and 72° north 

latitude. It is bounded on the north by the Arctic Ocean, on the west by the Arctic 

Ocean; Bering Strait, and Bering Sea, on the south and southwest by the Gulf of

170- 180" 168° 150' Ul° 60" 30°

160- T70" ISO" 188' IWU1- 120°

FIG. 1. Map of the world, showing geographic position of Alaska.

Alaska and the Pacific Ocean, and on the east by the Yukon Territory and British 

Columbia. The eastern boundary from the Arctic Ocean to the neighborhood of 

Mount St. Elias is the one hundred and forty-first meridian; thence southeastward 

to Portland Canal it is irregrilar and can not be described in general terms.

The geographic position of Alaska is shown on the accompanying chart of the 

world (fig. 1). It is in approximately the same latitude as the Scandinavian Peninsula; Point Barrow, its northernmost point, is in about the same latitude as North 

Cape; Dixon Entrance, which marks its southern boundary, is nearly on the same 

parallel as Copenhagen; St. Elias is in the latitude of Christiania and St. Petersburg; and Sitka, the capital of Alaska, is in the latitude of Edinburgh. The longitude of the western terminal of the Aleutian Islands is almost identical with that 

of the New Hebrides Islands and is the same as that of New Zealand, and Cape 

Prince of Wales, the most westerly point of the mainland, is nearly as far west 

as the Samoan Islands. Thus a person traveling from New York to Attu Island,
GENEKAL GEOGRAPHY. 15

the westernmost of the Aleutian chain, on reaching San Francisco will have 

accomplished less than half the journey from east to west.

The area of Alaska is about 586,400 square miles, one-fifth that of the United 

States. The popular conception of the size of Alaska is based on maps of North 

America, which always distort it. Fig. a, which shows Alaska superimposed on 

a map of the United States of the same scale, demonstrates that the distance 

from the easternmost to the westernmost point in Alaska is equal to the distance 

from the Atlantic to the Pacific in the latitude of Los Angeles, and that its

129° lgfi° 181° 117° 113" 109° 105° 101° 97° 03° 85° 81° 77' 78' 68° 65'

117° 118° 109° 105°_____ 101° ___67" BB- 81° 77"

FIG. 2. Map showing the relative size of Alaska and the United States.

northernmost and southernmost points are nearly as far apart as the Mexican and 

the Canadian boundaries of the United States. 

t

GENERAL GEOGRAPHY.

The main mass of Alaska is nearly rectangular and is carved out from the

continent by Mackenzie Bay on the north and the Gulf of Alaska on the south (see

PI. 1). An extension to the southeast is furnished by the so-called panhandle of

southeastern Alaska, and to the southwest by the Alaska Peninsula and the Aleutian

 Islands.

Alaska has three peninsulas of considerable size (PL XXXIV). The Alaska 

Peninsula stretches to the southwest, and with the archipelagoes beyond the Aleutian Islands belonging to Alaska and the Commander Islands belonging to Eussia 

. forms a broken barrier between Bering Sea and the Pacific Ocean. The Kenai 

Peninsula, which is much smaller than the Alaska Peninsula and lies farther east,

\
16 GEOGRAPHY AND GEOLOGY OF ALASKA.

is separated from the mainland by Cook Inlet on the west and Prince William 

. Sound on the east, with Kodiak and the adjacent islands forming- an extension to 

the southwest. The Seward Peninsula, whose extremity marks the westernmost 

point of the continent, extends from the central part of Alaska and is bounded 

on the north by Kotzebue Sound and the Arctic Ocean, and on the south by 

Norton Sound and Bering Sea. The Seward Peninsula and the Chuckchee Peninsula of Siberia, which are separated by Bering- Strait, 60 miles in width, divide 

Bering Sea from the Arctic Ocean.

Around the Gulf of Alaska the Pacific coast line forms a deep reentering 

angle, the eastern leg of which borders the panhandle of the territory usually 

called southeastern Alaska, while the western leg is the shore line of the Alaska 

Peninsula. The axes of the dominant mountain ranges (Pis. I and VII) also undergo 

a marked change in direction, parallel to this crescentlike bend of the southern 

coast line (see p. 287). This bend is, indeed, the topographic record of an important structural feature.

The main topographic features of Alaska are similar to those of the western 

United States. The highlands of Alaska, like those of the United States and 

Canada, are in general parallel to the coast line, and the investigations of Doctor 

Dawson" and others have shown that the four topographic provinces of the United 

States are fairly well defined throughout western Canada and continue into Alaska. 

A broad, mountainous belt, designated by Major PowelP the Pacific Mountains, 

but here referred to as the Pacific Mountain system, including the Coast Ranges of 

California, Oregon, and Washington, the Sierra Nevada and the Cascade Range, 

extends along the western margin of the United States and continues northward 

into Canada. East of this lies the Central Plateau region, or Great Basin, as it is 

usually called. This is essentially a high plateau belt, though it contains mountain 

ranges, and it, too, finds its northern counterpart in British Columbia. The eastern 

limit of this plateau region is marked by a number of parallel ranges, grouped 

together under the name c Rocky Mountain system, which also, like the Pacific 

Mountain system, extend into Canada. To the east of the Rocky Mountain system are the Great Plains, which stretch northward to the Arctic Ocean. The 

lines of demarcation between these provinces are usually sharply drawn. Each is 

of a dominant topographic type, though each exhibits many minor topographic 

subdivisions.

Along the Pacific coast, of Alaska and British Columbia is a mountainous 

belt 50 to 200 miles in width, which is the westernmost of the four provinces, 

and may be designated the ''Pacific Mountain system." It properly includes the 

mountainous Alexander Archipelago and Aleutian Islands, as well as a number of 

other island groups. While this region is in the main rugged and mountainous, 

its ranges are distinct and often separated by broad valleys or indentations of 

the coast line, forming in several cases large basins, like that of the Copper 

River. Except for a section of the inner slope, which drains into the Yukon

aDawson, G. M., On the later physiographical geology of the Rocky Mountain region in Canada: Trails. Royal Soc. 

Canada, vol. 8, sec. 4, 1890.

Geological record in the Rocky Mountain region in Canada: Bull. Geol. Soc. America, vol. 12, 1901, pp. 57-92. 

bPowell, J. W., Physiographic regions of the United States: Nat. Geog. Soc., Mon. I, pp. 96-100. 

c Major Powell terms these the Stony Mountains, op. cit., p. 100.
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 45 PL. II

176° 180°______175'_____170°_____165' . 160° 165° 150° 145°___140°__136° 130° 135° 120° 115° 110° 106'

GEOGRAPHIC PROVINCES

NORTHWESTERN NORTH

BY ALFRED H. BROOKS,

165- 150° longitude 145' West 140' from 135"° Greenwich 130° 115°
COASTAL FEATURES AND ISLANDS. 17

and Kuskokwim, its waters reach the Pacific through streams flowing transverse 

to the axis of the mountains.

East and north of the Pacific Mountains is the Central Plateau region, corresponding in a broad way with the Central Plateau of the western United States and 

Canada. The term "plateau" can be assigned to only a portion of this province, 

and even that is not a plateau in strict sense. For the most part this region 

is a gently rolling upland, in which the rivers have trenched broad channels, 

and which is of low relief compared with the adjacent mountain ranges (PI. 

XXX, li). The interstream areas are the remnants of a former plateau surface, 

which has been dissected by erosion, and whose rolling surface slopes gently to 

the north and west. The continuity of this plateau is broken by a number of 

mountains and mountain groups which rise above the general level, but these 

are of much less extent and relief than the similar features of the plateau region of 

the western United States and Canada. This belt is drained largely by the Yukon 

and Kuskokwim rivers into Bering Sea, and includes a number of lowland areas 

of considerable extent. Among these the flats of the middle Yukon and upper 

Kuskokwim and the lowlands which extend along Bering Soa adjacent to the deltas 

of the Kuskokwim and Yukon are notable.

East and north of the plateau province a broad cordillora forms the third of 

the geographic divisions, and is the northern extension of the Rocky Mountain 

system (PI. II). The ranges of this division, like those of the Pacific Mountain 

system, also undergo a marked change in direction. As in the United States, they 

trend northwestward, but swing to the southwest at the Arctic shore, which they 

touch again north of Bering Strait. The drainage of the southern slopes of the 

mountains is chiefly tributary to the Yukon, while the northern slope drains into 

the Arctic Ocean.

The Great Plains east and north of the Rockies form the fourth province. 

In Alaska this province is represented by an area of low relief which lies 

between the western extension of the Rocky Mountains and the Arctic Ocean and 

is designated the "Arctic slope region." This area, like the corresponding one in 

the western United States, is really a slightly elevated plateau, which slopes to 

the north from the foothills of the Rocky Mountains (PI. XXIX, B). It is 

dissected and more or less rolling, and its waters flow northward into the Arctic 

Ocean.

COASTAL FEATURES AND ISLANDS.

GENERAL DESCRIPTION.

Alaska's shores are washed by three great oceans the Arctic on the north 

and northwest, Bering Sea on the west, and the Pacific on the south (Pis. VII and 

XXXIV). The northern Pacific is deep, and the coastal shelf bordering it is, as a 

rule, very narrow. Similar conditions prevail in the southwestern part of Bering 

Sea adjacent to the Aleutian Islands, which are elevated points on a narrow submarine ridge between the Bering Sea and the northern Pacific, and from which the 

coastal shelf sinks abruptlj- toward the west. On the other hand, that part of 

the Bering Sea adjacent to the mainland is shoal. The 100-fathom line enters the
18 GEOGRAPHY AND GEOLOGY OF ALASKA.

Bering Sea near the eastern end of the Aleutian Islands and turns to the northwest, passing south of St. Matthew Island in the direction of the Siberian coast. 

As far as can be determined from the small number of soundings, this shoal 

continues along the Arctic coast, 30 or 40 fathoms being the limit of depth 

discovered (see PI. I).

Thus, two distinct types of coastal topography are recognizable. Along the 

Pacific Ocean and the southern portion of Bering Sea the shores are rocky and 

abrupt, broken by countless indentations, and bordered by deep water close in to 

the land (see Pis. Ill, IV, A, and IV, J3). In complete contrast are the coastal 

features of northern Alaska, where the Arctic Ocean and most of the Bering Sea 

are characterized by shoal water for a long distance from land, and by a low shore 

line with many straight, long, unbroken beaches (Pis. VI and XXX, A). While 

the southern coast, with its abrupt cliffs, towering snow peaks, and deep tidal 

waterways, offers an infinitely varied scenery hardly paralleled, the shores of 

Bering Sea and the Arctic Ocean, with their long stretches of sandy beach and flat 

exposure of treeless plains, are monotonous in the extreme.

SOUTHERN ALASKA. 

GENERAL FEATUKES.

East and south of Bristol Bay and the Alaska Peninsula the shore topography 

is characterized by great irregularity; deep embaymeuts penetrate the mainland, 

and many islands are separated by a network of rocky straits. From the narrow 

coastal shelf the sea bottom descends very rapidly to great depths, and the land rises 

steeply from tide water. The limit of wave action is usually marked by a rock 

bench or a narrow rocky beach, which is terminated inland by a cliff. This type of 

shore topography is well shown on the accompanying map (PI. Ill) and photographs 

(Pis. IV, A and J3, and V) of Gastineau Channel. It is characteristic of the whole 

Pacific coastal belt, including the Aleutian Islands, except the shores of Cook Inlet 

and a stretch of about 200 miles in the St. Elias region between Lituya Bay and the 

western limit of the Copper River delta, where the shore line is even and the 

land rises gently inland.

FIORDS OF SOUTHEASTERN ALASKA.

The southern coast of Alaska has the shape of a broad crescent which opens 

out to the Pacific Ocean. The southeastern horn of this crescent includes the 

Alexander Archipelago and its scores of islands, great and small, penetrated and 

separated by an intricate system of tidal waterways, some of which extend far inland 

and give the coast the fiord character which has made its scenery famous the world 

over. These channels (see PI. XXXIV, in pocket) fall into two general systems. 

of which one trends approximately north and south, and the other about N. 70° W., 

though there are many variations from these courses. The largest of the fiords 

which penetrate the mainland are Glacier Bay and Lynn and Portland canals.

Glacier Bay stretches about 60 miles northward from Icy Strait. Its shores 

are broken by numerous embaymeuts, fed by tide-water glaciers. The bay splits 

the southern end of the St. Elias Range into two parts, the southernmost of which
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 45 PL. Ill

TYPICAL SHORE TOPOGRAPHY OF SOUTHERN ALASKA, GASTINEAU 

BY iHnRHmoHM. CHANNEL, AND TAKU INLET.

BOUNDARY 8UKM , , , ^ Scale K

10 Vniles

1904
COASTAL FEATURES AND ISLANDS. 19

is known as the Fairweather Mountains. Forty miles east of Glacier Bay the mainland and the archipelago are cleft by a remarkably straight waterway known as 

Chatham Strait and Lynn Canal. This fiord extends nearly 175 miles from the 

open ocean, forking at its upper end into two branches, the western called Chilkoot 

and the eastern Taiya Inlet. For many miles the shores of Lynn Canal are bounded 

by steep rock Avails, which often rise sheer from the water, and at its head the peaks 

of the Coast Range reach a height of 8,000 and 9,000 feet above the sea.

Portland Canal, which marks the southeastern boundary of Alaska, is a narrow 

waterway extending about 100 miles inland from Dixon Entrance. Unlike most of 

the other fiords, it is characterized by a number of large bends, but its general 

direction is northerly. Along its course, which lies chiefly through the Coast 

Range, the relief is between 5,000 and 6,000 feet.

In these fiords the sea bottom usually falls off abruptly close to land, often 

reaching a depth of 60 or 70 fathoms within a few yards (PI. IV, 7?). The deepest 

soundings thus far made in these inland waterways register 300 to 400 fathoms, and 

depths of 100 to 200 fathoms are not uncommon. It is further evident that the 

contour of the ocean floor is often of a basinlike character.

The fiords which penetrate the mainland receive numerous glaciers from the 

large neve fields of the Coast and St. Elias ranges. Those of Glacier Bay are best 

known because they are each year visited by many tourists. Besides the tide-water 

glaciers, there are many others discharging into the tributaries of the channels.

ALEXANDER ARCHIPELAGO.

The largest islands of the Alexander Archipelago, beginning at the north, are 

Chichagof, Baranof, Admiralty, Kupreanof, Kuiu, Prince of Wales, Etolin, and 

Revillagigedo. The longer axis of nearly all these has a northwest-southeast 

direction, and they all possess strong relief, bold coast, and irregular shore lines. 

Chichagof and Baranof, in the northern end of the archipelago, are cut off from the 

mainland by Cross Sound and Icy Strait, and from the islands on the east by 

Chatham Strait. Together they form a wedge-shaped land mass which is split into 

two islands by Peril Strait, a winding waterway whose hidden rocks and strong 

tidal currents give it its well-merited name. The islands are mountainous, with a 

relief of 3,000 to 5,000 feet, and their axis is in line with the axis of the St. Elias 

Range to the northwest. Kruzof, a small island adjacent to Baranof on the west, is 

of interest because it contains Mount Edgecumbe, the only volcano of southeastern 

Alaska.

Admiralty Island, east of the two above described, is long and narrow, with 

rugged highlands, which may also be considered a southern extension of the St. Elias 

Range. On the east Stephens Passage separates it from the mainland, and on the 

south Frederick Sound divides it from a group of islands, the largest of which are 

Kupreanof and Kuiu. These two have less relief and are especially characterized 

by great irregularity of shore line. In fact, the many channels and embayments 

which cut into Kuiu Island give it the form of a dendritic land mass. Mitkof Island 

lies southeast of Kupreanof, from which it is separated by Wrangell Narrows, next 

to Peril Strait the most dangerous of the passages used by vessels.
20 GEOGRAPHY AND GEOLOGY OF ALASKA.

South of Sumrier Strait the Alexander Archipelago is divided by Clarence 

Strait into the Prince of Wales group on the west and the Revillagigedo group 

on the east. Prince of Wales Island," the largest of the archipelago, is about MO 

miles long and 40 miles wide. Its coast line is broken by many deep embayments, 

and where these lie opposite each other the width of the island is reduced to but 

a few miles. These opposing fiords are, in some instances, connected by broad 

depressions, with low divides. The relief of the island varies from 1,500 to 3,600 

feet. The mountains, the highest of which reach an altitude of 3,600 feet, form no 

well-defined ranges, but have a general northwest-southeast linear arrangement.

In topographic relief and geographic position the Revillagigedo group of 

islands properly forms a part of that irregular mountain mass known as the Coast 

Range; their highlands have the same general trend and reach an altitude of 3,300 

feet.

The traveler who threads his way among the waterways of the Alexander 

Archipelago will gain the impression that the region is one of strong relief, with 

practically no lowlands or flat valley floors; but this is true only in part. Along 

the water courses are many valleys with broad bottom lands, while at the mouths 

of the largest rivers are extensive lowlands, formed by flood plains.

At the coming of the white man southeastern Alaska was inhabited by the 

Thlinkits and Haidas, native tribes which had developed a higher degree of 

civilization than any others of Alaska. These held not only the islands but also 

portions of the mainland, and were dependent for food on the abundant game 

and fish. In their large dugout canoes, fashioned of cedar, they made extensive 

journeys on the inland waterways. They were physically and mentally superior 

to the natives of the interior, and held them more or less in subjection, not 

permitting them to come to the coast. Later, when the white traders had established themselves, these coast natives became the middlemen for the trade with 

the interior, which was very lucrative until the English established themselves 

on the Yukon. Regarding this as an invasion of their territory^ they made a 

marauding expedition in 1852 and burned Fort Selkirk, one of the English posts 

established at the junction of the Pelly and Lewes rivers a few years before.

These natives were the last of the coastal tribes with which the Russians came 

in contact, and were never subjected by them. Baranof Island was selected for the 

first Russian settlement in the archipelago, and subsequently for the site of their 

capital, New Archangel, now known as Sitka. As southeastern Alaska was the 

most accessible region of the territory, it was the first to have its mineral resources 

developed. It now possesses a dozen centers of active mining operations, and has 

a larger permanent population than any other part of the territory. Next after 

mining, its most important industry is furnished by the salmon fisheries.

CKOSS SOUND TO PRINCE WILLIAM SOUND.

Between Cross Sound and the mouth of the Copper River the coast line trends 

northwest to southeast with comparatively even outline. Lituya Bay, about 40 

miles northwest of Cross Sound, a T-shaped indentation, is connected with the ocean

a Prof. Paper U. S. Geol. Survey No. 1,1902, pp. 35-37.
COASTAL FEATURES AND ISLANDS. 21

by a narrow channel. The most extensive embayment along this portion of the 

coast is Yakutat Bay, which is shaped like a funnel. From the upper end of 

Yakutat Bay a long arm, known as Disenchantment Bay, stretches to the southeast. 

The southern portion of this arm is separated from the ocean by a broad morainic 

flood plain that receives a number of large glaciers from the St. Elias Range 

(PL XXIII, £).

Near the mouth of the Copper River the coast line bends abruptly to the northwest, and the shallow embayment thus formed is known as Controller Bay. 

Between Controller Bay and the ocean is Kayak Island, which is probably the 

point in Alaska first reached by white men (p. 107). Kayak Island and the adjacent 

Wingham Island have comparatively low relief, as has also Middleton Island, 

which has an area of only a few square miles and lies about 50 miles to the 

southwest in the open ocean.

At Copper River delta is a broad lowland and shoal waters extend for some 

distance seaward, but westward the shores are again abrupt and the waters deep. 

Prince William Sound, whose entrance lies about 50 miles west of the mouth of the 

Copper River, has a very irregular outline. Its channels and fiords penetrate far 

into the Chugach Mountains, from which they receive many glaciers, and the 

surface .rises rapidly from sea level to 6,000 and 7,000 feet. The sound contains 

numerous islands, the largest of which, Montague and Hinchinbrook, separate it 

from the open sea. The coast line has the same character along the southern 

margin of the Kenai Peninsula.

COOK INLET.

Cook Inlet, the largest embayment of the Pacific coast line, stretches northeasterly about 150 miles and then makes an abrupt bend, continuing eastward about 

30 miles under the name of Turnagain Arm. The shores of the latter are abrupt 

and rocky, but along- Cook Inlet the coastal relief is more gentle. The northern 

end is bounded by the broad flats of the lower Sushitna River, and its eastern shore 

is formed by a plateau 300 to 400 feet high, which slopes westward from the base of 

the Kenai Mountains. \

A broad gravel plain 75 to 150 feet high extends northwest of the upper end 

of the inlet, and plain and plateau present to the water front steep escarpments, at 

the foot of which there is a beach of varying width. On either side of the entrance 

to the inlet the shores are abrupt and more or less irregular. A small island in 

this part contains the beautiful Augustine Volcano (see PL X, A).

SOUTHWESTERN ALASKA.

A group of islands is cut off from the mainland by Shelikof Strait. Kodiak, 

which is about 100 miles long and 40 miles wide, is the largest of these and also 

one of the largest islands of Alaska. It is characterized by comparatively low 

relief not more than 3,000 or 4,000 feet and many broad, open valleys with 

gentle slopes. These highlands have been described as a southern extension of the 

mountains of the Kenai Peninsula. On the southeastern shore of this island the
22 GBOGBAPHY AND GEOLOGY OF ALASKA.

Russians (p. 110) made their first permanent settlement in Alaska, in 1783. North 

of Kodiak lies Afognak Island and innumerable smaller ones.

Southwest of Kodiak the shore line has the same broken character as along 

Prince William Sound, and usually rises rapidly to the slopes of the Aleutian 

Range. In the extended axis of the Kodiak group lie three small clusters of 

islands known as the Semidi, the Shumagin, and the Sannak islands, all of strongrelief and irregular .shore lines.

ALEUTIAN ISLANDS.

This archipelago, the most extensive of Alaska, stretches from the extremity 

of the Alaska Peninsula 1,200 miles toward the Siberian coast. Its axis at first 

trends about 70° south of west, but turns near the one hundred and seventyninth meridian into a direction 70° north of west. The islands lie in a belt 20 to 

50 miles in width, and their shore line has the same irregularity that characterizes 

most of the Pacific coast. The relief is greatest near the eastern end of the 

archipelago and decreases to the west. Little is known of this chain with the 

exception of its eastern end, which has received more attention because it lies on 

the steamer route to the Bering Sea and Arctic Ocean.

Unimak, the easternmost of the chain, is separated from the mainland by a 

very narrow strait and from the rest of the group by Unimak Pass, which is 

the usual thoroughfare of vessels bound for the northern Bering Sea. It is about 

70 miles long and 25 miles wide, and contains at least two active volcanoes, the 

highest of which is Shishaldin, which has an altitude of 8,000 feet. The largest 

of this group, Unalaska, is of importance, because it contains a coaling station 

and the port for north-bound vessels. Its highest point is Makushin, a volcano 

about 4,000 feet in altitude. So little is known of the islands to the west that 

it is hardly worth while to mention them individually. The westernmost group, 

better known as the Near Islands, marks the western limit of Alaskan territory.

The Aleutian Islands are still occupied by an aboriginal population, though the 

ravages of the Russian fur traders at one time threatened to almost exterminate 

it. These natives make their way from one island to another in their skin 

boats, which are similar to those used by the Eskimos. They have depended 

for their living chiefly on the capture of the valuable sea otter, but this 

animal is now threatened with entire extinction.

NAVIGATION.

The coastal navigator of southern Alaska can in clear weather usually locate 

himself by some mountain peak or headland, and will find deep water close to 

shore. When fogs prevail, the many rocky islets and barriers studding the 

channels and inlets are, even when charted, a constant menace. The enormous 

tide of this part of the Pacific forms an additional source of peril, as when 

confined to narrow waterways it produces strong tidal rips dangerous to encounter 

in rocky channels. The abundance of good harbors along this coast, however, 

offers ready shelter from storms.
COASTAL FEATURES AND ISLANDS. 23

NORTHERN ALASKA. 

GENERAL FEATURES.

The coast features of the southeastern shore of Bering Sea are similar to those 

of southern Alaska, but north of Bristol Bay and the Alaska Peninsula shallow water 

is usually found near the land. The shore line is very regular, and the slope of the 

shallow sea floor is preserved by the land shelving gently from the sea. In many 

places the surface rises inland by a series of terraces. The characteristic topographic features are bold headlands connected by crescent-shaped beaches with 

even shore lines, which are sometimes almost straight and uninterrupted for many 

miles (see Pis. VI and XXX, A). An abrupt escarpment often marks the limit of 

wave action, and where there has been a series of recent elevations, a succession 

of benches gives an echelon type of topography to the coastal zone. Occasionally a 

terrace broadens out to many miles in width, forming a coastal plain. This is 

well illustrated by the map of the western end of the Seward Peninsula (PI. VI), 

and the photograph of part of the same general region (PI. XXX, A).

Another typical feature of the northern coast line is the barrier beaches which 

are built up by the surf in shallow water. These beaches extend parallel to the 

general trend of the coast and are usually separated from the mainland by shallow 

salt-water lagoons. In some instances such lagoons form almost continuous waterway's for many miles along the coast and are used as routes of communication by the 

natives when the open sea is too rough for their skin boats.

While these types of coastal topography are dominant they are by no means the 

only ones to be found. For example, the Seward Peninsula contains at least one 

tidal inlet, Imuruk Bay, which has the bold shore line characteristic of the indentations so common on the Pacitic coast.

BERING SKA COAST.

Bristol Bay, a deep indentation of triangular outline bounding the Alaska Peninsula on the north, is practically the meeting place of the northern and southern 

coastal types; in outline it resembles the southern, while in detail it conforms to the 

northern. It is split at its upper end into two minor bays, which are unnamed. 

Among the margins of these embayments low gravel beaches slope up to coastal 

plains. To the northwest a smaller indentation, which has received the name 

Kulukak Bay, is cut off from Kuskokwirn Bay on the north by a minor peninsula, 

whose highlands are part of the Ahklun Mountains (see p. 38, PI. VII).

From Kuskokwirn Bay northward the deltas of the two greatest rivers of Alaska 

the Yukon and Kuskokwim present to the sea a front of over 300 miles, in the 

form of a low coastal plain (pp. 39 et seq.). The coast line here bends to the northeast 

and between the Yukon Delta and the southern shore of Seward Peninsula is the 

great embayment of shoal water known as Norton Sound. Fifty miles northeast of 

the Yukon Delta lies a small group of islands, on the largest of which St. Michael 

is the port where transfers are made from the ocean steamers to the steamers which 

ply on the Yukon River. The upper end of the sound, because contracted by a 

minor peninsula on the south, is known as Norton Bay.
24 GEOGRAPHY AND GEOLOGY OF ALASKA.

The southern coast of Seward" Peninsula is broken by Golofnin Bay and Port 

Clarence with its several arms; the northern, by a succession of lagoons, of which 

the largest is known as Shishmaref Inlet. The following description is quoted from 

the report cited:

"Two kinds of shore-line topography can be differentiated one characterized 

by a low coastal plain, with many lagoons and sand spite; the other by bold cliffs 

that rise abruptly from the sea or from a narrow, rocky beach. Broadly speaking, 

the coast topography of the western half of the peninsula is mainly of the first 

description, while that of the eastern half is more bold and rocky.

"The lower part of Golofnin Bay is bounded on both sides by rocky cliffs, with 

narrow, shelving beaches. The precipitous character of the coast extends westward 

for about 30 miles, until near Topkok Head the escarpment recedes inland and a 

coastal plain intervenes between the uplands and the water line. This coastal plain 

broadens rapidly westward, until at Port Safety it attains a width of about 12 miles. 

Thence, sweeping around behind the highland that forms the blunt, rocky headland 

known as Cape Nome, it continues westward with gradually decreasing width to 

Rodney Creek, where the escarpment that marks the beginning of the highlands is 

not more than half a mile from the sea. Between Cape Nome and Topkok the 

continuity of the shore line is broken by large lagoons and other similar bodies of 

water. West of Cape Nome the shore line, as far as Cape Rodney, is almost straight 

and uninterrupted save for the tidal inlets at the mouths of the larger rivers. This 

coastal plain is nearly level, sipping gently toward the sea, here and there interrupted 

by an escarpment and carried to a higher level by a well-marked bench.

"From Cape Rodney the coastal plain is of varying width, including numerous 

salt-water lagoons and lakes. At Port Clarence it runs out into a long, narrow 

sand spit embracing the harbor. Inside of this sand spit the eastern shore of Port 

Clarence presents a bold wall of cliffs, with only here and there a crescent-shaped 

beach.

" As both Grantley Harbor and Imuruk Basin are subject to the ebb and flow of 

tides, their shore lines must be considered part of the coast line. Two narrow sand 

spits, between which a deep channel is kept open by the tide, separate Grantley 

Harbor from Port Clarence, and a narrow, winding canal with steep rock walls 

connects it with Imuruk Basin. From the southern shore of Imuruk Basin the 

Kigluaik Mountains rise abruptly, almost from the water's edge. At the upper 

end of the basin and encircling it on the north is a flat, swampy plain, pitted witli 

water bodies large and small, the partially filled portion of the greater depression 

which the basin once occupied.

"Along the open coast on the north side of Port Clarence is a low plain which 

includes a lagoon about 20 miles long. To the west, near Cape York, cliffs rise 

abruptly from the water, with only an occasional small beach. These cliffs are 

unbroken except by stream valleys and at York, where there is a small crescentshaped plain half a mile in width between the upland and the beach.

"From Cape Prince of Wales to Shishmaref Inlet the coast line is not marked 

by any escarpment, and a gently sloping plain extends for some distance inland. In

'*Brooks, Alfred II., Reconnaissance in Cape Nome and adjacent gold fields, U. S. Geol. Survey, 3901, pp. 49-51.
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 45 PL. IV

A. VIEW L-OWN GASTINEAU CHANNEL FROM MOUNT JUNEAU. 

Showing typical shore topography of southern Alaska.

B, HUNTER BAY, PRINCE OF WALES ISLAND, 

Illustrating deep-water conditions close to land.
U. S. GEOLOGICAL SURVFV PROFESSIONAL PAPER NO. 45 PL. V

GASTINEAU CHANNEL AND JUNEAU. 

Showing abrupt slope from tide water.
U.S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 45 PL. VI

WESTERN END OF 

SEWARD PENINSULA

showing the York Mountains and typical 

shore topography of noithernAlaska

Topography byT. G. Gerd 

and Alfred H. Brooks,1901

Contour interval 200 feet

Datum, is mean- sea- level. 

1904

I
COASTAL FEATURES AND ISLANDS. 25

this plain are narrow salt lagoons and lakes, one near Cape Prince of Wales being 

about 20 miles in length. An abrupt escarpment is said to bound the water from 

Shishmaref Inlet nearly to Cape Espenberg, but the cape itself is a low sand spit."

ARCTIC OCEAN COAST.

Cape Espenberg, the northernmost point of the Seward Peninsula, and Cape 

Krusenstern, to the northeast, mark the entrance to Kotzebue Sound, the largest 

indentation of the Arctic coast line of Alaska. This body of water has a fairly even 

shore line on the south, but on the east is broken up into numerous embayments, of 

which Hotham Inlet and Eschscholtz Bay are the largest. The following description 

is quoted from Mendenhall:"

"The long, slender peninsula separating Hotham Inlet from the main waters of 

Kotzebue Sound has but little relief; in the northern part, where it is broadest, 

heights of but 300 to 400 feet are reached. Long stretches of shore stand at about 

the level of extreme high tide, and the occasionally recurring shore bluffs of sand, 

clay, and frozen muds do not run generally more than 100 feet above mean-tide 

level. Choris Peninsula, the highest point of this long spit, has its summit 360 feet 

above the water. Along the southern shores of Kotzebue Sound low sea cliffs and 

flats alternate, the latter marking the outlets of streams. Rounded ridges and hills, 

sometimes reaching heights of 1,200 to 1,300 feet, but usually lower, extend inland 

and separate the wide, flat river valleys. The Kiwalik, Swan (Kugruk), Ipnechuck 

[Inmachuk], and Groodhope rivers are the principal streams entering the sound from 

the south. The Auckland River, larger than any of these, flows into Eschscholtz 

Bay from the southeast."

A low coast line, with long stretches of sandy beaches diversified by lagoons 

and tidal inlets, stretches northwest from Kotzebue Sound to Point Hope, a jutting 

sand spit, then turns due north for 100 miles to Cape Lisburne, and bending at right 

angles extends due east for 60 miles. While this shore line is low, hills, some of 

them mountains in height, are not far inland. These are the terminations of the 

great Kocky Mountain system, which stretches through the western United States 

(PI. II), Canada, and northern Alaska.

After this easterly trend the coast curves broadly to the northeast and continues 

in the same general direction to Point Barrow, the northernmost cape of the continent. To about Cape Beaufort the character of the coast is determined by an upland 

region, which is probably part of the plateau adjacent to the Rocky Mountains on 

the north and which extends almost to the sea. Near Cape Beaufort this upland 

falls off to a lower upland, which extends northward for several hundred miles and 

ends in an escarpment, marking the southern end of the coastal plain proper. 

Throughout this region a sandy beach and narrow coastal plain intervene between 

the upland and the sea.

The coastal plain of the north Arctic slope has already been described as lowland, which, sloping gently to tide water, is extended seaward by the shallow ocean 

bottom. It fronts the entire north Arctic coast, from near Cape Belcher to the

o Reconnaissance from Fort Hamlin to Kot/ebue Sound: Prof. Paper U. S. Geol. Survey No. 10, 1902, p. 27.
26 GEOGRAPHY AND GEOLOGY OF ALASKA.

international boundary. The actual shore line is characterized by long stretches of 

crescent-shaped, sandy beaches, often cut off from the mainland by large lagoons. 

Considered in detail, it is very regular, yet the contour as a whole follows many 

variations; broad embayments, some of which run far inland, alternate with sand spits 

or low forelands, giving the coast a cusped aspect. The mouths of the larger rivers 

are marked by indentations, and even where there are no considerable tributaries 

the shore line is frequently broken. Small, low islands, sometimes in short chains, 

in places lie close to land.

As this north shore line has not yet been surveyed in detail, no more than a 

general description of it is possible. Of the characteristic indentations mentioned 

Dease Inlet, a deep bay into which Chipp River empties, is 20 miles southeast of 

Point Barrow, and with Smith Bay on the east cuts out a minor peninsula of the 

coast. Still farther east lie Harrison, Gwydyr, and Camden bays and Yarmouth 

Inlet.

NAVIGATION.

This northern type of shore line presents both advantages and disadvantages 

to navigation. The rocky reefs and barriers, which are so dangerous to vessels on 

uncharted waters, are uncommon; but, on the other hand, the low coast line affords 

the navigator few points of recognition, and he is likelj- to encounter shoal water out 

of sight of land. The most serious drawback, however, is the almost utter lack of 

good harbors. At Nome the absence of shelter from southerly storms has within 

the past four years caused the loss of hundreds of thousands of dollars in vessels 

and cargoes. The rise and fall of tides in the Arctic Ocean and Bering Sea is 

compartively small, so that, as the even shore line offers few narrow straits, this 

coast is comparatively free from strong tidal currents.

ISLANDS.

The Alaskan islands of the Arctic Ocean are too insignificant to be worthy of 

note, but those of Bering Sea are numerous and often of considerable importance. 

Several of these, though belonging to Alaska as some of the Aleutian chain for 

instance are far distant from its shores.

Bering Strait, like the waters which it connects, is comparatively shallow, with 

a maximum depth of about 32 fathoms. The strong current" drawing through it 

to the north is probably the cause of its remaining open during the winter, when 

the seas which it connects are covered with ice, for such records as are available go 

to show that the strait is very seldom frozen over.

In the middle of Bering Strait, on either side of the boundary between Alaska 

and Siberia, rise the Diomede Islands, the smaller, Little Diomede or Krusenstern, 

belonging to Alaska, and the larger, Big Diomede or Romanzof, to Siberia. Both 

have steep shores rising to flat-topped summits, which occupy nearly their entire 

areas. The eastern or Alaska channel of the strait has a width of about 30 miles,

'i.Iarvis, D. II., Alaska coast pilot notes on the Pox Island passes, Unalaska Bay, Bering Sea, and Arctic Ocean as far 

as Point Barrow: Bull. U. S. Coast Survey, No. 40, p. 53.
GEOGRAPHIC FEATURES. 27

while the western or Siberian is somewhat narrower. Fairway Rock, a flat-topped 

pinnacle with an area of several acres, lies in the eastern channel."

About 50 miles due south of Cape Prince of Wales is King Island. This islet, 

which is little more than a double-peaked hill only a few square miles in extent, rises 

about 600 feet above sea level, and so steep are the slopes that the scanty Eskimo 

population has developed a form of hillside dwelling partly supported on poles. Its 

steep, rocky shores are broken only here and there by beaches, where landings can 

be made.

St. Lawrence Island, about 150 miles south of Bering Strait, is about 100 miles 

long by 10 to 30 miles wide. It is mountainous, the higher peaks reaching altitudes 

of probably 2,000 feet, and the shores rising by an abrupt escarpment from a narrow 

beach. It has a considerable Eskimo population, which communicates with the 

mainland by means of large skin boats, called "oomiaks. 1 '

St. Matthew and Hall islands, which lie I TO miles southwest of St. Lawrence, 

deserve only passing mention. They are small, of rather low relief, and have no 

particular importance. Almost due east of the last-mentioned islands is Nunivak 

Island, which is cut off from the mainland at the Yukon delta by Etolin Strait. This 

is a large island of low relief, chiefly notable because it is a serious menace to 

navigation, as it lies near the track of vessels bound for Nome.

From a commercial standpoint the most important islands in the Bering Sea are 

the Fribilof Islands, which lie well out in the Bering Sea southwest of Nunivak and 

nearly 500 miles south of Cape Prince of Wales. Besides some smaller rocky islets 

and reefs the group includes St. Paul and St. George, two islands of low relief and 

gently sloping shores. The great importance of the Pribilof Islands is due to the 

fact that they are the breeding ground of the fur seals. The estimated value of the 

fur-seal catch, from the purchase of Alaska to 1901, aggregated $35,000,000.*

In 18TO the islands became, by Congressional enactment, a Government reservation, on which the right to kill fur seals is sold to the highest bidder. The 

ravages of the Canadian pelagic sealing vessels in this neighborhood has led to the 

long seal-fishery controversy with England.

OROGRAPHIC FEATURES.

INTRODUCTION.

It has been shown that Alaska is geographically divisible into four provinces, 

which can be regarded as northerly extensions of similar provinces in the western 

United States and Canada. Naming them from south to north, they are the Pacific 

Mountain system, the Central Plateau region, the Rocky Mountain system, and the 

Arctic Slope region (PI. VII). Of these the first, adjacent to the southern coast, 

has the greatest relief, as it embraces several of the highest mountains on the

« Projects for the connection of Alaska and Siberia by railway are current in periodical literature. Such a railway would 

require a tunnel in four sections. The easternmost, connecting Cape Prince of Wales with Fairway Rock, would be 20 

miles in length. The next, to Krusenstern Island, would have a length of 10 miles. The third section, to Romanzof 

Island, would be comparatively short, while the fourth, joining Romanzof Island and the Siberian coast, would be at 

least 25 miles long. The ferry connection between the two continents would be impracticable in winter because the ice 

floes that are swept through the strait during half the year make it entirely unnavigable.

& Austin, O. P., Commercial Alaska in 1901: Summary of Finance and Commerce, Treas. Dept. Bur. of Stat., May, 

1902, p. 3943.
28 GEOGRAPHY AND GEOLOGY OF ALASKA.

continent, while the Arctic Slope region, the northernmost of the provinces, is the 

one of lowest relief. Broadly speaking, all of the orographic features decrease in 

altitude toward the north and west.

PACIFIC MOUNTAIN SYSTEM. 

GENERAL RELATIONS.

The Pacific Mountain system embraces a broad zone of ranges, and stretches 

parallel to the southern coast line of Alaska, forming, like it, a reentrant angle, 

or, more properly, a curve concave toward the south. The system is broadest near 

the apex of the angle, narrowing toward the southeastern boundary of the territory 

on one hand and toward its southwest limit in the Alaska Peninsula on the other.

Besides numerous inferior tranverse lines of height, this system embraces four 

important ranges, whose extended axes are approximately parallel to each other and 

to the general trend of the coast line (see PI. VII). Of these the Coast Range, the 

St. Elias Range, and the Aleutian Range lie adjacent to the coast, while the Alaska 

Range is inland and forms the northern border of the system.

In British Columbia the system embraces only the Coast Range, unless the 

highlands of Vancouver Island" be regarded as a distinct range. This simplicity of 

structure is continued for about 900 miles northward as far as Lynn Canal, but 

west and northwest of this point the system becomes more complex and embraces 

two or three distinct ranges, separated in some instances by broad valley basins, 

in addition to other subordinate mountain masses.

COAST RANGE.

The Coast Range extends from near the boundary of Washington northward 

through British Columbia into southeastern Alaska, where it lies partly in Alaska 

and partly in Canadian territory. Following the coast line for nearly 900 miles, it 

passes inland behind the St. Elias Range near the head of Lynn Canal. Thence it 

can be traced northward, decreasing in altitude and gradually losing definition until 

it finally merges with the interior plateau near Lake Kluane in longitude 138° 30'.

This range has no well-defined crest line, but is rather a complex of irregular 

mountain masses, occupying a coastal strip between the Pacific Ocean and the 

Central Plateau region. Both Haves* and Dawson c have called attention to the 

uniformity of the summit levels between altitudes of 5,000 and 6,000 feet in Alaska, 

and 8,000 and 9,000 feet in British Columbia, which, viewed from a similar altitude, gives the range the appearance of a dissected plateau (PI. XXVIII, A). This 

feature will receive further consideration in the discussion of the topographic 

development (p. 287).

The limits of the Coast Range are not always sharply defined, as in many 

places it merges with the Central Plateau, and on its seaward side is sometimes

nDawson differentiated the Coast Range from the Vancouver Range, a subdivision which the writer does not deem 

justifiable. Trans. Royal Soc. Canada, 1890, vol. 8, see. 4, p. 4.

bHayes, C. W., An expedition through the Yukon district: Nat. Geog. Mag., vol. 4, 1892, p. 128.

cDawson, G. M., Report on the area of the Kamaloops map sheet, British Columbia: Ann. Rept. Geol. Survey 

Canada, new series, vol. 7, 1894, p. 10 B.
PACIFIC MOUNTAIN SYSTEM. '29

not clearly differentiated from the mountains of the Alexander Archipelago. It 

has a width of about 100 miles near Fraser River, which decreases to about 50 

miles near Lynn Canal.

Considerable areas on the coast side of the range are drained by the Taku 

and Stikine, two large rivers flowing seaward transverse to its axis; while the 

Unuk, a smaller river following a similar course, probably receives some of 

the inland drainage. On the seaward face of the range most of the drainage is 

carried to salt water by many small streams that flow through sharply cut 

valleys, and have their sources in glacial cirques, which are frequently still occupied by ice. The larger streams of this class, such as the Skagway and Dyea 

rivers, occupy typical U-shaped glaciated valleys. The range is often indented 

and interrupted by the many tidal waterways already described (see pp. 18-20).

The sea slope of the Coast Range has a heavy precipitation, which falls chiefly 

as snow in the higher valleys and on the mountains, but near sea level in the form 

of rain. In Alaska the lower reaches of the Pacific slope are heavily forested 

with spruce, hemlock, cedar, and alder (see PI. XII). The upper limit of thick 

timber, which is about 4,000 feet near Dixon Entrance, descends northward until 

near Lynn Canal it is about 3,000 feet. The inland slopes of the range, except 

where broken by broad valleys, have a low precipitation.

ST. KLIAS RANGE.

The name St. Elias Range" has usually been applied to the rugged mountain 

mass along the coast of Alaska between Cross Sound and Mount St. Elias. Here 

the name is given a broader significance and includes the Chugach, Kenai, and 

Skolai mountains, which are orographically a western extension of the St. Elias 

Range. The mountains of the Alexander Archipelago are properly a southeastern 

extension, but as they are separated from the mainland and divided into different 

groups by broad tidal waterways they can hardly be included under the same 

name.

Thus denned, the St. Elias Range extends northwesterly from Cross Sound, 

bends westerly near the mouth of the Copper River, and near the head of Prince 

William Sound, in longitude 147C , turns sharply southwest and merges into the 

highlands of the Kenai Peninsula. Near the one hundred and fortj'-second 

meridian the chain is parted by the valley of the Chitina River into two divergent ranges. The southernmost, here called the Chugach Mountains, forms the 

main range across the head of Prince William Sound. The northernmost, under 

the name of the Nutzotin Mountains, stretches westward and forms a connecting 

link between the St. Elias and Alaska ranges.

The St. Elias Eange is a rugged mountain mass throughout its extent, varying 

in width from 50 miles near Cross Sound to nearly 100 miles at Mount St. Elias, 

and then narrowing down to less than 20 miles to the southwest in the Kenai 

Peninsula.

Near Cross Sound some peaks of the Fairweather group rise abruptly 

from tide water to altitud.es of over 15,000 feet. Westward the range increases

nThere seems to be no warrant for the term "St. Elias Alps," used by some writers. 

17211 No. 45 06 3
30 aEoaRAPHY AND GHEOLOGY OF ALASKA.

in height and complexity, culminating in Mount St. Elias (PI. VIII, A) and 

Mount Logan, 18,024 and 19,500 feet in height. Here the mountain front is 

20 to HO miles from the coast, and the intervening space is occupied b}' a 

series of foothill ridges, or a shelving coastal plain, in man}^ places covered by 

huge glaciers. This part of the range, as yet practically unexplored, consists of 

a complex of rugged peaks, with intervening valleys and depressions deeply 

buried in glacial ice and snow. Russell, who viewed it from the upper slopes 

of Mount St. Elias, describes it as "a vast snow-covered region, limitless in 

expanse, through which hundreds and probably thousands of barren, angular 

peaks project. There was not a stream, not a lake, not a vestige of vegetation 

in sight. A more desolate or a more utterly lifeless land one never beheld. 

Vast, smooth snow surfaces, without crevasses or breaks, stretched away to 

seemingly limitless distances, diversified only by jagged and angular mountain 

peaks.""

From Cross Sound to the Copper River the St. Elias Range forms a rugged 

coastal barrier, broken only by the broad valley of the Alsek River. As far as 

known, there are no passes through this part of the range, except some high 

divides occupied by glaciers.

West of St. Elias the southern fork, called the Chugach Mountains, stretches 

parallel to the coast, skirting the northern shore of Prince William Sound, then 

bending to the south merges into the lesser heights of the Kenai Mountains 

(PI. VII). This range, like the one to the east, is a complex mountain mass 

about 50 miles in width, whose peaks reach altitudes of 8,000 to 10,000 feet. It 

is broken near the one hundred and forty-seventh meridian by the valley of the 

Copper River, and farther west by several gaps, the lowest of which, called 

Thomson Pass, is the one used by the military trail which leads into the Copper 

River Valley from the coast. To the east the Chugach Mountains are practically 

unbroken. There is said to be a pass about 4,000 feet in height near the head 

of the south fork of the Chitina, but it has not been explored. The summits of 

these mountains, like those of the Coast Range, have a generally uniform 

altitude* (PI. XXVIH, S).

The Talkeet c Mountains form a minor range lying to the northwest of the 

Chugach Mountains, from which they are separated by the valley of the Matanuska 

River (PI. VII). On the north they are cut off from the Alaska Range by eastern 

tributaries of the Sushitna. To the east they fall off rapidly to the Copper River 

Plateau and to the west to the Sushitna River lowland. They are an isolated 

highland mass, which belongs to neither the Chugach nor the Alaska mountains 

and whose highest peaks, according to Mendenhall, probabh^ reach altitudes of 

5,000 to 6,000 feet.

A description of the Copper River Plateau properly belongs elsewhere, but this 

name is applied to the broad, flat basin which is drained by the Sushitna and Copper

a Mount St. Elias and its glaciers: Am. Jour. Sci., 3d scries, vol. 43,1892, p. 171.

l> Geology and Mineral Resources of the Copper River District: U. S. Geol. Survey, 1901, p. 65.

"Eldridge, G. H., A reconnaissance in the Sushitna basin and adjacent territory: Twentieth Ann. Rept. U. S. Geol. 

Survey, pt. 7,1900, p. 8.

Meiideiihall, W. C., A reconnaissance from Resurrection Bay to the Tanana River; Twentieth Ann. Rept. XT. S. Geol. 

Survey, pt. 7,1900, p. 297.
U.S.GEOLOGICAL SURVEY PRO! ESSIONAL PAPER NC\ 45 PL. VII

174° 170° W6° 162"1 136" 154° 150" 146* 142° 138° 116°

/ GEOGRAPHIC PROVINCES

AND

MOUNTAIN AXES

OF

ALASKA

BY 

ALFRED H.BHOOKS

17O° 154" West of Greenwich 150° 146*

JULIUS BIENtcOLITH NV
U. 8. GEOLOGICAL SURVEY PROFESSIONAL PAPER no. 45 PL. VIM

A. MOUNT ST. ELIAS FROM THE SOUTH.

MOUNT McKINLEY FROM THE NORTHWEST.
U. 6. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 45 PL. IX

A. MOUNT WRANGELL AN ACTIVE VOLCANO. 

View taken from the Government trail above Tonsina Bridge, 45 miles from the summit of the mountain.

B. MOUNT DRUM, COPPER RIVER REGION. 

A dissected crater.
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 45 PL. X

A. MOUNT ST. AUGUSTINE, COOK INLET. 

A typical ash cone.

INLAND FRONT OF ST. ELIAS RANGE, WHITE RIVER BASIN. 

Showing abrupt transition to the plateau.
PACIFIC MOUNTAIN SYSTEM. 31

rivers and is hemmed in by the Chugach Mountains on the south, the Talkeet Mountains and Alaska Range on the west and north, and the Wrangell Mountains on 

the east (PI. XIV, S).

Toward their western limit the Chugach Mountains bend to the south and 

merge with the Kenai Mountains (PI. VII), occupying the eastern half of the Kenai 

Peninsula. These are described by Mendenhall 0 as follows:

"The Kenai Mountains, as that part of the St. Elias system which forms the 

axis of the Kenai Peninsula is called, form a belt 60 miles wide in the northern part 

of the peninsula and somewhat narrower toward the south. But little is known in 

detail of the interior of these hills, but that little indicates that they reach altitudes 

of 6,000 or 8,000 feet; that they have been dissected by a drainage system which 

became fairly mature before it was disturbed, and that, therefore, they are intersected by rather broad, high vallej's. All their higher parts are snow clad, and 

numerous glaciers flow down from them to the inlets of the Pacific and become the 

sources of the streams which drain the peninsula."

The low gap, filled with glacial ice, which separates the Chugach and Kenai 

mountains has long been used by natives as a route of communication between 

Prince William Sound and Turnagain Arm. On the east side of the peninsula the 

coast line is indented by many ernbayments, and the mountains rise precipitously 

from the water; on the west they fall off more gradually to the Kenai Plateau, which 

stands about 200 feet above tide water. The highlands of Kodiak Island to the 

south can be regarded as a southern extension of the Kenai Mountains.

Near the one hundred and forty-first meridian the St. Elias Range is split by 

the valley of the Chitina River. The northern branch, sometimes called the Skolai 

Mountains, extends westward until cut off by the head of the Copper River. On 

the north it is separated from the Nutzotin Mountains by valleys of streams which 

are tributary to the upper Tanana, and on the south it merges into the Wrangell 

group. The Skolai Mountains are rugged, with altitudes of 7,000 to 10,000 feet. 

Schrader and Spencer ^ have called attention to their even crest line.

All the ranges thus far described as composing the Pacific Mountain system 

belong to that class of the earth's features which are the result of differential erosion 

in regions of deformation and uplift. The Wrangell Mountains, however, which 

in point of geographic position must be classed with the Pacific Mountain system, 

owe their origin to the accumulation of volcanic material in times so recent that 

the forces of erosion have not yet removed it. Their highlands have the irregular 

form characteristic of volcanic mountains which are built up of lavas rather than 

of ash deposits (see PI. IX, A and B).

Mendenhall e describes them as follows:

'' The Wrangell group occupies a rudely elliptical area, with the extensive lowlands 

of the Copper and the Chittyna [Chitina] valleys on the south and west, but connected 

toward the east with the somewhat greater heights of the St. Elias Alps. A wellmarked depression on the north, which extends from the upper Copper across the 

Nabesna and the Chisana to the White, separates them from the neighboring Nutzotin

a Mendenhall, W. C., A reconnaissance frorfl Resurrection Bay to the Tanana River, Alaska, in 1898: Twentieth 

Ann. Rept. U. S. Geol. Survey, pt. 7,1900, p. 296.

& Geology and Mineral Kesources of a portion of the Copper River District, Alaska: U. S. Geol. Survey, 1901, p, 66. 

oThe Wrangell Mountains, Alaska: Nat. Geog. Mag., vol. 14,1908, pp. 399-400.
32 GEOGRAPHY AND GEOLOGY OF ALASKA.

and Mentasta ranges. Measured along the greater diameter of the ellipse from 

Skolai Pass northwestward to the outer base of Mount Drum, the extent of the group 

is about 100 miles, while the other diameter at right angles to this is approximately 

70 miles in length. Within this area of 5,500 square miles are at least ten snow-clad 

peaks 12,000 feet or more in height. Several of these are unnamed, and two of them. 

Mounts Sauford and Blackburn, are higher than Mont Blanc or any of the peaks 

within the borders of the United States.

u^ * * * j- gf. Q^ ^ne principai peaks and their elevations * * * is 

appended here:

Feet. 

Mount Sanl'ord .......................................................................... 16, 200

Mount Blackburn ....._.................................................................. 16,140

Mount WrangeH ......................................................................... 14, 000

Mount Regal ............................................................................ IS, 400

Mount Zanetti........................................................................... 12, 980

Mount JarviH ............................................................................ 12, 300

Mount Drum ............................................................................ 12, 000

Capital Mountain ........................................................................ 9, 697

Mount Gordon .......................................................................... 9,100

Snider Peak ............................................................................. 8,345

. "In addition to these summits, to which names have been applied, there are two 

or three unnamed points on the ridge between Wrangell and Blackburn which are 

10,000 feet or more in height, while between Blackburn and Regal one peak is 13,400, 

another 12,925, and a third 12,185 feet high.

"The Wrangell Mountains lie between the meridians of 142° and 145° west 

longitude and the parallels of 61° 20' and 62° 30' north latitude. The one hundred 

and forty-fourth meridian and the sixty-second parallel intersect just east of the 

crater of the central peak Mount Wrangell."

Summary. The St. Elias Range is a rugged mountain mass parallel with and 

close to the Pacific coast from Cross Sound as far as the entrance to Cook Inlet, 

with one spur, the Skolai Mountains, stretching to the northwest. On the seaward side the range presents an abrupt escarpment, often rising directly from 

the water, while its northern slopes almost everywhere fall off abruptly to the 

Central Plateau.

Near Cross Sound the timber line is at about 2,500 feet, but the mountains 

are usually too steep to permit any but the scantiest growth of vegetation. 

Where a piedmont plain intervenes between the mountains and the water, it is 

clothed with dense forests of spruce with some hemlock and occasional cedar. 

Bordering Prince William Sound the forests are almost entirely of spruce and 

are limited to the lower 300 feet of the mountain slopes.

ALEUTIAN RANGE.

The Aleutian Range is the third of the coastal barriers of the Pacific Mountain 

system. It embraces the highlands which skirt the Pacific side of the Alaska 

Peninsula from Unimak Pass to Cape Douglas, at the entrance of Cook Inlet. 

This range trends northeast as far as Cape Douglas, where it ends abruptly, but 

an offset to the west, represented by a broad lowland, carries what is probably
PACIFIC MOUNTAIN SYSTEM. 33

the same mountain axis to the west side of Cook Inlet, where it is continued 

northeast by the Chigmit Mountains (PI. VII). The latter have been traced 

northward to about latitude 61°, where they fall oft' to a lowland. The mountainous Aleutian Islands, stretching nearly 900 miles westward from the mainland, 

are a southwest continuation of the Aleutian Range. Their shore lines are abrupt 

and rocky and their relief very strong.

The Aleutian Range of the mainland is at its greatest width almost 80 miles, 

near latitude 58°, where the topography is complex and irregular. Northward 

it rapidly narrows until at Cook Inlet it becomes a single ridge. Like the 

ranges previously described, it was first outlined by a zone of deformation and 

uplift, but its present relief is due, for the most part, to volcanic ejecta, and is 

made up of a series of volcanic peaks distributed at irregular intervals along a 

northeast-southwest axis. The highlands are broken by many broad, flat divides. 

Redoubt Volcano, the most northerly of these, is something over 11,000 feet in 

height. To the southwest the volcanic peaks decrease in altitude, the highest in 

the Aleutian Islands having an elevation of about 6,000 feet. Many of these 

show the beautiful, symmetrical form of typical ash cones. Among the finest is 

Mount Augustine, which forms a small island near the entrance to Cook Inlet 

(see PI. X, A).

Little is known of the western slope of the Aleutian Range. In about 59° 30' 

latitude the range falls off very abruptly to Lake Iliamna, but to the north, 

where it has been little explored, it does not appear to be sharply differentiated 

from the southern part of the Alaska Range.

Most of the Aleutian Range lies in the great timbeiiess belt which extends 

from the latitude of Kodiak Island on the Pacific, along the shores of Bering 

Sea, and northward and eastward along the Arctic Ocean to the vast barren 

ground area of northern Canada. Toward the northern end of the range, 

however, the lower slopes are timbered with spruce and birch, and nearly everywhere in the timberless region the lower valleys contain a thick growth of 

willow (PI. XII).

ALASKA RANGE.

The Alaska Range, the northernmost of the Pacific system, is a rugged mountain 

mass, which extends northeast from the vicinity of Lake Clark and, sweeping around 

the Sushitna and Copper River basins, forms the watershed between the Pacific 

drainage on the south and east and the Kuskokwim and Yukon waters on the north 

and west.

Its crest line, which is well defined and remarkably regular, lies close to its 

western margin. On the east and south a series of foothills intervenes between the 

mountains and the lowlands of the Sushitna Valley and the Copper River Plateau, 

while on the west the mountains descend abruptly to a gravel plateau, which slopes 

westward and merges with the Kuskokwim lowland (PI. XXXII, A). At the north 

front there is an equally abrupt transition from the rugged mountains to the lowland of the Tanana Valley. A very striking feature of the topography is the line 

marking the northwestern base of the range, which is remarkably even for 200 miles 

(see PI. XI). Of the southern projection of the range little is known; it probably
34 GEOGRAPHY AND GEOLOGY OF ALASKA.

extends southward and includes the mountainous region in the vicinity of Lake 

Clark. The axis of the range is crescent shaped (see PI. XI). It extends northeasterly to the one hundred and fifty-first meridian, thence easterly as far as the 

Tanaua; thence to the southeast to the Nutxotin and Skolai mountains, which link it 

to the St. Elias Range.

The mountainous bolt which constitutes this range averages 50 to 60 miles in 

width. As the crest line lies near the western margin, the easterly drainage courses 

lie in deep-cut valleys before emerging on the valley lowland of the Sushitna River. 

Because of this and of the greater precipitation on the coastal side of the divide, 

the streams flowing into the Pacific arc much larger than those to the west and north 

which thread the mountains in short valleys and then debouch upon the gravelfloored plateau.

No altitudes have been determined near the southern end of the range, but in 

the vicinity of Lake Clark the mountains probably do not rise above 5,000 a or 6,000 

feet. Toward the north the relief increases until near the sixty-second parallel the 

mountains have a height of 10,000 feet. In this region Mount* Spurr, south of the 

Yentna basin, has an altitude of 10,500 feet, while Mount Russell c and Mount Dall,* 

north of the Yentna batjin, reach elevations of 11,300 and 9,000 feet, respectively.

Spurr gave the name ; 'Tordrillo Mountains" to that part of the Alaska 

Range south of the passes connecting the Skwentua and upper Kuskokwim 

drainage basins. As these mountains are actually coextensive with the rest of 

the range they seem hardly to deserve a separate designation. Their peaks 

reach 6,000 to 7,000 feet in altitude. The broad valley of the upper Kuskokwim 

separates this part of the range from an area of lesser altitude, termed by Spurr 

the "Terra Cotta Mountains," which is also an integral though subordinate part 

of the Alaska Range.

During an exploration made in the summer of 1902 the writer saw from the 

distance another mountain group which belongs to this range, but is as yet 

unexplored. These mountains lie to the southwest of the upper Kuskokwim and 

apparently form the watershed between the Kuskokwim and Haliknuk basins. 

Their peaks reach above the line of perpetual snow, and they are the source of 

some small glaciers. These mountains appear to be a southwestward extension of 

Spurr's Terra Cotta Mountains, but they far exceed these in altitude.

The culminating peaks of the Alaska Range are Mount McKinley, 20,300 feet 

(PI. V1I1, B), the highest on the continent, and 14 miles to the south, Mount 

Foraker, 17,000 feet. Both lie in about latitude 63°. These two are dome shaped, 

and tower far above the adjacent mountains, which are 10,000 to 11,000 feet high. 

These peaks are visible from Cook Inlet and have been known to white men for 

nearly one hundred years, but were not indicated on maps until recently. Mount 

McKinley was known to the Russians as "Bulshaia" and to the natives of Cook 

Inlet as "Traleika," both names signifying high or big mountain. In 1895 it

a The writer is indebted for this information to Mr. Wilfred H. Osgood, of the Biological Survey, Department of Agriculture, who visited Lake Clark in 1902. 

b Named after J. E. Spurr by the writer. 

< Named after I. O. Russell by the writer. 

rt Named after William H. Ball bv the writer.
PACIFIC MOUNTAIN SYSTEM. 35

was named Mount McKinley by W. A. Dickey, who ascended the Sushitna River 

for a short distance and called attention to its tremendous height. In 1898 George 

H. Eldridge (p. 127) and Robert Muldrow, of the United States Geological Survey, 

determined its position and altitude, and in the following year Lieut. Joseph S. 

Herron (p. 13 L) named the second high peak "Mount Foraker." In 1902 a more 

extended exploration of the range was made by Alfred H. Brooks and D. L. 

iteaburn, who were the first white men to reach the base of Mount McKinley. 

Toward the northeast the range decreases in height to 7,000 and 8,000 feet near 

the Cantwell River, but still farther eastward, near the Tanana, there is a group" 

of mountains with altitudes of 9,000 to 14,000 feet.

In about latitude (>2° are several passes through the range at an altitude of 

3,000 or 4,000 feet/' These all lie in a belt 10 miles in length, and lead 

from the drainage basin of the Yentna on the east to the East Fork of the 

Kuskokwim on the west. Though traversed only a few times by white men, 

they have long been in use by the natives.

To the northeast the Alaska Range presents an almost unbroken crest line 

for nearly 200 miles. As far as known there are no gaps below the snow line 

until Caribou Pass, at the head of the Cantwell, is reached. This is a broad 

depression, compared with the southern passes, and stands at an elevation of only 

about 2,400 feet above sea level, dividing the Chulitna waters tributary to the 

Sushitna, on the south, from the Cantwell waters tributary to the Tanana, on the 

north. It is the lowest as well as the most practicable pass through the Alaska 

Range, and, like the southern passes, has long been used by the natives. One 

hundred miles to the east the Delta River breaks through the mountains and 

forms the only wafer gap in the range. The valley of Delta River, according 

to Mendenhall,'' is rather narrow, with precipitous walls. Between it and the 

Cantwell the range has not been explored, but it is hardly probable that there 

are any low passes.

The eastern end of the Alaska Range is split by streams tributary to the 

Tanana and White rivers into two masses; the northern, called the Nutzotin, and 

the southern, the Skolai Mountains (PI. VII). The latter would form a highland 

link between the Alaska and St. Elias ranges but for the intervention of the 

upper Copper River Valley.

In a previous report the writer has described the Nutzotin Mountains,'' from 

which the Nabesna and Chisaua rivers emerge to debouch on the broad gravel 

plain of the upper Tanana Valley. From the Nabesna these mountains extend 

southeasterly- as far as the White River, but in the last 20 miles decrease very 

much in elevation until they are merely low hills. If the axis of this range were 

extended southeast of the White, it would coincide with that of the mountains 

north of Lake Kluane, which attain considerable altitude. These, so far as observed, 

seem to constitute a more or less well-detined range as far as the Kaskawulsh

a Mount Hayes, 14,000 feet; Mount Kimball, 9,000 feet.

fr These passes Ptarmigan, Rainy, and Simpson have been explored and in part surveyed, and further exploration 

may discover others.

"Mendenhall, W. C., A reconnaissance from Resurrection Bay to the Tanana River: Twentieth Ann. Rept. U.S. 

«eol. Survey, pt. 7,1900, p. BOO.

<*Reconnaissance from Pyramid Harbor to Eagle City, Alaska: Twenty-first Ann. Rept. U. S. Geol. Survey, pt. 2,1900. 

p. 846.
U.S.GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 45 PL. XI.

Harper Bend

RECONNAISSANCE 1MAP OF

MT. MC KINLE Y REGION,

ALASKA

Coskakat

Alfred HBrooks, Geologist in charge.

Topography l>y D.Li.Reaburn.

Surveyed in 1902.

Additional information compiled from 

surveys "by U.S.Geo. Survey andll S.Army.

Contour interval 200 feet.

Datum is meansea level.

Probable drainage not surveyed. 

Dates indicate camps,

1904

- -. s ->'y <" 

UnsuzT Mt.

Mt Russel aiiaso

arewel I
36 GEOGRAPHY AND GEOLOGY OF ALASKA.

River, beyond which they probably merge with the Yukon Plateau, though the 

mountains lying immediately north of the Chilkat River may belong to the same 

uplift. This chain has an extreme width of about 20 miles, and its highest peaks 

reach elevations of 10,000 or 11,000 feet.

In the Nutzotin Mountains are numerous gaps ottering routes of trave 

between the Copper River and the Tanana, of which the Mentasta and Suslota 

passes are the best known. To the east the mountains are broken by the vallevs 

of the Nabesna and Chisana rivers, which rise south of the Nutzotin Mountains 

in the Skolai Mountains and unite later to form the Tanana.

The southern and eastern slopes of the Alaska Range near Cook Inlet, up to 

about 1,200 feet, constitute a beautiful park-like region, sprinkled with groves of 

spruce, birch, and cottonwood, and abundant open meadows of fine grass. Between 

1,200 and about 3,000 feet is a belt of alder and willow thickets. In the upper 

Sushitna and tipper Copper River valleys the limit of thick timber rises somewhat 

and spruce pred /minates (PI. XII).

Timber covers the western and northern slope of the range up to between 

3,500 and 4,000 feet, and is much smaller than on the coast side of the divide, 

consisting chiefly of spruce, with some white birch and cottonwood. Near the 

upper limit of spruce timber there is an abundance of good grass. Stunted willow 

is found in the high valleys and gulches up to an altitude of 4,000 to 5,000 feet.

CENTRAL PLATEAU REGION. 

GENERAL FEATURES.

North and west of the rugged, snow-covered ranges of the Pacific Mountain 

system the aspect of the country changes abruptly (Pis. X, B, and XXX, 13}. 

A rolling upland about 200 miles wide, deeply dissected by well-developed drainage 

systems, with stream valleys and broad lowlands, and diversified by scattered 

mountain masses and isolated peaks that rise above the general level, stretches 

from the Pacific Mountain system on the south to the Rocky Mountain system on 

the north and from the lowlands which skirt Bering Sea to beyond the international 

boundary (PI. VII). Broadly speaking, its limits correspond with those of the 

Yukon and Kuskokwim basins combined. While this province as a whole is an 

upland region, it includes a number of large lowland areas, such as the coastal 

plain, which will be described later (pp. 39 et. seq.).

One traversing the valleys and lowlands only of this central province might 

describe it as an agglomerate of hills, ridges, and mountains irregularly distributed 

and without system, but from a higher altitude the tops of the hills and ridges 

appear to mark a gently undulating plain. From about the level of this plain 

the drainage channels are almost entirely hidden and the upland surface sweeps 

off to the horizon, broken only here and there by peaks or mountain masses 

which rise above the general level (see Pis. X, _5, and XXX, J3). Such a view 

conveys almost the same impression of monotony as one across the Great Plains 

east of the Rocky Mountains, and shows the strong contrast between the plateau 

province and the rugged mountains on either side. Flat-topped interstream areas
CENTRAL PLATEAU REGION. 37

mark the remnant of a dissected plateau, called by Hayes" the "Yukon Plateau," 

whence this province derives its name of "Central Plateau region'' (PI. VII).

This plateau province of Alaska is coextensive with that of British Columbia 

and Yukon Territory, called by Dawson the " British Columbia Plateau." As 

has already been shown, the same general physiographic feature can be traced 

northward from the western United States through Canada into Alaska.

ALTITUDE OF PLATEAU.

Near the northern boundary of British Columbia (latitude 60°) the plateau 

has an altitude of about 5,000 feet at its western margin; it slopes downward 

toward the center of the province and probably rises again toward the Rocky 

Mountain front. Jt also declines northwestward to an altitude of about 4,000 

feet near the intersection of the sixty-third parallel with the Yukon.

The plateau continues its northwesterly direction as far as the great bend 

of the Yukon, then encircling the broad lowland known as the Yukon Flats, it 

falls off still more to the southwest until it has an altitude of less than 2,000 

feet near the Lower Ramparts, latitude 66°. In the Koyukuk basin the plateau 

level is apparently represented by hills whose summits stand at altitudes of 

about 3,000 feet.*

The region northeast of the Yukon has been little explored, but the plateau 

province probably extends to the front of the Rocky Mountain system, about 50 

miles northeast of Dawson, and embraces the valleys of most of the tributaries of 

the Yukon.

The lower Yukon and Kuskokwini offer less definite evidence of the plateau, 

for the topography is characterized by broad lowlands interrupted by irregular 

hills and ridges, which seldom rise above 2,000 feet, and decrease in height 

toward the coast. These may be remnants of the plateau.

SEWARD PENINSULA UPLAND.

The Seward Peninsula, as a whole, falls within the plateau province, though 

here the plateau feature itself is not strongly emphasized. The characteristic topographio"1 types are rounded hills and ridges 800 to 2,000 feet in height, forming 

an irregular upland, which usually rises away from the coast (PI. XIII). This 

upland is broken by many broad valleys with gentle slopes, which in some cases 

become basin lowlands of considerable extent; and is diversified l)j isolated peaks 

and several larger mountain masses which rise above the general level. Old 

degradatiomil surfaces are marked by high benches and terraces up to a height 

of about 1,500 feet. Some of these have been ascribed by the writer to marine 

erosion, and they may belong to the same period as the Yukon Plateau. This 

theory, however, seems hardly tenable in view of the improbability that such a 

comparatively insignificant feature would be preserved during the long period 

which has elapsed since the uplift of the Yukon Plateau.

n.Iour. School Geog., vol. 1, 189V, p. 239.

''St'hradcr, E. C., Reconnaissance along the O'handlar and Koyukuk rivers, Alaska: Twenty-first Ann. Kept. U. S. 

Geol. Survey, pt. 1, 1900, p. 464.

 'Reconnaissance in the Cape Nome and Norton Buy Regions, Alaska, in 3900, U. S. Geol. Survey, 1901, pp. 16-20.
38 GEOGRAPHY AND GEOLOGY OP ALASKA.

BOUNDARY OF PLATEAU AND MOUNTAIN KANGES.

In northern British Columbia the line between the plateau and Coast Range 

is not sharply drawn, because of a gradual merging of the topography of the 

two provinces. In Alaska, on the other hand, the change from the plateau 

province to the bounding mountain ranges is often very abrupt. This feature is 

especially striking along the northern front of the St. Elias Range, where the 

smooth, grassy, flat-topped remnants of the plateau end abruptly against the steep 

slopes of the rugged, snow-covered mountains. In the upper White River basin 

an escarpment usually marks the boundary (see PI. X, B). Similar relations 

were observed in the upper Tanana Valley, where the Alaska Range falls off 

abruptly to the plateau, and also along the northwestern front of the Alaska 

Range, in the headwater region of the Cantwell, where the remnants of the plateau 

stand at about 3,000 feet. Farther to the southwest the front of the Alaska 

Range is deeply buried in overwash gravels, and the piedmont plateau thus 

formed obscures the definition of the plateau proper, which may be represented 

by some flat-topped spurs, seen as prominent shoulders along the front of the 

range, at an altitude of about 4,000 feet.

The northern and eastern limits of the plateau province have been studied in 

only a few places. Near the sixtj'-seventh parallel Schrader" describes the mountains to the north as falling off abruptly for 2,000 feet to the level of a plateau 

which has an altitude of 3,000 feet.

PLATEAU RANGES AND MOUNTAINS.

Dawson* lias described a number of well-defined ranges which lie within the 

Central Plateau region of British Columbia, under the name "Gold Ranges," but 

these die out near latitude 60", and north and west of them there are no important 

ranges in the province. Isolated peaks which rise above the plateau level are very 

common, and there are several minor ranges, such as the so-called Glacier Mountains, which rise about 2,000 feet above the plateau level in the upper part of the 

basin of the Forty-mile 6' River. These mountains have a northeast-southwest trend, 

and reach altitudes of 5,000 and 6,000 feet.

Spurr,rf in his studies of southwestern Alaska, described some mountains which 

may stand above the plateau. The southernmost, the Ahklun Mountains (PI. VII), 

stretch to the northeast from the shores of Bering Sea, forming the rugged 

peninsula which is cut out from the mainland by Kulukak Bay on the south and 

by the deep indentation at the mouth of the Kuskokwim on the north. These 

mountains have a width of about 60 miles, and are known to extend 200 miles 

inland. If they continue bej'ond this point they lie, between Lake Clark and the 

middle Kuskokwim, in a region which has not been explored. It may be that 

further studies will show them to be a southwestern extension of the Alaska

«Reconnaissance along the Cliandlar and Koyukuk rivers, Alaska: Twenty-first Ann, Kept. U. g. Geol. Survey, pt. 2, 

1300, p. 463.

fcDawson, G. M., On the later physiographical geology of the Rocky Mountain region in Canada: Trans. Royal Soc. 

Canada, vol. 8, sec. 4, 1890, pp. 4 and 5.

cSee Fortymile atlas sheet, U. S. Geol. Survey.

rt Reconnaissance in southwestern Alaska: Twentieth Ann. Kept. r. S. Geol. Survey, pt. 7, 1900, pp. 240-241.
U.S.GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 45 PL. XII

16fl° 162° 138° 154° ISO'

SKETCH MAP SHOWING DISTRTBTTTION OF FORESTS AND OF GLACIERS AND SNOW FIELDS

COMPILED BY ALFRED H.BROOKS 

Scale

0__________100_________200 _ 300 400 50O miles

1904

JUUUS BlCNACO.LITH.N Y
CENTRAL PLATEAU REGION. 39

Range. The higher peaks of the Ahklun Mountains reach altitudes of 7,000 and 

8,000 feet.

Spurr gave the name Kuskokwim Mountains to a low range which lies in the 

central Kuskokwim Valley, between latitude 61° and 62°. These may^ however, be 

a remnant of the plateau which has been reduced by erosion to a ridge-like form. 

The relief is probably not over 2,500 feet. On Herron's" map accompanying his 

report on the upper Kuskokwim basin are indicated some mountains which stretch 

in a northeasterly direction from latitude 63° 30' to about latitude 64° 30'. These 

Herron designates under the native names Sischu and Chitanatala mountains, and 

estimates the height of the former, which is the most easterly, at 1,500 to 2,000 

feet. The writer, who had a view of them from the western slope of the Alaska 

Range, is inclined to regard them as considerably higher. Though 50 to 70 miles 

away, they stood out clearly 1,000 to 1,500 feet above the plateau level, which is 

probably something lower than 3,000 feet. One peak was actually determined to 

be 4,000 feet by I). L. Reaburn, the topographer who accompanied the writer.

In the Seward Peninsula is a well-defined mountain range, which stands far 

above the general level of the upland. Its axis is shaped like a crescent, both 

points of which touch Bering Sea, while its arc lies 50 miles inland. Broad valley lowlands divide the range into three parts, each with a separate name. The 

first group on the west, the Kigluaik Mountains, has a maximum altitude of 4,700 

feet; the Bendeleben Mountains, the second group, reach 8,500 feet, while the 

Darby Mountains, the third group, are not over 2,000 feet high. Isolated peaks 

rising above the general upland are very common in the peninsula, but those 

already described and the York Mountains, lying in the western part of the peninsula, are the only considerable mountain masses.

Attention has been drawn to the more important mountain groups within the 

Central Plateau region. As more detailed surveys are carried out other highland 

masses will undoubtedly be discovered which must be classed with them. Single 

peaks elevated far above the plateau surface are very common, and in some cases 

have a linear arrangement which suggests that they are the remnant of a former 

mountain range.

COASTAL PLAINS.

As the Yukon Plateau approaches Bering Sea it gradually loses its distinctive 

features; the valleys broaden, the interstream areas grow smaller and lower, and, 

finally, 100 miles or more from tide water, the uplands end and the valley floors 

merge with the coastal plain which skirts the eastern shore of Bering Sea. This 

coastal plain, which is by far the largest of this region, is of low relief and about 

25,000 square miles in extent. It embraces the lower Kuskokwim and Yukon 

valleys as far north as Norton Sound, and for the most part is in the deltas of these 

two great rivers (PI. XXXIV).

Topographically, it is a level tract, here and there interrupted by hills and 

ridges, usually less than 1,000 feet in height, which form conspicuous features in the 

otherwise monotonous landscape. Such a range of hills stretches 100 miles northeastward from the central part of the Yukon Delta. The hills reach altitudes of

"Herron, J. S., Explorations in Alaska in 1899: War Department, Adjutant-General's Office, No. 31.
40 GEOGRAPHY AND GEOLOGY OF ALASKA.

2,000 feet and are believed to be of recent volcanic origin. The coastal plain slopes 

gently toward the sea from an inland margin which is probably less than 100 feet 

above tide water. In some places it is bordered inland by steep escarpments, while 

at other points it merges into the valley floors of the streams.

Watercourses meander sluggishly across the plain, their floors but slightly 

incised below its general level. During the spring freshets these overflow their 

banks, seeking new channels and silting- up old ones, and a large part of the plain 

becomes a swamp, with an ill-defined drainage and dotted with lakes. There are no 

trees nothing to break the monotony of the landscape but small bunches of willows.

Among the other and lesser coastal plains of this province, that of the Nushagak 

River region is worthy of note. As far as can be learned from the meager accounts, 

this lowland stretches inland from Bristol Bay, embracing the lower courses of the 

Nushagak and Kvichak rivers and the region lying adjacent to the lower end of 

Iliamna Lake. Smaller coastal plains are also found along both the southern and 

northern shores of the Seward Peninsula.

INTERIOR LOWLANDS.

Besides these coastal features there are also large lowland tracts in the inland 

parts of the province. The largest of these is the so-called Yukon Flats, a depressed 

area at the great bend of the middle Yukon, about 200 miles long and 40 to 100 

miles wide, which is nearly bisected by the Arctic Circle. It has an altitude of about 

500 feet and, as its name implies, is a monotonous lowland throughout its extent. 

Broadly speaking, its outline is rectangular, but its periphen^ is irregular. The 

upland which surrounds the flat is distinctly of. the plateau type; in some places it 

falls off precipitous]y to the lowland; in others, it is separated from the lowland 

by hills of less relief, which make the transition more gradual. At its southern end 

the lowland ends abruptly at a rocky escarpment, which rises to the flat-topped hills 

of the plateau.

This lowland forms part of the valleys of the Yukon River and its tributary, 

the Porcupine. Through it the Yukon meanders in numerous channels, broadening 

out in places to probably 20 miles; and where it is joined by large tributaries 

the lowland extends up their valleys for a greater or less distance (see PI. 

XIV, A).

Another depressed area, similar to the Yukon Flats, lies between latitude 

63° and 64° in the Kuskokwim drainage basin. This, which may be called the 

upper Kuskokwim Flat, is essentially an area of low relief, through which the 

drainage channels meander with great irregularity. As it lies in part in an 

unmapped region, its limits can not be given in detail, but it may be said to 

extend eastward to the base of the Alaska Range, while to the north it is 

coextensive with the valley lowland of the lower Tanana, and on the west it is 

bounded by an escarpment. The southern boundary has not yet been determined. 

Near the base of the Alaska Range, on the east, the flat is deeply buried in a 

heavy deposit of gravel, forming a piedmont plateau (PI. XXXII, A), which 

slopes westerly until it finally merges with the silt deposits of the central part 

of the flat.
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER MO. 45 PL. XIII

UPLAND OF SEWARD PENINSULA NEAR HOT SPRINGS.
U. 8. GEOLOGICAL SURVEY

A NORTHERN MARGIN OF YUKON FIATS IN CHANDLAR VALLEY.

B. NORTHERN MARGIN OF COPPER RIVER PLATEAU.
CENTRAL PLATEAU REGION. ' 41 

SUMMARY.

The great interior upland, which has been designated the Central Plateau region, 

stretches northward from the inland ranges of the Pacific Mountain system to the 

foothills of the Rocky Mountain system. Into this upland the drainage courses 

have incised channels varying from 1,000 to 4,000 feet in depth, giving a very 

irregular topography. The summits of the unreduced hills and ridges, lying 

between the waterways, mark a gently rolling plain which slopes toward the north 

and west. Viewed from one of these summits, the sky liue is characterized by 

marked regularity, and is broken only here and there by highland masses, which 

rise above the general level and, in some instances, are of sufficient extent and 

altitude to be called ranges. There are also within this province a number of large 

lowland areas, which stand from 1,000 to 1,500 feet below the upland.

This Central Plateau region is coextensive with the plateau region of British 

Columbia, and can be regarded as belonging to the same physiographic province 

as the Great Basin region of the western United States. The history of its 

development will be discussed in another part of this paper, but a clearer conception of its form may be obtained from the statement that it is due to erosion 

and is not a constructive plain of deposition. The land mass which now constitutes the plateau stood formerly at a lower altitude, and its surface, except for 

some unreduced areas which now form the mountains and solitan^ peaks of the 

upland, was gradually reduced by subaerial erosion to a seaward-sloping plain. 

After reduction, differential elevation took place, and as the activity of the streams 

and rivers was renewed, they began channeling out their present valleys. In this 

manner was evolved the present topography of flat-topped summits, which mark 

the former plain of erosion, and which are separated by the more recently carved 

drainage channels.

The plateau province is, as a rule, well forested, though the trees are not of 

great size. On the Seward Peninsula spruce and cottonwood are limited to the 

eastern end. Spruce forests reach the coast along the eastern shore of Norton Bay, 

but the timber line strikes inland, crosses the Yukon and Kuskokwim near the head 

of their deltas, and again reaches the coast near the head of Bristol Bay. On the 

seaward side of this line nothing but stunted willow is found, and that only in the 

creek and valley bottoms (PI. XIL).

Above the delta the banks of the Yukon and its larger tributaries, the Koyukuk, 

Tanana, Porcupine, and White rivers, are usually well forested (PI. XV, B). The 

upper limit of timber varies according to local conditions, but shows a decline 

toward the northern side of the basin. On the White and upper Tanana the limit 

of heavy spruce growth is about 3,500 feet, while on the Koyukuk it is less than 

3.000 feet.

The chief varieties of trees are the spruce (which is most abundant), white birch, 

poplar, and aspen (usually called "cottonwood" by miners and prospectors). There 

are also many varieties of willow and several of alder; and tamarack has been found 

on the lower Tanana and upper Kuskokwim.

Sweeping generalizations have been made by some writers regarding the 

important timber resources of the Yukon Valley, but these have not been borne out 

by the observations of the writer, who has traveled extensively throughout this
42 GEOGRAPHY AND GEOLOGY OF ALASKA.

region. In the valley lowlands of the Yukon and tributary streams it is not 

uncommon to find small groups of trees which will measure 2 and 2£ feet in 

diameter at the butt. These, however, are exceptional, for most of the trees are 

only from 5 to 12 inches. The timber with proper protection would be ample for 

local use, but has no value for export. Large quantities are annually destroyed by 

fire, for which the natives must largely be held responsible. The writer has 

remarked again and again that the Alaska Indians are utterly careless about forest 

fires. It seems probable that they deliberately burn over large tracts in order to 

somewhat reduce the insect pest. That this indifference to forest fires was not 

learned of the white men is shown by the fact that many tracts are found which 

must have been burned over long before the appearance of any foreigner.

ROCKY MOUNTAIN SYSTEM. 

GENERAL DESCRIPTION.

The name Rocky Mountain system has long been applied to the easterly 

group of ranges forming the great cordillera of western North America. The 

limits of this s3T stem are in most cases sharply drawn, for it is bounded on the 

east by the low plateau region usually known as the Great Plains and on the 

west by the elevated plateau province termed the Great Basin.

The Kooky Mountain system continues northwestward from the western 

United States through Canada nearly to the Arctic Ocean. South of Mackenzie 

Bay it turns almost at right angles, crosses the international boundary (the one 

hundred and forty-first meridian) in about latitude 68 C , and continues,.in a direction 

a little south of west, across northern Alaska to the Arctic Ocean. (PL II.)

In the United States the Rocky Mountain sj'stem is complex and includes 

several high ranges whose axes are in general parallel, together with numerous 

transverse lines of height. This complexity is retained nearly to the northern 

boundary of British Columbia (latitude 60°), where the system" is composed of 

several approximately parallel ranges 3,000 to 4,000 feet in height. These are 

not persistent for any great distance, but give place toward the north to other 

parallel ranges, which die away northward. Thus the axes of the ranges have 

an echelon character which, as far as known, holds northward to the international 

boundary. The Northern Rockies of Canada have not been extensively explored, 

however, and little is known of them bej'ond the fact that they constitute a mountainous belt about 50 miles wide which stretches northward from the Liard River 

nearl}- to the Arctic coast, and forms in general the watershed between the Yukon 

on the west and the Mackenzie on the east. McConnell,* who crossed this divide at 

the Peel River portage, in about latitude 67°, describes two distinct ranges, about 

4,000 feet in altitude and flanked on either side by high plateaus. West of the 

international boundary the mountains increase in both height and complexity to 

about the one hundred and fifty-first meridian, and from there to the Arctic Ocean 

decrease in altitude.

allcGonnell R. G., Report on an exploration in the Yukon and Mackenzie basins, N. W. T.: Ann. Kept. Geol. Nat. 

Hist. Survey Canada, vol. 4,1890, pp. 8D and 9D. 

6Ibid., p 119D.
ROCKY MOUNTAIN SYSTEM. 43

The name " Endicott Mountains" was first given by Lieutenant Alien" to a 

high range of mountains seen by him toward the north during his exploration of 

the Koyukuk. Schrader,'' who made the first detailed studies of the g'eology and 

geography of these mountains, has accepted this name and extended its application 

to include all of the ranges which go to make up the Rocky Mountain system of 

northern Alaska. The great mountain mass which extends across northern Alaska 

from the Arctic Ocean to the international boundary can, therefore, be designated 

the Endicott Mountains, and this term may be regarded as synonymous with the 

Rocky Mountain system of Alaska.

As much of this system has not been surveyed and hardly explored, the 

ranges composing it can not be described in the same detail as those of the 

Pacific highland belt. As far as known, this system always embraces at least 

two distinct ranges. The topography is rugged and the transverse valleys are 

sharply cut. The longitudinal valleys are broad, with gentle slopes, some of 

them of a basin type, like that of Noatak River, which divides the system into different ranges. In the eastern part the southern and higher range forms the 

watershed between the Yukon and Arctic waters. To the west the waterways 

of the two drainage areas interlock, and the watersheds are very irregular.

The system as a whole is sharply defined. It is bounded on the south by 

the Central Plateau and on the north by the Arctic Slope region. Its southern 

limit, at the international boundary, lies about 100 miles north of the Porcupine 

River, and extends in a southwesterly direction, parallel to the general courses of 

the Yukon and Porcupine rivers, to its intersection with the sixty-seventh parallel of latitude, which it follows approximately to Kotzebue Sound. (PI. VII.)

The southern slope of the mountains rises rather abruptly from the upland 

region of the Koyukuk River, which belongs to the plateau province. The line 

between the uplands and the mountains, where it has been mapped, is irregular, 

at one point bending southward to include a spur, at another forming a deep 

reentrant into the front of the range. On the Arctic slope the descent to a low 

plateau region is still more abrupt. For long stretches the mountains present a 

bold escarpment to the north, and the sharp transition from the smooth, mosscovered plateau to the bold, rugged mountains is very striking (PI. XXIX, B). 

Where the drainage channels leave the mountains the frontal scarp is broken by 

indentations, and if the river is a large one, like the Colville, this indentation 

extends into the mountains for many miles. The seaward slope of these ranges 

trends southwestward by a series of reentrants of an echelon type.

EASTERN PART OF ROCKY MOUNTAIN SYSTEM.

Near the international boundary the mountainous belt, which is upward of 

100 miles in width and contains peaks as high as 7,000 or 8,000 feet, is divided 

on the maps into the British Mountains on the north and the Davidson Mountains, 

which are higher, on the south. But the meager notes published by Mr. J. H.

a Alien, H. T., An expedition to the Copper, Tanana, and Koyukuk rivers, Alaska, 1885. Washington, 1887.

SSchrader, F. C., Reconnaissance in northern Alaska: Prof. Paper U. S. Geol. Survey So. 20, 1904. A preliminary 

statement is contained in an article entitled "Geological section of the Rocky Mountains ni northern Alaska:" Bull. 

Geol. Soc. America, vol. 13,1902. pp. 233-252.
44 GEOGKAPHy AND GEOLOGY OF ALASKA.

Turner," who crossed this region along the one hundred and forty-first meridian, 

in connection with the boundary survey, would point to the conclusion that there 

are a number of ranges forming a complex mountain mass, but broken by broad, 

low gaps.

While no actual surveys have been made of the eastern part of this mountain 

belt, explorers who have visited the Mackenzie Kiver and the north coast of Alaska 

have not hesitated to name the mountains which they could see to the south and west. 

Thus the names Gilbert, Davis, Buckland. and Richardson appear on charts to 

designate various parts of one general range which forms the northern part of the 

system between the international boundary and the Mackenzie River.

West of the boundary (see PI. VII) the northern front is made up of a number 

of minor ranges, whose axes have an echelon relation. The British Mountains, for 

instance, stretch as far west as the one hundred and forty-second meridian and break 

off abruptly to the Arctic lowland; then the range is continued westward by the 

Rornanzof Mountains, which in turn end abruptly near the one hundred and fortysixth degree of longitude; a deep reentrant carries the mountain front back to 

the Franklin Mountains, which are believed to continue to about the one hundred 

and forty-eighth meridian, where they also end abruptly; and the front again 

retreats inland by another reentrant which carries it into an unexplored region. 

These ranges which mark the northern limit of the system probably do not reach 

altitudes over 3,000 or 4,000 feet.

WESTERN FART OF UOCKY MOUNTAIN SYSTEM.

Little is known of the westward extension of the chain as far as the one hundred 

and fifty-second meridian, except that it is a high, rugged mass made up of two or 

more ranges. At this point, however, somewhat detailed studies have been made by 

Schrader, who describes the Endicott Mountains (as he terms them) as made up of 

two more or less distinct ranges, separated by a less elevated, though also mountainous belt. The northern range reaches altitudes of something over 6,000 feet, and 

the southern of a little less than 5,000 feet: the whole embracing a rugged mountain 

mass about 80 miles in width.

To the west the two ranges described diverge and are separated by a depressed 

area which contains the headwaters of the Colville and Noatak rivers. The northern 

range, named the De Long Mountains by Stoney,* stretches almost due west, 

decreasing in height north of the Noatak River Valley and dying out in the highlands 

of the peninsula which terminates westerly in Cape Beaufort. The highest altitudes 

in those mountains are probably 3,000 to 4,000 feet.

The southern range, to which Stoney gave the name "Baird Mountains," 0 

bends slightly to the south at the one hundred and fifty-third meridian, and then, 

extending westward with decreasing altitude, forms the mountainous divide between 

the Noatak and Kobuk rivers and appears to end abruptly close to the sea north of 

Kotzebue Sound. The lower valley of the Noatak lies transverse to these mouno Ann. Kept. U. S. Coast and Geodetic Survey for 1891, pt. 1, p. 88.

6 Stoney, G. M., Naval Explorations in Alaska: United States Naval Institute, Annapolis, 1900.

See, also, Mendenhall, W. 0., A reconnaissance from Kotzebue Sound to Fort Hamliu: Prof. Paper U. S. Geol. Survey 

No. 10, 1902.

"On some maps the name "Jade Mountains" is used to designate this range.
EOCKY MOUNTAIN SYSTEM. 45

tains and cuts completely across them. While the elevation of the range averages 

less than 3,000 feet, some of the peaks near the coast may reach altitudes of 4,000 

feet.

The Waring Mountains, also with an east-west axis, are denned on the north by 

the Kobuk Valley and on the south by the Selawik Valley. They probably belong 

to the Rocky Mountain system, though their low altitude of 1,500 to 2,500 feet suggests that they may form part of the Central Plateau province. Less denned are 

the highlands named by Stoney the Schwatka, Melville, and Lockwood mountains, 

which trend in various directions, and would seem to be transverse lines of height 

and watersheds rather than distinct ranges."

The Rocky Mountain system west of the one hundred and tif ty-second meridian, 

as far as its geography has been determined, would thus seem to embrace two fairly 

well-defined ranges which extend with decreasing altitude westward to the Arctic 

Ocean.

SUMMARY OF KOOKY MOUNTAIN SYSTEM.

The group of ranges termed the Rocky Mountain system, stretching northwestward through Canada, loses much of its relief and complexity as it approaches the 

Arctic Ocean, but after bending to the southwest and entering Alaska, again becomes 

a complex mass. It is continued southwestward as a great trails-Alaska chain to 

which the name Endicott Mountains has been applied. Near the one hundred and 

fifty-third meridian it splits into two diverging ranges which extend westward to the 

Arctic Ocean. On the south the mountains are bounded by the interior plateau 

from which they are not always sharply differentiated, but. the lines of demarcation 

from the Arctic Slope region are well defined.

Schrader* has called attention to the plateau character of the Endicott Mountains 

mass. Viewed from altitudes of 6,000 feet the mountains show a remarkably even 

sky line and strongly suggest that they have been carved from a former plateau 

(PL XXIX, A).

The southern slopes of these ranges are dotted with a moderate growth of spruce, 

interspersed with birch and a little aspen and poplar up to an altitude of 1,000 s to 

2,000 d feet (PI. XII).

The valley of the Kobuk' River is well timbered with spruce, birch, and cottonwood. The growth is thickest in a belt a mile or two wide, lying adjacent to the 

river bank/ beyond which it is scattered over the valley slopes and in all the sheltered tributary gulches and valleys up to an altitude of about 1,000 feet. StoneyS' 

makes mention of a spruce cut on the upper Kobuk which was 50 feet long and 16 

inches in diameter at the butt. The spruce, as a rule, averages from 5 to 10 inches 

in diameter, but 12-inch trees are not uncommon. As elsewhere in this northern 

region, several varieties of willow and alder occur above the limit of spruce timber.

«See map in Stoney's report.

I'Reconnaissance along the Cliandlar and Koyukuk rivers, Alaska: Twenty-first Ann. Rept. U. S. Geol. Survey, 

pt. 2. 1900, p. 463. Geological section of tlie Rocky Mountains in northern Alaska: Bull. Geol. Soe. of America, vol. 13, 

1902, p. 236. Prof. Paper U. S. Geol. Survey No. 20, 1904, pp. 42-43.

cSchrader, F. C., Recent work of the United States Geological Survey in Alaska: Bull. Am. Geog. Soc., vol. 34,1902, p. 16.

(JTurner, J. H., Alaskaii boundary survey: Nat. Geog. Mag., vol. 4, 1892, p. 196.

«Bull. American Geog. Soc., vol. 34, p. 9.

/Information furnished by Mr. L. M. Priiidle, who spent a year on the Kobuk.

a Naval Explorations in Alaska, U. S. Naval Institute, 1900, p. 81.

17211 No. 45 06 4
46 GEOGRAPHY AND GEOLOGY OF ALASKA.

The lower valley of the Noatak" is forested scantily with spruce and cottonwood, 

and above, where it is crossed by the one hundred and sixty-second meridian, is 

almost devoid of timber, except a little scattered spruce and stunted willow.

Forests are almost entirely absent on the Arctic slope of the mountains. Along 

the stream bottoms is a stunted growth of willow which yields a limited supply of 

fuel for cooking. Some spruce is reported on the upper waters of the Turner 

River, which flows into the Arctic near the boundary.

ARCTIC SLOPE REGION 

INTRODUCTION.

Near the international boundary the northern face of the Rocky Mountain 

ranges rises almost directly from the sea, with only a few miles of low coastal plain 

between it and the Arctic Ocean (see PI. XXIX, B). To the west the coast line 

bends northward and the mountain front southward, thus widening out this coastal 

belt to upward of 150 miles near the one hundred and fifty-sixth meridian. At 

Point Barrow the coast line makes a right-angled bend to the southwest, and the 

coastal belt rapidly narrows again, so that near the one hundred and sixty-third 

meridian the northern front once more abuts almost directly on the sea.

This province, which embraces both plateaus and coastal plains, has here been 

termed the "Arctic Slope province." It corresponds physiographic-ally with the 

Great Plains region of the western United States and Canada (PI. II).

SUBDIVISIONS OF THTC PROVINCE.

Schrader, 6 who has studied this province along the valley of the Colville River, 

divides it into two subprovinces, the Anaktuvuk Plateau and the Coastal Plain. 

The plateau lies immediately adjacent to the mountain front, where it has a height 

of about 6 2,500 feet. Thence it stretches northward, retaining its character as a 

rolling upland and sloping gently toward the Arctic for about 80 miles from the 

mountains, where, according to Schrader, the Coastal Plain begins. He makes 

no mention of any sharp demarcation between the plateau and plain, and it would 

be inferred that there was a gradual transition between the two topographic forms, 

their difference lying in the fact that the plateau is gently rolling while the plain 

is absolutely flat. In the account of the development of the topography it will be 

shown that the two types differ genetically. The higher plateau is an uplifted 

eroded surface, while the lower is a constructional form, being built up of horizontally stratified sediment (p. 279).

In many places a true coastal plain standing but a few feet above sea level intervenes between the lower plateau and the Arctic. This is a flat, featureless plain, its 

monotony broken only by an occasional flat-topped hill the remnant of the lower 

plateau. In some places the coastal plain is entirely wanting, and the base of the 

escarpment which marks the northern limit of the lower plateau is washed by waves

nMcLenegan, S. B., Exploration of the Noatak River, Alaska: Rept. of the Cruise of the Revenue-Cutter Steamer 

Corwin, 1885, pp. 53-80.

li A reconnaissance in northern Alaska: Prof. 1'aper U. S. tteol. Survey No. 20, 1904, pp. 45-46.

f Mr. Collier's recent work shows that this plateau is recognizable at Cape Lisburne at an altitude of about 2,000 feet.
DRAINAGE. 47

of the Arctic, in others it broadens out to 8 or 10 miles; and where the escarpment 

is broken by the mouths of large rivers the coastal plain merges with the valley 

floors and is characterized by an undeveloped drainage system, extensive marshes, 

and innumerable small lakes and ponds. The coast line includes stretches of long, 

straight, sandy beaches, broken here and there by large lagoons.

Little is known of the Arctic Slope region, except that portion immediately 

adjacent to the coast and to Schrader's route of travel, but the few scattered observations made by exploring expeditions which have skirted the coast of the Polar Sea 

lead to the belief that the geographic features described are, in general, persistent 

throughout the province.

SUMMARY OF ARCTIC SLOPE REGION.

The Arctic Slope region is then a province of comparatively low topographic 

relief which stretches across northern Alaska, bounded on the south by the front 

ranges of the Rockies and on the north by the Arctic Ocean. Its southern portion 

is a high, rolling plateau sloping to the north and then falling by an escarpment to 

a lower plateau, which also dips to the north and breaks off to the coastal plain by 

a low escarpment.

The province is a part of the great tundra belt that encircles the Polar Sea, 

and is entirely without timber. The stream valleys crossing the province, however, 

contain considerable willow, which becomes more and more stunted toward the 

Arctic Ocean (PI. XII). The Eskimos depend on the limited supply of driftwood for 

fuel when on the coast, and on the willow for their inland excursions.

URAISTAGE.

INTRODUCTION.

When exploration and settlement, for a long time confined to the seaboard, at 

last began to push inland, the drainage channels naturally afforded the easiest lines 

of approach. Along the rivers the pioneer could transport necessary supplies in 

crude rafts or boats built of the timber which grew on the banks; arid, later on, the 

steamboat succeeded craft propelled by hand. It was not until beasts of burden 

were introduced that extensive land journeys could be undertaken. At first these, 

too, followed valleys; but later passes through the mountains were discovered and 

trails were established, to be followed l>y wagon roads and these in turn by railways.

Not only has the drainage system determined the avenues of approach, but the 

valleys have yielded nearly all the placer gold and the streams have provided the 

water power so important to economic exploitation of the ore bodies. Moreover, 

the best timber and most of the arable land is found on the river banks and along 

the valley floors.

In short, the water courses are and have been to man the most important physical 

features of inland Alaska, and for this reason and because they are better known 

they will be described more in detail than the mountains and plateaus. Even at the 

risk of repetition, a sketch of the salient features of the extensive drainage system 

will be presented before the reader becomes lost in the maze of detail.
 48 GEOGRAPHY AND GEOLOGY OF ALASKA.

GENERAL FEATURES.

In Alaska the drainage belongs to three divisions: its southern part, about onefifth of its area, drains to the Pacific Ocean; the great interior region, covering 

nearly one-half of all Alaska, drains into Bering Sea; and the rest of the territory, 

its northern part, drains to the Arctic Ocean.

The Yukon, flowing into Bering Sea, is the master stream (see PI. XXXIV). 

This mighty river, the fifth in size of the North American Continent, springs from 

headwaters in British Columbia, far to the southeast of Alaska, where it fights for 

supremacy on the one hand with water courses flowing into the Pacific, and on the 

other with those belonging to the Arctic watershed. The Yukon flows northwest as 

far as the Arctic; Circle, then sweeps around to the southwest, and finally pours its 

great volume of muddy waters into Boring Sea, over 2,000 miles from the source of 

its longest tributary. Its basin is outlined in a general way by the boundaries of the 

Central Plateau province, of which its valle}' occupies nearly the medial line, and 

makes with it the same great bend to the southwest, parallel to a similar swing of 

the two mountain systems on the north and south. The Kuskokwim, also emptying 

into Bering Sea, is second in size only to the Yukon among Alaska rivers. Its source 

lies on the western slope of the Alaska Range, and its course is southwesterly, 

generally parallel to the Yukon.

The Pacific drainage embraces two classes of rivers: first, those whose catchment 

basins lie entirely within the coastal zone of mountains; and, second, those which 

flow from sources in the interior beyond the coastal barrier and traverse the mountains on their way to the sea. Of the first the Sushitna and Copper, and of the 

second the Alsek, Taku, and Stikine are the most prominent examples.

The Arctic Ocean receives waters from a small part of the plateau province 

through short rivers draining the northern part of the Seward Peninsula, and 

larger ones flowing into Kotzebue Sound. The larger part of the Arctic drainage is 

derived from interior valleys and northern slopes of the Rocky Mountain ranges. 

The Noatak and the Kobuk, which are bounded both north and south by mountains 

of the northern system, belong to the first of these classes; and northerly flowing 

waterways which are fed by streams from the seaward slope of the Rockies belong 

to the second. The Colville, the largest of these rivers, properly belongs to both 

classes, for its source lies well within the front ranges, through which it passes in a 

narrow valley.

PACIFIC DRAINAGE.

The larger rivers of the Pacific drainage have southwesterly courses, and many 

of them flow from sources in the Pacific Mountain system. In southeastern Alaska 

there are three large rivers which rise in the interior plateau region: the Stikine and 

Taku traverse the Coast Range to reach the sea, while the Chilkat reaches the coast 

through the longitudinal valley that separates the St. Elias and Coast ranges.

STIKINE BASIN.

The Stikine River, which finds its outlet near latitude 57°, rises in British 

Columbia inland of the Coast Range, where its headwaters interlock with those of 

the Liard, tributary to the Mackenzie, and with streams flowing to the Yukon. In
PACIFIC DRAINAGE. 49

other words, this divide, the most important in the province, distributes waters to three 

.great systems: the Liard, flowing northeastward, traverses the Rocky Mountains 

and joins the Mackenzie, which flows into the Arctic; the Stikine, with a southerly 

course, reaches the Pacific through the Coast Range; and the Yukon waters flow to 

the northwest, on a long journey to Bering Sea.

Along the upper Stikine a the valley is rather broad, with a floor 3,000 to 4,000 

feet below the inland plateau level; but in crossing the Coast Range it narrows 

between abrupt walls 1,000 to 8,000 feet high.

At the head of the delta the river emerges from the Little Canyon, which is 

about three-fifths of a mile long and 50 yards wide, and is bounded by rock cliffs 200 

to 300 feet high. Eight miles above is the Kloochman Canyon, 300 feet wide. 

Above Telegraph Creek a constricted portion of the valley, 30 or 40 miles long, has 

received the name Great Canyon.

Near its source the river flows from east to west, then it gradual!}* turns 

southward and traverses the mountains with an almost due southerly course. 

Twenty miles from the coast the river bends sharply to the west again, and 

finally reaches salt water at the head of the Stikine Sound, an arm of the sea 

which is outlined by promontories of the mainland and by several islands. The 

delta of the river is the silted-up inland extension of this same channel.

On its way through the mountains the Stikine receives several large glaciers. 

Most of its tributaries are in British Columbia, inland of the Coast Range. Of 

these the Iskut, confluent from the cast near the inland front of the range, is 

the largest. According to Dawson, the mouth of Telegraph Creek, which is 

practically at the head of steamboat navigation, is 130 miles from arid 540 feet 

above tide water. The mean velocity of the current to this point is about 5 

miles per hour.

The Stikine Valley has long been a route of communication between the 

natives of the coast and of the interior. The white trader made use of the same 

waterway, and he "was followed by the miner and prospector. In the early 

seventies, during the height of the excitement attendant upon the discovery and 

development of the Cassiar gold district, several thousand men made their way 

inland by this route, and during the Klondike excitement of 1898 it was one of 

the many routes by which the gold seekers attempted to reach Dawson.

TAKTJ BASIN.

The Taku River rises in the Central Plateau region of British Columbia, and 

flows southwest across the Coast Range to salt water at the head of Taku Inlet, 

a deep indentation of the southeastern coast of Alaska near latitude 58° 30'. Its 

northern waterways interlock with the streams flowing into Lake Atlin and those 

tributary to the Teslin, both belonging to the Yukon drainage, and its southern 

are opposed to tributaries of the Stikine.

The upper Taku 6 and its tributaries flow in broad, open valleys, whose floors 

are about 3,000 to 4,000 feet above sea level and 2,000 feet below the level of

« Dawson, G. M., Report on an exploration in the Yukon district and British Columbia: Ann. Rept. Geol. Ntt. Hist. 

Survey Canada, new series, vol. 3, pt. 1, pp. 46B-51B.

SHayes, C. W., An expedition through the Yukon district: Nat. Geog. Mag., vol. 4, 1893, pp. 117-162.
50 GEOGRAPHY AND GEOLOGY OF ALASKA.

the plateau. Up to 1,500 feet the valley walls are steep and then slope gently up 

to the level of the plateau. The valley of the lower Taku, which, according to 

Hayes, is an inland continuation of Taku Inlet, has abrupt sides, sometimes almost 

perpendicular for 3,000 to 4,000 feet.

The river is swift, and its waters are heavily laden with sediments. It is 

uunavig'able for steamers, but small boats have been taken up to the south fork, 

whence an Indian portage trail of 80 miles leads to Lake Teslin. This has been 

used as a route to the interior by an occasional party of prospectors, but never 

extensively, even during the Klondike excitement.

CHILKAT BASIN.

The Chilkat" River has its source on the Canadian side of the international 

boundary, in the coastal mountain province, and flowing in a southeasterly direction, through a depression which separates the northern part of the St. Elias 

Range from the Coast Range, reaches the coast at the head of Chilkat Inlet, a 

western arm of Lynn Canal. Its headwaters interlock with those of the Alsek, 

and its largest northern tributary, as yet unnamed, has its source in a glacier 

which drains partly into the Lewes River.

The upper course of the Chilkat lies through a constricted valleA-, whose 

walls rise steeply for 1,000 to 1,500 feet and then slope more gradually to the 

mountain summits. As the lower valley is merely an inland extension of the 

tidal fiord that has been filled up by alluvial deposits, its walls merge with 

the slopes of the inlet.

The valley slopes are broken by benches and terraces, of which the highest 

observed have an altitude of 1,000 to 1,500 feet. In the report cited these 

stream benches were considered by the writer to give evidence of recent uplift, 

but he now regards them as chiefly of glacial origin.

The Chilkat basin lies, for the most part, in high mountains, where the 

relief is from 5,000 to 7,000 feet; while the divide which separates its headwaters from Alsek drainage is about 3,000 feet above tide. To within 30 miles 

of the coast the river flows in one stream, then it breaks up into numerous 

channels meandering over a wide, gravel-filled valley bottom. This results in a 

broad delta which occupies the head of the inlet and is rapidly encroaching 

upon it with a seaward extension of silt flats which are uncovered at low tide. 

The river is turbulent and silt-laden, and descends probably 400 or 500 feet in the 

lower 70 miles of its course. It has been navigated, with difficulty, by a small 

steamer as far as Klukwan, an Indian village, about 20 miles from tide water.

The Takhin and Klehini, the largest tributaries of the Chilkat, are both 

affluent from the west within 10 miles of tide water. They have their sources in 

glaciers and receive numerous glacial tributaries from the slopes of the St. Elias 

Range. A number of glaciers also find outlet in the Chilkat itself.

Along the Chilkat and Klehini v&lleys routes of travel into the interior were 

established by the coast Indians long before the coming of the white man. 

After white traders reached the coast, the Chilkat Indiana occupying the region

a Brooks, A. H., Reconnaissance from Pyramid Harbor to Eagle City, Alaska: Twenty-first Ann. Kept. U. S. Geol. Survey, pt. 2, 1900, pp. 347 and 348.
PACIFIC DKAINAGE. 51

about the head of Lynn Canal became the middlemen, through whom the natives 

of the interior secured the products of civilization. Their trading expeditions 

involved a journey of several hundred miles across the divide at the head of the 

Chilkat River and thence westward along the northern base of the St. Elias 

Range to the natives of the White River. Jack Dalton, an Alaskan pioneer 

trader, used this old Indian route during the early Klondike excitement in 

establishing a trail from Pyramid Harbor up the Chilkat and Klehini rivers and 

across the divide to the interior. It was at first extensively used for driving 

cattle to the Yukon, as it passes through an exceptionally good grazing country, 

but since the building of the White Pass railway this trail has been almost 

abandoned.

SMALL WATEBCOUBSES OF SOUTHEASTERN ALASKA.

The Chilkat, Taku, and Stikine are the only large rivers in southeastern Alaska, 

but there arc a number of smaller ones, whose drainage basins lie in the Coast Range. 

The Taiya River rises in a glacier close to the Chilkoot Pass, and, flowing southwesterly through a rather broad valley, empties into the head of Lynn Canal. The 

Chilkoot Pass is 3,100 feet above the sea, and the adjacent peaks of the Coast Range 

reach 7,000 and 8,000 feet. About 4 miles east of the Taiya River the Skagway 

River is tributary to Lynn Canal. The lower 20 miles of its course is directed 

southwesterly through a broad valley, upon which it debouches by a sharp curve 

out of a narrow canyon from the southeast. At this bend it is joined by a small 

tributary which has its origin at an altitude of about 2,800 feet in the White Pass, 

5 miles to the northwest.

The Chilkoot and White passes separate the affluents of Bering Sea on the 

north from the Pacific drainage on the south. Nowhere in the entire coastal 

mountain belt do the inland streams find source so near the coast, for the Lewes 

River, a tributary of the Yukon, springs from a small lake beyond the Chilkoot 

Pass, not 25 miles from tide water. This natural inland route of travel was in use 

by the coastal natives when white men first came; it was adopted by the Yukon 

pioneers, and' the beginning of the Klondike excitement found it well established. 

Thousands of gold seekers transported their equipment with heart-breaking toil 

across this barrier in 1897 and 1898. In the latter year a trail was established across 

the White Pass, which soon developed into a wagon road, and was in time followed 

by the railroad. Upon the opening of the railway in 1899 all other routes across 

the Coast Range were practically abandoned.

The Unuk River enters Burroughs Bay, an arm of the sea, in latitude 56°, and 

its lower valley is a silted-up portion of the bay. As far as known, a its source must 

lie near the eastern slope of the Coast Range. It is not navigable for steamers, but 

prospectors have ascended it in small boats for 20 or 30 miles. The grade of the 

stream is steep arid the current swift. Mining interests which have been developed 

in the Unuk basin have led to the construction of a wagon road for some distance 

inland.

The seaward drainage of the Coast Range finds outlet through many small 

streams into the embayments and channels of the coast line. The gradients of

a Brooks, A. H., The Ketchikan mining district: Prof. Paper U. S. Geol. Survey No. 1,1902, pp. 86 and 37.
52 GEOGBAPHY AND GEOLOGY OF ALASKA.

the watercourses are, as a rule, steep, and the streams, which flow transverse to the 

axis of the range, are torrential. Ice has sculptured the mountains, leaving in its 

wake many cirques whose floors slope to sea level, or below it, through U-shaped 

valleys.

There are also many smaller amphitheaters far above sea level, in which streams 

have incised sharp V-shaped valleys below the old glaciated floor. Some of the 

glacial channels are of the true " hanging valley" type, which end abruptly, often 

breaking off in cliffs over which the streams tumble in beautiful waterfalls on their 

way to the sea.

Much of the precipitation on the higher mountains is in the form of snow, 

and of the resulting glaciers some of the larger debouch directly into the sea, 

while the smaller discharge into the rivers. The drainage of the Alexander Archipelago is usually carried to the sea by small streams. Here, except on Baranof 

Island, there are no glaciers, but the U-shaped vallej^s, as well as other phenomena, give abundant evidence of former ice erosion.

CROSS SOUND TO CAPK 1'AIRWEATHEK.

For 100 miles west of Cross Sound the St. Elias Range presents a bold, 

unbroken front to the ocean. In this stretch small streams fed by the perennial 

snows of the upper heights here and there tumble down the precipitous slope, 

often almost sheer to salt water. Much of the precipitation is carried down as 

snow and ice in the numerous glaciers, some of which discharge directly into 

the sea. The bare rocks, vast expanses of snow arid ice, precipitous peaks, and 

crests rising almost sheer 10,000 to 12,000 feet above the sea, afford a landscape 

hardly equaled in the world for its grandeur.

ALSEK BASIN.

West of Cape Fairweather an abrupt recession of the mountain front marks 

the eastern margin of the broad delta of the Alsek River, which, though as yet 

unsurveyed, is believed to have a width of nearly 40 miles. The small bight in 

the coast line at the delta front is called Dry Bay. The recession of the mountains continues inland as the eastern wall of the Alsek Valley, a broad depression 

transverse to the St. Elias Range, and the only break in the coastal barrier 

between the Chilkat and Copper rivers. The Alsek and its tributaries rise in the 

inland plateau province in Canadian territory. North of the range the drainage 

system is characterized by broad valleys which have gently sloping walls, and 

sometimes widen out into gravel-floored basins. These are often connected by 

constricted channels with steep rock walls, veritable canyons, in fact. The topographic evidence all points toward recent changes and readjustment of this 

drainage system (see pp. 284, 285).

Little is known of the Alsek River within the mountains, but it is said to 

fork about 40 miles from the sea. a The eastern branch, called the Tatshenshini 

River, rises near the headwaters of the Chilkat, flows northwesterly through a 

succession of valley basins and rock canyons to about the one hundred and thirtya Brooks, A. H., Reconnaissance from Pyramid Harbor to Eagle City, Alaska: Twenty-first Ann. Kept. U. S. Geol. 

Survey, pt. 2, 1900, p. 348.
PACIFIC DRAINAGE. 53

seventh meridian, there makes a sharp bend to the southwest and enters the 

mountains in a rock canyon several hundred feet deep. The canyon walls are cut 

off at the top by a bench which has a width of a mile or more, and undoubtedly 

marks a former valley floor. The canyon and bench are said to be continued 

downstream nearly to the head of the delta, the depth of the canyon increasing' 

toward the sea.

The Kaskawulsh River, the west fork of the Alsek, has its source near latitude 

60° 30', in a large irregular-shaped lake called Dezadeash, from which it flows 

northwesterly for about '20 miles; then it bends to the west and finally flows 

almost due south as it enters the mountains in about latitude 60° 20'. Its upper 

valley is broad, but of its lower course little is known. One large tributary, the 

Jarvis River, rises in Aishihik Lake; another, the Oconnor, springs from a glacier 

of the same name, and receives an unnamed tributary, which also has a glacial 

source in the high ranges to the southwest near Mount Hub bard.

The following is quoted from a publication by the writer:

"The Alsek River system" includes a region of extremely varied topography. 

Its upper waters lie within the Yukon plateau, and here the valleys have been cut 

some 3,000 to 4,000 feet below the general level. The basin is drained by valleys 

which cut entirety through the St. Elias Range, and here the relief must be many^ 

thousand feet, but accurate data are entirely lacking. The Alsek is said to be fed 

by numerous glaciers in that part of its course where it cuts the range. Waterfalls 

and rapids have been reported on both the lower Tatshenshini and the Kaskawulsh. 

The elevation of the Dalton House (lat. 60°, long. 137°) is about 2,500 feet, so that the 

Tatshenshini waters fall about that much in the distance of 100 miles to the sea. As 

would be expected from this fact, the reports state that the river is swift and turbulent. The maps show that the Alsek empties into Dry Bay, which reaches almost to 

the base of the mountains. This bay was thus named because its bottom is uncoverd 

at low tide. 1 '

Owing to the turbulent character of the Alsek and its two forks, navigation is 

impossible for any but small boats, and is very difficult even for these. The coast 

natives are said to ascend to the forks only. An additional menace to boats is 

found in the fact that a number of tributary glaciers partly block the river 

channel. The heavy snowfall and absence of fuel other than willow in the lower 

Alsek Valley does not invite winter travel. It can, therefore, be assumed that 

this was never used as a native route of communication between the coast and 

the interior.

During the rush to the Klondike gold fields, even the Alsek route, uninviting 

as it seemed, found its victims, and upward of 300 persons landed in the spring of 

1898 near the head of Disenchantment Bay. Many of these laboriously hauled their 

outfits, including boats, across the Hubbard Glacier, a distance of 50 miles or more, 

to the Alsek River. Here the majority became discouraged, but some persevered 

and continued up the Alsek during the summer months. Winter camps were 

established in a region almost devoid of fuel, and great hardships and privations 

ensued, a number of deaths resulting from freezing and sickness. In the spring of

a Brooks, A. H., Reconnaissance from Pyramid Harbor to Eagle City, Alaska; Twenty-first Ann. Kept. U. S. Geol. 

Survey, pt. 2,1900, p. 349.
54 GEOGRAPHY AND GEOLOGY OP ALASKA.

1899 probably not over a dozen of the original number reached Dalton House, on 

the Tatshenshini River. They had endured eighteen months of hard labor and 

privation, only to find themselves at a point on the Dalton Trail which can be easily 

reached from the coast in a few days' travel.

YAKtTTAT BAY.

Connecting the delta of the Alsek with Yakutat Bay to the west is a series of 

lagoons and channels which offer a water passage for canoes; and tributary to these 

are some small rivers. A railway is now in construction which is to transport 

salmon from these rivers to the cannery at Yakutat Bay, and it will also be used for 

exploiting the heavy growth of timber along its route.

Yakutat Bay itself receives no important drainage channels. Westward to the 

Copper River are miles and miles of glaciers along the coast; some discharge directly 

into the sea, but most of them front a gravel plain which shelves down to the coast. 

The few small rivers found in this belt merit no special description; their courses 

are entirely within the piedmont region, which is heavily forested.

COPPEK BASIX.

A broad, gravel- and silt-floored basin stretches north from the inland slope 

of the Chugach Mountains to the foothills of the Alaska Range. It ifi bounded on 

the east by the Wrangell Mountains and the Copper River, and extends westward 

to the Sushitna basin by a depressed area lying between Talkeet Mountains and the 

Alaska Range. The basin floor has a monotonous lack of relief, which contrasts 

strongly with the rugged mountains encircling it (PI. XIV, B). At the escarpment 

on its eastern margin, where it falls off to the Copper River, it stands about 2,000 

feet above sea level, but it rises gently to the wrest to an altitude of about 3,000 feet 

at the divide. This topographic feature is, in fact, a plateau built up largely of 

Pleistocene deposits, deeply dissected near its margins, and called the "Copper 

River Plateau," by Mendenhall, 0 who was the first to describe it (PI. XXV). 

While it is usually an almost unbroken plain, it is varied in places by hills and small 

groups of mountains, and is dotted with small lakes.

The Copper River Plateau lies entirely within the Pacific Mountain system, 

and though of low relief, includes three important watersheds. Its eastern drainage falls into the Copper, its western into the Sushitna and Matanuska, and a 

small area in the north drains to the Tanana through the Delta River.

The Copper River has its source in the mountains east of the plateau, 

traverses its eastern margin, and, passing through the Chugach Mountains, 

debouches into the Pacific across a broad delta. Along its upper course it is fed 

by many glacial streams from the high mountains lying to the south and east, 

and its westerly tributaries receive a large part of the drainage of the Copper 

River Plateau. The entire basin comprises an area of about 23,000 square miles. 

The following general description by Schrader and Spencer still holds good, 

though the topographic mapping done during 1902 makes it possible to add more 

details:

aMendenhall, W. C., A reconnaissance from Resurrection Bay to the Tanana River, Alaska: Twentieth Ann. Rept. 

U. S. Geol. Surrey, pt. 7,1900, p. 297.
PACIFIC DRAINAGE. 55

"Copper River 3 rises on the northern side of Mount Wrangell and, assuming 

a northward course, which is maintained for about 40 miles, turns toward the 

southwest and continues for 50 miles, when it turns again and bears more to 

the east; then, continuing in this direction, it is joined by Chitina River at a 

distance of about 150 miles from its head. Finally, after having half encircled 

the great Wrangell group of mountains, the river turns toward the south and 

traverses the Chugach Range in a comparatively constricted valley, reaching the 

Pacific Ocean about 150 miles west of St. Elias. It is just below this southerly 

bend that the river is joined by the Chitina, the tributaries of which reach the 

glaciated divides of the Tanana and the White on the east and those of the 

coastal watershed in the region north and west of St. Elias."

The Copper River has its source in a large glacier (Copper Glacier), which 

is fed by the neve fields of the northern slope of Mount Wrangell, and flowing 

northward for some 10 miles through a narrow valley it emerges into a broad 

basin, where its volume is increased by the Batzulnetas River from the east and 

the Slana River from the north. It flows northwesterly as far as the mouth of 

the Slana, beyond which it turns first west and then southwest, and is joined by 

the Chistochina, a river flowing southward through a broad valley from the icecovered slopes of the Alaska Range.

Below the mouth of the Chistochina a broad basin 60 miles in width stretches 

from the Wrangell Mountains on the east to the margin of the Copper River 

Plateau on the west. Both walls of the basin have gentle slopes, broken here 

and there by terraces of silts or gravels, in which the Copper and its tributaries 

have often incised sharp channels. South of latitude 62° the walls of the basin 

approach each other, and finally at the mouth of the Chitina the Copper enters a 

narrow, steep-sided valley, and follows it for 75 miles to the head of the delta.

In the broader part of its valley the Copper receives from the north the 

Gakona and the Gulkana rivers, which rise in glaciers of the Alaska Range. 

The Tazlina, Klutina, and Tonsina are tributary from the northwest, and have 

their sources along the inland slope of the Coast Range. The Wrangell Mountains contribute a number of glacial streams to this part of the Copper, of which 

the Sanford, Klawasi, Nadina, Dadina, Chetaslina, and Cheshnina are the largest.

The Klutina Valley is the route of the military trail from Valdez over the 

Thomson Pass; Copper Center, the most important settlement of the basin, is located 

at the mouth of the river. Chistochina, the second camp of importance, situated at 

the mouth of the river of the same name, is the distributing point for the placer 

fields. Both places are connected with the coast and with Eagle, on the Yukon, by 

the military telegraph line.

The Chitina River joins the Copper from the east, at the lower termination of 

the Copper basin, of which the Chitina Valley is an eastern extension. This stream, 

the largest tributary of the Copper, rises in a glacier on the slopes of the St. Elias 

Range and flows northwestward through a broad valley about 120 miles long. Its 

principal tributary is the Nizina, which springs from a glacier of the Skolai Mountains to the north; numerous other streams join it from both north and south.

«Schrader, F. C., and Spencer, A. C., Geology and mineral resources of the Copper River district, Alaska: U.S. 

Geol. Survey, 1901, p. 29.
56 GEOGRAPHY AND GEOLOGY OF ALASKA.

The lower constricted part of the Copper River Valley, between the mouth of 

the Chitina and the head of the delta, is hi general steep-sided and rockbound, but 

in only one place can it be designated a true canyon. This, called "Wood Canyon," 

is several miles in length and has perpendicular walls. The streams tributary to 

this part of the Copper also flow in narrow valleys with precipitous slopes. The 

most important are the Tiekel and Tasnuna from the west and the Bremner from 

the east.

Schrader and Spencer" give the following description of the delta:

"Eastward from Prince William Sound the mountains of the mainland are 

bordered by a low area of mud flats having a width of 5 to 15 miles. Across the 

eastern portion of this lowland flow Eyak and Sheridan rivers, the latter draining 

the glacier of the same name. Only a short distance from the mouth of Sheridan 

River is the westernmost slough of Copper River, the first of the many distributaries 

of the Copper which come to the ocean at intervals for a distance of over 50 miles 

along the coast. The lower course of the Copper seems once to have been a wide 

embayment reaching back into the Chugach Mountains, but this has been filled in by 

vast quantities of sediments brought down by the river, and the broad delta is the 

result of their deposition."

The Copper River is a mud-laden, turbulent stream throughout its course. 

Above the point where it enters the mountains it is usually spread out into numerous 

channels, with many sand bars and islands. From its source to the sea it falls about 

3,000 feet, 1,000 of which is in the lower 200 miles of its course. The average 

gradient of its entire length is about 12 feet to the mile.

While for the most part unnavigable for steamers, small boats have been used 

extensively on its turbulent waters and on some of its tributaries. The greatest 

danger to boating is encountered in passing Childs and Miles glaciers, which in 

part block the river with their discharge; but these are rapidly receding.

The Copper River natives were accustomed to make annual visits to the coast 

in their moose-skin boats long before white men ever penetrated the interior basin, 

and in the low divides between the headwaters of the Copper River and the Tanana 

they found easy routes for inland excursions which brought them into close relation 

with the Tanana natives.

Tn 1898 the first attempt was made to find a route into the Yukon by the 

Copper River Valley. During the excitement of that year about 3,000 people 

landed at the upper end of Port Valdez with the intention of crossing the 

Chugach Range into the Copper River Valley by a route which led over the 

Valdez Glacier and a high summit (5,000 feet), and thence down a western 

fork of the Copper River. Though the crossing of the glacier and mountains, 

while burdened with provisions and outfit, proved a difficult and dangerous task, 

yet many succeeded, and tons of supplies were thus laboriously taken inland. The 

War Department has since built a horse trail across the Thomson Pass (2,400 

feet) in the Chugach Mountains, which affords an easy route to Copper River and 

to the Yukon, and is used both winter and summer for the United States mail.

o Schrader, F. C., and Spencer, A. C., Geology and mineral resources of the Copper River district, Alaska: U. S. 

Geol. Survey, 1901, p. 27.
PACIFIC DRAINAGE. 57 

COPPER RIVER TO COOK INLET.

The coastal belt between the Copper River and Cook Inlet sends its drainage 

to the Pacific through small streams which fall precipitously from the high 

mountains close to the coast. Many large glaciers discharge into the fiords of 

Prince William Sound and of the eastern shore of Kenai Peninsula. Portage Bay, 

the western arm of Prince William Sound, is connected by a low glacier-filled pass 

with Turnagain Arm. This gap has long been used by the natives. A broad valley 

stretches inland from Resurrection Bay, aad its upper end is separated from streams 

flowing into Turnagain Arm by a pass only 1,000 feet high. Through this natural 

highway into the interior a railway is now being built.

Many of the easterly tributaries of Cook Inlet spring from glacial sources in the 

Kenai Mountains, and these traverse a gently westerly sloping upland to tide water. 

The largest are the Kaknu and the Kasilof rivers. Three large lakes Tustumena, 

Kenai, and Shilak lie along the border of the upland and the mountains, and drain 

into Cook Inlet.

SUSHITNA BASIN.

Between the Kenai Peninsula and the Chugach Mountains on the east and 

the Aleutian and Alaska ranges on the west lies a broad depression; its southern 

half is occupied by the waters of the Pacific, forming Cook Inlet, and its inland 

portion by the valleys of the Sushitna and Matanuska rivers. During countless 

ages these rivers have been building up their delta mouths, gradually encroaching upon tide water, and the valley floors of their lower courses represent the 

silted-up portions of the former extension of the inlet. The broad tidal flats at 

the mouths of both rivers bear witness that this action has not been interrupted.

The Sushitna River system drains an area of about 8,000 square miles lying 

east and south of the Alaska Range. Its western tributaries rise in the glaciers 

of that range, while its eastern ones reach far out into the Copper River Plateau. 

The main Sushitna issues from a glacier of the Alaska Range and flows southeast 

through a narrow valley until it emerges from the mountains upon the plateau, 

then bends almost due west. This course continues for about 60 miles; for the 

first 30 in a broad valley, and then through a rock canyon, where the river makes 

a sharp southerly turn in latitude 63°. Here the valley begins to broaden 

gradually until it finally merges with the broad basin of Cook Inlet.

On the west the Sushitna is joined by the Chulitna, Peska or Croto, and Yentna, 

which with their chief tributaries all head in glaciers of the Alaska Range. The 

mountain portions of streams lie in typical glaciated valleys, with U-shaped cross 

sections. As they emerge from the mountains their slopes are bounded by high 

terraces, but these gradually disappear, the walls grow farther apart, and the 

bottoms finally merge with the Sushitna lowlands. The Tokichitna joins the 

Chulitna from the west in about latitude 62° 30'. In about latitude 63° a the 

Chulitna receives from a glacier an unnamed tributary which occupies the 

northerly extension of the main Chulitna Valley. Fifty miles above is a broad 

gap called Caribou Pass, 2,500 feet in altitude, which separates the Cook Inlet 

drainage from north-flowing waters.

aEldridge, G. H., See map accompanying Reconnaissance in the Sushitna basin and adjacent territory, Alaska: 

Twentieth Ann. Kept. TJ. S. Geol. Survey, pt. 7, 1900, pp. 1-29.
58 GEOGRAPHY AND GEOLOGY OF ALASKA.

The Talkeet is the only large eastern tributary of the Sushitna. Along the 

headwaters of this stream the western extension of the Copper River Plateau 

enters the Sushitna basin, and the Talkeet for almost its entire length is incised 

in the plateau. Its lower course lies through a rock canyon.

The Sushitna is a turbulent, silt-bearing stream, which flows in many channels; and the same is true of most of its tributaries. It is not easily ascended 

even in small boats, though this has been accomplished many times. A steamboat 

has been taken up the Sushitna as far as the mouth of the Chulitna, and up the 

Yentna to the mouth of the Keechatna."

The entire Sushitna basin has long been a hunting ground for the natives of 

Cook Inlet and the Sushitna Valley, and Caribou Pass afforded them means of 

communication with the Tanana Indians, but it does not seem to have been much 

used. This is undoubtedly one of the easiest routes through the mountains which 

separate the Yukon basin from the Pacific coastal province, and is suitable for a 

railway. Several passes, but of greater altitude, are found near the sources of 

some of the southern tributaries of the Yentna. These, though they permitted 

intercourse between the Kuskokwim and Sushitna natives, were nevertheless almost 

ignored before the coming of the white, man,

MATANUSKA BASIN.

Of the rivers flowing into Cook Inlet the Matanuska, 6 emptying into Knik 

Arm a long, narrow tidal waterway connected with the northern part of the 

inlet is second in size only to the Sushitna. It flows southwesterly from a source 

north of the Chugach Mountains, near the southwestern margin of the Copper 

River Plateau, its valley separating the Talkeet Mountains on the north from the 

coastal mountains to the south. Much of its course is through a canyon incised 

in an older valley floor, the remnants of which are preserved as gravel-covered 

benches (PI. XV, A). Its most important tributary is Knik River, which joins 

it from the east.

The upper end of Cook Inlet receives from the west a number of small rivers, 

which have their sources on the eastern flank of the Alaska Range, and are 

mostly glacial streams. To the south the Aleutian Range rises almost directly 

from the sea, and drains to the Pacific entirety through small streams. As the 

divide is close to the eastern shore throughout the Alaska Peninsula, there are 

no drainage ways on the eastern side worthy of mention. The topography of the 

Aleutian Islands, as far as known, is rugged, and none of them are large enough 

to feed anything but small streams.

SUMMARY.

The Pacific drainage of Alaska is carried to the sea by six important rivers, 

and many minor streams. Three rivers the Stikine, Taku, and Alsek have 

their sources in the Interior Plateau region, and break through the coastal mountain belt to reach tide water. The valley of another, the Chilkat, separates two 

of the coastal ranges. The Copper River also traverses one range of coastal

a Brooks, A. H., -Exploration in Mount McKinley region: Prof. Paper U. S. Geol. Survey. (In preparation.) 

b Mendenhall, W. C., Reconnaissance from Resurrection Bay to the Tanana: Twenty-first Ann. Rept. TJ. s. Geol. 

Survey, pt. 7. 1900, p. 299.
U. 8. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 45 PL. XV

A. VIEW UP MATANUSKA VALLEY FROM GLACIER POINT. 

Showing recent gorge in older valley.

B. YUKON VALLEY AT DAWSON,
BERING SKA DRAINAGE. 59

mountains, but as the Pacific Mountain system broadens out to the northwest 

and includes several ranges, its headwaters do not reach inland to the plateau 

province; its drainage basin includes a large part of the so-called Copper River 

Plateau, which is hemmed in on three sides by high mountain ranges. The 

Sushitna, the sixth of the important rivers, has its basin eritireh' within the 

Pacific Mountain system. Its lower valley is an inland extension of the Cook 

Inlet depression, and it receives the eastern drainage of the Alaska Range and a 

part of that of the Copper River Plateau.

Much of the Pacific drainage is from a region of abundant precipitation, 

and in volume of water the streams are out of proportion to the areas which 

they drain. In the highlands much of the precipitation is snow, which rinds its 

way to the lowlands in the form of glaciers.

BERING SEA DRAINAGE. 

OUTLINE.

Bering Sea drains nearly all of the vast Central Plateau region and much 

of the inland slopes of its bordering ranges, an area comprising not only over 

half of Alaska but also a considerable part of British Northwest Territory and 

British Columbia. For purposes of discussion it is convenient to consider this 

drainage in its four natural subdivisions, named from south to north as follows: 

Bristol Bay, Kuskokwim River, Yukon River, and Norton Sound. The rivers 

and streams flowing into Bristol Bay, a deep indentation of the shore line north 

of the Alaska Peninsula, comprise the southernmost of these divisions. The 

Kuskokwim basin lies adjacent on the northwest, and is in turn bounded also on 

the northwest by the great Yukon basin. The fourth province embraces the 

many small rivers which flow into Norton Sound.

BRISTOL BAY.

The largest volume of water contributed to Bristol Bay comes through the 

Kvichak, which joins the bay at its extreme northern end and drains an area 

blocked out by the northern end of the Aleutian Range on the east, the Alaska 

Range on the north, and the Kuskokwim divide on the north and west. This 

basin includes also the two largest lakes of Alaska, Iliamna and Clark. The 

Kviohak heads in the former and flows southwest across a lowland for about 50 

miles, into a tidal estuary at the head of Bristol Bay. The fall from the lake 

to the sea does not exceed 50 feet, and the Kvichak is reported to be very 

shallow and its current not swift. Large rowboats ascend to its source without 

serious difficulty.

Iliamna Lake, a broad sheet of water, lies between the fifty-ninth and sixtieth 

parallels of latitude; its most easterly point is said to be only 12 miles distant 

from tide water at Cook Inlet. No surveys have been made of the lake, but 

according to report it is about 50 miles long and 15 or 20 wide, with an elevation 

of less than 50 feet above tide. The lower shores are bordered by a broad 

lowland which stretches southwest beyond the valley of Nushagak River to 

Bering Sea and southward along the western shore of the Alaska Peninsula. On
60 GEOGRAPHY AND GEOLOGY OF ALASKA.

the south and east the Aleutian Range constitutes a barrier between Iliamna 

Lake and Cook Inlet. At its lower end it measures 50 miles or more in width 

and 3,000 to 4,000 feet in altitude; but to the north both width and altitude 

decrease until a single ridge 2,000 or 3,000 feet in height is all that intervenes 

between the lake and tide water. The east shore of the lake is said to be 

formed by a gravel-floored plain sloping up to the abrupt face of the mountains. 

A pass at a height of about 800 feet affords an easy route of communication 

between the upper end of Iliamna Lake and a bay of the same name on Cook 

Inlet, and has long been in use 'by whites as well as natives.

The tributary drainage is unmapped, but the Nogheling, which drains Lake 

Clark at the north, and is not over 30 miles in length, is probably the largest 

river. The difference in altitude between the two lakes has been estimated at 

from 50 to 100 feet, for the Nogheling is known to have a very steep gradient, 

with many rapids and probably falls.

Lake Clark," also unsurveyed, is reported to be 55 miles long and about 10 

miles wide at its lower end, narrowing to 2 miles at its upper end. Its 

geographic position is undetermined, but the eastern shore is probably at least 

25 miles west of Cook Inlet possibly 50. The Chulitna River, which enters the 

lake from the north, is said to have its source in the mountains lying 30 or 40 

miles west of the upper part of Cook Inlet. The eastern tributaries of the lake 

are short, as they rise in the Aleutian Range which skirts the eastern shore. 

Several of the most northerly emerge from small glaciers. The western tributaries are longer and several are known to rise in small lakes, but beyond this 

little is known about them. The Chulitna, possibly the largest, flows through a 

lowland region, and near its headwaters a short portage connects it with waters 

flowing into Nushagak River, also tributary to Bristol Bay.

Around the upper end of Lake Clark the mountains are said to be bold, 

with altitudes of 5,000 to 6,00<i feet; but they decrease in height to the south, 

and near the southern end of the lake fall to a rolling upland of low relief. 

The actual shores of the lake are said to have gentle slopes, and terraces are 

reported on its east side near the southern end.

A deep estuary forming the northwest arm of Bristol Bay receives the waters 

of the Nushagak River, which far exceeds the Kvichak in length, though not in 

volume. One hundred miles from tide water the river divides; The west fork 

rises in Tikchik Lake, said to be about 20 miles long and to be linked on the north 

with a series of smaller lakes, affording an almost continuous water route to the 

middle Kuskokwim; and the east fork, called the Mulchatna, has its source near the 

head of the Chulitna, which empties into Lake Clark, and is connected with the 

Nushagak by the short portage already referred to. Wood River rises in a lake 

about 20 miles from the coast and flows southward into the same estuary as the 

Nushagak.

A number of small rivers which drain small lakes are tributary to Bristol 

Bay through southerly courses. The largest of these, the Togiak,* has its source

a The writer is indebted to Mr. Wilfred H. Osgood, of the Biological Survey, for sketch map and notes on this region 

in advance of the publication of his report, Mr. M. W. Gorman, who collected in the Lake Clark region for the Department of Agriculture, also kindly furnished valued information.

bSpurr. J. E., A reconnaissance in southwestern Alaska: Twentieth Ann. Kept. U. S. Geol. Survey, pt. 7, 1900, p. 87.
BERING SEA DRAINAGE. 61

in a lake of the same name, about 50 miles from the coast. Togiak Lake is 

about 15 miles in length and lies in a broad valley, which opens toward the south 

and merges with the lowland belt bordering Bering Sea. The natives have a 

portage route from the head of a stream entering the west side of the lake to 

the head of Kanektok River, which flows westward into the Kuskokwim estuary.

A large part of the Alaska Peninsula drains into Bering Sea through streams 

flowing from lakes within the mountain bolt of its eastern half. After leaving 

the mountains these streams traverse with sluggish currents the lowland belt 

which skirts the western shore of the peninsula, and as the lowlands gradually 

narrow to the south the streams become correspondingly shorter. None of these 

water courses have been accurately mapped, and few are of sufficient size to merit 

special description.

The affluents to Bristol Bay are, as a rule, short and drain lakes which are 

not far above sea level. Iliamna and Clark, the largest of these lakes, receive 

the waters of a large area, including the southern end of the Alaska Range and 

the western slope of part of the Aleutian Range. The topography is of two 

essentially different types: First, the coastal lowlands, over which the drainage 

channels meander sluggishly; and secondly, the mountain region, where the drainage system is better defined. The lakes so abundant in the region lie, for the 

most part, at or close to the line of demarcation between these two topographic 

provinces.

KTJSKOKWIM BASIN.

The area roughly blocked out by the Alaska and Aleutian ranges, the Tanana 

and Yukon rivers, and Bering Sea has been explored only in part. Its topography, 

as far as known, consists of rounded hills and low mountains, seldom exceeding 

2,000 feet in altitude, interpenetrated by broad river valleys and many lowlands. 

As has been indicated, the waters of the eastern part of this area, including Lakes 

Iliamna and Clark, find outlet into Bristol Bay through several small rivers; but 

the greater part of the drainage is carried to Bering Sea by the Kuskokwim River, 

the second in size of Alaska, possessing a catchment basin of probably more than 

50,000 square miles.

Manv headwater streams of the Kuskokwim rise in glaciers on the inland slope 

of the Alaska Range and flow northwester!y, their channels gradually uniting into 

four or five rivers which are tributary to the two trunk streams, whose junction 

in latitude 63° can be regarded as the beginning of the Kuskokwim proper. 

Geographic usage has applied the name Kuskokwim to the southern fork, while 

the other, whose valley trends northeast and southwest, is called the East Fork of 

Kuskokwim. Mr. Spurr informed the writer that there is very little difference in 

the volume of the two rivers at their junction, but the southern, or Kuskokwim 

proper, is somewhat larger. According to this nomenclature the Kuskokwim 

River rises in the unexplored mountain mass at the southern extension of the Alaska 

Range, and its headwaters probably interlock with streams tributary to Lake Clark.

The Spun1 " party, which explored the Kuskokwim River, reached it on their 

way through the Alaska Range in latitude 62°. Between that point and its source

<*Spurr, J. E., Reconnaissance in southwestern Alaska: Twentieth Ann. Kept. I'. S. Geol. Survey, pt. 7, 1900, pp. 51 

and 52. See pp. 128 et seq., this report.

17211 No. 45 06 5
62 GEOGRAPHY AND GEOLOGY OF ALASKA.

the river is unsurveyed, but it is known to extend due south for 20 miles through a 

broad valley with slopes that rise gradually to mountains 5,000 and 6,000 feet in 

altitude (PI. XI). In about latitude 62° the river makes a right-angled bend to 

the west and breaks through a minor range in a rock canyon about 5 miles in length. 

A broad valley" above this canyon is continued to the south as a depression, from 

which a pass leads into the valley of the Pleasant River, belonging to the drainage 

system of the Sushitna on the east side of the range. Beyond the mountains the 

Kuskokwim flows for 40 or 50 miles through another wide valley running north and 

south, the upper part of which is occupied by the Hartman River. The valley 

slopes are steep, broken only here and there by irregular glacial terraces, while the 

mountains on either hand rise to altitudes of 6,000 and 7,000 feet. In this interval 

the Kuskokwim receives two important tributaries, the Rohn River from the east 

and Post River from the southwest. The valley of the former is glaciated and 

reaches well back into the Alaska Range to a glacial source. Post River * occupies 

a broad, flat valley verging to the southwest, and its upper course is bounded on the 

west by snow-covered mountains, from which small glaciers discharge into the Post 

River or its tributaries.

From the point where it leaves the mountains in latitude 62° 30', to its junction with the East Fork, the Kuskokwim flows northwesterly across the upper 

Kuskokwim Flat. This has already been described as a broad lowland area, to 

which the Alaska Range falls off abruptly (PI. XI). At the base of the mountains 

the lowland has an altitude of about 4,000 feet, and slopes gradually to the northwest. As will be shown elsewhere, this was a region of slight relief which has 

been deeply buried in overwash, glacial gravels, and silts during the retreat of the 

ice sheet; and into these loose deposits the Kuskokwim has incised its channel to a 

depth of a hundred feet or more, sometimes carving out bold bluffs by undercutting.

Between the mountain front and the fork the Kuskokwim receives three tributaries from the east, the Jones, Dillinger, and Tonzona rivers, of which the two 

latter are the largest and have glacial sources. All of these emerge from the mountains in U-shaped valleys, and cross the plain through canyons incised in the gravels 

to a depth of a hundred feet or more.

The current of the upper Kuskokwim is swift, and above the mouth of the 

Hartman River is hardly navigable even for canoes. Below this point it broadens 

out into many channels, broken by islands and sand bars, and obstructed by snags 

and driftwood. According to a rough estimate by the writer, the current is 5 to 6 

miles an hour at the mouth of the Rohn River, but as the river approaches its 

junction with the East Fork its course becomes more tortuous and its current 

more sluggish.

The East Fork of the Kuskokwim rises in about latitude 64° 30', where its 

drainage courses dovetail with streams flowing northward into the Tanana. An 

easy portage route, long used by the natives, leads from these headwaters to the 

Cosna River, tributary to the Tanana. In latitude 64° another portage trail, 

about 15 miles in length, is used by the natives in passing from the East Fork

aSpnrr, J, PL, Reconnaissance in southwestern Alaska: Twentieth Ann. Kept. U. S. Geol. Survey, pt. 7, 1900, map No. 

6, p. 102,

''This river was omitted from Spurr's map. See map accompanying report entitled, An exploration in the Mount 

McKinley region, Alaska, (In preparation.)
BKRING SEA DRAINAGE. 63

to Lake Minchumina, which is drained by the Kantishna, a tributary of the 

lower Tanana. The broad valley of the East Fork trends southwest between low 

hills." Most of its waters come from the east, for on the west the watershed 

which divides its drainage from that of the Yukon lies close to the valley's edge.

Its chief easterly tributaries, the Chedotlothna and Tatlathna, meander for 

the lower 20 miles of their courses through broad fiat valleys, and above to the 

base of the mountains they arc incised to a depth of 100 feet or more in the 

gravel plateau. Near the mountains the rivers break up into many minor 

streams, the majority of which tind their sources in glaciers. Some of these 

glaciers reach to the lowland and discharge into the streams near the foot of the 

range; but where they have retreated the water courses penetrate to their fronts 

in U-shaped valleys.

Herron 6 Glacier, one of the largest, is fed by the snow fields of Mount Foraker 

and continues to the front of the range, where it discharges into Herron River, 

a southern fork of the Tatlathna.

Below the junction the Kuskokwim continues its northwesterly course for 30 

miles, and here receives one important tributary from the west, the Tachat River. 

This stream is unmapped, but is reported to have its source near an eastern tributary of the Innoko, which flows into the Yukon, and to be connected with it by 

a short portage.

Near the one hundred and tifty-fifth meridian, where the Kuskokwim encounters a series of low hills, it makes a right-angled bend to the south, and a few 

miles farther on low hills appear on its eastern side also, the flats are left behind, 

and for nearly 100 miles the valley is well defined, bounded by hills whose summits 

seldom exceed 1,000 feet. Then in latitude (>2° the east wall of the valley recedes, 

giving place to broad lowland; and the river receives the Chagavenapuk, an unexplored easterly tributary. The main river now flows southwest for 50 miles, 

closely hugging the low hills, which still continue on the northwest. A right-angled 

bend to the northwest then brings it into the so-called Kuskokwim Mountains, 

and it is joined by the Holiknuk, a river said to rise far to the south, in headwaters which interlock with those of the Nushagak and streams flowing- into Lake 

Clark. For a distance of about 200 miles, in which it receives several small tributaries, the Kuskokwim flows through the Kuskokwim Mountains in a broad, flat 

valley, characterized by large rectangular bends; then in about latitude 61° 30' it 

enters the flat tundra belt of the coastal region. Spurr'' has noted that this junction between the mountains and the tundra is abrupt. Near the southern limit 

of the mountains, the Kuskokwim and Yukon are separated by only 15 miles of 

flat tundra, and a series of lakes and streams afford an easy portage for small boats.

As it meanders sluggishly through many tortuous channels across the coastal 

lowland, the Kuskokwim receives one important tributary from the east, the 

Kwikli. The small delta of the Kuskokwim, embraced within a belt probably 20 

to 30 miles wide, is in strong contrast with that of the Yukon, which occupies 

more than 100 miles of the coast of Bering Sea. Several small rivers flow into

i Herron, J. S., Explorations ill Alaska in 1899; Adjutant-General's office, No. 31.

!> Named by the writer after Capt. Joseph S. Herron.

< Reconnaissance in southwestern Alaska: Twentieth Ann. Rept. U. S. Geol. Survey, pt. 7, 1900, p. 69.
64 GEOGBAPHY AND GEOLOGY OF ALASKA.

Kuskokwim Bay, of which the Kanektok, the largest from the east, rises within 

the Ahklun Mountains, 50 miles beyond the foot of the range.

This second largest river of Alaska drains a large area lying west of the Alaska 

and Aleutian ranges, and south and east of the lower Yukon, Its headwater tributaries, of which the most important have their sources in glaciers from the western 

slopes of the Alaska Range, flow westward across a lowland area and unite in two 

main trunk streams, which in turn unite to form the Kuskokwim proper. The Kuskokwim Valley for about 400 miles below the forks is broad, widening out to a 

lowland. Farther downstream the river leaves the upland region and continues to 

the sea across the coastal tundra belt. Its mouth is characterized by the absence of 

any considerable delta.

The Kuskokwim is navigable for steamers up to the forks, 500 miles from the 

mouth, and the ascent was first made in the summer of 1901. The southern fork, or 

Kuskokwim proper, can probably be ascended for 20 miles or more by steamer, and 

the East Fork a somewhat greater distance, while small boats cau push still farther. 

Attention has already been called to the portages which connect some of the tributaries of the Kuskokwim with those of the Yukon basin. Though Kuskokwim 

River is easily navigable, before the coming of the white man the natives of the 

upper river seem to have had little communication with those near the coast. Their 

intercourse was rather with the natives of the Tanana and Yukon.

Russian traders had established themselves on the Kuskokwim 300 or 400 miles 

from the mouth before the middle of the nineteenth centurj-, but after the transfer 

of the territoiy this post was abandoned, and the natives of the upper river long 

depended for their supplies on the lower Yukon trading posts, where they took 

their furs for barter. Since the establishment in 1901 of a trading post near the 

great forks of the river, 500 miles from the sea, the natives have avoided the long 

journey to the Yukon.

YUKON BASIN. 

OENERAI, DESCRIPTION.

The Yukon is the largest stream, of Alaska, the main artery of an extensive 

drainage system which gives easy access to much of the vast intermontane region. 

To the natives the river is and has been all important, for through countless generations its waters have furnished them fish for food and easy routes of travel bv canoe 

and raft in summer and sled and dog-team in winter. The white men, too, found 

access to the interior by this river. The Russians, coming from the west in search 

of furs, dragged their clumsy boats for a thousand miles against its current; while 

the English traders, who reached its headwaters from the east, descended in their 

bark canoes for hundreds of miles. One of the headwater tributaries rises in the 

Chilkoot Pass not two score miles from tide water on the Pacific, and furnished an 

inland route to the coast natives and later to the prospectors who discovered the Yukon 

gold fields. Now the railway through the Coast Range makes the upper Yukon 

basin still more accessible. Scores of steamers navigate the Yukon during the 

summer months, and its frozen surface affords a highway for winter travel. In 

short, the settlement by natives and whites .and the development of all the mining
YUKON BASIN. 65

interest of the great interior region of Alaska and northwestern Canada were only 

made possible by the Yukon waterways.

The Yukon, with its longest tributaries, the Lewes and Teslin, has a length 

of about y,300 miles and a catchment area of about 880,000 square miles, over 

half of which is in Canada. The following table shows it to be fifth in rank 

among the rivers of North America:

Mississippi, \vith Missouri.. 

Winnipeg and Nelson..........

Mackenzie ....................

@t. Lawrence..................

Yukon, with Lewow and Teslin.

Length.

0,000 

:!, 840 

2, 86S 

2, 600 

2, 300

1,244,000

486, 500

677, 400

565, 000

330, 000

The Yukon is comparable in length to the St. Lawrence/' but drains a much 

smaller area. The discharge of the Yukon has l)een approximately gaged by 

Dawson^' at the confluence of the l^elly and Lewes, or the head of the Yukon 

proper. This, based on approximate current measurements made late in the 

summer, when the river is about at mean height, showed a discharge of 66,955 

cubic feet per second.

Ogilvic, who made a more careful measurement of the Yukon at the 

international boundary, makes the following statement:

" At the boundary the river is somewhat contracted and measures only 1,380 

feet across in the winter, but in summer, at ordinary water level, it would be 

about 100 feet wider. Immediately below the boundary it expands to its usual 

width, which is about 2,000 feet. The cross-sectional area at the Ixjundary, measured in December, 1895, is 21,818 feet. There is a channel 600 feet wide, not less 

than 22 feet docp, and one 400 feet wide not less than 26 feet deep. During 

summer level those depths would be not less than 4 feet deeper, and the crosssectional area 27,000. The discharge at this first level is approximately 96,000 cubic 

feet per second; at summer level it approximates 185,000 cubic feet; at flood level it 

approaches 1X0,000 cubic feet or more, possibly reaching for short times 225,000.''"

The following extract, kindly furnished the writer by the Superintendent of the 

Coast and Geodetic Survey, is from the report of Asst. Gr. B. Putnam, of April 

80, 1900:

"To obtain an approximation to the discharge of the Yukon, a cross section and 

current observations were obtained opposite Azacharak Hill (78 miles from the 

mouth), where the river is well confined between banks and carries all the watei

»It should be noted that the St. Lawrence drainage baaln Includes the Great lakes, an area, nf about 90,000 square 

miles.

kDawson, O. 31., Yukon district and Brltlwh Columbia: Ann. Kept. Geol. Nat. Hint. Survey Canada, vul. 8. fit. 1.1889, 

p. 1KB.

 OgllTle, \Vm., The Klondike Ofncial Onlde, BnKalo, 1H98, p. 36.
66 GEOGRAPHY AND GEOLOGY OF ALASKA.

except what little may escape through Kashunuk slough. A drawing of this cross 

section is attached. The area was 160,000 square feet and the surface currents 

varied from 2.20 to 0.98 knots per hour. On the assumption that the current 

throughout each division of the section was the same as that on the surface, the discharge of the river was computed to be 436,000 cubic feet per second on September 

8, 1899.

"This was at low summer stage, about 12 feet below the flood high-water line, 

as indicated by the gravel beach on tho north shore and the de'bris on the inundated 

banks on the south shore. It is believed, however, that the river discharge is much 

less during the winter months, so that the above may not be far from the average 

for the year. It is about two-thirds that of the Mississippi. A comparison of cross 

sections of the Kwikluak and Kwikpak passes just below the separation indicates 

that the former carries over 75 per cent of tho water of the river. The branch of 

the latter that is used by the steamers, the Apoon, carries apparently less than 1 percent of the total discharge of the Yukon; the Kawanak, about 14 per cent, and the 

Okwega, about 3 per cent.

"Tidal observations were made at five points above the mouth; at the last station, 62 miles (statute) from the Kwikluak's mouth, the mean range was 0.4 foot 

per day."

The St. Lawrence has a discharge of about 900,000 cubic feet per second, or 

more than double that of the Yukon. This is what would be expected, for the 

St. Lawrence not only drains a much larger area (the ratio is about 5 to 3), but 

its basin receives much greater precipitation than that of the Yukon.

The sources of the Yukon lie in British Columbia. All of its upper drainage 

channels trend north and northwest until it reaches the Arctic Cii'de, where it 

makes a right-angled bend to the southwest, and continues in this general course 

until it empties into Bering Sea. From latitude 60° to about latitude 65°, where 

it enters Alaska, it flows through the Yukon Territory, and less than half of its 

basin lies in Alaska.

The Yukon basin, comprising an irregular area in Alaska and adjacent portions 

of Yukon Territory and British Columbia, is roughlv outlined on the north, east, 

and northeast by the Rocky Mountain system, and on the south by the Pacific 

Mountain system. There are no considerable highlands on the southeast, for there 

the tributaries of the Yukon, Liard, and Stikine interlock irregularly within the 

plateau region. The chief tributaries of the Yukon are the Koyukuk, Tanana, 

Porcupine, White, Pelly, and Lewes. The main stream begins with the junction 

of the Pelly and Lewes, which sire entirely within Canadian territory.

LEWES JUVKR.

The source of the Lewes is in a small lake on the northern flank of the Coast 

Range only 25 miles inland from the head of Lynn Canal, a tidal estuary of the 

Pacific. In its upper course the Lewes flows through a chain of lakes which are 

connected by narrow, turbulent stretches of the river. The larger lakes from south 

to north are Bennett, Tagish, Marsh, and Lebarge. Tagish is very irregular in 

outline, probably because it is a flooded vallej" system. Here, as well as at Lake 

Bennett, the land often slopes abruptly from the water level, but the other lakes
YUKON BASIN. 67

usually occupy only a part of the wide valley floor. Below Lake Tagish the valley 

is 1 to 5 miles wide, and though the slopes are usually gentle, the actual river 

banks are often silt aud gravel bluffs, rising 50 to 100 feet above the water, and 

forming a terrace whose flat top extends to the valley wall proper (PI. XXV, 7?). 

White Horse Rapids aud Miles Canyon are formed by a mass of recently extruded 

igneous rock, incised to a depth uf 100 feet by the river (PI. XXVI, .A and Z?). 

Five Finger Rapids are also due to a partially dissected rock barrier which has been 

uncovered by erosion, owing to a shifting of the channel.

Near its source the valley of Lewes is incised, to a depth of about 3,000 feet 

below the general level of the plateau (5,000 feet), and as the plateau slopes to the 

northwest with about the same grade of the river the relief does not change 

appreciably.

A broad depression marking an abandoned valley stretches northwest from the 

lower end of l^ake Bennett to a few miles above White Horse Rapids. This flat 

gap, 2 to 10 miles in width, floored with silt deposits, affords a natural route of 

communication which has been followed by the Yukon and White Pass Railway 

connecting Skagway, Alaska, with White Horse, Yukon Territory.

The Lewes has many tributaries, which will only be mentioned in passing. 

The Takhini River, confluent from the west, in latitude 61\ rises near the sources 

of the Chilkat and Alsek rivers. The Teslin," the largest tributary and longer than 

the Lewes above the junction, flows northwest through a remarkably straight valley 

2 to 10 miles in width, which is incised in the plateau.* The upper end of the valley 

is occupied by Teslin Lake, about 75 miles long, in which the Teslin finds its source.

Near latitude 62° the swiftly flowing Big Salmon River joins the I^ewes from 

the southeast. This stream forks about 40 miles above its mouth. Its valley, 

incised in the plateau to a depth of 2,000 to 2,500 feet/' is bounded on the east by a 

high mountain mass, which towers far above the plateau level and forms the divide 

between the Lewes and Pelly waters. Fifty miles below, the Little Salmon, a small 

river, is confluent to the Lewes from the north.

Lewes River descends about 500 feet between its head at Lake Bennett and its 

junction with the Pelly, a distance of about 400 miles, but the gradient is very 

irregular. The velocity of the current varies greatly, according to the stage of the 

water, but at medium high water is probably between 8 and 4 miles per hour. 

Above the mouth of the Teslin the Lewes is most commonly confined to one 

channel, while in its lower portion it becomes more tortuons, and islands and 

sloughs are frequent.

There are no serious difficulties to steamboat navigation on the Lewes up as far 

as the White Horse Rapids, though at low stages the upper end of l^ake Lebarge 

is very shallow. The White Horse Rapids and Miles Canyon are impassable to 

up-bound steamers, but obstruct only a few miles of the river, for above them are 

100 miles of navigable waters as far as Lake Bennett. The now well-established 

route of travel to the Klondike is by railway from the coast to White Horse and 

thence by steamer to Dawson. The downstream journey occupies two to three 

days and the return four to six. The Chilkoot Pass route to Yukon waters was long

"The native name of this river is Teslin, but it Is generally known as the Bootalinqua.

h Bayou, C. AY., An expedition through the Yukon district: Nat. GeoR. Mug., vol. 4, 1892. p. 182.

rMcConnell, R. Q., Salmon River gold nelda: Summary Heport Geol. Survey Canada, 1901, pp. 23 and 24.
68 GEOGBAPHY AND GEOLOGY OF ALASKA.

jealouslj? guarded from the white man by the Chilkat Indians of the coast, who 

desired to continue their monopoly of the interior fur trade. The first prospectors 

crossed the Chilkoot in 1880, and within a few years it became the chosen gateway 

to the Yukon gold fields, so that when the wild rush to the Klondike took place 

probably over three-quarters of the gold seekers selected the Lewes River route. 

The Coast Range barrier once surmounted by crossing the pass, an all-water route 

to the Klondike for small boats lay open, for it is possible for a skilled pilot to run 

the White Horse Rapids with comparative safety.

PELLY BASIX.

Pelly River "has its source in two small lakes which lie in latitude 61°, not 

far from the headwaters of the Liard. Hence it flows northwesterly through a 

broad vallej' characterized by an abundance of sand and gravel terraces. Bold 

bluffs of uncoiisolidated material, which end above in broad terraces which stretch 

to the true valley^ walls, usually confine the river to narrow channels. These 

features indicate that the sharp trenching of the river in the old valley floor is of 

comparatively recent date. During this downcutting some rock barriers have 

been exposed, in which steep-walled canyons have been incised.

The ~Pel\y receives many tributaries from the north and south, of which the 

Macrnillan, confluent from the north about 50 miles from the Yukon, is the largest. 

This stream rises on the western slopes of the front ranges of the Rockies and flows 

almost due west. McConnell* describes the topographj- adjacent to it as follows:

*' The general character of the country in the vicinity of the Macmillan is mountainous, although the ranges, as a rule, are isolated by wide valleys and depressions. 

Below Kalzas River the Macmillan is bordered on the north by the Macmillan Mountains a long ridge with fairly even slopes except near the center, where it rises 

about 1,000 feet above the tree line and is broken into a number of rocky peaks, the 

highest of which has an elevation of about 3,800 feet above the level of the river, or 

5,600 feet above the sea. Opposite the Macmillan Mountains the country bet ween-the 

Macmillan and the Pelly is occupied by a high plateau-like mass with smooth outlines, 

the summit of which rises just above tree line to an elevation of about 2,700 feet 

above the valley. East of this plateau is a wide depression, extending east to Dromedary Mountain and south to the Pelly. This depression is faced on the north of the 

Macmillan by Kalzas Mountain and the range connected with it. Kalzas Mountain 

rises 4.300 feet above the valley and is the highest peak along the main Macmillan 

River. Northeast from it, at a distance of 10 miles, is Clark Peak, a conspicuous 

conical mountain, visible from almost every elevation climbed to along the river.

"The region north of the Macmillan, between the valley of Moose River and 

Russell Creek, is occupied by a high broken plateau, deeply trenched by numerous 

streams flowing into the surrounding valleys. South of the Macmillaii the country 

bordering- on the valley, with the exception of a couple of relatively unimportant 

depressions, is rough and mountainous from Dromedary Mountain east to the Forks. 

The mountains, mountain groups, and broken uplands along the Macmillan Valley

aDawson, G. M., The^ukon district and British Columbia: Aim. Kept. Geol. Nat. Hist. Survey Canada, new series, 

vol 3, 1889, p. 119B.

t> MeConnell, R. G., The Maemillan River, Yukon district: Summary Rept. Geol. Survey Canada for 1902, p. 23.
YUKON BASIN. 69

have a common origin and may be briefly described as representing- surviving- fragments of an extensive highland, the major portion of which has been destroyed by 

subaerial denudation and erosion."

An abandoned drainage channel is described by McConnell," which runs northwesterly, crossing the lower Macmillan diagonally, and intersects the Klondike River 

near its mouth. Its southeastern extension forms a part of the Pelly Valley.

The gradient of the Pelly has not been measured, but is known to be considerably steeper than that of the Lewes, for in the lower 300 miles of its course 

it descends probably 1,000 feet, but is said to be navigable* to steamers for 250 miles.

The Hudson Bay traders explored the Pelly, approaching it from the Liard 

divide, as early as 1840, and established a trading post at Pelly Banks. This route 

to the Yukon via Liard proved so difficult and dangerous that the post was abandoned a few years later.

SUBDIVISIONS OF THE YUKON VALLEY.

The Yukon from its source, at the junction of the Lewes and Pelly rivers, 

flows to Bering Sea through a valley probably 1,500 miles'1 in length, and receives 

many tributaries. Four subprovinces, each of which has certain characteristic 

topographic features, are recognizable in the Yukon and can be conveniently 

used as a basis of description. In the account of these different parts will be 

included the tributary valleys. The valley above the flats, about 450 miles long, 

will be called the "upper Yukon." A second subdivision, termed the "Yukon 

Flats," embraces the great lowland of the central Yukon Valley already described. 

Below this is the "Rampart region," a third subdivision, a constricted part of 

the valley, which extends to the mouth of the Tanana. The rest of the Yukon 

Valley, which is broad and finally widens out to the delta, is the fourth subdivision, called the "lower Yukon."

THE UPPKK YUKON AND TUIBUTAKIKS.

The valley of the upper Yukon is I to 3 miles in width and is bounded by 

walls which rise to the level of the plateau, 1,500 to 8.000 feet above the water 

(Pis. XV, J3. and XVI, />'). Its general north westerly trend is modified by a 

series of large bends which are very suggestive of incised meanders inherited 

from an older drainage system. Along this stretch the river varies in width 

from a quarter to half a mile, usually has but one channel, broken by an occasional island, and has a velocity of 3 to 5 miles an hour.

SEJ.WYN RIVER.

The Selwyn River, the first considerable tributary to the upper Yukon, joins 

it from the south, about 40 miles below the junction of the Pelly and the Lewes. 

It is said to fork about 5 miles up above its mouth.

WHITE RIVER BASIN.

Sixty miles below the Selwyn a large, muddy, turbulent river joins the Yukon 

from the west. The current of this stream is so swift that it crowds the lighter-

<*McConnell, R. G., The Macmillan River, Yukon district: Summary Kept. Geol. Survey Canada for 1902, p. 22.

fclbid. p. 20B.

"No accurate survevs of the entire Yukon have been made.
70 GEOGRAPHY AND GEOLOGY OF ALASKA.

colored waters of the main stream well toward the east bank. Both its valley 

and l)ed are wider than the Yukon at the junction. The muddy white color of 

this tributary led to its being named the White River" by Robert Campbell, an 

officer of the Hudson Bay Company, who discovered its mouth in 1850. The White 

River * has a general northerly course and its large tributaries are all from the east. 

Its drainage basin is irregular in outline and has an area of about 13,000 square miles, 

of which less than half is in Alaska. Its source lies in the northern lobe of the 

Russell Glacier, which occupies Skolai Pass, a break in the northern fork of the 

St. Elias Range, whence it flows eastward for nearly 40 miles in a broad gravel-filled 

valley nearly parallel to the St. Elias Range, and receives from it numerous small 

glacial tributaries. Gradually the valley narrows from 8 miles to 1 or 2 miles in 

width where it is crossed by the international Imundary, below which the stream 

is constricted in places, with a canyon-like character for about 20 miles, and then 

opens out to a broad lowland floored with gravel. This lowland has an area of 

1,000 to 1,500 square miles, and embraces not only the White River Valley, but to 

the west also a part of the upper Tanana Valley, and is extended eastward by the 

Gat valleys of some large tributaries. Below the lowland region the valley of the 

White narrows to 1 to 3 miles. Terraces bound its slopes as far as the mouth of the 

Klotassin, where they give way to occasional rock bluffs, which occur at intervals to 

its junction with the Yukon.

The peaks of the St. Elias Range, near the source of the White, are 10,000 to 

14,000 feet in altitude, but a short distance to the north the mountains fall off 

abruptly to the level of the plateau about o,500 feet which in turn slopes 

northward to less than 4,000 feet at the Yukon. The floor of the upper valley lies 

1,000 feet below the plateau, but the relief gradually increases downstream to over 

2,500 feet at the mouth.

The total length of the White is about 200 miles, of which 160 are in Canadian 

territory. The river is shoal throughout its course, and except in a few short 

rock-cut canyons has numerous channels, is studded with constantly shifting sand 

bars aud islands, and has all the characteristics of an overloaded stream. No current 

determinations have been made, but rough estimates show the velocity to vary from 

3 to 9 miles per hour.

Sixty miles from the Yukon the White forks. Though the two branches are 

of about equal sixe, the westerly one occupies the continuation of the lower valley 

and retains the name of the main river, while the easterly one is called the Klotassin. 

The Klotassin flows at right angles to the main valley, and probably rises close to 

the source of the Selwyn River. Twenty or 30 miles from its month the Klotassin 

receives the Donjek/ the largest tributary from the south. This stream haw a 

volume which probably nearly equals that of the White. It rises in a glacier of the 

St. Elias Range, flows northwesterly for 20 miles through a broad, gravel-floored

« The Lake Eluane Indians call White River tho Natzanka. The Tanana Indiana (Tetllng natives) eall It Kaslim, or 

Taztana.

6 Brooks, A. n., A reconnaissance in the Tanana and Wblte river basins In 1898: Twentieth Ann. Sept. U. H. Geol. 

Survey, pt. 7,1900, pp. 448-449. A reconnaissance from Pyramid Harbor to %aglc Pity, Alaska: Twenty-first Ann. Kept. 

U. H. Geol. Survey, pt. 2,1900, pp. 3.W-351.

o The old mapa of the White River basin show the Donjek as being directly tributary to the Whl4«, but recent explorwtlons by Canadian tmrveyors show this to be an error. It Is sometimes called the East Fork of White River.
YUKON BASIN. 71

basin which narrows down to a canyon, below which the valley broadens out, and is 

joined from the east by the Kluane River, the outlet of the lake of the same name. 

Near its mouth the Donjek receives the waters of Lake Wellesley through a small 

westerly tributary.

Lake Kluane lies in one of the depressions marking abandoned drainage 

courses which are traceable from Lake Dezadeash to the White. The lake is a 

beautiful sheet of water some 50 miles in length and 5 to 8 miles in width, 

surrounded by highlands rising to heights of 2,000 and 3,000 feet, in some places 

abruptly from a narrow, rocky beach, and in others from lowlands. The lowlands 

which skirt the north and south ends of the lake are dotted with clumps of trees, 

and interspersed with grassy meadows.

A small stream entering Lake Kluane from the east, has a valley which, 

too, forms a part of the former drainage sjT stem mentioned above. The Slims 

River, another tributary, finds its source in the Oconnor Glacier, which emerges 

from a valley in the St. Elias Range and discharges partly into White and partly 

into Alsek waters. The Nisling River, which joins the Donjek River some miles 

below the mouth of the Kluane, has its headwaters near those of the Nordenskiold, 

a tributary of the Lewes, and flows through a broad valley whose slopes are often 

terraced." The Klutlan, confluent to the White a few miles below the international 

boundaiy, emerges as a large stream from underneath the Klutlan Gla'cier, about 10 

miles south of the main valley.

The swift waters of the White River make it unnavigable for steamers, and it 

can be traversed in small boats only with great difficulty. W. J. Peters and the 

writer, in 1898, ascended the White about 100 miles in canoes, and this is probably 

the highest point which has been reached by an upstream boat trip, though several 

prospectors have built boats near the head of the river and made the journey to the 

mouth without serious difficulty. The natives occasionally make the downstream 

trip in improvised skin boats, but always return by land.

STEW ART RITEK.

The Stewart River joins the Yukon from the north, 10 miles below the mouth 

of the White, and is described by McConnell as follows:*

''The Stewart is one of the main tributaries of the Yukon. It rises in the unexplored Pacific-Arctic watershed ranges tying between the heads of the Peel and Pelly 

rivers, and flows in a general westerly direction toward the Yukon Valley. From 

Frazor Falls to its mouth, a distance of nearly 200 miles, it is a large stream, seldom 

le^s than 150 yards in width, and often more than double this size. It is navigable 

throughout the season by ordinal1 }" shallow-draft river steamers all the way to the 

Frazor Falls. From the Mayo to its mouth the current flows from 3 to 5 miles 

an hour, with occasional accelerations on the bars. Above Mayo River the current 

decreases to a rate of '2 to 3 miles an hour, and bars are almost entirely absent. 

At the Frazer Falls the Stewart flows for a third of a mile with great velocity 

through a narrow canyon bounded by vertical walls of hard quartzose schist. The 

word "falls"' is a misnomer, as the grade in the canvon is fairly uniform and the

n Tyrrell, J. B., The Yukon district: Summary Bcpt. Geol. Survey Canada for 1889, p. 40.

'< McConnell, R. G., The Yukon district: Summary Kept. Gcol. Surrey Canada for 1900, pp. 39 and 40.
72 GEOGRAPHY AND GEOLOGY OF ALASKA.

total descent was estimated to be only 30 feet. Above the falls the river is interrupted by occasional short riffles for several miles, but farther up its course is 

reported to be clear to the main forks, a distance of about 60 miles, and up the 

north branch for a considerable stretch beyond. The east branch is reported to be 

a rapid stream, constantly interrupted by rapids and canyons. * * *

"The country bordering the lower part of the Stewart River is nearly everywhere of a mountainous character, and may be described as a high plateau deeply 

dissected by a multitude of wide and often interlocking valleys. The hills project 

above the valleys in isolated masses, in irregular-shaped groups, and in well-defined 

ranges. The outlines are generally rounded and the elevations range from about 

2,500 to 4,000 feet above the main valleys. The lower slopes are clothed with a 

forest of spruce, poplar, birch, willow, and alder. Above a height of about 2,500 

feet the surfaces are usually bare. The bottom lands of the Stewart often exceed 

2 miles in width and are seldom less than a mile, and those of many of the tributaries, 

notably Crooked River and Lake Creek, are even wider. Below the mouth of Clear 

Cieek the Stewart has cut a comparatively narrow rock-walled channel through the 

bottom of the older valley. The deepening of the valley is evidently due to the same 

eievatory movement that affected the Klondike region and evidences the wide extent 

of that uplift."

SIXTYMILE CREEK.

The Sixtymile Creek heads on the Alaskan side of the international boundary, 

flows southerly and easterly, and empties into the Yukon near latitude 63° 30'. 

The valley is incised in the plateau" similar to the other tributaries of the Yukon 

already described. The gold placers in its upper basin have long been reached 

by trail from the Fortymile Creek, but recently the Canadian authorities have 

constructed a road from the Yukon to the boundary.

KLONDIKE RIVER.

The name Klondike, which has become a household word nearly all over the 

world, is often indiscriminately used to designate all of Alaska and adjacent parts 

of Canada, though it rightly applies to only a few hundred square miles of the 

Canadian Yukon basin.

The Klondike River enters the Yukon from the east near the sixty-fourth 

parallel of latitude. It is a small stream that would hardly deserve description 

were it not for the world-wide fame which its placer fields have attained. These 

rich gold deposits He in both the Klondike and Indian River basins, which are 

tributary to the Yukon within a few miles of each other. Dawson, with a 

population of 5,000 or more, located on the Yukon at the mouth of the Klondike 

River, is the distributing point for this mining district. The following quotation 

from McConnell describes this region, which lies entirely within Canadian territory:

' The Klondike region* may be described as a high plateau, cut in all directions 

by numerous deep and wide branching valleys. The general aspect, viewed from 

one of the higher elevations, is rough and hilly but fairly regular. The outlines are 

rounded, the slopes even, 'and sharp peaks are notably absent. The region is really

a McConneli, R. G., Summary Rept. Geo). Survey Canada for 1901, p. 34.

fcMcConnell, R. G., Preliminary report on the Klondike gold fields: Geol. Survey Canada, No. 687, pp. 6 and 7.
YUKON BASIN. 73

formed of a system of long, branching, round-back ridges, separated by deep, wide, 

flat-bottomed valleys. Most of the ridges, speaking broadly, center in the Dome, 

the highest eminence in the district.

"The ridges have an average elevation above the valley bottoms of 1,500 feet. 

They are deeply gashed on both sides by steep gulches and are surmounted by numerous bare, rounded prominences separated by wide depressions. The3" radiate in irregular curved lines from the Dome and descend gradually, throwing off branches at 

intervals, toward the main water courses.

"The elevation of the ridges and surmounting hills is fairly uniform. The 

Dome has an elevation of about 4,250 feet above the sea, 3,050 above the Yukon at 

Dawson and about 500 feet above the ridges at its base. It is not conspicuously 

higher than other hills in the neighborhood, and the gradual decrease in elevation 

outward along the ridges is scarcel}*- noticeable to the eye.

"The valleys are wide and flat-bottomed in their lower parts, but gradually 

narrow toward their heads into steep-sided, narrow gulches which terminate 

abruptly in steep, rounded, cirque-like depressions cut into the sides of the ridges. 

The valle}T flats are marshy, partly wooded, and wider on the Indian River than 

011 the Klondike slope. The flats bordering the lower parts of Dominion Creek 

have a width in places of nearty half a mile.

"The streams are small, seldom exceeding 15 feet in width, even at their 

mouths, and along the productive portions of the valleys are much less. The}' fall 

rapidly near their heads, but in descending the valleys the grade soon diminishes, 

and in the case of Dominion and other Indian River creeks does not exceed, in the 

lower parts of the valleys, 25 feet to the mile. The Klondike streams are somewhat 

.steeper, the grade averaging in the lower parts of the valleys about 40 feet to the 

mile.

"The Klondike River is a large, rapid stream, averaging about 150 feet in 

width. It is interrupted bj- frequent bars, and has a fall of from 12 to 15 feet to 

the mile. Indian River, which forms the southern boundary of the district, is a 

much smaller stream. It has a width of from 20 to 40 3T ards, but is very shallow, 

the water on the bars seldom exceeding a few inches in depth."

FOHTVMILE BASIX.

Fortymile Creek, confluent to the Yukon from the west about 40 miles above 

the boundary, is the main stream of a dendritic drainage system which reaches 

far to the southwest toward the Tanaua. Its basin lies close to the international 

boundary, and a small part of it is in the Yukon .Territory.

The upper tributaries of this system lie in broad, shallow valleys with walls 

rising gently for 1,000 feet to the level of the plateau, and with flat floors over 

which the streams meander sluggishly. These headwater basins are drained by 

channels" sharply incised in an older valle3' floor which has been almost entirely 

eroded. At the forks, 75 miles from the mouth, the valley floor of the Fortymile 

lies about 2,000 feet below the plateau, and the river here flows through a narrow 

canyon* which is incised in an older valley floor, the remnants of which now form

"Goodrich, II. B., Recent warpiugs [in the Yukon district], as shown by drainage peculiarities, Eighteenth Ann. Rept. 

T. S. Geol. Survey, pt. S, 1898, pp. 270-289.

t> See Fortymile atlas sheet, C. S. Geol. Survey.
74 OEOGEAPHY AND GEOLOGY OF ALASKA.

benches 600 feet above the present water level (PI. XVII, U). This older valley 

floor has a width of a mile or more, and has been traced by the writer downstream 

as far as the boundary, below which no observations have been made. About 25 

miles from its mouth Fortymile Creek descends precipitously through a rock canyon 

to the level of the Yukon. Below this canyon the valley opens out and the current 

becomes sluggish.

In the lower 60 miles of its course the Fortymile descends about 400 feet, and 

is, in fact, a series of small rapids alternating with reaches of smoother water. 

While ordinarily not regarded as navigable, a steamer has been taken up it for 20 or 

30 miles, but more commonly supplies are transported to the placer camps within 

its basin by a species of long, narrow craft known as a "Yukon poling boat."

Fortymile Creek has long been one of the routes of communication between 

the natives of the upper Tanana and the Yukon. These crossed the divide, and, 

building skin boats or rafts on Fortymile, descended that river to the Yukon and 

returned by land.

SMALT/ TRIBUTARIES OF THE UPPER YUKON.

Between the international boundary and the flats the Yukon receives many 

tributaries from both sides, most of which are small. Seventymile Creek enters 

the Yukon from the west, about 30 miles below the boundary. In its lower 10 

miles it meanders through a broad, flat-bottomed valley, while the upper portion 

of its valley is sharply incised in an older valley similar to Fortymile.

Tatonduk River enters the Yukon from the east, a few miles below the Seventymile, and its headwaters are close to those of the Porcupine.'8 The Tatonduk Valley 

is made up of a succession of broad, flat basins, connected by sharply cut canyons. 

Charlie River, which joins the Yukon from the west a few miles below the Tatonduk, has not been surveyed.

The chief tributaries of the upper Yukon, besides its two parent streams, the 

Lewes and the Pelly, are the White, Stewart, and Fortymile, with also a host of 

smaller ones. The upper Yukon flows through a steep-walled, rather narrow, and 

somewhat winding valley, and, like most of its tributaries, lies entirely in the 

plateau province. The Lewes rises on the inland slope of the Coast Range, the 

White on the flank of the St. Elias, while the Stewart has its source in the 

Rockies.

YUKOX FLATS.

OENERAL DESCRIPTION.

The Yukon Flats are great lowlands which stretch for 200 miles along the 

middle Yukon, with a width of 40 to 100 miles; their topograph}' has already 

been described (PI. XIV, A). Within the flats the river makes the great bend 

which changes its course from northwest to southwest.

No surveys have been made of this part of the river, but in places the 

stream probably broadens to 10 and possibly 20 miles, and includes an intricate 

network of waterways, with some channels having a perceptible if not strong

a Ogilvie, William, Exploratory Survey of Part of trie Lewes, Tatonduk, Porcupine, Bell, Trout, Peel, and Mackenzie 

rivers, 1887-88, Ottawa, 1890. MoConnell, K. G., Report on an exploration in trie Yukon and Mackenzie basins, N. W. T.: 

Ann. Kept. Geol. Nat. Hist. Survey Canada, new series, vol. 4, 1890, pp. 1D-163D, map sheet No. 9.
YUKON BASIN. 75

current; while others are sloughs, with almost stagnant water. The shifting 

waterways form many oxbow lakes. These channels are separated by sand bars 

and islands, for here, where the river is ever changing, now courses are constantly 

being cut and old ones abandoned and filled up by the silts of the heavily burdened 

waters. This action of the river makes navigation an ever-changing problem to the 

steamboat pilots, who, on account of the absence of charts, are entirely dependent 

on knowledge acquired by experience. During the Klondike rush Indian pilots 

steered most of the steamers, but these have now been largely replaced by white 

men trained on the Mississippi under similar conditions of navigation.

From the steamer deck the Yukon Flats present a monotonous expanse of sand 

bars and low, densely forested spruce islands, through which the boat follows a 

tortuous channel among a bewildering maze of tributary and distributary watercourses, with an occasional glimpse of the distant rim of the plateau which surrounds the lowland. The presence of man in this dreary tract is made manifest only 

in the clearings from which the spruce has been cut for fuel, or in the occasional 

small Indian settlement, or wood-chopper huts. At low water 10 or 15 feet of 

frozen silt bank is exposed, while during floods the river is almost even with the 

surface of the islands.

PORCUPINE BASIN.

The Porcupine River, one of the larger tributaries of the Yukon, and 

'confluent at the groat bend 3 miles north of the Arctic Circle, has its source in 

latitude 65° 80', only 60 miles from the Yukon. For over 100 miles it keeps a 

northeasterly course until, impinging on the inland front of the Rocky Mountains, 

it turns abruptly to the west and continues in a westerly and southerly direction 

to its junction with the Yukon. Its basin has an area of nearly 80,000 square 

miles and is for the most part in Canadian territory. It has been explored by 

Og-ilvie« and McConnell.*

Above the great bend the Porcupine has a broad valley 1 to 3 miles in 

width, with gentle slopes, and cut to a depth of 1,000 feet or more below the 

plateau level. Bell River, a small eastern tributary confluent at the bend, is 

connected by a portage across the mountains with Rat River, a tributaiy of the 

Mackenzie. Below the bend the valley is usually wide, except where the river 

flows through small rock canyons, which are incised below an old valley floor. 

In the so-called "Ramparts," near the international boundary, the valley becomes 

contracted and assumes a canyon-like character, and this continues for 50 miles 

to the Yukon Flats, in which the river becomes a many-channeled, comparatively 

sluggis'h stream and joins the Yukon through several channels. The Old Crow 

River, the largest tributary, is confluent from the north, a few miles above the 

Ramparts, and has its source in the Arctic Yukon watershed. The Salmon 

River, also from the north, joins the Porcupine within the flats, but its headwaters probably do not reach the Arctic divide, while the drainage from the 

south is brought in by the Bluefish River above and the Black River below the 

Ramparts.

nOgilvic, William, Exploratory Survey of Part of the Lewes, Tatonduk, Porcupine, Bell, Trout, Peel, and Mackenzie 

rivers, 1887-88, Ottawa, 1890.

*>McConnell, R. G., Report on an exploration in the Yukon and Mackenzie basins, N. W. T.: Ann. Rept. GeolNat. Hist. Survey, Canada, new series, vol. 4, 1890, pp. ID-1631).
76 GEOGRAPHY AND GEOLOGY OF ALASKA.

McConnell 0 states that the Porcupine is navigable for small steamers above 

the Ramparts, and records currents in this part of the river of from 3 to 5 

miles per hour. Turner* reached a point 39 miles below boundary with steamer 

during the low stage of the water in August, and reports that except at low 

water a steamer could easily reach the boundary. The Hudson Bay Company 

had in 1847 established the route from the Mackenzie to the Yukon by way of 

the Bell and Rat River portage, which for hundreds of miles is probably the 

only low pass through the Rocky Mountains. This has therefore been a wellestablished route of communication of white traders for upward of half a 

century, and must have been known to natives long before.

CHANDLAR BASIN.

The Yukon has an almost due westerly course for nearly 20 miles from the 

mouth of the Porcupine, and then makes a sharp bend to the southwest, and 

here the Chandlar River c is confluent from the north through a number of tortuous channels. This river a has its source well within the Endicott Range, in 

which it has a general southerly course, while in the flats it flows about east. 

In the mountains the Chandlar Valley is from 1 to 2 miles in width, and the 

walls rise steeply to altitudes of 3,000 feet above the river. Above the sixtyeighth parallel of latitude the river has incised a new channel to a depth of 100 

feet in an older valley floor, while below the river widens out and for about 50 

miles meanders over an alluvial plain, which occupies a basin of varying width 

and whose surface abuts abruptly against the steep valley walls. Chandlar Lake 

about 10 miles in length, occupies the lower end of this basin, and a few miles 

below its outlet the valley contracts and the gradient of the stream becomes 

greater; but 20 miles below, at the southern limit of the mountains, the valley 

broadens and for 50 miles farther is incised into the plateau, which stands at 

about 3,000 feet, and the walls have gentle slopes. The river here receives a number of important tributaries from the north and west, which have their sources 

in the Endicott Mountains. Its entire basin has not been surveyed, but probably 

includes about 10,000 square miles.

Near the sixty-seventh parallel of latitude the Chandlar enters the Yukon Flats, 

where it usually has diverse channels, with many sand bars and islands, and must 

maintain a considerable current, as it descends about 300 feet in a distance of 40 

or 50 miles (PI. XIV, A). The Chandlar, navigable for steamers for only a few 

miles, can be ascended by canoe for about 200 miles, though portages are necessary 

around the rapids near the foot of the lake. Portage routes connect its upper 

waters with the Koyukuk basin.

RIRCH CREEK.

Birch Creek, which enters the Yukon from the east about 20 or 30 miles below 

the mouth of the Chandlar and in the lower 75 miles of its course, meanders across 

the Yukon Flats, where it receives several tributaries from the west. Its general

a McConnell, R. G., Report on an exploration of the Yukon and McKensie basins, N. W. T.: Ann. Report Geol. 

Nat. Hist. Survey Canada, new series, vol. 4, 1890, p. 129D.

!>Turner, J. H., The boundary north of Fort Yukon: Nat. Geog. Mag., vol. 4,1892, pp. 189-190.

o On some old maps called the Gens de Large River.

<i Schrader, F. C., A reconnaissance along the Chandlar and Koyukuk rivers, 1899: Twenty-first Ann. Rept. T". S. 

&eoL Survey, pt. 2, 1900, pp. 464-467.
YUKON BASIN. 77

course is northwest, and near latitude 65° 30' it is only 15 miles distant from the 

Yukon, where it bends from the south, and its headwater drainage channels, which 

lie in a broad valley, interlock with tributaries of the lower Tanana. Birch Creek 

is navigable for small steamers only in the flats, and its importance rests solely on the 

placer gold which has been mined in its basin.

HOSIANA RIVER.

This stream joins the Yukon nearly opposite Birch Creek. Its headwaters are 

known to reach to the Koyukuk divide, though its basin has not been surveyed. Its 

valley is one of the routes followed "by prospectors in reaching the Koyukuk from 

the Yukon.

BEAVER CREEK.

This stream, which is unnavigable, enters the Yukon from the south about 20 

miles below the mouth of Birch Creek. Its headwaters are dovetailed with streams 

flowing into Birch Creek and with tributaries of the lower Tanana. Beaver Creek 

flows northeasterly as far as the point where it leaves the uplands; it then makes a 

rig'ht-angled bend to the west and south, and for about 20 miles skirts the escarpment 

which marks the southern limit of the Yukon Flats. Within this lowland it is 

sluggish and has a tortuous course. The right-angled bend in the flats is paralleled 

by a similar bend in Birch Creek, and these two striking changes in direction are 

probably due to the same cause.

DALL RIVER.

The Dall River enters the Yukon from the north, a few miles above the Ramparts. It is described by Mendenhall as follows:

 'The Dall River* joins the Yukon 9 miles above Fort Hamlin, near the western 

edge of the great Yukon Flats, the lower 50 or 60 miles, about half the length, of 

Dall River lying within these, although near their western limit. The country is 

utterly devoid of relief and contains a great number of sloughs and ponds, many of 

them old and abandoned courses of the Dall and its tributaries, so that during periods 

of high water the entire area is flooded and the course of the river is marked only as 

a lane through the spruces and willows. At such times it may be difficult to find land 

areas of sufficient size for camping purposes, and transportation by other means than 

boats is out of the question.

"For about 25 miles below Dall City the river, although not in the Yukon Flats 

proper, wanders back and forth across a rather broad valley, bounded at some distance 

on either side by hills which approach the river and increase in height toward its 

source. Near the upper end of this stretch a branch almost equal in volume to the 

main stream joins the latter from the north. Dall Citj-, so called, consists of two or 

three abandoned prospectors' cabins, and lies at the point where Dall River is 

crossed by the overland trail at the entrance to the canyon-like upper portion of the 

valley. Our party did not traverse this canyon, since it is impassable for small 

boats, as it has a fall of nearly 1,000 feet in an air-line distance of less than 10 miles.

" The general divide between the Dall River and the Koyukuk stands at between 

3,000 and 3,500 feet above tide, the gap at the head of the Dall River being cut 1,500

«Mendenhall, \V C., Reconnaissance from Fort Hamlin to Kotzebue Sound, Alaska: Prof. Paper U. S. Geol. Surrey 

No. 10, 1902, pp. 21 and 22.

17211 No. 45 06 6
78 GEOGRAPHY AND GEOLOGY OP ALASKA.

feet below this level. The hills immediately to the north of the Dall River are broad, 

smooth, rounded ridges, standing above timber line, and very generally devoid of 

all vegetable growth except hardy lichens. An area of much more rugged forms, 

but standing at approximately the same elevation, lies north and west of the portage 

in the direction of Fish Creek and Jim River.

"A conspicuous valley leads northeastward from a point north of Dall City, and 

is probably drained by the Hosiana or Swift River, which empties into the Yukon 

between the Dall and the Chandlar."

The Yukon receives many other streams within the flats, but these are not of 

sufficient size to call for special description, and, moreover, as the region has not 

been surveyed, little is known of them.

SUMMARY.

Within the Hats the Yukon receives only three important tributaries the 

Porcupine, Chandlar, and Dall rivers. The Porcupine drains a large area lying 

east and southeast of the great bend of the Yukon, which is entirely within the 

plateau province, but it receives some drainage from the western flank of the 

northern Rockies. The Chandlar rises within the Endicott Mountains, which 

form the Yukon-Arctic watershed, then flows through a part of the plateau 

province. Two smaller streams Birch and Beaver creeks contribute most of 

the drainage from the south, and the Dall River rises within the plateau province 

and after crossing a part of the lowland enters the Yukon from the north.

BAMl'AHT KEGION.

Near the sixty-sixth parallel of latitude the flats end abruptly at a scarp 

which forms the northern boundary of a part of the plateau. This stands 

between 1,800 and 2,000 feet above sea level, and is often called the Lower 

Ramparts of the Yukon. The Yukon traverses this upland by a narrow, somewhat winding valley, whose walls often rise rampart-like, either directly from 

the water or from a narrow terrace (PI. XVI, A). The stretch of the valley, 

between 110 and 130 miles long (measuring around the bends) and one-half mile 

to 3 miles wide, continues unbroken from the Yukon Flats to the mouth of the' 

Tanana. The general course is southwesterly, but it has many windings which 

strongly suggest incised meanders, the relics of a former flood-plain condition.

The Rampart region with the broad, sweeping curves of the river and the steep 

valley walls, clothed with spruce, cottonwood, and birch, varied by bare cliffs, is the 

most picturesque part of the Yukon. The Russian Lieutenant Zagoskin, in 1848, 

reported the Yukon as unnavigable above the lower end of the Ramparts, though 

its ascent and descent by steamer is attended by much less difficulty than in any 

other part of the river, for the current probably does not exceed 5 or 6 miles per 

hour, and there are few shifting sand bars to contend with. Tn this region a few 

streams are confluent from both north and south, but none is large enough to be 

called a river, though one, Ray River, passes as such. All of these water courses 

flow in normal valleys, broad, gravel-filled near their mouths, narrowing upstream 

to sharply trenched, rock-floored canyons toward their headwaters. The largest 

are Hess, Minook, and Shevlin creeks from the south and Ray River from the 

north.
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 45 PL. XVI

A YUKON VALLEY IN RAMPARTS. 

Showing abrupt slope of valley wall from water.

B, YUKON VALLEY AT EAGLE.
YUKOJS BASIN. 79

LOWER YUKON.

GENERAL PESCKIPTION.

Under the name lower Yukon is included the portion of the river which is 

between the Ramparts and the sea, and which, measured along the bends, has a 

length of about 800 miles.

The Ramparts end at the mouth of the Tanana, where there is an abrupt change 

in the contour of the valley. The gorge suddenly opens to a broad lowland, 

which along the Yukon is 15 to 20 miles in width, but stretches up the tributary 

Tanana Valley for a distance of 200 miles, with a width of 20 to 100 miles. The 

northwestern boundary of the valley is a series of low mountains whose base the 

Yukon hugs. The southern wall is 15 to 20 miles distant near the Tanana, but 

gradually approaches downstream, thus reducing the width of the valley. Throughout its course to the head of the delta the Yukon continues to skirt its north bank, 

and though the width of the valley varies it is never less than 2 or 3 miles, while 

the river itself flows through many channels and is broken by numerous islands 

and sand bars.

The general trend of the lower Yukon is west for an air-line distance of 200 

miles, then south-southwest for 200 miles to another great bend below, and then 

west-northwest to the head of the delta (PI. XXXIV). TVell-deiiried north and 

west walls of the valley continue nearly to the head of the delta, but 100 miles 

above the delta the south wall gives way to the lowland coastal plain, with here and 

there an occasional isolated hill. There are no topographic surveys of the lower 

Yukon, but the relief is probably not much more than 1,000 feet.

The delta begins near the sixty-third parallel of latitude where the river divides 

into a number of divergent channels which tind their way to the sea with general 

northerly and northwesterly courses. The Apoon Pass" is the northernmost and 

the Kwikluak Pass the most southerly of these waterways which reach the open sea 

at points about 75 miles apart in an air line and 40 or 50 miles from the head of the 

delta. An intricate maze of waterways lies between the two channels, some of which 

flow chiefly to the Bering Sea; others connect with such channels, but many are 

blind sloughs affected only by the ebb and flow of the tide. The inter-stream areas 

not more than 10 feet above low tide are swampy and dotted with innumerable small 

lakes. Here, as in the flats, the Yukon is constantly shifting its channels, the changes 

are brought about largely by the current and tides, but are aided by the scouring of 

the ice which accumulates in the delta after the break up in the spring- and which 

forms dams that cause new channels to be cut and old ones to be silted up.

Throughout its course the Yukon is a mud-laden stream, but it is more heavily 

charged with sediments above the flats than below, for during its comparatively 

sluggish course throughout this lowland bolt it drops a part of its load. The siltladen waters of the lower river are making rapid inroads on the sea by extending 

the delta. Russell made the only attempt on record to ascertain the proportion of 

sediment held in suspension by the Yukon waters, and his determinations were made 

on the lower river and in midsummer. In winter the waters are said to be perfectly 

clear.

« Jarvis, D. H., Alaska coast pilot notes on the Fox Island 1'as^es, Unalaska Bay, Bering Sea, and Arctic Ocean as far 

as Point Barrow: Bull, U. S. Coast anrl Geodetic Survey Xo. 40. See also Charts Xos. 9373 and 9374, United States Coast and 

Geodetic Survey.
80 GEOGRAPHY AND GEOLOGY OF ALASKA.

Se<li>iient in the water of the Yukon.«

Locality. Date.

Below mouth of the Tanana:

Lofka _.__._..---.-.__.-__..._-..----_-.---.-------.--------.-.

Nulato....._...-..-...--.--...---..-...-.-...--------------- ....... July 24,1889

Nowikakat...--.-..-..--.----.----.---_----.--................ .....I July 25,1889

Above mouth of the Tanana:

Entrance of Lower Ramparts ....................................

Five miles above Lower Ramparts................................

July 22,1889

July 27,1889 

July *8,1889

Grams in 

a liter.

0.9817

1.1147

.7783

. 2754

.2078

<z Russell, I. c., Surface geology of Alaska: Bull. (ieol. Soc. America, 1889, vol. 1, p.116.

Though no accurate data are available concerning the rate of the seaward growth 

of the Yukon Delta, it is evident that this reclamation is going on very rapidly.

The following note on the composition of Yukon water has been published 

by F. W. Clarke:"

 'On June 14, 1904, Mr. F. L. Hess, of the United States Geological Survey, 

collected, at nry request, a sample of water from the Yukon River. The sample 

was taken in midstream, above the town of Eagle, a little below north latitude 65°, 

and nearly on the boundary between Alaska and Canada. It was fairly but not 

absolutely clear, and contained 0.1565 gram of suspended inorganic sediment, as 

weighed after ignition. The soluble inorganic constituents of the water are given 

in the subjoined analysis by Mr. George Steiger, and there was also some org-anic 

matter undetermined. The CO3 represents normal carbonates only, in order that the 

water may be compared with others which are stated in similar terms; the silica 

and alumina are conventionally reported as present in colloidal form.

p/ )

SO4 ........................................

CL-... ..--.-----------.--------------------

NOg... ..........-.-..-.----........-....-..

PO

Ca .........................................

Mg..... ....................................

Na ......... ................................

K. -.---...--...--.. ........................

NH4 ..... ........ ...........................

SiO2 ... ......... ........................ ....

A12O,- -------------------------- ------------

Fe O

Parts per 

million.

45.1 

10.5 

.4

21.7 

4.6 

6.0 

Trace.

7.6 

1.8

97.7

Percentage of total solids.

A. Yukon.

46.16 

10.75 

.41

22.21 

4.71 

6.14 

Trace.

7.78 

1.84

100. 00 

97.7

B. St. Lawrence.

44.43 

11.17 

2.41

20. 67 

6.44

4.87

10. 01

100. 00 

148.0

C. Rhine.

47.06 

12.61 

4.17

.28 

27.36 

5. 57

1 2. 69

. 17 

1 .09

100. 00 

178.0

D. Baikal.

49.85 

6.93 

2.44 

.21 

.72 

23.42 

3.57 

j 5.85 

I 3.44 

.08 

2.03 

t 1.46 

L........

100.00 

69.0

a The water of the Yukon: Jour. Am. Chem. Soc., vol. 27,1905, pp. 111-113.
YUKON BASIN. 81

"The CCX 'half combined' in the Yukon water is 20.5 parts per million.

"The columns which give the percentage composition of the mineral matter 

dissolved in the river water are peculiarly useful. They enable us to compare different 

waters with one another independently of the great variations which they exhibit in 

respect to dilution. Out of a large number of analyses of river and lake waters, 

which I have reduced to uniform standards, the following approximate most nearly 

to the Yukon:

"B. The St. Lawrence, opposite Montreal. Analysis by Norman Tate. The 

high silica is due in part to the influence of the Ottawa, and the chlorine may 

represent pollution.

"C. The Rhine, at Cologne. Average of four analyses by Vohl. The high 

chlorine is again noticeable.

"D. Lake Baikal, Siberia. Analysis by Schmidt.

"The Yukon, then, at least where the sample was taken, is a fairly typical 

calcium carbonate water with a remarkably low proportion of chlorides. It belongs 

to a large and well-defined group of natural waters, and it is desirable that other 

rivers of the far north should be examined for comparison with it. Such rivers 

probably represent the minimum of contamination through human agency, and their 

composition is therefore particularly significant for geological discussion. Rivers, 

however, vary in composition from time to time and place to place, and a single 

analysis does not give all the information that is needed. I hope that later samples 

from other points on the Yukon may be available for analysis, in order that its 

possible variations may be discovered and recorded."

Though the Yukon delta properly includes only that part of the coastal plain 

included between the distributaries of the river, the broad lowland which embraces 

the deltas of the Yukon and the Kuskokwim has an extreme breadth of upward of 

2()0 miles, and might well be grouped with the delta flats. There can be no doubt 

that at some time a part of the Yukon waters found its way across these lowlands 

and deposited the sediments by which they were made to encroach upon the sea. 

This region embraces a flat which is but a few feet above tide water and is drained 

by sluggish meandering rivers and dotted by many lakes. Its smooth surface is 

interrupted here and there by low, isolated, hills, while the shore line is broken by 

inlets and tidal lagoons. At low tide this low coastal plain is extended a long 

distance seaward by mud flats.

The lower Yukon offers no serious menaces to navigation by river steamers, 

but like the upper river it is uncharted, and except in the delta mouth its channels 

are unbuoyed. From the mouth of the Tanana to the delta the river flows through 

two or more channels, and, in places, these diverge so as to include a breadth of 

'2 miles or more, dotted by islands and sand bars. Here, too, the channels are 

constantly shifting, but the greatest depth of water is usually found near the north 

and west bank. The current is estimated at from 1J to 4 miles an hour, and the 

influence of the tide reaches to the head of the delta.

In the delta steamers usually follow the northernmost waterway called Apoon 

Pass, for this has a well-defined, though shifting, channel through which i feet 

can be carried at mean low water. At the mouth of the pass the water shoals
82 GEOGRAPHY AND GEOLOGY OF ALASKA.

to 1^ feet at low water and steamers are forced to take advantage of high tide to 

cross the bar. From the Apoon mouth the river steamers make their way across 

a stretch of about 60 miles of open sea to St. Michael Island, which possesses the 

only harbor, and that but a poor one, -along many hundred miles of the coast, and 

here the transfer to ocean steamers is made. The passage from the mouth of the 

river to St. Michael in the flat-bottomed river steamers can be made in safety 

during calm weather, but at other times is not unattended with danger.

The scenery of the lower Yukon offers but little of interest to the traveler. 

The mighty river, with its dark-yellow waters, is not without its grandeur, and 

the rounded valley slopes, dotted with spruce and deciduous trees, are not without picturesqueness, but for hundreds of miles there is almost no change in the 

aspect of the landscape. The upper reaches of the lower Yukon are heavily forested, but as the sea is approached the trees become more scattering, and finally, 

a few miles above the delta, give way entirely to the tundra, with its dreary, 

monotonous view. Inland the moss- and grass-covered lowlands stretch almost 

unbroken to the horizon, except for distant, rounded highland masses, while seaward there is no break in the lowland, and its smooth surface merges with the 

plain of the sea. The delta supports a large, though migratory, Eskimo population, which finds its way about among the intricate waterways in large skin 

boats (oomiaks) and kayaks, and is almost entirely dependent on the sea for food.

TANANA BASIN."

The Tanana River, the longest tributary of the Yukon whose basin lies 

entirely in Alaska, empties into the latter just where it emerges from the Hamparts. The Tanana Valley, about 400 miles long, trends northwesterly parallel 

to the main stream above the big bend, and drains ail area of probably 25,000 

square miles. The Alaska Range bounds the basin on the south and is the breeding ground of the glaciers, from which most of the southern tributaries of the 

Tanana spring. The headwaters of the many tributaries from the north interlock with streams which flow directly into the Yukon above the Ramparts.

Near latitude 63° and longitude 142° the river breaks into two tributaries 

of about equal volume. For the eastern, which follows the extension of the axis 

of the main valley, the name Tanana was retained in the reports cited; to the 

western was given the name Nabesna.'' Schrader, however, who has more recently 

visited this region, reports that usage among both prospectors and natives has 

definitely assigned the name Chisana to the east fork, and this designation will 

here be adopted and the name Tanana limited to the river below the junction of 

the Chisana and the Nabesna.

A large glacier, which lies on the north slope of the Skolai Mountains, gives 

rise to the Chisana, which, near its source, is joined by two glacial tributaries nearly 

as large as itself. These three streams occupy a broad basin, which is nearlv 5,000 

feet above the sea, and is bounded on the south by the Skolai Mountains and on the

"Brooks, A. H., A reconnaissance in the Tanana and White river basins in 1898. Twentieth Ann. Rept. I". S. Geol. 

Survey, pt. 7, 1900, pp. 449-451. A reconnaissance from Pyramid Harbor to Eagle City: Twenty-first Ann. Kept, I* b 

Geol. Survey, pt. 2, 1900. pp 351 and 352.

fr Formerly useol b.v the upper Tanana natives to designate tlie main river, but its use 111 this connection seems long 

since to have been abandoned.
YUKON BASIN. 83

north by the Nutzotin Mountains. On the south a broad, flat depression 1,000 feet 

above the floor separates the basin from the White River drainage to the east, while 

on the west a somewhat narrower pass, with an altitude of 5,800 feet, divides it 

from the Nabesna drainage. Leaving this basin the Chisana traverses the rugged 

Nutzotin Mountains in a narrow, steep-sided valley, and here receives a number of 

glacial tributaries. This canyon is about 15 miles long, and in it the river descends 

nearly 800 feet. Below it opens out, bends to the north, and about 25 miles from 

its source the river debouches on the broad lowland which is coextensive with that 

of the middle White and the upper Tanana. The Chisana crosses this lowland and, 

making a right-angled bend to the northwest, hugs the foot of the north wall of the 

valley to the junction with the Nabesna. Several streams are tributarv to the 

Chisana from the east and north within the lowland. These flow in broad, flat, 

gravel-filled valleys, with low gradients.

The Nabesna springs from a large glacier on the north slope of the Wrangell 

Mountains, flows northeasterly in a broad valley for 20 miles, where it is joined by 

other glacial streams, and then traverses a narrow, steep-walled valley in the Nutzotin 

Mountains, whose summits rise 3,000 to 4,000 feet above the water. In about 20 

miles the intermontane part of the valley widens out, and 10 miles farther the 

Nabesna Valley merges with the lowland, crosses to the north wall of this lowland, 

and meets the Chisana flowing from the east.

The Tanana Valley falls into three physiographic provinces, which can be 

conveniently used for purposes of description. The broad lowland near the head is 

called the " upper Tanana;" the constricted part of the valley between the Tetling 

and Delta rivers is termed the "middle Tanana," while the broad portion between 

the Delta and the mouth will be designated the "lower Tanana."

The head of the Tanana at the junction of the Chisana and the Nabesna rivers 

is in a broad lowland, gravel floored, with plain surface, but here and there interrupted by small hills and knolls. This lowland slopes northward from the base 

of the mountains to the north valley wall with a sufficient grade to give the streams 

which follow it a swift current. The flat is extended east by a broad depression 

which connects it with the lowland of the middle White River, alre^uty described. 

It has an extreme width of 25 miles, and the part drained by the Tanana River 

is nearly 60 miles long.

Ten miles below the junction of the Chisana and Nabesna the Tanana enters 

the constricted part of its valley, which has a width of about 2 miles. Hero the 

stream is called the middle Tanana, and receives the Tetling River from the 

south. The Tetling is a clear-water stream draining several lakes the largest 

about 2 miles long which lie near the southwestern margin of the lowland and 

which probably owe their origin to the damming of the former course of the 

Tetling by the delta deposits of the Nabesna. One of the trails from the Copper 

River reaches the Tanana at the mouth of the Tetling River.

The middle Tanana Valley is formed by a series of connecting basins which 

are parallelograimnatie in outline, and are incised to a depth of 2,000 to 2,500 feet 

below the upland surface. These basins are bounded by escarpments whose 

windings give a succession of elbow-like forms to the vallej' walls, which fall into 

two parallel systems, outlining a series of parallelograms. The river, which hugs
84 GEOGRAPHY AND GEOLOGY OF ALASKA.

the north side of the valley, emphasizes this topographic, feature. The basins are 

from 1 mile to 20 miles in length and 1 mile to 'T miles in width, and probably 

are determined largely by structural" lines in the bed rock.

Near the'one hundred and forty-third meridian the Tok River joins the Tanana 

from the south. This clear-water stream, of no considerable size, has its source 

in the Mentasta Mountains to the south, which do not reach the altitude of 

perpetual snow and hence do not contain any glaciers.

Twenty miles below the Tok there is a telegraph station and small settlement at 

the crossing point of the trail from Valdez on the coast to Eagle on the Yukon. 

This trail traverses the mountains to the south by a broad pass, but 2,800 feet 

above sea level, which probably affords the most feasible railway route from the 

Copper to the upper Yukon.

Two turbulent silt-laden rivers, the Robertson and Johnson, join the Tanana 

from the south, and their unexplored sources lie in the snow-covered Alaska Range 

to the south. Both emerge from the mountains in U-shaped gorges, and the deltas . 

of both are rimmed by bluffs of glacial silts. A, striking feature of both streamsis1 the marked upstream bends which they make at their junction with the Tanana, 

a feature usually interpreted as indicating a reversal of the drainage of the main 

stream. .

, The Gerstle River, a much smaller stream, which, it is reported, enters the 

Tanana from the south, about 10 miles below the Johnson, .is less well known, 

but its valley has probably the same general features as that of the Johnson.

The northern tributaries of the Tanana are all sluggish, flow in broad, shallow 

valleys, and two of them the Goodpaster and the Volkmar are confluent to the 

middle Tanana. It is very unfortunate that local usage among prospectors has 

interchanged the names, of these two rivers. As originally named by Alien* the 

upper of these two rivers should be culled the Goodpaster, and the lower the Volkmar, and this usage was adopted by the writer after his journey of 1898, but the first 

prospectors who ascended the Tanana gave the name Goodpaster to the lower river. 

In spite of the published maps it has been impossible to change this usage, which 

has become fixed since the discovery of gold in this region has attracted a large 

mining population. On the accompanying map (PI. XXXIV) the names have 

been changed to conform to local usage. The Volkmar has not been surveyed, and 

little is known of its course except that its 'headwaters interlock with those of 

Fortymile. The headwaters of the Groodpastcr lie opposite those of Birch Creek; 

its valley is 10 or 11 miles in width in its lower portion, 0 but rapidly narrows 

upstream. Just above the mouth of the Volkmar, at a place called "Masons 

Narrows," the Tanana is much contracted,- being not over 200 or 300 yards in width.

Four or 5 miles below the Goodpaster the Delta River, a rushing, mud-laden 

stream, joins the Tanana from the south. Its delta has pushed the main stream 

against the north wall of the valley, causing a series of small rapids. The Delta d

a Reconnaissance in Tanana and White river basins: Twentieth Ann. Rept. IT. S. Geol. Survey, pt. 7, 1900, pp. 480-481,

6 Alien, H.T.,An expedition to the Copper, Tanana, and Koyukuk rivers in the Territory of Alaska, 1885, Washington, 

1888. See map of Tanana.

"Castner, J. C., Keports of explorations in Alaska: War Dept., Adjutant-General's Office, No. 25, pp. 189-272.

rtMendenhall, W. C,, A reconnaissance from Resurrection Bay to the Tanana River, Alaska: Twentieth Ann. Rept. 

V S Geol Survey, pt 7, 1900, p. 300.
YUKON BASITST. 85

rises within the Copper River Plateau and flows northward for 40 miles in a narrow, 

rock-bound, steep-walled valley through the Alaska Range, whose summits rise 6,000 

to 7,000 feet above the water. Here it is fed by many glacial tributaries. Like the 

other southern tributaries its delta is bounded by glacial silt bluff's 100 to 200 feet in 

height. Below the mouth of the Delta River the south wall of the Tanana Valley 

rapidly recedes from the river and the latter here enters the great lowland which 

extends to the Yukon, 200 miles to the west, This section of the river has been 

called the lower Tanana. The north wall of the valle}T presents a series of salient 

and reentrant angles, which are like those formed by the escarpments bounding the 

the basins of the middle Tanana, and which like them are topographic expressions of 

structural lines. As the lower Tanana follows the north wall of the valley it makes a 

succession of great right-angled bends. Bates Rapids is a term rather loosely 

applied to part of the Tanana stretching about 100 miles below the Delta River, 

where the Tanana flows through numerous channels, separated by sand bars and 

islands, with a current of 5 to 9 miles. At several places it has been crowded 

against the rocky north wall, the moraines of former glaciers, and there are short 

stretches of what might be called rapids.

Twenty miles below the Delta River the width of the Tanana increases to 4 or 

5 miles, then it gradually decreases and is about a half mile wide 60 miles below. 

Here the stream has only one or two channels, with a current of but 2 to 4 miles. 

A few miles from the Yukon the Tanana again broadens and joins the main river 

through several mouths.

The lower Tanana is incised into the plateau to a depth of 1,500 to 2,000 

feet, though the ridges which bound the valley on the north, in the lower 20 

miles, do not reach the plateau level, as they rise only 700 to 1,000 feet above 

the water. The valley floor has a very perceptible slope from the base of the 

highlands on the south to the north wall, and consequently the southern tributaries are swift flowing. The valleys of the northern confluents are broad and 

have low gradients.

The Salcha a River enters the Tanana from the north, and has a broad, flat 

valley, while its headwaters probably lie opposite those of Birch Creek.

Twenty-five miles below the Salcha the valley wall to the north of the Tanana 

is broken by a broad lowland, which probably stretches at least 40 or 50 miles 

to the northeast, and is drained by the Chena River. In its lower portion the 

Chena is tortuous, with a moderate current. It is said to be connected with the 

Salcha by a long slough, which is parallel to the Tanana and a mile or two 

north of it.

Twenty miles west of the mouth of the Chena the Tanana makes a rightangled bend to the southwest, and 40 miles farther downstream is joined by the 

Cantwell from the south. Several small unmapped streams join the Tanana from 

the south between the Delta and Cantwell rivers, and of these the Mahutzu and 

the Silok have their sources in glaciers on the north slope of the Alaska Range.

The Cantwell, a good-sized river, has a glacial source, well within the Alaska 

Range. In latitude 63° 40' it splits into branches of equal size. The eastern

a Spelling in accordance with rules of the United States Board of Geographic Names. In former reports and 

maps usually called the Salchaket, which is also local usage.
86 GEOGRAPHY AND GEOLOGY OF ALASKA.

branch, called Yanert Fork, drains a group of glaciers lying near Mount Haves, 

and follows a U-shaped valley, a mile or two in width, to its junction with the 

other fork, which is regarded as the main Cantwell. This fork rises in a glacier 

near the south slope of the Alaska Range, and is separated from Sushitna waters 

by a broad gap only 2,400 feet above the sea. For 10 miles below the junction 

the Cantwell traverses a minor range in a canyon-like valley, which merges into 

a broader vallej' bounded by gravel terraces, which continues 10 miles more to 

where the river debouches on the Tanana lowland. Here it usually has several 

channels with numerous sand bars. The fall from the forks to the mouth is about 

600 feet, which gives the stream a very steep gradient.

From the Cantwell Delta the Tanana flows northwest for 20 miles to another 

bend, which gives it a westerly course. Here the Tolovana River is confluent 

from the north. Like the Chena River, it drains a broad lowland, a which 

stretches 50 miles or more to the north, and receives many tributaries which 

flow in tortuous courses and with low gradients. Many lakes and small ponds, 

usually surrounded by belts of treeless swamp, are irregularly distributed through 

this lowland. The streams are deep and muddy bottomed. Their surfaces are 

10 to 20 feet below the valley floor at low water in the fall, but during floods 

are nearly flush with it. The banks are usually tirm, and covered with a thick 

growth of birch and cottonwood.

At the boundaries of the lowland the slopes rise gently to the plateau level 

1,500 to 2,000 feet above the floor. This flat, a perfect maze of waterways, is 

almost impassable during the summer except by boat. The natives traverse this 

area in their little birch canoes in summer while hunting and fishing, and in 

winter the frozen waterways afford highways of travel for their dog teams.

The Kantishna, which enters the Tanana from the south about 50 miles below 

the Cantwell is probably 300 yards wide at its mouth, and has only one channel. 

The headwaters of this river drain the north flank of the Alaska Range between 

Mount McKinley and the Cantwell basin. Near latitude 64° 30' the Kantishna 

is split into two streams of nearly equal size, and the eastern one is called the 

Toklat, while the west fork retains the name Kantishna. About 10 miles above 

its mouth the Toklat divides into a number of channels, each of which has its 

source in a glacier on the north slope of the Alaska Range (see PI. XI).

The Kantishna drains Lake Minchumina, 6 an irregular bodj- of water about 

15 miles long by 10 miles wide, which lies close to or at the northern limit of 

glaciation. This is the northernmost lake of any considerable size in the Yukon 

basin. The Kantishna and its tributaries occupy broad, flat valleys, except a few 

of the headwater streams which rise back of the mountain front and have typical 

glaciated valleys. The more northerly drainage channels interlock with those of 

the Fast Fork of the Kuskokwim, from which they are separated by a low 

divide, crossed by a short portage trail long used by the natives. The lower 

Kantishna has not been mapped, but is known to cross the Tanana lowland with 

a fairly steep gradient, and to be separated by low hills from the Cosna River 

Valley to the west.

a Brooks, A. II., An exploration in Mount McKinley region. (In preparation.)

'> Herron, J. S., Explorations in Alaska: War Dept., Adjt. Gen. Office, No. 31, Washington, 1900.
YUKON BASIN. 87

The Cosna," probably 50 miles in length, rises in a highland mass west of 

Kantishna, which may be a remnant of the plateau. The Chitina River, a smaller 

stream, enters at the great double loop of the Tanana known as Harpers Bend.

At the mouth of the Kantishna is another right-angled bend below which the 

Tanana has a northwesterly course for 20 miles. Where it again bends west it is 

joined by Baker Creek.* This large stream forks about 10 miles from the Tanana, 

and the large easterly tributary is called the Hutliua. Both forks How in broad, flat 

valleys near their mouths, but their upper courses have not been surveyed.

It has been shown that the Tanana is formed by the junction of the Chisana and 

the Nabesna, which rise in glaciers in the Wrangell Mountains. The headwaters 

lie in broad basins; the streams traverse the Nutzotin Mountains in narrow valleys, 

and then debouch on the broad lowland in which they combine to form the Tanana. 

The main stream, after leaving this lowland, traverses a series of small connecting 

parallelogram-shaped basins, below which its valley opens out and continues as a 

broad lowland to the junction of the Tanana and the Yukon. The length of the 

Tanana, measured along its longer bends, is nearly 500 miles, that of the Chisana 

is about 100 miles, and that of the Nabesna somewhat more. The tributaries from 

the south rise, for the most part, in the glaciers of the snow-clad Alaska Range, 

and are swift-flowing, turbid streams, while those from the north are of less volume, 

have clear water and sluggish currents.

In 1893 the first steamer ascended the Tanana 'about 100 miles, and in 1898 two 

steamers were successfully taken up to the Chena River, a distance of about 225 

miles. Since 1901 steamers have made frequent trips between the Chena and the 

Yukon, and one at least lias reached the mouth of the Delta River above, but encountered many shoals. With a favorable stage of the water it will probably be possible to 

ascend the river with small powerful boats to the crossing of the Fort3Tinile and 

Copper River trail, for rough determinations made by the writer show that the current 

rarely exceeds 8 miles, and there are only a few short rapids in the entire length of the 

river. At high water a small shallow-draft launch could possibly be taken 150 miles 

above the Fortymile trail crossing to the great bend of the Chisana, but the Nabesna 

is entirely unnavigable. The Chena and the Tolovana are reported deep enough for 

steamers for 100 miles, measuring around the bends of the rivers. The lower 

Kantishna is also navigable for steamers for 100 or 200 miles and the lower Volkmar 

can probably be ascended for short distances.

The Tanana Valley has long been known for its heavy growth of spruce, some 

of which on the lower river attain diameters of 18 inches to 2 feet. Some tamarack 

has been found in the Tanana Valley and the adjacent parts of the Kuskokwim 

Valley, and throughout the lowland areas are extensive meadows of good grass. 

These facts, together with the coal supply found on the Cantwell, make the lower 

Tanana one of the most desirable parts of the Yukon basin for permanent habitation. If the great interior ever attracts an agricultural population it will certainly 

first seek the Tanana Valley. Those who have wintered on the lower Tanana claim 

that the climate is much milder than in adjacent parts of the Yukon basin, but this 

assertion remains to be substantiated by meteorologic records now entirely lacking.

" See Herron's map. ^Called by the natives Sitchlocket.
88 'GEOGBAPHY AND GEOLOGY OF ALASKA.

There are two groups of Tanana natives those of the upper and those of the 

lower valley. Before the coming of the white man these groups were probably 

fairly distinct, for the, river, their natural means of communication, is not easily 

navigated in their frail canoes. The upper river Indians above the range of the 

salmon, which constituted the chief article of food for those of the lower river, were 

dependent on game and small fish. The headwater natives had close communication 

with those of the Copper and Fortyrnile valleys through the low gap in the 

divides which separate these drainage basins, while those of the lower river were 

geographically closely connected with the inhabitants of the upper Kuskokwim 

and lower Yukon.

TOZI EIVER.

The Tozi, a about 100 miles long, flows southwest and has its source near the 

headwaters of several tributaries of the Koyukuk, Ray, and Melozi, which flow into 

the Yukon. Though its valley has not been mapped,- it is known to lie in a region 

of no great relief. 6 The headwaters of the Tozi are connected with those of Kanuti 

River, a tributary of the Koyukuk, by portage trail.

NOTVI EIVEK.

The Nowi, e which enters the Yukon from the southwest, about 75 miles below 

tfie mouth of the Tanana, is about 100 miles a long. It rises on the eastern flank 

of the Kaiyuh Mountains and flows northeasterly. Its headwaters are said to be 

connected by a short portage with the lunoko and also with Kuskokwim waters.

MELOXI RIVEE.

The Melozi e drains a considerable area lying between the Yukon and lower 

Koyukuk. In its upper portion it trends westerly and southwesterly, but within c 

20 miles of the Yukon it flows south and east. According to Lieutenant Alien/ 

the valley of the Melozi, which is about 100 miles in length, is incised into the 

so-called Yukon Hills, whose summits stand 1,000 to 2,000 feet above the sea and 

probably mark the plateau level. Ten miles below the Melozi the Soonkakat, a 

small river which rises near the Koyuk, enters the Yukon from the southwest.

. KOYUKUK BASIN.

The Koyukuk? joins the Yukon from the northwest about 450 miles from 

Bering Sea. Its drainage basin has an area of approximately 25,000 square miles' 

and includes the southern ranges of the Rocky Mountain system which here form 

the Yukon-Arctic watershed. The valley of the Koyukuk, including that of its 

longest fork, is upward of 300 miles in length, while the river measured around 

the bends must be 600 or TOO miles long.

a Generally known as the Tozikakat.

& Alien, H. T., Reconnaissance in Alaska, pp. 94-97.

a Known as the Nowikakat in Alaska. This usage is in accordance with the ill-advised decision of the U, S. Board on 

Geographic Names.

tfDall, W. H., Alaska and its resources, 1870, pp. 87 and 282.

' Generally known as the Melozikakiit.

/See map accompanying Alien's report.

»Schrader, F. C., A reconnaissance along the Chandlar and Koyukuk rivers, Alaska: Twenty-first Ann. Kept. U. S. 

Geol. Survey, pt. 2,1900, pp. 462-471.
YUKON BASIN. 89

Between the Arctic Circle and latitude 66° 30' the trunk stream splits up 

into a number of forks which do not differ greatly in size. Of these the so-called 

Middle Fork, probably the longest, rises north of latitude 68° near the northern 

margin of the range and for 100 miles occupies a mountain valley which is 

sharply trenched to a depth of 2,000 to 3,500 feet below the summits. The 

valley of the North Fork is about 10 miles west of the Middle Fork and 

probably has the same general character. Both forks make southwesterly bends 

before they come together to form the Koyukuk River proper in a lowland which 

stretches southward from the edge of the mountains.

Wild Creek, a large stream with a course in general parallel to the North 

Fork, joins the Koyukuk a few miles below the junction of the two forks. Its 

source has not been surveyed, but probably, like that of the North Fork, it lies 

far within the great mountain mass which lies to the north. Wild Creek flows 

southeasterly in its upper course, but like the other rivers described it makes 

a southwest bend near where it leaves the mountains.

The lower reaches of the North and Middle forks and Wild Creek lie in a 

broad valley basin which is about 20 miles long and 5 miles wide at its upper 

end, but which narrows to 2 miles near the mouth of Wild Creek. Gently sloping 

walls bound the basin, which has a level and silt-covered floor, and at its southern 

end merges into the Koyukuk flats.

Fifteen miles below the junction of the North and Middle forks the John" 

River is confluent from the north. It rises near the northern margin of the 

mountains and traverses nearly the entire rang'e before it enters the plateau 

region. Its headwaters are opposed to those of the Anaktuvuk, which is tributary to the Colville, flowing into the Arctic Ocean. The valley walls of the 

John River rise precipitously, its gradient is steep, and the lower reaches, broad 

and level, merge into the flats of the upper Koyukuk (PI. XXIV, A and B).

A few miles above the mouth of the John River the Koyukuk enters a low, 

silt-covered flat, which is about 4-0 to 50 miles long and 20 to 30 miles wide, 

and slopes gently from north to south. The eastern rim of this flat is outlined 

in part by the South Fork, which joins the Koyukuk from the east, close to the 

Arctic Circle, and heads in the rugged mountains north of the sixty-seventh 

parallel of latitude. It flows in general southwesterly, parallel to the Middle Fork 

and to the upper Koyukuk, and traverses the eastern margin of the Koyukuk 

Flats, bends sharply to the west, and joins the Koyukuk after traversing the 

lowlands.

Within the lowland the Fickett River joins the Koyukuk from the north, 

heading well within the mountains to the north. Though its course has not been 

mapped, it is known that a broad valley extends for 10 to 20 miles up from its 

mouth. At the mouth of the South Fork the Koyukuk makes a westerly bend 

and thence flows in a tortuous course across the lowland for about 50 miles 

to the Alatna River, where it turns to the southwest, and 10 miles farther down 

enters an upland region. The Koyukuk Flats have been outlined only in part 

by surveys, but are known to comprise a large level basin which has an altitude

"Schrader, F. ., Reconnaissance in northern Alaska: Prof. Paper I'. S. Geol. Survey No. 20.
90 GEOGKAPHY AND GEOLOGY OP ALASKA.

of about 600 feet, and above which the highland rises 2,000 to 3,000 feet by 

gentle slopes.

c,The lowland floor is extended northward for 20 to 30 miles by the broad, 

flat valley of the Alatna" River, which upstream gradually narrows and becomes 

steeper walled, but continues to be flat and is traversed by the river in many 

meanders. The source of the Alatua lies in an unexplored part of the Endicott 

Mountains. A portage trail connects the Alatna with Kobuk waters near the 

sixty-seventh parallel of latitude. Below the mouth of the Alatna the Kcr^ukuk 

flows southwesterly, with many minor bends, for 100 miles. Along this portion of 

the river the valley is from 1 to 2 miles wide, and the walls rise rather abruptly to 

an upland which stands between 1,500 to 2,000 feet above the river.

A few miles below the flats the Kanuti River is tributary from the southeast. 

Its source" lies in a mountain mass 2,000 to 3,000 feet in height, which is drained in 

part by the Dall River, a tributary of the Yukon. The following is from Mendenhall's 6 description:

"The Kanuti River is approximately 200 miles long, and within that distance its 

valley presents great physical diversity. It heads in the same mountains whose 

northern slopes are drained by Fish Creek and Jim River, but within a fe\y miles of 

its source it enters a relatively flat basin, 9 or 10 miles long and half as wide, which 

contains a number of small lakes and ponds, although standing at an elevation of 

between 1,200 and 1,400 feet. This basin, like all similar topographic features in the 

north, whatever their relation to sea level, is a marsh covered with the usual tundra 

growth. At its lower end, in longitude 150° 45' west, the river enters a restricted 

valley, so steep walled in places as to deserve to be called a canyon and having a 

maximum depth of 2,000 feet. The gorge-like character prevails for about 30 miles, 

and through this portion the river can scarcely be called navigable, since it is a 

succession of rapids, and the river channel throughout is obstructed by bowlders of 

all sizes. Below this stretch the valley gradually broadens, and near the camp of 

July 12 is an extensive flat, which is perhaps a part of the broad basin in which the 

lower portion of the South Fork of the Koyukuk flows.

" Within this lower basin the Kanuti River receives a large tributary from the 

south in the direction of the sources of the Tozi and Melozi, and 25 miles above 

its mouth the river plunges into a second canyon about 10 miles long and 500 feet 

in depth. This is the most beautiful section of the river; the stream is swift, but 

free from dangerous rapids, and the bluffs of slate and sandstone rise sheer from the 

water to a height of several hundred feet. Ten miles above the mouth it receives the 

waters of the Mentanontli, descended by Lieutenant Alien in 18S5-after his overland 

journey from the Yukon.

"The hills which border this lower section of the Kanuti River and adjacent 

parts of the Koyukuk are seldom more than 1,500 feet in height, are not excessively 

steep, and are well timbered."

Near latitude 65° 40' the Koyukuk Valley makes a northwest bend, and 50 miles

oMendenhall, W, C,, Reconnaissance from Fort Hamlin to Kotzebue Sound: Prof. Paper U. S. Geol. Survey No. 10, 

1902, p. 24.

b Ibid., pp, 22 and 23.
YUKON BASIN. 91

below swings to the southwest and the valley opens out. From this point to the 

Yukon the gradient is low and the river is tortuous, with numerous channels.

Below the Kanuti the Koyukuk receives a number of important tributaries 

but few have been mapped in any detail. The Hogatxa River interlocks its headwater drainage with southern tributaries of the Kobuk. and the two drainage systems are said to be connected by easy portage. The other tributaries of the 

lower Koyukuk now from the west and arc smaller than those described.

Tn ordinary stages of water steamers ascend the Koyukuk 440 miles, to the 

trading post of Bergman, the current averaging probably 4 miles an hour, and 

at high water steamers can be taken 100 miles farther upstream. The upper 

Koyukuk and most of its tributaries are navigable for small boats only, and often 

not even for those, except in their lower courses.

The natives make use of the river in their journeys, and have communication 

with the middle Yukon by the portages to Dall, Chandlar, and Melozi rivers. 

The passes into the Kobuk and the rivers flowing northward were probably little 

used, as the natives in the Arctic watershed are Eskimo, and previous to the 

coming of the white men their intercourse with the Indians of the Yukon waters 

was anything- but friendly.

KALTA<; UIVEH,

The Kaltag, a small river, enters the Yukon from the northwest, 60 miles 

below the mouth of the Koyukuk. It rises not far from Unalaklik waters and 

flows through a broad valley. The two valleys offer winter routes of travel from 

the Yukon to Norton Sound and are followed by the military telegraph.

KAIYUH RIVKK.

The Kaiyuh River, the next considerable tributary to the Yukon below the 

Koyukuk, has its source in the mountains of the same name. As far as known, 

it flows southwesterly and has a length of probably 60 miles.

INNOKO KIVEK.

Halfway between the Bering Sea and the mouth of the Koyukuk, in latitude 

63% the Innoko River joins the Yukon from the cast, but a part of its drainage 

is carried by the Shageluk Slough, which enters the Yukon 60 miles farther downstream. The source of the Tnnoko is on the east flank of the Kaiyuh Mountains, 

about 30 miles to the east of the Yukon. The lower valley of the Innoko was 

visited by the Russian Lieutenant Zagoskin« in 1844, and the present mapping of 

the river is largely based on his notes. The Innoko is believed to occupy a broad 

valley which, for 150 miles, is parallel to the Kaiyuh Mountains.

ANVIK JUVEK.

The Anvik River, probably not over 100 miles in length, drains the neck of 

land lying between the lower Yukon and Norton Sound. Its headwaters lie in a 

highland mass 2,000 to 2,500 feet high and only about 20 miles from salt water. 

The streams whose junction forms the Anvik flow easterly, but the Anvik has a 

southerly course parallel to the Yukon.

i Zagoskin'B Reiso jm Russischen Ainerika: Erman's Archiv fur Wissensohaftlichen Kunde, vol. 7, 1849, pp. 432-440.
92 . GEOGKAPHY AND GEOLOGY OF ALASKA.

No streams of importance join the Yukon between the mouth of the Anvik 'and 

the delta, which has already been described as a maze of intricate waterways (see 

p. 79).

SUM3IARY.

The Yukon, the largest river of Alaska, has its source in two rivers, which rise 

in northern British Columbia and have northwesterly courses. The Yukon flows 

northwest as far as the Arctic Circle, where it swings to the southwest, parallel to 

the crescent-like bend made by the two dominant mountain systems and "to the great 

reentrant angle in the southern coast line. The Yukon Valley is narrow and steep 

sided to where it meets the Yukon Flats, a great lowland area in which the river 

spreads out into numerous channels. Below the flats the valley is again constricted 

for a distance of 200 miles in the Rampart region, but from the Tanana to the sea it 

broadens out and near the delta finally gives way to the coastal tundra belt.

The Yukon Valley and much the, greater part of its basin lie in the Central 

Plateau region, while its larger southerly and easterly tributaries, such as the Lewes, 

White, and Tanana, drain a part of the inland ranges of the Pacific Mountain system, 

and the headwaters of the easterly and northerly tributaries, such as the Pelly, 

Stewart, Porcupine, and Koynkuk, receive waters from the southern and western 

slopes of the Rocl\y Mountains. The Yukon is fifth in size among North American 

rivers. It is navigable from its head, at the junction of the Lewes and Pelly, to its 

mouth,.a distance of probably 1,800 miles1. Steamers have been run on nearly all its 

larger tributaries, and the navigable waters in the entire basin probably aggregate 

over 3,500 miles, about three-fourths of which are in Alaska.

NORTON SOUND.

Between the coast line east and north of the Yukon Delta and the southern 

shore of the Seward Peninsula are the shallow bodies of water known as Norton 

Sound and Norton Bay. The streams flowing into these waters are mostly short, 

and near their mouths meander sluggishly over the plain, which nearly everywhere 

stretches inland from tide water. Among the largest of these streams is the 

Unalaklik River/' tributary to Norton Sound, whose source lies in a group of 

hills forming the Yukon divide. This river flows in a general westerly course, 

and its entire length is probably not over 50 miles. It can be ascended in small 

boats,- and a portage trail of 30 miles connects the head of boat navigation with 

the Yukon River at the mouth of the Kaltag River. Fifty miles to the north 

is -the Shaktolik River, a smaller stream, whose headwaters probably do not 

reach beyond the coastal plain. The unsurveyed Ungalik and Inglutalik rivers 

are probably larger and are also tributary to Norton Bay from the east.

SEWARD PENINSULA.*

The Bering-Arctic watershed follows a sinuous line along the longer axis of 

the peninsula to. Cape Prince of Wales, and sends the waters of over two-thirds

'n'Allen, H. T., Reconnaissance in Alaska, pp. 109-113 and map 5.

. - b Brooks, A..H., A reconnaissance of the Cape Nome and Norton Bay regions: U. S. Geol. Survey, 1901, pp. S3-55. 

Mendenhall, W. 0., A reconnaissance in the Norton Bay regions: U. S/Geol. Survey, 1901, pp. 195-198. 

Collier, A. J., A reconnaissance .in ^he Northwestern part of the Seward Peninsula: Prof. Paper U. S. Qeol. Survey 

No. 2,1902, pp. 13 and -12.

Moflitf F. H.,The Pairhaven gold placers of the Seward Peninsula: Bull. U. S. Geol. Survey No. 248.
U. 6. GEOLOGICAL 8URVEV PROFESSIONAL PAPER NO. 45 PL. XVII

A. VALLEY OF FOX RIVER, SEWARD PENINSULA.

JB. VALLEY OF FORTYMILE RIVER NEAR THE BOUNDARY.
SEWAED PENINSULA DRAINAGE. 93

of its area southward to the Bering Sea. The highlands consist of rolling upland 

1,000 to 2,500 feet above the sea (PL XIII), and there are some isolated mountain 

masses which stand higher, but the latter in no case determine the east and west 

divide. The headwaters of the streams flowing into the Arctic and Bering seas 

interlock irregularly within the upland, throwing the watershed first north, then 

south, and giving it the irregularity which has been described. The Kxryuk River, 

one of the largest of the peninsula, enters a small tidal estuary at the head of Norton 

Bay. Its source is in a gravel-floored basin, which lies well toward the center of 

the peninsula and is bounded on the south by the Bondeleben Mountains, which rise 

2,000 feet, and by highlands on the north, rising 1,500 feet above its floor. The 

Koyuk flows in a tortuous course and with sluggish current across this basin, 

which it leaves through a narrow valley with a steep gradient. This canyon-valley 

type continues eastward for about 20 miles, to where the river enters another broad, 

level-floored valley which extends oast and south, gradually opening out and merging 

into the coastal plain of Norton Bay.

The Kwik Ri\rer enters Norton Bay 20 miles west of the Koyuk. It flows southward through a broad and almost featureless depression which northward is connected 

with the Koyuk basin by a low pass.

Eight miles west of the Kwik is a lagoon into which flows the Tubutulik 

River. This stream rises in a group of low mountains 30 miles from the sea, 

traverses a small basin, then takes a tortuous course through the hills and enters 

the coastal plain 10 miles from the sea. The Kwiniuk River, which empties into 

the same lagoon, rises in low hills 10 miles from the coast and flows in a broad 

valley from which it emerges on the coastal plain.

At Cape Darby the shore line suddenly retreats inland, and to the northwest 

are Golofnin Bay and Golofnin Sound. At the head of the sound is the broad 

delta of Fish River, and the valley of the latter stretches northward for 10 miles 

as a broad depression, then contracts for a few miles only to open again to a second extensive lowland, which also includes the lower reaches of the Niukluk 

River, the principal tributary of the Fish. The Fish rises in a basin which is 

typical of the basins at the headwaters of many rivers of northern Alaska 

(fig. 5). These basins are level, gravel-filled depressions encircled by uplands 

whose slopes often rise abruptly. Within them the streams have low grades and 

flow with tortuous courses, but below them flow through narrow canyon-like 

often rockbound valleys, with straight courses, steep gradients, and frequent 

rapids. The basin of the Fish is of rectangular outline, 30 miles long and 20 miles 

wide, and below it is a constricted valley which is about ]0 miles long, less than a 

mile in width, and has abrupt walls. Within the basin the river is tortuous and has 

a sluggish current, while in the canyon it is comparatively straight and descends 

through a series of rapids.

Niukluk River, the largest confluent stream, joins Fish River about 20 miles 

from the sea. Near the mouth its valley has a width of about 6 miles, which 

gradually decreases to less than a mile near Richter Creek, while 8 miles above the 

stream flows for 2 miles through a steep-walled rock-bound canyon 50 feet 

deep. Above the mouth of the Casadepaga the valley broadens out to a basin 

(PI. XXXIII, A) separated by only a very low divide from the Kruzgamepa, 

17211 No. -15 06 7
94 GEOGRAPHY AND GEOLOGY OF ALASKA.

which flows into Port Clarence. The two basins connected by a sharply incised 

valley are striking features. The valley of Casadepaga River, the chief tributary 

of the Niukluk, is broad, with gentle slopes, broken by gravel terraces up to an 

altitude of 600 feet. The headwaters of the Casadepaga are connected bv a low, 

gravel-filled divide with Solomon River, which flows southward.

West of Golofnin Bay the Solomon and Eldorado rivers, as well as many 

smaller streams, carry the drainage southward through broad open valleys, 

whose slopes are often terraced. The Eldorado and Nome rivers rise in gravelfilled basins of the type already described, which to the north are connected by 

broad passes 'with Kruzgamepa waters, and to the south are succeeded in turn 

by a constricted valley and a broad valley whose floor merges into the coastal 

plain. The Snake, Penny, and Cripple river valleys merit no special description. 

Near the coast they are broad, and their floors are extensions of the coastal plain, 

above which they become constricted.

Sinuk River," which empties into the sea about 30 miles west of Nome, is one 

of the largest rivers of the southern watershed of the Seward Peninsula, and 

receives the drainage from the southern slope of the Kigluaik Mountains. It 

emerges from the mountains in a narrow gorge and flows in a broad depression 

parallel to the range for about 15 miles, turns southward and reaches the sea 

through a broad flat valley. Its waters, as well as the headwaters of its chief 

tributary, Stewart River, are connected by a broad, gravel-filled pass with the 

Kruzgamepa Valley.

Fairview and Feather rivers are streams of minor importance which flow 

westward from the southern flanks of the Kigluaik Mountains. Tisuk Creek is 

somewhat larger and drains the northern slopes of the Kigluaik Mountains, from 

which it emerges in a narrow valley which broadens out. In its lower course 

the current meanders sluggishly over a flat valley floor and finally empties into a 

lagoon of Bering Sea. A gravel-filled divide about 200 feet high separates the 

Tisuk from Canyon Creek, which flows northeastward into Imuruk Basin.

A number of small streams flow into Port Clarence and Grantley Harbor 

from both the north and the south, but the Bluestone River drains the larger 

part of the area lying between the Kigluaik Mountains and Port Clarence. Its 

headwaters are in a basin-shaped valley, but at the mouth of the Alder it enters 

a rock-cut canyon, below which it flows through a broad valley tributary to the 

Tuksuk Channel.

The head of Imuruk Basin is bounded by a flat, swampy area, through which 

meanders a broad river, sometimes called the Kaviruk, which forks about 20 miles 

from the bay. The southern fork, called the Kruzgamepa, rises well within the 

Kigluaik Mountains, flowing southward till it leaves them, then takes a northeasterlv 

course and encircles the east end of the range. This part of the valley lies in the 

same lowland that includes the upper basin of the Niukluk. The northern fork of 

the Kaviruk, called the Kuzitrin, has its source in a broad, flat basin in which it is 

joined by its chief tributary, the Kougarok. Below the basin it flows through a rather 

narrow valley for about 20 miles, and debouches on the plain at the head of Imuruk

a Locally often called the Sinrock River.
ARCTIC DRAINAGE. 95

Basin. A third large area is drained into Imuruk Basin from the north by the 

Agiapuk River.

Between Port Clarence and York are several streams which have in general a 

.southerly course, but which are insignificant in size. West of Cape York the first 

important river is the Kanauguk, which lies well within the York Mountains.

The Arctic drainage of the Seward Peninsula, embracing probably not over a 

third of its area, is all of practically the same general type. The headwater valleys 

are broad and open, and the watersheds separating them from the valleys of the 

streams flowing south are often very low. The passes are broad and gravel-filled, 

and suggest recent changes in drainage. The valle3rs of the northward-flowing 

streams open out as they approach the Arctic, the gradients become less, and 

finally the floors merge into the coastal areas, through which the streams meander 

with sluggish currents. Many of the Arctic streams empty into large lagoons, 

which are cut off from the ocean by long barrier beaches. The streams on the 

Arctic coast are straighter than those flowing into Bering Sea. The easterly streams 

flow northeast, the westerly ones northwest. West of Cape Espenberg the 

Serpentine, Arctic, Kougarok, Pinguk, and Mint are the chief rivers, while the 

Goodhope, Cripple, Inniachuk, Kugruk, Kiwalik, and Buckland drain the 

northeastern part of the Peninsula.

The Buckland River, which flows into Eschscholtz Bay, a part of Kotzebue 

Sound, through a long tidal estuary, rises about 75 miles southeast of the ba3T , and 

opposes the drainage flowing on one hand into Norton Bay and on the other into the 

lower Koyukuk. The lower 60 miles of this river were explored in 1849" by 

expeditions sent out from II. M. S. Herald, and Plover. The reports of these 

parties show that dead water extends for about 30 miles from the mouth, and that 

there are no serious rapids for 30 miles farther upstream. There is a native 

settlement near the head of the river which is connected by portage trail with the 

Kateel River, a tributary of the Koyukuk.

ARCTIC DRAINAGE. 

OUTLINE.

Though the Arctic coast has been explored and roughly charted for upward of 

half a century, there are still large tributary areas practically unknown. The 

relief and drainage indicated on the accompanying map (PI. XXXIV) are based on 

observations made from the coast and on the results of the few exploring 

expeditions which have penetrated inland, and will, therefore, require much 

revision after more extended and sj'stematic surveys are executed.

The streams tributary to the Arctic Ocean drain less than one-third of Alaska 

and fall into two groups: First, those flowing westerly into Kotzebue Sound, and, 

second, those having northerly courses and emptying1 directly into the Arctic 

Ocean. The drainage of the northern half of the Soward Peninsula, which might 

property fall into the second division, has already been considered.

nJIendenhall, W. C., Prof. Paper U. 8. Qeol. Surrey No. 10, 1902, p. 12.
96 GEOGRAPHY AND GEOLOGY OF ALASKA.

HOTHAM INLET DRAINAGE.

The eastern coast of Kotzebue Sound is broken by many deep embayments 

and inlets. The largest of these Hotham Inlet is a long, irregular-shaped body 

of water, cut off from the sound by a long, narrow neck of land. The largest 

tributaries of Kotzebue Sound the Noatak, the Kobuk, and the Sclawik flow into 

the inlet. The drainage basins of the first two are probably entirely within the 

ranges which make up the Rocky Mountain system in this part of Alaska, while the 

valley of the Selawik probably marks the southern margin of the system.

The Selawik, the southernmost of the three, empties into Selawik Lake, which is 

connected by a narrow water passage with the head of Hotham Inlet. This lake or 

lagoon undoubtedly owes its origin to the building out of the delta of the Kobuk 

River, which has thus cut off a part of the former extension of the inlet. Several 

smaller bodies of water to the east are connected by tidal" channels with the larger 

basin.

A broad delta marks the mouth of the Selawik 6 River, whose various channels 

connect with the above-described lagoons. The Selawik rises on the north slope of 

a group of mountains 3,000 to 4,000 feet high, whose southern slopes drain into the 

Koyukuk. The upper valley is probably rather narrow, but for 60 miles above its 

mouth the river meanders across a broad, level-floored valley. On the north the 

Waring Mountains, which are from 2,000 to 2,500 feet high, separate the Selawik 

from the Kobuk drainage, while to the south the highlands are probably of less 

altitude. Several good-sized tributaries join the lower course of the Selawik. Of 

these the Kugerack from the north is separated by a very low divide from waters 

flowing into the Kobuk.

According to Stoney 6' 16 feet of water can be carried over the bar of the deepest 

of three outlets of Lake Selawik, and he reports also 6 feet of water in the river as 

far as the " forks," d to which point the current is less than 3 mites per hour.

The eastern shore of Hotham Inlet is formed by the broad delta of the Kobuk e 

River, whose headwaters have not been explored, but are known to lie about 200 

miles due east of Hotham Inlet, in a high mountain mass near latitude 67°, longitude 155°. In the same region are probably the sources of the Alatna, which flows 

south into the Koyukuk; of the Noatak, which flows west into Kotzebue Sound, 

and of a branch of the Colville, which flows northerly into the Arctic Ocean. The 

general trend of the valley of the Kobuk is east and west with, however, a number 

of broad bends. The lower half of the valley is characterized by a broad, flat 

depression, while the upper half, made up of a series of basins and connecting 

canyons, is of the general type already described (pp 281-283).

The Kobuk is between 400 and 450 miles long and receives many tributaries 

all the larger ones from the north. Its basin has an area of probably 8,000 to 9,000 

square miles, and is incised into a mountainous belt made up of several ranges 

which have altitudes of from 2,000 to 4,000 feet, and which are believed to be the

a Cantwell, J. C., Exploration of the Kowak Elver, Alaska: Cruise of the Corwiu in the Arctic, 1884, p. 68. 

&Geo. M. Stoney, Lieut. U. S. N., Naval explorations in Alaska: U. S. Naval Institute, pp. 41 and 54. 

clbid., p. 65.

<l Stoney probably refers to the mouth of the Kugerack, which is the largest tributary of the Selawik. 

eTlie description of Kobuk basin is largely taken from a " Reconnaissance from Fort Hamlin to Kotzebue Sound," by 

W. C. Mendeuhall: Prof. Paper U. S. Geol. Survey No. 10, 1902.
ABCTIC DRAINAGE. 97

western extension of the Rocky Mountain system. Of the numerous lakes in the 

upper valley, Walker Lake, the largest, 14 miles long by 2 miles wide, is known to 

be of glacial origin. The walls surrounding it rise to altitudes of 3,000 or 4,000 

feet. The Kobuk flows through Walker Lake and below the outlet receives the 

Kichaiak, a small creek from the east. This stream heads in a pass opposite 

Help-me-Jack Creek, a tributary of the Alatna River, and is used as a summer route 

between the Kobuk and Koyuknk waters. It was first explored in 1901 by the 

Mendenhall party.

Above the lake the Kobuk flows southeasterly through a comparatively narrow 

valley, while below the valley broadens out to 4 or 5 miles and the river swings to 

the southwest. In this upper course it receives the drainage of Nutuvukti Lake, 

which lies a few miles to tho northwest, and is separated by a broad flat divide less 

than 200 feet high from Reed River, another northwesterly tributary of the Kobuk.

Twenty miles below Walker Lake the Kobuk Valley swings to the southwest, 

and at the so-called "Gorge'' (PI. XXXIII, j?) contracts to a mile or less in width, 

then takes a westerly course and opens out to 8 or 10 miles. Reed River enters 

from the north, not far below the gorge, and is said to be connected by winter trail 

with upper Noatak. Beaver Creek, which joins the Kobuk a few miles below, is 

the outlet of a small lake lying 25 miles north of the main river.

Near the one hundred and fifty-sixth meridian the Pah River enters the Kobuk 

from the south. Its headwaters lie opposite the headwaters of the Dakli River, 

which flows southward into the Koyukuk. A low depression between the two 

streams Zane Pass affords an easy route between the two basins. A few miles 

above the Pah is a small tributary from the north, which drains Lake Selby, 8 

situated just at the northern margin of the vallej^. The Maunehik River, confluent 

20 miles below, drains two small lakes 10 and 35 miles to the north. The next river 

of importance, going downstream, is the Kogoluktuk, which flows from the north. 

Its headwaters are said to be connected by a low pass with the streams flowing 

northward into the Noatak.

In the 50 miles below the mouth of the Kogoluktuk the Kobuk receives several minor tributaries from both sides and the Ambler the largest tributary which 

is confluent from the north near the one hundred and fifty-eighth meridian. The 

Ambler rises within 15 miles of the Noatak,* and is one of the chief routes of 

communication for the natives between the two basins. In its upper course the 

Ambler flows southwest probably in a narrow valley to within 25 miles of the 

Kobuk, where it bends westerly and traverses a broad flat valley, which continues 

to its mouth, and in which it receives its one important tributary, the Redstone 

River.

From the gorge to about the one hundred and sixtieth meridian the Kobuk 

Valley is a broad depression, in which the river has a tortuous course. Near the 

meridian mentioned the valley suddenly contracts to a width of about 2 miles, 

and then the walls again recede and the valley merges into the plain of the delta. 

The Squirrel River, tributary from the north near the head of the delta, rises in 

the Baird Mountains the watershed between the Kobuk and the Noatak.

<*Naval Explorations in Alaska (map). ft Naval Explorations in Alaska, pp. 37 and 38.
98 GEOGKAPHY AND GEOLOGY OF ALASKA.

Near the one hundred and sixty-first meridian the north wall of the valley 

recedes and swings around the head of the eastern arm of Hotham Inlet, while 

the mountain range which forms the south wall terminates abruptly at the delta, a 

featureless plain, across which the river sends its drainage to the inlet through innumerable tortuous channels. The delta is about 30 miles square, and is bounded on 

the south by Selawik Lake and on the west and north by Hotham Inlet. It is 

traversed by a maze of intricate waterways, with numerous lakes and lagoons, is 

being rapidly extended seaward, and is constantly encroaching on the shallow 

waters of Hotham Inlet.

The Kobuk is navigable for river steamer 4 as far as Camp Eiley, 225 miles 

from the mouth, and small launches have been run above this point. Cantwell 

and Stoney, ffi who explored the Kobuk in 1884 and 1885, made use of launches 

and steamers on the lower 200 miles of the river, but for many years after no 

attempt was made at steam navigation. In 1898 upward of 1,500 gold seekers 

made their way to Kotzebue Sound and many ascended the Kobuk, using several 

steamers and launches, and encountering no serious difficulties below Camp Riley.

Stoney 6 reports that the entrance to the deepest channel in the delta is off 

Nimiuk sand spit, and that there are two fathoms of water over the bar, while 

Mendenhall c states that the deepest channel begins near the passage to Selawik 

Lake. The exploration of the Mendenhall party proved that although the upper 

river contains several rapids it is navigable, at least as far as Walker Lake, for 

canoes handled by experienced men. The descent of the lower 200 miles of the 

Kobuk is only 200 feet, and the current is moderate. Walker Lake, about 400 

miles from the inlet, stands about 400 feet above tide.

The Noatak is the third and probably the largest of the three rivers which 

flow into Kotzebue Sound from the east. Its head lies near the sources of the 

Colville and Kobuk, and its general course is westerly until it approaches within 

30 miles of the coast, where it bends sharply and reaches the sea at the north 

end of Hotham Inlet by a general southerly course. So far as known the 

valley of the Noatak consists of a number of broad flat basins connected by 

neck-like canyons.

There are no accurate maps of the Noatak, and explorations have been 

carried over only a part of its basin. The following statements are based on 

reports by McLenegan d who ascended the river to about the one hundred and 

fifty-seventh meridian in 1885, and by Stoney" and Howard/ who explored a 

part of its headwaters in 1885 and 1886.

The source of the Noatak is in a mountain mass which also gives rise to the 

Kobuk and Alatna rivers on the south and to branches of the Colville on the 

north. Its upper course is northwest in probably a rather narrow valley, where 

it gradually swings to the west, and near the one hundred and fifty-sixth 

meridian opens into a broad basin, across which the river makes tortuous meana Naval Explorations in Alaska, pp. 37 and 38. 

Ubid., p. 49. 

"Ibid., p. 27.

d McLenegan, S. B., Explorations of the Noatak River, Alaska: Report of the Cruise of the Revenue Steamer 

Conoin in the Arctic Ocean, 1885, Washington, 1887, pp. 53-80.

eStoney, Geo. M., Naval explorations in Alaska: Naval Institute, 1900, pp. 37-40 and 54-55 and 66-68. 

f Howard, Lieut. W. L., was a member of Stoney's party.
ARCTIC DRAINAGE. 99

ders. Broad low passes separate this part of the valley from Colville waters on 

the north and Kobuk waters on the south. Below this upper basin the valley 

contracts somewhat and then in a few miles again broadens into a basin, probably 

10 to 20 miles in width, and receives a tributary from the south called by Stoney 

"Caribou River" (Cutler River). Through this lowland the river flows westerly 

to about the one hundred and fifty-ninth meridian, where it bends south and flows 

through a canyon 4 or 5 miles in length, below which the valley broadens again, 

and about 20 miles farther downstream the river enters another broad basin, 

through which it takes a westerly course. Forty miles below the valley again 

contracts and the river, bending to the southwest, enters the so-called Grand Canyon, which is 6 to 8 miles long. Below the canyon both valley walls rapidly 

recede, encompassing a lowland which is 20 miles in width and is sparsely timbered 

with spruce and within which the river swings from the southwest to south. 

Where the river leaves this lowland it flows almost due east; it bends to the 

south and traverses the western extension of the Baird Mountains in a series of 

long, sweeping curves. The valley is here only about 2 miles in width, with one 

rock-walled canyon 2 miles in length. A short distance below the canyon the 

river emerges on the coastal plain, and then, after making a double bend to the 

east and south, reaches the delta, where it is diverted into three or four main 

channels, through which it finds its vfay to the sea. The delta of the Noatak forms 

the northern shore of the Hotham Inlet and appears to be of much less extent 

than that of the Kobuk.

The four gravel-floored basins and the connecting canyons described above 

are striking topographic features of the Noatak Valley and resemble similar forms 

in the Kobuk Valley, as well as in some of the valleys of the Seward Peninsula 

(pp. 93-95). In the basins the valley slopes are gentle, and the Noatak River 

meanders over the gravel floor in one or more channels, while in the canyons the 

walls rise abruptly and the river has usually but one channel.

The Baird Mountains, a well-defined range south of the Noatak, extend east 

and west and form the watershed between the drainage basins of the Noatak 

and the Kobuk rivers. They reach altitudes of 3,000 to 4,000 feet, and are said 

to fall off to the Noatak Valley gradually through a series of foothills. The slope 

to the north from the Noatak Valley is also gradual to the so-called De Long 

Mountains, which are somewhat less well defined and probably lower than the 

Baird Mountains. Both ranges are included in the Rocky Mountain system.

The height of the walls of the Noatak Valley has not been determined, but 

it is probably not over 2,000 or 3,000 feet. As far as known, the Noatak receives 

no large tributaries. The current of the stream is reported to be swift, and in 

the basins the river is split up into many shallow channels, so it is very doubtful 

whether steamboat navigation would be feasible, it is reported that there are 6 

feet of water in the delta, but above, according to McLenegan's soundings, the 

river rapidly shoals to li and 2 feet. The Noatak Valley lies just north of the 

limit of timber, but spruce grows sparsely in its lower 100 miles, and cottonwood is 

found for some distance above, while willow alone is found in its upper valley 

(PI. XII).
100 GEOGRAPHY AND GEOLOGY OF ALASKA.

The natives travel along the entire length of the Noatak, but their more 

permanent habitations are among its headwaters, from which they have communication with the Kobuk on the south and the Colville on the north. Along the 

latter stream and the Chipp River they make annual excursions to the north 

Arctic coast for purposes of hunting and fishing.

KOTZEBUE SOUND TO POINT BARROW.

From Kotzebue Sound the Arctic coast line extends northwest as far as Cape 

Hope, then bends to the north and finally to the northeast as far as Point Barrow. 

The rivers which enter the Arctic along this stretch of coast are, for the most 

part, unmapped and unexplored.

Seventy-five miles northwest of Hotham Inlet the Kivalina and Wulik flow 

into a large lagoon. These two rivers head near the great southerly bend of the 

Noatak and flow nearly west. a

The Kukpuk River enters the Arctic Ocean at Point Hope, ^n its lower 

reaches it is bordered by a broad valley, which is cut in a highland mass 1,000 to 

1,500 feet in altitude, and*which has a general east-west trend. It flows across a 

broad delta into Marryatt Inlet, a tidal lagoon. The barren beach of this lagoon, 

modified by wave and current action, forms the long sand spit called Point Hope. 

The Pitmegea River, which enters the ocean at the bight in the coast line east of 

Cape Lisburne, has a northwesterly course, and its valley is incised in the uplands 

which are not over 1,000 to 2,000 feet high. The four rivers described lie entirely 

within the highland region, which is regarded as the western extension of the 

Anaktuvuk Plateau of the Arctic Slope region.

The highlands which northward from Kotzebue Sound rise either directly from 

the sea or from a narrow coastal plain trend inland northeast of the Pitmegea 

River and give way to a low tundra, across which streams meander sluggishly, 

without any well-defined valleys, and which is dotted with lakes and extensive 

marshes. The lack of relief makes changes of drainage very common, and these are 

probably often brought about by ice barriers. The Kupowra and several smaller 

rivers which enter a lagoon about 40 miles northeast of the Pitmegea rise in the 

highland region to the south, but in their lower course meander over the coastal 

plain. The Utukok reaches the sea 100 miles to the northeast and the Kuk at 

Wainwright Inlet, a small tidal estuary near Cape Collie.

NORTH ARCTIC DRAINAGE.

East of Point Barrow the Arctic slope is drained by three main rivers, the 

Meade, Chipp, and Colville, and many smaller unexplored and unnamed streams 

all having northerly courses, which in their lower reaches flow across the tundra 

in tortuous channels.

The Meade River probably has its source in highlands, near latitude 69° and 

longitude 157°. Its lower valley was explored by Ray, * who, in 1883, during a

« The positions of the valleys of these rivers is strongly suggestive of the idea that one or the other may have been the 

former outlet of the Noatak. There is, however, no topographic evidence avallabe to prove or disprove such a 

hypothesis.

&Ray, P. H., Expedition to Point Barrow, Alaska: 48th Cong., 2d scss., Ex. Doc. No. 44, pp. 26-28.
ARCTIC DRAINAGE. 101

winter overland journey from Point Barrow, asceoded it from latitude 70° 30' to 

about latitude 70°. Where he first saw the river he describes its valley as shallow, 

winding, and incised to a depth of 100 feet in sands and gravels. Upstream, to the 

south, the valley continues its tortuous course, but the relief near the highest point 

reached by Ray had increased to about 200 feet, and Ray states that the source of 

the river lies in a low range of mountains, probably the western extension of 

Anaktuvuk Plateau. The Inaru, a small river, drains some small lakes which lie 

about 40 miles southwest of Point Barrow and empties into Dease Bay. It flows 

parallel to the lower Meade.

The Chipp ffi River has two outlets, one into the head of Dease Inlet, where it is 

joined by the Meade River, and another 40 miles to the east in Smith Bay. 

Its basin is ill denned and is cut up by a maze of waterways. The source of the 

Chipp, near latitude 68° 30', lies in a rolling upland region probably the 

piedmont plateau (Anaktuvuk) already described. The river follows a very devious 

course, but its general direction is northerly. Forty miles from salt water it 

receives one important tributary 6 from the southwest. Howard states that at the 

head of the Chipp the hills are 500 feet above the valley bottom. Near the 

seventieth parallel of latitude the river emerges from the uplands and enters the 

low coastal plain, and here Howard determined its width to be 400 yards and 

depth 14 feet, but these measurements were made nearly at high water in the 

spring.

The Chipp is navigable for steamers for a long distance, but as it is locked 

in the ice all but about two months in the year and as its basin yields nothing 

of value, this fact is of no commercial importance. Willows 12 feet high are 

found along its headwaters, but its lower course is entirely destitute of timber 

A portage trail through a low divide is used by the natives in traveling from 

the Colville to Chipp waters.

The Colville/ which is the largest river of the Arctic slope, enters the sea 

about 80 miles east of Smith Bay. Its headwaters were explored in 1886 by 

Stoney a and Howard, and its lower course and its chief tributary, the Anaktuvuk, 

by Schrader" and Peters in 1901.

Chandler Lake, in which the Colville heads, lies well within the Rocky 

Mountains near the intersection of the sixty-eighth parallel and the one hundred 

and fifty-third meridian. The lake is about 10 miles long and from one-half mile 

to a mile in width and the adjacent mountains rise 1,000 feet above its surface. 

A low divide, called Navy Pass, affords a portage route from the lake to Alatna 

River.

Below the lake the Colville Valley trends northerly, but in 10 miles swings to 

the southwest, then west, and receives a tributary from the northeast. The westerly course continues for upward of 100 miles, when the valley swings to the north,

« Howard, W. L., Expedition to Point Barrow: Naval Explorations in Alaska, pp. 71-77. Native name of this 

river is Ikipikpung.

b On some maps called the Ikipikpung or Ikpikpub.

o Called by the natives Kuyanuk.

d Naval Explorations in Alaska, pp. 44-47 and 70-72.

eSchrader, F. C., Recent work of the United States Geological Survey: Bull. Am. Geog. Soc., vol. 34, 1902, pp. 9-16. 

Geological section of the Rocky Mountains in northern Alaska: Bull. Gcol. Soo. America, vol. 13, 1902, pp. 233-252. Reconnaissance in northern Alaska: Prof. Paper U. S. Geol. Surv. No. 20, 1904, pp. 46-49.
102 GEOGKAPHY AND GEOLOGY OF ALASKA.

and near this angle Etivluk River is confluent from the southeast. The Etivluk 

heads opposite Noatak waters, with which there is easy communication by Riley 

Pass. Up to the northerly bend and for 10 miles farther downstream the valley is 

probably rather narrow and lies within the mountains, but near latitude 68° 30' the 

river emerges into the piedmont plateau region. There the valley bends eastward 

and broadens out, while the river channels become more tortuous. Howard estimated its width near this point at 400 to 1,000 yards, and reports that it was studded 

with islands and sand bars. Between the one hundred and fifty-seventh meridian 

and the Anaktuvuk, a distance of about 70 miles, the Colville is entirely unexplored.

The Anaktuvuk, which is the largest tributary of the Colville, heads in Anaktuvuk Pass, which has au altitude of about 2,400 feet and marks a decided break in 

the Rocky Mountains, and from which the John River flows southward into the 

Koyukuk. This pass is only a few miles from where the range falls off to the 

piedmont plateau on the north, and the Anaktuvuk soon leaves the mountains. 

The intermontane part of its valley is wide, with abrupt walls, and is only about 15 

miles in length, in which distance the river descends over 200 feet. Leaving the 

mountains, it enters a broad basin 40 miles in length, which has been incised in the 

Anaktuvuk Plateau and which receives several tributaries. Below the basin is a 

small canyon, and there the valley broadens again to 2 or 3 miles, and continues 

with about this width to latitude 69°. There it is joined by the Nanushuk from the 

southeast and the Tuluga from the southwest. The valley gradually broadens to 

where it merges with that of the Colville near latitude 69° 30'.

The mountains at the headwaters of the Anaktuvuk reach altitudes of 6,000 

feet, giving a topographic relief of about 3,500. Near the mountains the elevation 

of the plateau is 600 feet, while near the junction with the Colville it is 400 feet. 

Above and in the canyon the Anaktuvuk has many rapids and its bed is strewn with 

glacial bowlders; the lower river has a current of from 2 to 6 miles.

Below the mouth of the Anaktuvuk the Colville flows due north for about 40 

miles. The west side of its valley is well defined by a series of bluffs 200 to 400 

feet high, but the east slope rapidly recedes and gives place to a broad, marshy 

lowland dotted with lakes. Near latitude 70° the Colville bends sharply to the east 

and 10 miles below turns to the north. At this point it enters the coastal plain 

proper and is joined by the Itvelik River, a large easterly tributary. The delta of 

the Colville has a frontage of about 25 miles on the ocean and extends back about 

10 miles. From the junction of the Anaktuvuk to the mouth of the Itvelik the 

Colville has a current of 3 to 4 miles an hour, with some small rapids, but 

below the Anaktuvuk and in the delta there is almost slack water. Stunted 

willows are found as far north as the mouth of the Anaktuvuk, but below that 

point even this shrubbery is entirely absent.

The lower Colville could be ascended by steamer, but navigation has no commercial importance. The Colville Valley is, however, a well-established route of 

travel by which the Eskimos of the upper waters of the Kobuk, Noatak, and 

Colville reach the Arctic coast. In the spring the natives follow the caribou northward to the edge of the mountains, and then after the ice breaks reach the coast by 

boats down either the Colville or the Chipp. The return is made by boats to the 

head of navigation and after winter sets in by dog teams. The wood for constructing
ARCTIC DRAINAGE. 103

the boats is brought either from the driftwood of the coast or across the divide from 

the valleys of the southerly and westerly flowing rivers. Both the coast and interior 

of this bleak northern region supports a large population of Eskimos.

Little is known of the Arctic drainage east of the Colville, but there are probably 

many small rivers which head on the northern slope of the mountains and flow 

northward to the sea.

During the winter of 1902 and 1903 Mr. S. J. Marsh, of Nome, made a remarkable 

journey from Caniden Bay on the Arctic Ocean to Fort Yukon by way of the Chandlar River. Marsh, who traveled alone, made a sketch survey" throughout this difficult 

journey, and by his unaided efforts explored a region entirely unknown to white 

men. He reports four rivers 6 of considerable size which enter the Arctic Ocean 

between the one hundred and forty-fifth and one hundred and forty-ninth meridians. 

The Kupowra is the most westerly river of this group, and probably has its source 

opposite an eastern tributary of the Colville. The Sawanukto River, a much larger 

stream, enters the Arctic through a broad delta about 20 miles east of the Kupowra 

River. It has its source in a divide which lies well within the mountains and whose 

southern slope drains into the Middle Fork of the Koyukuk. Near the sixty-ninth 

parallel the Sawanukto receives from the southeast an important tributary, which is 

said to be separated by a low pass from Koyukuk waters. The Savaovik River flows 

into the Arctic near the one hundred and forty-seventh meridian. It is a much 

smaller stream than either of the two last mentioned. The Canning River, whose 

broad delta forms the west side of Camden Bay, is the largest of the four streams. 

It rises near the southern margin of the mountains, opposite streams flowing into the 

Chandlar River, the two watersheds being connected by low passes. The Canning 

forks near the sixty-ninth parallel, the two prongs being of about equal size. Marsh 

also noted a fifth stream of smaller size which he calls the Barter River and indicates 

as entering the ocean at Manning Point. The Turner 0 River flows into the Arctic 

Ocean a few miles west of the international boundary. It has its source well within 

the British mountains. Its headwaters are probably 50 to 100 miles from the sea 

and its valley is sharply incised.

SUMMARY.

The Arctic drainage of Alaska comprises two systems of watercourses, which 

trend approximately at right angles to each other. The one which lies entirely 

within the mountains flows through a series of large basins connected by narrower 

stretches of valley, with a general east-west trend parallel to the mountain axes. 

The Kobuk, Noatak, and Colville are the largest rivers of this system and receive 

their waters entirely from the ranges of the western end of the Rocky Mountain 

system.

The second drainage system comprises those rivers which drain the seaward 

slopes of the Rocky Mountains and usually flow nearly due north. They occupy 

broad, shallow valleys in the piedraont plateau region, and meander sluggishly over 

the coastal plain. The drainage of the northern portion of the Seward Peninsula 

and that of the Arctic slope east of Cape Lisburne, including the lower Colville 

basin, belong to this group.

aThe writer is indebted to Mr. Arthur Gibsou, of Nome, for a copy of this 

frMost of the names which will follow are native, according to Marsh. 

( Report of J. H. Turner, Ann. Kept . I".S. C. and Good. Survey, Pt. I. 1891,

map.

p. 87.
104 GEOGRAPHY AND GEOLOGY OF ALASKA.

HISTORY OF EXPLORATIONS AND SURVEYS.

INTRODUCTION.

The following sketch is based on a rather desultory examination of the literature at odd times during four or five years. While the value of the statements 

would have been much enhanced by the citation of authorities this was not possible 

in the time available for preparation.

The bibliography a appended to this report contains the titles of all the works 

consulted, which are only a small part of the voluminous literature upon Alaska. It 

has been possible to make a more or less careful study of the important publications 

relating to the Territory since its acquisition by the United States, but many of 

those which deal with the earlier period, particularly the Russian, were not consulted, and the writer has had to rely in part on the three standard works on Alaska 

which contain important summaries of its history. These are: Alaska and Its 

Resources, by William H. Ball, 1870; Report on Population, Industries, and 

Resources of Alaska, by Ivan Potrof, Tenth Census, vol. 8, 1884, and History of 

Alaska, by Hubert Howe Bancroft, 1886.

GEOGRAPHY AS BELATED TO DEVELOPMENT.

The history of Alaska will be more easily understood if the avenues of approach 

for explorers and settlers are briefly discussed. Alaska's peninsular form and irregular shore line give a coast exposure of great extent (Pis. II and VII). Some of this 

fronts upon the frozen sea and adds little to the accessibility of the country, but much 

the larger part is washed by waters which are open to navigation throughout the year, 

and along this extensive seaboard the first explorations and settlements were made. 

An almost unbroken series of ranges the Pacific Mountain system lies near the 

Pacific shore line and offers a barrier which long prevented inland exploration or 

settlement; for only within recent years have passes through it been discovered. The 

broad, depressed interior area lying' behind this ridge is again cut oft' from the coast 

region on the north and east by another mountain chain, here termed the Rocky 

Mountain system, which also retarded man's approach, because it interposed a 

barrier between the interior of Alaska and that extensive system of waterways of 

northern Canada which enabled the fur traders to find their way across the continent 

from the Atlantic seaboard. This Central Plateau region, as it has been called, 

opens out to Bering Sea, into which it pours most of its drainage through two 

great rivers, the Yukon and Kuskokwim, both of which are navigable and afford 

easy access to the interior.

Another important geographic feature of Alaska in relation to its development 

is its juxtaposition to Asia. The westernmost point of its mainland is visible from 

the Siberian coast across Bering Strait, only 60 miles wide; but as this strait is

«The publication entitled, " Partial List of Charts, Maps, and Publications Relating to Alaska and Adjacent Kegions, 

by W. H. Ball and Marcus Baker," Pacific Coast Pilot, Appendix 1, Meteorology and Bibliography, U. S. Coast and Geodetic Survey, Wawlrington, 1879, has not yet been supplemented and remains to-day the only bibliography of works relating 

to Alaska.
HISTOKY RUSSIAN EXPLORATIONS. 105

navigable only in summer, it is of less importance as a route of travel than the 

Aleutian Islands, which form a chain almost connecting the Asiatic and American 

continents. These islands are mostly intervisible, so that as soon as the western one 

had been reached from Asia even the Eussian traders, who were usually entirely 

unskilled in navigation, could follow the archipelago eastward to the mainland.

MAIN FEATURES OF HISTORY.

A complete history of the discovery and exploration of Alaska would 

involve a consideration of the history of eastern Asia and western Canada, as well 

as of the explorations of the northern Pacific and the Arctic region, and is beyond 

the scope of the present paper. In the few pages here devoted to the subject 

it is possible only to broadly outline the progress of discovery, calling attention 

to a few of the more important expeditions which have added to the geographic 

knowledge of the country and the agencies which were operative in its exploration. 

During the two centuries which have elapsed since white men first obtained definite 

tidings of Alaska, exploration and surveys have been carried on spasmodically by 

various nationalities and under various- auspices. Though the larger geographic 

features are now fairly well known, there still remain some unexplored areas, and 

the topographic mapping is hardly begun.

Explorations of the northwestern corner of America may be said to have been 

made from three directions from the west by the Russians, across Siberia and 

Bering Sea; from the east by the English, through the Mackenzie Valley, and 

from the south by navigators of various nationalities exploring the eastern shore 

of the Pacific.

Before the end of the sixteenth century Russian fur traders crossed the Urals, 

gradually extended their operations eastward across northern Asia, and established 

themselves on the shores of Bering Sea. During this time the French voyageurs 

and their successors of English blood had been making their way westward from 

the Atlantic coast. Reaching the Rocky Mountain harrier they were there held 

in check for over a hundred years, but before the middle of the nineteenth century 

they had surmounted this obstacle and established trading posts on rivers tributary 

to the Pacific and the Bering Sea. Meanwhile the Russians crossed Bering Sea and 

had taken possession of Alaska. By the beginning of the nineteenth century the 

fur trade which had been developed by these two nationalities had left the hands of 

individuals and in both cases had come under the control of a strong company. The 

two rival fur-trading interests, which had been moving toward each other for upward of two centuries, after practically encircling the globe finally came into competition in Alaska. These facts are recited here because the desire to obtain control of 

and exploit the fur trade was directly or indirectly the prime motive for the early 

explorations of the territory.

EARLY RUSSIAN EXPLORATIONS. «

Less than a century after the discovery of the American Continent Yermae 

Timofeief and a band of Cossack adventurers crossed the low barrier of the Ural 

Mountains and began that series of conquests in Siberia which was to make Russia

a For the authorities consulted in preparing this sketch see pp. 298-308.
106 GEOGEAPHT AND GEOLOGY OF ALASKA.

an Asiatic power. While the western nations of Europe were exploring the east 

coast of North America, and almost before they had obtained a foothold on its 

shores, the Russian Cossacks had crossed northern Siberia and in 1638 reached the 

sea of Okhotsk. Step by step these Cossack adventurers made their way across 

the great lowlands of northern Siberia, traveling with horses by land and skin 

boats by water. The comparatively peaceful character of the natives and the 

absence of mountain barriers greatly facilitated the work of conquest.

After reaching salt water it was but natural that the Cossacks should extend 

their explorations along the coast. In 1648 Deshnef sailed eastward from the 

mouth of the Kolyma on the Arctic, rounded East Cape, passed through the body 

of water afterwards named Bering Strait, and wintered at the Anadir River. 

More than half a century elapsed before this exploration was extended by another 

Cossack, Popof, who, in 1711, was sent to East Cape to induce the natives to pay 

tribute. The warlike Chuckchees, who inhabited that part of the Siberian coast, 

refused to acknowledge the sovereignty of Russia, but Popof brought back an 

acc9imt of the Diomede Islands in Bering Strait and rumors of a continent said 

to lie to the east.

In course of time news of this discovery was transmitted to St. Petersburg, 

and the reigning sovereign, Peter the Great, was quick to realize its importance. 

Spurred on, no doubt, by the knowledge he had of the discoveries and settlements 

made by the western nations of Europe in the New World, Peter ordered the 

organization of an expedition which should verify Popof's statements and extend his 

explorations. Vitus Bering, a Dane and fleet captain in the Russian navy, was 

placed in charge of the expedition. Peter did not live to see his plans executed, 

dying soon after signing Bering's orders; but his successor, the Empress Catharine, 

actively carried out the purpose of her husband. Bering's command, after crossing 

Siberia, built two small vessels at Okhotsk. In July, 1728, he sailed northward 

along the coast of Siberia as far as East Cape, passing through the strait which 

bears his name. From East Cape he stood to the northeast for a day and then 

returned to his port of embarkation without having sighted the American Continent.

While Bering himself believed that his short voyage definitely proved the 

absence of an eastern connection of Asia with North America, yet so meager was 

his evidence that most geographers refused to accept it, and it was not until Cook's 

voyage, half a century later, that convincing proof was obtained. Bering did, 

howeyer, discover and name St. Lawrence Island, and may therefore be regarded 

as the first white man to look upon any part of what is now Alaska.

Three years later a vessel in command of a Cossack named Grwosdfcf, one of a 

small fleet sent to subdue the Chuckchees, was blown onto the American coast by a 

storm, probably somewhere in Norton Sound. The records of this voyage, vague 

as they are, contain the first reference to the mainland of Alaska based upon the 

actual observations of white men. In the following year (1729) Bering made a 

second voyage, which was even less fruitful of results.

The interest excited by these discoveries led to the organization at St. Petersburg of another expedition, of which Bering was again put in command. Such 

were the difficulties of travel that six years were spent in transporting the party 

and outfit across Siberia, which at that time afforded nothing except game, fish,
HISTORY RUSSIAN EXPLORATIONS. 107

and furs, so that all supplies, including the ironwork and tools necessary for the 

construction of ships, had to be brought from Europe. Finally, in 1741, the 

expedition sailed from Okhotsk in two vessels, one commanded by Bering himself and the other by Chirikof. These soon became separated, and Bering, sailing 

eastward, on July 18 fell in with the American coast near Mount St. Elias, 

which he named, and a few days later landed on what was probably Kayak 

Island.

With this discovery Bering seemed to consider that his mission was fulfilled, 

and after a very cursory examination became impatient to return to Asia. The 

expedition, which had taken years of preparation, turned westward without 

attempting surveys or investigations and without even making a landing on the 

mainland of the newly discovered continent. Sailing southwest they discovered 

the Shumagin Islands, and named them after a member of the crew who was 

buried there.

Bering's haste to return to Asia again prevented him from making an 

adequate exploration. He continued westward along the line of the Aleutian 

Islands, some of which he sighted, but without gaining more than a very superficial knowledge of them. Scurvy broke out among the crew, and the entire 

party seems to have been bewildered. They sailed hither and yon, now heading 

for the American, now for the Asiatic coast, at last wrecking their vessel upon 

Bering Island of the Commander group, now belonging to Siberia. Of those 

that reached the shore many died, among them Bering, a disheartened and 

despairing man. The cross over his grave was the first emblem marking the 

extension of Russian sovereignty eastward of Siberia. The survivors of the illfated expedition built a small vessel of the wreckage and returned to Kamchatka.

Chirikof's voyage was even less successful. After becoming separated from 

Bering he sailed eastward, and on July 15 sighted the continent, probably near 

Cross Sound. An attempt to land ended disastrously, for both boats were lost, 

and nearly a third of the crew were killed by the natives. Chirikof hastily put 

to sea and returned to the Asiatic coast, sighting some of the Aleutian Islands in 

his passage.

The explorations made by these two navigators, while not fruitful of results 

commensurate with the elaborateness of the preparations, were yet of the utmost 

importance from a geographic standpoint. Two points on the American Continent were fixed with a fair degree of accuracy and the location of some of the 

Aleutian Islands approximately established. These islands, which are part of the 

broken chain connecting the Asiatic and North American continents, were to 

become an important factor in the early development of the fur trade of Alaska.

The reports by Boring's crew of the existence of valuable furs in the newly 

discovered islands east of Kamchatka soon led the hardy Siberian fur hunters, called 

promyshleniki, to brave the perils of an unknown sea. The first of these was Bassof, 

who two years after Bering's return reached Bering Island in a small vessel. The 

rich harvest of furs with which he returned after a year's absence induced him to 

make a second, and later a third voyage. He was but the forerunner of a swarm of 

promyshleniki who gradually pushed their way eastward along the Aleutian chain 

of islands to the mainland of Alaska.
108 GEOGRAPHY AND GEOLOGY OF ALASKA.

These Siberian fur hunters had up to this time but little knowledge of deep-sea 

navigation, an ignorance which fitted them in a measure for the task which they had 

undertaken, for experienced seamen would have refused to take part is such utterly 

hazardous and foolhardy enterprises. As all iron for shipbuilding on the Bering 

Sea had to be transported across Siberia to Kamchatka, the result was that a species 

of vessel was devised which could be constructed without iron, the planks being 

sewed together with thongs of rawhide in lieu of nailing. Provisions also were 

scarce in Kamchatka, and these roving traders depended largely on such food as 

could be obtained from the sea.

In these crude crafts, manned by crews which knew little of seamanship, 

and usually but ill-equipped and provisioned, these intrepid fur traders boldly 

pushed out into unknown stormy seas. Many lives were lost by wrecks, starvation, 

and scurvy, and man}' of the adventurers met deserved death at the hands of the 

outraged natives. The risks were great, but when the expeditions were successful 

the profits were enormous, and the necessary capital for such enterprises was easily 

procured among the merchants of eastern Siberia.

This vanguard of civilization was made up of men who had no virtues other 

than valor and intrepidity. Their gradual mastery of the Aleutian Islands, which 

led to Russia's becoming a North American power, is a tale of blood and rapine, of 

murder and outrage. Under plea of exacting tribute from the natives they took 

their furs by force and not by barter, practically reducing the natives to slavery. 

Their firearms gave them an incalculable advantage over these people, whose arrows 

and spears were still tipped with bone. The Aleuts, at first friendly to the strangers, 

only too soon learned their true character; and though not so warlike as the true 

Eskimos to the north, or the Haidas and Thlinkets of southeastern Alaska, with 

whom the Russians later came in conflict, did not give up without resistance. Many 

a bloody and well-deserved reprisal did they inflict on their oppressors. The struggle 

was, however, hopeless; ravages of the barbaric Siberian fur traders during the half 

century succeeding- Bering's discoveries threatened to exterminate the indigenous 

population of the Aleutian Islands. While the outrages were largely the work of 

private individuals they received a certain sanction from the Russian Government, which allowed the traders to plunder and murder the natives at will, but 

was ready enough to exact tribute on the ill-gotten furs. The cry of the murdered 

and outraged Aleut did not reach St. Petersburg, or if it did was not heeded.

It was through this murderous crew of traders that the civilized world learned 

of the Aleutian Islands and the adjacent mainland. Russia was to owe her American 

colony to the initiation and enterprise of private individuals, for the Court of St. 

Petersburg paid little heed to its American possessions for more than half a century 

after Bering's last voyage. But two attempts at official investigation were made, 

both more or less abortive. In 1767 Lieutenant Synd, of the Russian Navy, was 

sent out to explore the American coast, and though his results were meager and his 

statements unreliable, there seems no reason to doubt that he landed on the southern 

coast of Seward Peninsula. About the same time Captain Krenitzin reached the 

Alaska Peninsula on a similar mission.

When the Spanish and English first appeared on this coast Russia had no permanent settlement in Alaska. Bering's expedition had discovered a new continent;
EXPLORATIONS OF ALASKA. 109

yet though a third of a century had passed during which private enterprise had 

developed a lucrative fur trade in the adjacent islands, no effective attempt had been 

made to extend his discoveries or to exploit the resources of the main continent. 

The trading voyages had approximately established the relative location and configuration of the Aleutian Islands and Kodiak. Krenitzin had astronomically determined 

a few positions in the eastern part of the chain and along the southern coast of the 

Alaska Peninsula. These, together with Bering's discovery, and a less definite 

knowledge of the mainland lying adjacent to Bering Strait, comprised Russia's investigations in North America previous to the advent of other nations.

EXPLORATION BY K1VAL NATIONALITIES.

While the Eussian influence was extending over Alaska from the west the 

Spaniards were approaching it from the south, where they had established themselves 

on the coast of California. Reports of these Russian encroachments led the viceroy 

of Mexico to send out several successive expeditions to explore the coast and where 

they found it uninhabited to plant the arms of Spain. Perez, a Spanish ensign, discovered the Queen Charlotte Islands in 1774, and the following year Lieutenant 

Quadra explored as far north as Cross Sound.

The first important systematic survey of any part of what is now known as 

Alaska was made by Captain Cook, the great English navigator. Cook sailed from 

England with two vessels in 1776. His first landfall on the Alaskan coast was in 

May, 1778, near Mount Edgecumbe, previously discovered by Bodega y Quadra. 

Thence he sailed westward, exploring Prince William Sound and Cook Inlet as far as 

Unalaska, where he was received very kindly by a band of Russian traders. It is of 

interest to note that an American in Cook's vessel, John Ledj^ard, was the first to 

interview the Russians.

Cook now entered Bering Sea and continued his surveys of the coast toward 

the north, through Bristol Bay, Norton Sound, and Bering Strait, until he was 

checked by the Arctic ice pack. This he skirted westward to where it impinged on 

the Siberian mainland at a point which he named Cape North, whence he returned 

to the south along the Siberian coast. The winter was spent in the Hawaiian 

Islands, and there the famous navigator met his death. The following year his 

vessels set out again under the command of Clerke, in an attempt to extend the 

surveys farther north, but the ice pack again interfered before they had penetrated 

much farther than before.

Cook had been unsuccessful in finding the water passage to Hudson Bay which 

he sought, but in the course of a single summer he had accomplished many times as 

much as all previous explorers. His voyage outlined the larger coastal features of 

Alaska, from about latitude 58° to 70°; definitely established the fact that there 

was no land connection between America and Asia, and convinced the navigator 

himself of the futility of seeking a waterway to the Atlantic, a conclusion which 

was in part based on Hearne's exploration in 1771 from Hudson Bajr to the mouth 

of the Coppermine River. This last result was not generally acknowledged, and it 

remained for one of Cook's officers, Vancouver, to bring the final proof not even 

then accepted by the theoretical geographers about fifteen years later. 

17211 No. 45 06 8
110 GEOGRAPHY AND GEOLOGY OF ALASKA.

Great as was Cook's contribution to the geography of the Alaskan coast, 

perhaps of still more lasting importance was his inauguration of a new era in the 

explorations of the Alaskan seaboard. The vague and haphazard reports of the 

previous explorers were replaced by concise charts and accurate observations, many 

of which have stood the test of more detailed investigation. Several officers who 

accompanied Cook and were trained in his methods returned in later years to the 

Alaskan coast and continued the work of exploration.

Though some of the promyshleniki had reached Kodiak as early as 1762, it was 

not until after Cook's voyage that, finding the sea otters were becoming relatively 

scarce among the Aleutians and the voyages less profitable, they began to seek new 

hunting grounds to the northeast. Up to this time the fur gathering had been in 

the hands of individuals or small, weak companies, and hence but little concerted 

effort had been made. In 1781 a company of eastern Siberian merchants was 

formed for exploiting the American fur trade. The leader of this organization was 

Gregor Ivanovich Shelikof, who, with Ivan Golikof, controlled a majority of the 

shares. Under Shelikof's leadership an expedition was sent out, which, in 1783, 

founded a colony at Three Saints Bay, near the southern end of Kodiak Island. 

This was the first settlement within the limits of Alaska and was the pioneer of the 

Russian occupation, which was to last for three-quarters of a century, until the territory was transferred to the United States.

In the year this colony was founded a group of trading vessels, under the command of Potan Zaikof, reached Prince William Sound. He attempted the same 

high-handed proceedings which had been so successful among the Aleuts, but found 

to his cost that he was dealing with a fierce, warlike population, and the expedition 

ended disastrously. The event was noteworthy, as it was the first time the Russian 

traders are definitely known to have reached the mainland. Nagaief, a member of 

this party, discovered the Copper River and ascended it a short distance.

In the meantime the published account of Cook's voyage had aroused other 

nations to the fact that the rich fur trade in the northwestern extremity of the 

American continent was rapidly passing into the hands of the Russians. The English traders were the first to follow it up. In 1785 James Hanna visited the west 

coast of Vancouver Island, in British Columbia, and in the succeeding years made 

several voyages to the coast of what is now Alaska. Similar trips were made by 

English and American trading vessels and ships of other nationalities. The published logs and track charts of a number of these vessels added to the general 

knowledge of the northwest coast. All of these the Russians regarded as unlawful 

intruders, and many petitions were sent to St. Petersburg protesting against foreign 

ships engaging in this trade.

While merchants and traders of various nationalities were struggling for commercial supremacy in Alaskan waters, their home governments were not unmindful 

of the political side of the controversy. The English, Spanish, and French governments showed a desire to wrest some of these new discoveries from the Russians. 

The Spaniards claimed the coast, because it was a northern extension of their California possessions, and also by right of the discoveries of Bodega y Quadra. The 

English claim rested on Cook's discoveries.
EXPLORATIONS OF ALASKA. Ill

The Spanish claims were strengthened by an expedition led by Arteaga, with 

Quadra as second in command, which sailed northward from Mexico in 1779, and 

visited and surveyed Port Bucareli on the west side of Prince of Wales Island. 

Later they entered Prince William Sound and, in obedience to their instructions, 

took formal possession of what they believed were newly discovered lands. They 

little realized that Cook in the previous year had gone through the same ceremony 

in the name of the British sovereign almost at the same spot. After extending their 

explorations to the southwest as far as the southern end of the Kenai Peninsula they 

returned to Mexico.

The French had no part in the discovery or in the exploitations of the new 

country; but to gain a valid claim, La Perouse, a naval officer, was dispatched 

to the northwest coast in 1785. In the following year he landed at Lituya Bay, 

of which he made a detailed examination and took formal possession. Then, 

ignoring his instructions to survey the Aleutian Islands, he sailed southward 

without landing again on the Alaskan coast.

The Spaniards, apparently satisfied that Arteaga's explorations established 

their territorial claims, took no further action for several years. The publication 

of Cook's voyages and the report of the numerous trading vessels that visited the 

northwest coast, however, aroused them again from their lethargy. In 1788, two 

vessels, commanded by Estevan Martinez and Gonzalez Haro, were dispatched 

northward to gain further information. While Martinez explored Prince William Sound, Haro visited the Russian establishments on Kodiak Island, and 

obtained full knowledge of the Russian occupation. Delarof, the director of the 

colony, took pains to impress the Spaniard with the wide extent and importance 

of the Russian settlements, of which at that time there were only six. After 

visiting Unalaska and going through the absurd performance of taking possession 

in the name of His Most Catholic Majesty of an island which contained a Russian 

colony and had been under Muscovite influence for upward of a quarter of a 

century, the expedition sailed for Mexico.

Martinez's report of the Russian occupation showed the viceroy of Mexico 

that Spanish claims to the northwest coast must be enforced by more decisive 

action. Both vessels were therefore again dispatched to take immediate possession of Nootka Sound on the west side of Vancouver Island, which had been 

discovered by Cook and had been used as a rendezvous by English, American, 

and Portuguese traders. The Spaniards did not molest the American ships, but 

warned off all those flying English colors. This high-handed action led to an 

immediate protest by the British Government, and commissioners were appointed 

by both governments to come to an understanding. The first meeting at Nootka 

led to a disagreement; but subsequently the Spaniards receded from their position 

and withdrew their forces, leaving the region in the possession of the traders 

and natives.

In 1791 Malaspina, an Italian navigator, in command of two Spanish corvettes, engaged in a scientific exploration which was to encircle the globe. He 

was sent to the northwest coast to explore for a northwest passage, rumors of 

which were again gaining credence. He made landfall near Mount Edgecumbe,
112 GEOGKAPHY AND GEOLOGY OF ALASKA.

and tracing the coast to the northwest entered Yakutat Bay, then known as Port 

Mulgrave. The ceremony of taking possession of the newly discovered land was 

not omitted, though Portlock and Dixon had surveyed and published a chart of 

the bay some years before, and the Russians had long used it as a rendezvous 

in their fur-trading expeditions. Malaspina made a cursory examination of Prince 

William and Cross sounds, and then turned southward.

George Vancouver, one of Cook's midshipmen, was the English representative 

in the Nootka dispute, and while his conferences with the Spaniards had no 

immediate result, his later explorations were of the utmost importance. He 

received orders to survey the coast between the thirty-fifth and sixtieth parallels 

of latitude, a task which he faithfully executed with his two vessels in 1793 

and 1794. In the course of two seasons he accurately delineated thousands of 

miles of the coast line of southeastern Alaska, and supplemented the work of 

previous explorers westward as far as Cook Inlet. Not an indentation of the 

mainland, hardly a break in the shore line of the numerous islands, escaped his 

notice. His would have been a difficult task even in the days of steam, and to 

thread the intricate waterways of the Alexander Archipelago and make such surveys as he did within so short a period was little short of marvelous. He was 

a worthy successor of the great Cook, under whom he had learned navigation 

and geodesy. After his task was completed the general features of the entire 

coast line of the mainland of Alaska from Dixon Entrance as far north as Cape 

Belcher were charted with a fair degree of accuracy.

While the Russians and the Spaniards were attempting to dispossess all other 

nations of commercial and territorial rights in the coastal zone of Alaska, the 

English, their most aggressive rivals, were steadily approaching the region from 

the east. The French pioneers, following the route of the Great Lakes, had 

crossed half of the American continent long before the Russians had knowledge 

of the Aleutian Islands, and about the time of Bering's discovery of the mainland of Alaska, Verandrye had reached the foothills of the Rockies near the 

headwaters of the Missouri. Ten years later another pioneer trader established 

a post at the present sight of Calgary (Alberta), at the very base of the Rocky 

Mountains and only 500 miles from the Pacific waters. This post, with many 

others, was abandoned when Canada passed into the hands of the English.

Henceforth the English fur trade gradually expanded into the region which 

had been pioneered by the French. The Rocky Mountain barrier for a long 

time marked the limits of this western fur trade. It remained for Alexander 

Mackenzie to surmount this barrier, and to introduce a new factor in the development of Alaska. Mackenzie, who was a member of the Northwestern Fur 

Company, the great rival of the Hudson Bay Company, ascended the Peace River 

from Lake Athabasca, crossed the Rocky Mountains, then traversed the headwaters 

of the Fraser, and after crossing the Coast Range reached Pacific waters in the 

latitude of Queen Charlotte Sound. This journey, which was the first made across 

the continent north of Mexico, was accomplished in 1793, at the same time that 

A^ancouver was surveying adjacent waters. It was the forerunner of the fierce 

rivalry which was to spring up between the two great competitors in the fur 

trade, the Russian-American and Hudson Bay companies.
RUSSIAN OCCUPATION. 113

In spite of the small degree of success achieved by previous official explorations, 

the authorities at St. Petersburg in 1785 determined on another. This was placed in 

charge of Joseph Billings, who seems to have been chosen more because he had been 

attached to one of Cook's vessels than because of uny particular merit or experience. 

Billings sailed from Kamchatka in 1789, and passing through Bering Strait penetrated the Arctic Ocean to about latitude (59° and then returned to Kamchatka. In 

1790 he made a second start, and the two vessels of the expedition, stopping at 

Unalaska and Kodiak, reached Prince William Sound, and then again returned to the 

point of debarkation. In the following year a third start was made and Billings 

once more reached Unalaska, whence he sailed northward, touching at Pribilof 

Islands, Seward Peninsula, and St. Lawrence Island. Billings himself afterwards 

landed on the Chuckchee Peninsula, Siberia, where he made a hazardous but 

apparently bootless journey inland. The two vessels wintered at Iliuliuk, Unalaska 

Island, and the following year returned to Kamchatka. The expedition, which in 

its preparation and execution had cost seven years of time and large sums of money, 

accomplished almost nothing beyond gaining some information regarding the abuse 

of the natives by Russian traders.

RUSSIAN OCCUPATION.

The last two decades of the eighteenth century were to witness important 

changes in the Russian fur trade. The Shelikof Company, after its settlement on 

Kodiak in 1783, gradually extended the sphere of its trading operations to the 

neighboring islands and mainland. In 1788 an imperial ukase granted to this company the exclusive control of the regions actually occupied by its agents. In 1792 

an important step was taken in appointing Alexander Andreivich Baranof, chief 

director of the company's American interests. Baranof, who held this post for 

twenty-five years, showed himself to be a far-sighted, energetic man, though coarse 

and unscrupulous. The early years of his administration were a fitting introduction 

to the stormy ones to follow. At Cook Inlet rival traders had established themselves, who for some time quarreled and fought among themselves, but finally united 

to oppose their common enemy, the Shelikof Company. At length Baranof was 

forced to assume authority which he did riot legally possess, and restored some 

measure of peace by arresting and imprisoning the ringleader.

In the meantime Baranof was energetically looking after the interests of the 

company in other directions. A shipyard was established on Prince William Sound, 

and attempts were made at agriculture at Kodiak and Yakutat Bay, while the fur 

trade was pushed vigorously. The first Greek Catholic missionaries arrived from 

Siberia in 1794, and at the same time the first convicts were imported and settled at 

Yakutat.

At the close of the century the court at St. Petersburg was beginning to be 

moved by reports of the disorders and outrages committed by the irresponsible fur 

traders, and was becoming weary of the quarrels of the rival companies. It was, 

moreover, desirous of maintaining Russian prestige in America by a responsible 

representation. Thus it happened that the Shelikof Company, with the aid of 

financial backing, was able to obtain a new charter under the name of the Russian-
114 GEOGRAPHY AND GEOLOGY OF ALASKA.

American Company. The imperial ukase which established this company was dated 

1799, and granted exclusive privileges of trade and occupation of northwestern 

America, lying north of latitude 55° and including the Aleutian Islands. The 

original grant was for twenty years, but two extensions placed Alaska in the hands 

of this company for sixty years. From this time on the history of Alaska up to its 

transfer to the United States is practically the history of this company which 

controlled this great monopoly. The region being now definitely in the hands of the 

Russians, the limits of whose possessions were determined by treaty with England 

in 1825, other nations discontinued their explorations.

"In its early history the Russian-American Company was too much engrossed in 

developing the commercial resources of its grant to make any attempts at extensive 

explorations or surveys. However, as its agents gradually enlarged their field of 

operations, they gained some knowledge of new areas. The hunting trips had 

already reached southeastern Alaska, and in 1799 Fort Archangel Gabriel was built 

on Baranof Island, in Sitka Bay. The warlike Thlinkets of this region were far 

from submitting to Russian transgressions as did the Aleuts, and during the entire 

Russian occupation they proved themselves aggressive neighbors. In 1802 they 

attacked and demolished Fort Archangel Gabriel, and the few survivors were only 

saved by the timely arrival of an English vessel. Two years later Baranof set upon 

the Thlinkets in force and drove them out of their stronghold, Sitka, of which he 

took possession. He soon moved the capital of the colony from Kodiak to this new 

post, which he called New Archangel.

During the early part of the nineteenth century the activities of the colony, 

under Baranof's directorship, were in the main confined to commercial lines. But 

several minor explorations were undertaken, chiefly by naval officers who were in 

the service of the compan}7 . Thus it happened that Khwostof and Davidof made 

investigations among the Aleutian Islands in 1802. In the following year Bassanof 

visited the Copper River; and surveys were made in the Alexander Archipelago 

and the vicinity of Kodiak by Captains Krusenstern and Lisiansky in 1804 and 1805.

When Captain Golofnin of the Russian Navy was sent out by the home 

government in 1810, and a second time in 1818, for the purpose of investigating the 

affairs of the company and the status of the natives, some contribution was again 

made to geographic knowledge, though only incidentally.

The most important exploring voyage of this period was undertaken in the brig 

Rurik by Otto von Kotzebue, of the Russian navy. His purpose was the general 

advancement of scientific knowledge, including the discovery of a northeast waterway, in the existence of which many geographers still obstinately believed. Sailing 

from Kronstadt in 1815, Kotzebue reached Kamchatka the following year, whence 

he headed for Bering Strait. He touched at St. Lawrence Island, rounded Cape 

Prince of Wales, and coasting along the north side of the Seward Peninsula entered 

and surveyed the great sound which bears his name. On his return passage he 

visited Unalaska. After wintering in the Hawaiian Islands Kotzebue made a second 

trip to Alaska, but did not extend his former surveys.

No systematic explorations or surveys had been attempted under Baranof, but a 

change came about when the directorship of the Russian-American colony was 

transferred to naval officers, several of whom were men of scientific tastes and
RUSSIAN OCCUPATION. 1 15

training and did much to foster geographic investigations. Other sciences were not 

neglected; systematic meteorologic records were kept at Sitka for many years, and 

a magnetic station was also maintained. Of the directors of the colony Baron F. P. 

von Wrangell was most prominent. Coming to his post fresh from Arctic explorations, he naturally looked with favor on all geographic investigations, and it was 

under his regime that the most important of the explorations carried on by the 

company were undertaken. This work was actively furthered by one of Wrangell's 

successors, Capt. Michael D. Tebenkof, who was also an explorer. Tebenkof's atlas 

of the northwestern coast of America, comprising a summary of all previous investigations, is the most important contribution to the geography of Alaska made 

during the entire Russian occupation.

In 1826 began the most valuable coastal exploration made by the RussianAmerican Company. This expedition, under the direction of Kramchenko, Etolin, 

and Vasilief, spent two years in examining the shore line of Bristol Bay and Norton 

Sound. In the following year Captain Liltke, sent out by the authorities at St. 

Petersburg, visited Unalaska and the Pribilof Islands and made a careful survey of 

the northern coast of the Alaska Peninsula. The southern coast of the Alaska 

Peninsula was mapped a few years later by Vasilief.

Among the lesser expeditions made under the direction of the company may be 

mentioned the explorations of the Bristol Bay and Kuskokwim regions by Korsakof, 

Vasilief, and Kolmakof from 1818 to 1832, and Malakof's exploration of the 

Sushitna in 1834. A more important expedition was one in charge of a ereole by 

the name of Andrei Glasunof, who crossed from the Russian post at St. Michael, 

Morton Bay, to the Yukon and thence to the Kuskokwim. This, with Malakof's 

trip up the Yukon as far as Nulato, paved the way for the exploitation of the fur 

trade of the Yukon River.

By far the most fruitful of the Russian inland explorations was that made by 

Lieutenant Zagoskin, of the Imperial navy, in 1842-43. Zagoskin ascended the 

Yukon as far as the mouth of the Tanana and explored the lower stretches of the 

Koyukuk. Under his auspices a post was built at Nulato. He also traversed the 

Innoko, an easterly tributary of the lower Yukon, and made his way eastward to 

Kuskokwim waters. As far as time and means would permit, Zagoskin made track 

surveys and astronomic determinations of position, meanwhile taking careful notes 

on the native population and the resources of the region traversed. In the light of 

subsequent developments it is of interest to note his statement that the Yukon, or 

Kwickpack as he called it, was not navigable above the mouth of the Tanana.

In the meantime activity in Arctic exploration once more drew the attention 

of English navigators to the northwest coast. In 1789 Alexander Mackenzie had 

followed to the Arctic Ocean the great river which bears his name. In 1826 Sir 

John Franklin had traversed the Arctic coast westward, from the mouth of the 

Mackenzie as far as Return Reef on the north Alaskan coast; and Capt. F. W. 

Beechey, of H. M. S. Blosscrm, who had been dispatched to cooperate with Franklin, 

carefully charted the southern coast of the Seward Peninsula to Cape Prince of 

Wales, and added many details to the work of Kotzebue in Kotzebue Sound, 

extending his surveys northward until blocked by ice. A boat expedition under 

Beechey's mate Elson succeeded in reaching Point Barrow, which, it was hoped,
116 GEOGRAPHY AND GEOLOGY OF ALASKA.

Franklin would be able-to reach from the east. But as Franklin was blocked by 

the ice 100 miles east of Point Barro\v, this part of the coast line represented a 

hiatus in the charts for ten years.

In 1837 Peter Warren Deasc and Thomas Simpson, of the Hudson Bay Company, descended the Mackenzie and followed the coast westward. Like Franklin, 

they, too, were stopped by the ice, but Simpson continued on foot and in native 

boats. He reached Point Barrow August 4, 1837, thus completing the exploration of the entire coast line of the mainland of Alaska, which was begun by 

Bering about one hundred years before.

Another impetus to Alaskan exploration was given by the series of Franklin 

relief expeditions which were sent out by the British Government between 1848 

and 1853. While the primary purpose of these expeditions was to find and bring 

relief to Franklin, yet the commanders incidentally accomplished considerable 

exploration and charting. An added stimulus was the hope of finding a northwest passage, which geographers were loath to give up. In 1849 Capt. Thomas 

E. L. Moore in H. M. S. Plover, Capt. Henry Kellett in H. M. S. Herald, and 

the yacht Nancy Dawson, reached Kotzebue Sound. A boat expedition under 

Lieutenant Pullen was sent northward, and rounding Point Barrow proceeded 

eastward to the Mackenzie River, which it ascended to a Hudson Bay post. A 

second expedition from these vessels explored the Buckland River. Other minor 

explorations were made by the crew of the Plover while she wintered in Kotzebue Sound. Thus Lieut. Bedford Pirn crossed the eastern end of Seward Peninsula to the Russian post at St. Michael, and Simpson, surgeon of the expedition, 

explored the Selawik River and made the first mention of the Kobuk River. 

The Plover spent the two following winters at Point Barrow, from which she 

continued to send out exploring parties.

In 1850 Commander Robert S. M. McClure, in H. M. S. Investigator, sailed 

eastward past Point Barrow and beyond the mouth of the Mackenzie until he 

was stopped by the ice. His vessel was never brought through, but eventually 

his crew, by walking over the solid ice, was the first to make the northwest 

passage. The following year Capt. Richard Collinson, in H. M. S. Enterprise, also 

passed Point Barrow, and subsequently wintered at Walker Bay, on the north 

coast of Alaska. In 1853 H. M. S. Rattlesnake, Commander Trollope, wintered 

at Port Clarence, on the south side of the Seward Peninsula, which some of the 

crew crossed during the winter.

The surveys of these Arctic expeditions were very carefully executed and are 

still the bases for most of the charts of the regions they cover. The accounts 

of the voyages are full and contain much valuable information, which up to very 

recent times was all that was available concerning Arctic Alaska.

In 1848 the American whaler Superior, commanded by Captain Roys, ventured 

through Bering Strait, and was amply rewarded by a good catch. This example 

was followed by many others in succeeding years. The whaling industry along 

the Arctic coast of Alaska has continued to be an important one up to the 

present day, though it received a serious setback during the civil war by the 

ravages committed by the Confederate privateer Shenandoah, which captured 

and destroyed many vessels of the American whaling fleet. Stations are now
KUSSIAN OCCUPATION. 117

maintained by the whaling companies at Point Barrow and Herschel Island, east 

of the international boundary. The experienced seamen who usually commanded 

these whalers added not a little to the geographical knowledge of the Arctic 

coastal region of Alaska.

The only other important American contribution during the period of Russian 

control was furnished by Lieut. William Gibson, U. S. Navy, who, in command of 

the schooner Feniinore Cooper, of the Rodgers United States Northern Pacific 

Exploring Expedition, made surveys and explorations among the Aleutian Islands 

in 1855. Some of the other vessels of the same fleet passed through BeringStrait and into the Arctic Ocean.

Many years elapsed after Mackenzie made his explorations to the Pacific before 

the English fur trade was to establish itself near the bounds of what is now known 

as Alaska. Though the Hudson Bay Company was incessantly pushing its outposts 

to the west, it did not reach the drainage basins of rivers which emptied into the 

sea through the Russian American possessions until toward the middle of the 

nineteenth century. Campbell established a Hudson Bay post in 1840 on the 

headwaters of the Pelly, a branch of the Yukon, and eight years later (1848) built 

Fort Selkirk, at the mouth of the Pelly. In the previous year, however, Fort 

Yukon had been built at the mouth of the Porcupine by A. H. Murray, another 

Hudson Bay agent. The English traders of these posts soon learned through the 

natives that the Russians were in possession of the lower river, and, probably about 

1850, some of them made a trip down the Yukon to the mouth of the Tanana, which 

was the uppermost point reached by the Russians in their trading expeditions. 

This was also the point reached by the explorer Zagoskin in his ascent of the river 

in 1843. It can therefore be stated that the preliminary exploration of the main 

Yukon by white men was completed by this journey of the Hudson Bay traders, 

though its first mapping remained to be done by the members of the scientific 

corps of the Western Union Telegraph Expedition.

In 1834 the Hudson Bay Company had by high-handed proceedings attempted 

to establish itself within Russian America, in what is now called southeastern 

Alaska, but it was promptly ejected by the Russian Company. After a conference 

this coastal belt was, in 1837, leased by the Russians to the Hudson Bay Company 

for a term of ten years. The Hudson Bay Company, from its two posts in the 

Yukon drainage basin, controlled the fur trade of the upper river, while the 

Russian-American Company controlled the trade on the lower river.

One other expedition needs mention the last of the Russian official surveys 

in America. In 1863, word having been received at Sitka that American prospectors 

had found gold on the Stikine River, it was decided to send out an expedition to 

find out whether these discoveries were in Russian territory. This party, in 

command of Commander Bassarguine, of the Imperial navy, and accompanied by the 

American geologist, William P. Blake, made a reconnaissance survey of the lower 

part of the Stikine.

In 1863 the Western Union Telegraph Company determined to build an 

overland telegraph line from the western coast of the United States through British 

Columbia and what was then known as Russian America to Bering Strait. This 

line was to be connected by cable with a trans-Siberian line, and thus telegraphic
118 GEOGBAPHY AND GEOLOGY OF ALASKA.

communication was to be established between America and Europe. The project, 

first conceived by Percy M. D. Collins, was a daring one, for it contemplated the 

building and maintaining of a telegraph line through thousands of miles of almost 

unexplored territory in America and Asia. The first essential to the project was 

preliminary exploration of the proposed route. The success of the Atlantic cable 

led to an abandonment of the enterprise only three years after its organization, 

but even in that short time important contributions were made to a geographic 

knowledge of Alaska and adjacent portions of Canadian territory. The explorations 

in Siberia were also, fruitful of important results.

The task which confronted the Western Union Telegraph survey in Russian 

America was not an easv one. The region to be explored was several thousand 

miles distant from the nearest port of the United States. While there were some 

Russian trading posts on Bering Sea and along the lower Yukon, they were widely 

separated and the Russian knowledge of the interior was practically limited to 

the lower part of the Yukon and the Kuskokwim. Moreover, the Russian outposts 

were small and ill equipped, so that practically all supplies had to be taken from 

the Pacific coast ports of the United States.

Robert Kennicott was chosen as head of the scientific corps, serving under 

Capt. Charles S. Buckley, engineer in chief of the expedition. Kennicott was a 

fortunate choice, as he was an able and enthusiastic worker and his previous expedition into the far northwest, in ] 860-61, when he had reached Fort Yukon by 

following the Hudson Bay Company route from the Mackenzie, had fitted him well 

for the undertaking. He did not live to see the execution of his comprehensive 

plans, for he died at Nulato in 1866, his death being brought about by the incessant 

toil and exposure to which he had been subjected. William H. Dall, who took 

the leadership of the scientific corps, continued alone his researches on Norton 

Sound and the lower Yukon after the telegraph survey party was disbanded. His 

book, based on these investigations, and the reports which he wrote later under the 

auspices of the Coast Survey, are still the standard works on Alaska.

In 1865 Robert Kennicott, Frank Ketchum, and Michael Lebarge had started 

up the Yukon. After Kennicott's death at Nulato in 1866 Ketchum and Lebarge 

pushed on up the river to Fort Yukon. In the following year they continued 

their explorations as far as Fort Selkirk, at the junction of the Lewes and Pelly 

rivers. Dall and Frederick Whymper reached Fort Yukon in the summer of 1867, 

after making the first survey of the lower Yukon. In the meanwhile, in 1865, 

Baron Otto von Bendeleben and W. H. Ennis, also of the telegraph survey, made 

an exploration from Golofnin Bay to Port Clarence, and J. T. Dyer and Richard 

D. Cotter crossed overland from Norton Bay to the mouth of the Koyukuk, while 

Capt. E. E. Smith carried on surveys in the delta of the Yukon.

The geographical results of this survey in Alaska are a map of the Yukon 

River, definitely establishing the identity of the Yukon of the Hudson Bay Company 

with the Kwikpak of the Russians, and important additions to the knowledge 

of the Yukon Delta, Seward Peninsula, and the Norton Bay region. It is interesting to note that the route which these first explorers selected has been practically 

adopted by the telegraph lines which are now being constructed in Alaska and in 

Canadian territory. Of still greater importance even than the actual surveys
AMERICAN OCCUPATION. 119

was the more or less exact information which the telegraph survey explorers were 

able to furnish the American public during and after the negotiations by which 

Eussian America became an American possession.

AMERICAN OCCUPATION.

In 1867 the territory of Russian America passed into the hands of the United 

States, the treaty being ratified by the Senate on May 28. The territory, which 

at the suggestion of Secretary Seward was called Alaska, was purchased from 

Russia for $7,200,000.

At the time of the transfer of Alaska to the United States the coast line had 

practically been explored throughout and much of it had been charted with a fair 

degree of accuracy. While the Russian explorations of the coast added many 

details, it can not be denied that the larger part of this work had been done by 

half a dozen English navigators Cook, Vancouver, Beechey, Franklin, Dease, and 

Simpson. Many of the surveys made by these men have not been duplicated and 

are still the basis for all of the existing charts. Soon after the transfer the 

Coast and Geodetic Survey took up the task of charting the coast line of Alaska, 

on which it has been actively engaged ever since. The magnitude of this task is 

shown by the fact that the length of the coast line exceeds 20,000 miles. Other 

Government vessels, such as those of the Revenue-Marine Service, Fish Commission, 

and Navy, have at various times made contributions to the knowledge of Alaskan 

coastwise navigation. The results of all of these surveys are embodied in the charts 

and coast pilots published by the Coast and Geodetic Survey.

Prior to the transfer in 1867, little was known of the interior of Alaska. The 

Russians had ascended the Yukon for 1,000 miles and the Kuskokwim for 500 

miles; had mapped the lower stretches of the Stikine; had ascended the Sushitna a 

short distance, and had made an abortive attempt to explore the Copper River. 

They were also familiar with the Alaska Peninsula and the Iliamna Lake region. 

Following the routes which had been marked out by such explorers as Franklin 

and Mackenzie, the Hudson Bay Company traders had reached the Mackenzie 

River, and in the middle of the nineteenth century crossed to the Yukon waters. 

The telegraph surveys explored the entire length of the Yukon as now defined 

and made some additions to the knowledge of the geography of the Seward 

Peninsula. Outside of these explorations, which were practically confined to the 

lower regions of some of the larger rivers, the newly acquired territory was an 

unknown land.

On October 18, 1867, the Russian flag was lowered from the flagstaff in front 

of the governor's residence at Sitka and the United States flag hoisted amidst the 

booming of cannon. This was the act of formal transfer by which Russian 

America became Alaska and a possession of the United States. At a number of 

points in southeastern Alaska and Kodiak extensive barracks were erected and 

occupied by United States troops, while an army officer represented the Federal 

Government. But ten years later all troops were withdrawn and for a number 

of years the country was governed by a naval officer stationed at Sitka. Then 

even this control lapsed, and Alaska was left for a time in the anomalous position
120 GEOGKAPHY AND GEOLOGY OF ALASKA.

of being without either military or civil government. Finally, in 1884, the first 

civil code for Alaska was enacted, and this has been modified from time to time 

by Congressional statute. Though Alaska has been in possession of the United 

States for upward of a third of a century and has a population of 62,000, it has 

not yet been granted even a Territorial form of government, being still to all 

intents and purposes a colony.

As soon as Alaska was transferred to the United States the Coast Survey 

began to gather notes on its geography, and since has been steaduV engaged in 

charting the shore line and compiling information valuable to navigation. Notable 

among the first officers of the Coast Survey to investigate Alaska are Prof. George 

Davidson and Dr. William H. Dall. Mr. Marcus Baker assisted Doctor Dall in 

this work for several years. Ho later took up the cartographic study of Alaska, 

and in 1900 made an important contribution to the knowledge of the Territory by 

his Geographic Dictionary of Alaska.

Many of the reconnaissance surveys of the coast line were made by naval 

officers attached to naval or Coast Survey vessels. Much was added to the 

knowledge of the coast geography by the cruises of the vessels of the RevenueMarine Service. Besides these surveys, other Government investigation led to 

reports on sea fisheries, fur trade, and resources in general, but it is not within 

the province of this paper to make mention of all of these.

Americans were quick to seize the opportunity for trade which the resources 

of Alaska offered. The interests of the Russian-American Company were purchased 

by a strong corporation, and other ventures were made by individual merchants. 

In 1869 a steamboat was first used on the Yukon for trading purposes. During 

the -succeeding decade several posts were established on the lower Yukon, which 

were annually visited by a steamer making one trip each season from the mouth 

of the river.

When Alaska first passed into the possession of the United States, little 

attempt was made to explore the interior. In 1869 Capt. C. W. Raymond, II. S. 

Army, was sent up the Yukon to determine the approximate position of the 

international boundary, and thus settle the conflicting interests of American and 

British traders. The results of the expedition were published in the form of a 

report, giving data in regard to natives and fur trade, and accompanied by a 

map of the lower Yukon which was an improvement on that of the telegraph 

survey, inasmuch as it included several points whose latitudes Raymond had fixed 

by astronomic observation.

The names of a small group of pioneer traders who some time in the early 

seventies entered the Yukon basin via the Hudson Bay Company route from the 

Mackenzie are known throughout Alaska. Conspicuous among these were Jack 

McQuesten, Arthur Harper, Fred Mayo, Fred Hart, Joe Ladue, and Frank Densmore. 

These men made many hazardous journeys without any of the aids of the modern 

explorer, dependent simply on their own resources. They left but few records of 

these journeys, but we know that Harper visited the White and Tanana, McQuesten 

the Koyukuk, and Frank Densmore the Kuskokwim; and the knowledge obtained by 

them entirely through their own efforts or through their intercourse with the natives
AMERICAN OCCUPATION. 121

was later in part embodied in maps of Alaska and in part preserved by word of 

month, and when the prospectors descended the Yukon, in the eighties, it proved of 

great assistance to them.

Gold was reported on the Yukon as early as the telegraph survey of 1867, but 

does not seem to have been found in workable quantities for many years later. Just 

when the first systematic prospecting was done is somewhat uncertain, but it is 

known that some time between 1873 and 1878 George Holt made his way inland over 

the Chilkoot Pass and descended the Lewes River. By some reports he is said to 

have descended the river below Fort Yukon at this time. It seems certain, however, 

whatever the date of his journey, that this was the first systematic attempt at 

prospecting' on the Yukon.

The Chilkoot Indians, fearing that their lucrative trade with the interior 

natives would be interfered with, were strongly opposed to allowing white men to 

cross the coast mountains by their trading route over the Chilkoot Pass. Through 

the intervention of Captain Beardslee, who commanded the U. S. S. Jamestown, this 

opposition was at length withdrawn, and in 1880 a party of 16 miners, under the 

leadership of Edmund Bean, crossed the Chilkoot Pass and descended the Lewes as 

far as the Teslin. These were followed by others who in the next few years 

traversed the entire length of the Lewes and the Yukon. It was not, however, 

until 1885 and 1886 that important finds of gold were made.

In 1879 Mr. John Muir and Rev. S. Hall Young visited Muir Glacier and 

explored Glacier Bay. They were the first white men to examine the bay, though 

it had been seen in 1877 by Lieut. C. S. A. Wood, while making some explorations 

in the Fairweather Mountains in company with some native hunters. Muir's 

published descriptions of the wonders of Alaskan scenery drew much public notice 

and led in later years to the development of a favorite tourist route through 

southeastern Alaska.

The most notable contribution to the knowledge of the geography and resources 

of Alaska was made by Ivan Petrof, an agent of the Tenth Census, who had long 

been a resident of the territory. He spent two years in traveling along the coast 

and on the lower Yukon and Kuskokwim, his familiarity with the native tribes and 

the Russian inhabitants enabling him to obtain much valuable data regarding regions 

not visited by him. His results and those of the several other experienced men who 

were employed in this work were compiled by Petrof in an admirable report and 

published by the Census Office. His general map of Alaska which accompanied 

this repoi't, though largely based on the statemer i of natives and traders, was 

remarkably accurate in delineating the general f .tures of the geography. He 

seems to have been the first man to have a clear conception of the distribution of 

the mountain ranges in Alaska. In judging Petrof's geography, it must be 

remembered that outside of rough traverses of the Yukon and the lower Kuskokwim the interior of Alaska was known only through the reports of a few traders.

The Indian route to the headwaters of the Yukon had been in use by prospectors 

for at least two years when Lieut. Frederick Schwatka traversed it in 1883. He 

crossed the Chilkoot Pass (called by him Perrier Pass) with a small party, and 

built a raft at the headwaters of the Lewes and continued down the river in this
122 GEOGRAPHY AND GEOLOGY OF ALASKA.

unmanageable craft, running the various rapids," to Fort Selkirk at the junction of 

the Pelly and Lewes. From this point on he was traversing a river which had been 

explored by the Western Union Telegraph agents and was already occupied by the 

fur traders. Schwatka continued his trip to Fort Yukon and thence to the sea. 

To Charles W. Homan, who accompanied Schwatka as topographer and made sketch 

surveys throughout the entire journey, correcting them by observations for latitude, 

belongs the credit of having made the first actual survey of the Yukon and Lewes 

rivers. Crude as it was, it has only in very recent years been superseded by 

better work. Schwatka's rather spectacular account of his trip down Alaska's 

great river, a journey which had been made by many others, did much to rouse 

public interest in this far away region, and in the course of the following decade a 

number of exploring parties were sent out.

During the years 1881-1883 a meteorological and magnetic station, in charge of 

Lieut. P. H. Ray, was maintained at Point Barrow by the United States Signal 

Service. No explorations or surveys of any importance were attempted.

Dr. Arthur Krause of the Geographical Society of Bremen, Germany, in 1881, 

made a journey from the coast at Lynn Canal into the Chilkoot River basin. He 

subsequently published a map which for more than ten years was the basis for all 

other maps of the region visited by him.

In 1884 Lieut. W. R. Abercrombie, U. S. Army, was detailed to make an 

exploration of the Copper River. He ascended it a short distance, but his expedition 

may be looked upon as an entire failure. This work was taken up again in the 

following year by Lieut. Henry T. Alien, who made one of the most remarkable 

journeys in the annals of Alaskan explorations. Alien, with four men, landed at the 

mouth of the Copper River in March, 1885, and made his way up that stream by 

boat and sled for about 300 miles; then crossed to the Tanana by way of the Suslota 

Pass, and securing another boat from the natives, continued his journey to the 

mouth of the Tanana. During this part of the journey the party was dependent 

entirely upon the country for food, and were in a half-starved condition when they 

reached the Yukon about the end of June. With indefatigable energy Alien then, 

with one companion, crossed to the Koj'ukuk from near the mouth of the Melozi 

River, and explored it almost from the Arctic Circle to its junction with the Yukon. 

Crossing by portage from the lower Yukon to Norton Sound, he made his way to 

St. Michael, whence he returned by steamer to the United States. No man through 

his own explorations has added more to a geographic knowledge of the interior of 

Alaska than Lieutenant Alien. Throughout his journey he made careful sketch 

surveys and noted all facts which came within his observation; and within one 

season he made maps of three of the larger rivers of the Territory, which, until 

accurate surveys were made twelve years later, were the basis of all maps. His 

reports are the work of a careful, painstaking observer, who did his utmost to gain 

all the information possible.

During the years 1883 to 1886 extensive explorations were made by officers of 

the Navy and of the Revenue-Marine Service along the rivers tributary to Kotzebue

a- Schwatka portaged his outfit around Miles Canyon and White Horse Rapids. The raft was allowed to drift through 

and was caught below.
AMERICAN OCCUPATION. 123

Sound. These led to a more general knowledge of this remote part of Alaska than 

of parts which were far more accessible.

In 1883 Lieut. George M. Stoney, who was sent to the coast of northeastern 

Siberia on the revenue steamer Conjoin to distribute presents to the natives who had 

aided the Jeannette relief expedition, examined the vicinity of Kotzebue Sound, and 

with the aid of some natives explored the delta of the Kobuk River, which Simpson 

had learned of in 1850. Having interested the Navy Department in these 

explorations, Stoney returned in the following year, and with the aid of a steam 

cutter and a native boat managed to ascend the Kobuk to the mouth of the 

Soolukpowaktoark River, and continued up that stream to its source in Walker 

Lake. In the same year Ensign Purcell of the Stoney party explored Selawik Lake.

A third trip into this region was made by Stoney in 1886, this time accompanied 

by a large and well-equipped party, which established winter quarters on the 

Kobuk, about 250 miles from its mouth, and spent the winter in extensive explorations. Stoney explored the headwaters of the Noatak and of the Alatna, the 

latter a tributary of the Koyukuk, and reached the head of the Selawik River, 

south of the Kobuk, and Chandler Lake, in which the Colville River has its source. 

Some of Stoney's officers made trips into the interior. Ensign Reed led a party 

from the winter camp to the Noatak River, and Assistant Engineer Zane reached 

the Yukon by way of the Pah and Koyukuk rivers; but the most noteworthy 

trip was that made to Point Barrow by Ensign W. L. Howard. He left the winter 

camp in April with two white men and two natives and proceeded northeast across 

the Noatak to the valley of the Colville, followed this downstream in company 

with a party of natives for about 20 miles, and then crossed to the headwaters 

of Chipp River. Here he discarded the dog teams used up to this point for 

transporting his supplies, and descended the Chipp River to the coast in native 

skin boats, arriving at Point Barrow on July 15, being the tirst white man to 

cross northern Alaska. The results of-the expedition were a fairly accurate survey of the Kobuk Valley and sketch maps of the Selawik, upper Colville, upper 

Noatak, and Alatna rivers. Stoney's was the first attempt at instrumental surveys 

in the interior of Alaska.

In 1884 Lieut. John C. Cantwell, of the Revenue-Marine Service, explored the 

Kobuk as far as the mouth of the Black River. In the following year Cantwell 

succeeded, by using at first a steam launch and afterwards a skin boat, in reaching Walker Lake, near the head of the Kobuk. He was the first white man to 

reach the upper Kobuk, and, considering the conditions under which the trip was 

made, prepared a very creditable map of the river. Mr. Charles H. Townsend, 

of the United States Fish Commission, accompanied the party as naturalist. 

Another officer of the Revenue-Marine Service, S. B. McLenigan, made an exploration in this region in 1885. With one companion he ascended the Noatak River 

about 300 miles in a native skin boat, carrying out his instructions in the face of 

many obstacles and maintaining a sketch survey throughout his journey. His 

map has not yet been superseded by more accurate surveys.

Mount St. Elias has long been a subject of great popular interest, both because 

of its altitude, it being at one time considered the highest peak on the continent,
124 GEOGRAPHY AND GEOLOGY OF ALASKA.

and because it was the first point sighted by a white man on the mainland of 

Alaska. Bering, who discovered and named it, knew it only as a distant peak 

which loomed above the clouds, for ho made no attempt to get near it. The 

mountain was also noted by Cook, Dixon. and Vancouver during their explorations of the coast line. In 1786 La Porouse, while cruising along the coast, saw 

Mount St. Elias. and Dagelet, his astronomer, calculated its altitude at 12,672 feet. 

Five years later Malaspina entered Yakutat Bay and surveyed Disenchantment 

Bay, its inland extension, which ho hopod would prove to bo a northeast passage. 

His determination of the altitude of the mountain as 17,851 feet came remarkably 

near the truth, considering the adverse conditions under which it was made. In 

1737 Sir Edward Belcher visited Yakutat Bay in H. M. S. Sulphur. Tebenkof's 

Atlas, published in 1852, gives the altitude of the mountain as 17,000 feet. la 

1874 Dall and Baker, while cruising along tho coast, made a rough triangulation 

and reported the altitude of tho mountain at over 19,000 feet.

It was nearly a century and a half after Bering's discovery before any attempt 

was made to ascend the mountain or even to approach its base. In 1886 Frederick 

Schwatka, with Prof. William Libbey and Lieut. H. W. Seton-Karr, led an expedition, which was supported by the New York Times, to make the ascent of the 

mountain. So little was known of the conditions of travel that the party was 

foredoomed to disaster. Schwatka and Seton-Karr, with a small party, reached 

a point about 20 miles inland and obtained considerable geographical information 

which was of great use to the subsequent explorers. Two years later an altitude of 

11,400 feet was attained by a party consisting of W. H. Topham, Edwin Topham, 

and George Broca, Englishmen, and William Williams, an American. A third 

attempt was made in 1890 by I. C. Russell and Mark B. Karr, with six camp 

hands, nnder the joint auspices of the National Geographic Society and the United 

States Geological Survey, which, though unsuccessful, resulted in some important 

contributions to the geographic knowledge of the region. Russell and Karr would 

undoubtedly have reached the top had not a severe storm forced them to retreat 

after waiting four days in rude shelters in snow banks on the upper slopes of 

the mountain without fuel and almost without food. Russell, nothing daunted by 

this experience, in 1891 again essayed the ascent under the same auspices. During 

this attempt he succeeded in reaching a height of 14,500 feet, but was again forced 

to return by severe storms. The results of Russell's two expeditions were a large 

amount of data in regard to tho glacial history of the region and a fairly accurate 

map of the slope of the mountain. His determination of 18,100 feet as its height 

proved to be remarkably accurate, if one takes into account the conditions with 

which he had to contend. The Coast Survey triangulation of the following year 

shows tho elevation to be 18,024.

Tho summit of St. Elias was reached by an Italian, Prince Luigi, who followed 

the route which Russell had explored and very largely adopted the methods which 

Russell had recommended. Luigi, in 1897, landed at Yakutat Bay, and with a 

large, thoroughly equipped expedition made his way across the 40 miles of snow 

and ice between the coast and the base of the mountain. In his ascent he practically followed Russell's route, reaching the summit July 31, rive weeks after 

leaving tidewater. Prince Luigi's expedition was carefully planned, and he showed
AMERICAN OCCUPATION. 125

himself a capable leader as well as an experienced mountaineer. The report" of 

the expedition contains much that is of geographic interest, but is chiefly valuable 

as a contribution to the literature of mountaineering.

The location of the international boundary on the Yukon became a question 

of importance after the discovery of rich gold placers near it. The Canadians were 

first in the field. In 1888 William Ogilvie and George M. Dawson made surveys 

of the route from the head of Lynn Canal, in southeastern Alaska, to the mouth 

of the Lewes River. Ogilvie in the following year extended his surveys down 

the Yukon to the international boundary, and in 1890 continued his exploration 

to the head of the Porcupine, which had been surveyed in the previous year by 

R. G. McConnell, of the Canadian Survey.

Meanwhile the United States Coast and Geodetic Survey had dispatched two 

parties to the boundary. One of these, under J. E. McGrath, established an 

astronomic station near the boundary on the Yukon, and the other, under 

J. H. Turner, made a similar station where the boundary crossed the Porcupine. In 

connection with this work Turner's party in 1890 made a winter trip with dog teams 

from the camp on the Porcupine to the Arctic Ocean, following as nearly as possible 

the one hundred and forty-first meridian. This was the second time that northern 

Alaska was crossed by white men, the first being three years before by Ensign 

Howard. McGrath and Turner's surveys were limited to very small areas, but are 

of general geographic interest, as they represent the first geodetic surveys in the 

interior of Alaska. Besides the work to which they had been specially detailed, they 

also kept meteorologic records and made corrections from their route traverses in 

the existing maps of the Yukon. Prof. I. C. Russell, of the United States Geological Survey, accompanied McGrath to the boundary from the mouth of the river, 

and thence came to the coast with a party of prospectors by way of Lewes River 

and the Chilkoot Pass.

In 1890 an expedition was sent out by Frank Leslie's Weekly for explorations 

in Alaska. The writer has been unable to discover any account of the work of this 

party. It apparently left the coast at Pyramid Harbor, ascended the Chilkat River, 

and after crossing the divide explored Lake Kusawa. There the party divided and 

A. B. Schanz and S. J. W7 ells descended to the Yukon, while E. J. Glave and Jack 

Dalton crossed the divide to Alsek waters, and followed the Alsek River to the coast. 

Later in the season Wells made a trip down the Tanana, and Schanz is said to have 

visited lakes Clark and Iliarnna during the following winter. Glave and Dalton's 

exploration of the Alsek was a daring piece of work, as its character at that time 

was entirely unknown. Its course through the St. Elias Range has not even yet 

been surveyed.

In 1891 Schwatka made his third trip to Alaska. Schwatka, C. WT illard Hayes, 

of the United States Geological Survey, and Mark Russell, a prospector, ascended 

the Taku River, crossed the divide to Teslin Lake, and in folding canoes, which had 

been transported across the pass by natives, went downstream to the Lewes River 

and continued to Fort Selkirk, on the Yukon. Crossing overland to the White

«It is somewhat surprising that in the account of this expedition it should be gravely stated that the barometric 

determination of the altitude of Mount St. Elias of 18,090 feet should be regarded as more accurate than the previous 

instrumental determinations by Russell. As a matter of fact, J. E. McGrath, of U. S. Coast and Geodetic Survey in 

1892, had fixed the height of Mount St. Elias at 18,024 feet by triangulation.

17211 No. 45 06 9
126 GEOGRAPHY AND GEOLOGY OF ALASKA.

River, near the point where it is intersected by the international boundary, they 

then continued up the White to its source; and though they were deserted by all of 

their Indian packers, the three white men of the party went on through Skolai Pass, 

and, after reaching navigable waters on the Nizina, built a boat and continued 

down to the Copper River. Doctor Hayes's report and map, which are based on a 

foot traverse, are remarkably complete and accurate considering the exceedingly 

trying conditions under which the field observations were made, and give much 

geologic and geographic information about a region which up to the time of its 

publication was practically unknown.

In that same year Glave (who later lost his life on the Congo) and Dalton made 

a second trip into the Alsek basin. This time they are said to have extended their 

journey westward to the White River basin, but the map accompanying Glave's 

published account is very inaccurate. The exploit is of interest chiefly because it 

was the first time in the history of the country that horses were used on an extended 

journey.

Congress, in 1895, tardily recognized the importance of an investigation of the 

mineral resources of Alaska, and by a small appropriation enabled the Geological 

Survey to send its first party to the north. Dr. George F. Becker, aided by C. W. 

Purington, made a preliminary investigation of the gold deposits, and W. H. Dall 

studied the coal deposits of the Pacific coastal belt. The following year J. E. Spurr, 

with H. B. Goodrich and F. C. Schrader, descended the Yukon and visited the more 

important placers of Alaska and did some topographic as well as geologic mapping.

Even thirty years after its accession the mass of the public was still almost 

entirely ignorant of the geography, resources, or climate of Alaska. Well-informed 

people regarded it as a region of perpetual snow and ice, the land of the fur trader, 

Indian, and Eskimo. A great change was wrought by George W. Carmack's 

discovery of gold on the Klondike River, in Yukon Territory, during the summer of 

1896. This event led to the development of the famous Klondike placer field, which 

in one year brought more than 50,000 people into Alaska and the adjacent portions 

of Canadian territory, and made the name Klondike a household word in every 

civilized country on the globe. Hardly had the Klondike excitement subsided 

somewhat when the discovery of the Nome placer fields in 1898 again attracted the 

attention of the world to Alaska, and a second exodus to this northern region took 

place.

Of the thousands who entered the Yukon basin during the first years of the gold 

excitement, but a small percentage had any conception of the difficulties with which 

they would be confronted, and still less had any previous training which fitted them 

for the work they had so rashly undertaken. Hundreds toiled over the Coast Range 

passes and made the mad dash to reach the Eldorado their fancies had painted, but, 

discouraged at the outlook, continued down the Yukon to its mouth, having hardly 

been out of sight of its banks. The more venturesome prospector, however, found 

no risk too hazardous, no difficulty too great, and now there is hardly a stream which 

has not been panned by him, and hardly a forest which has not resounded to the 

blows of his ax. Evidences of his presence are to bo found from the almost tropical 

jungles of southeastern Alaska to the barren grounds of the north which skirt the 

Arctic Ocean. While the prospectors have traveled far and wide in Alaska, they
AMERICAN OCCUPATION. 127

have as a class added little to the knowledge of its geography. As a rule they follow 

but two purposes, one to find gold and the other to get through the country. The 

information obtained by them is seldom exact, even when available, for their conception of where they have been is often as vague as their ideas as to where they are 

going. Though their contribution to geographic knowledge is small, these pioneer 

prospectors, at the expense of hard toil and suffering, if not of their lives, have 

blazed the way for the settler, miner, and surveyor.

The public interest aroused in Alaska by the finding of valuable placer mines 

in adjacent territory led to a demand for more definite information, and money 

was appropriated for investigation in Alaska under various bureaus of the Federal 

Government. The Coast and Geodetic Survey was enabled to expand its Alaskan 

surveys, which had been carried on ever since the purchase of the Territory. The 

Army established military posts to preserve order and to extend relief to the many 

ill-equipped and inexperienced Argonauts. It also built trails and telegraph lines, 

which were to become of immeasurable advantage to Alaska, and even attempted 

some explorations and surveys, but these were only partially successful.

When in 1898 the Geological Survey 0 began its systematic surveys and explorations in the interior of Alaska the problems which confronted it were not easy. 

The public demanded the immediate publication of maps of unexplored or only 

partially explored regions. Such maps would have far greater value if they 

could be furnished while the excitement was at its height, so there was not 

opportunity for extensive areal mapping. The problem was to make surveys 

of the main routes of travel, which were chiefly confined to the larger rivers, 

and to include with these as wide areas as possible. The first season's work 

resulted in about 3,000 miles of instrumental traverses, with reconnaissance maps 

of an area of nearly 30,000 square miles, besides more accurate survey of about 

2,000 square miles. These traverses were largely confined to the more important 

rivers. The work had to be planned with a very incomplete knowledge of the 

geography and of the climate and other conditions of travel of the region, and 

all supplies and equipment had to be transported from Puget Sound ports. 

After landing in Alaska the parties were entirely dependent on their own 

resources for transportation. The first year they made their way by following 

the waterways in canoes, which were carried on the backs of the men at 

portages, but after some knowledge of the country was gained it was found that 

horses could be used to advantage for the transportation of supplies.

The general scheme of operations for the first year included exploration of 

the Kuskokwim, the Sushitna, and the Copper rivers, as all three of these 

streams offered possible routes into the interior. The Copper River work was 

carried on by members of the Geological Survey under the auspices of the War 

Department, which organized two expeditions for the purpose, one under Capt. 

Edwin F. Glenn and the other under Capt. William R. Abercrombie.

Glenn, with a small detachment provided with pack horses, left the coast 

at Cook Inlet and made his way northward along the Matanuska, crossed the

a Between 1898 and 1902 the following officers of the Geological Survey took part in the Alaskan work: E. C. Barnard, 

Alfred H. Brooks, Arthur J. Collier, George H. Eldridge, T. G. Gerdine, W. C. Mendenhall, Robert Muldrow, W. J. Peters 

W. S. Post, D. L. Reaburn, G. B. Richardson, F. C. Schrader, Arthur C. Spencer, J. E. Spurr, and D. C. Witherspoon.
128 GEOGKAPHY AND GEOLOGY OP ALASKA.

Copper River Plateau, and descended the Delta River to the Tanana, whence he 

returned to the coast by the same route. No surveys whatever were made by 

Glenn, but, fortunately, Mendenhall, of the Geological Survey, who had been 

detailed to his party, was enabled to carry on a route traverse throughout the 

journey. Mendonhall's map and report formed a valuable contribution to the 

knowledge of the geography of Alaska. At the Tanana Lieut. J. C. Castner was 

detached from Glenn's party to continue the exploration to Circle, on the Yukon. 

With two men he crossed the Tanana and attempted to make his way up Volkmar 

River, but the lateness of the season made the plan impracticable. After losing 

both their horses the three attempted to return to the Tanana on a raft. Their 

raft was wrecked and everything lost, including their shoes; they reached the 

Tanana half dead with hunger and exposure, and were fortunate enough to find 

some friendly Indians. The journey which had cost so much suffering and 

privation yielded practically nothing of value. Some minor explorations were 

carried on by Lieut. H. G. Learnard and Sergt. William Yanert, also of 

Glenn's party.

The second army expedition, under Captain Abercrombie, landed at Valdez, on 

Prince William Sound. The heavy snowfall prevented an early start, but eventually 

the entire party, including horses, made its way inland by the Valdez Glacier route, 

which that year was used by hundreds of prospectors. After reaching the Copper, 

Captain Abercrombie left the party for a hurried trip to the Mentasta Pass along the 

trail established by prospectors. Lieut. P. G. Lowe, following a similar route, 

made his way to Fortymile, and returned to the coast byway of the Lewes River and 

the White Pass Railway. The rest of the party, under the leadership of F. C. 

Schrader, of the Geological Survey, did some very creditable work in making surveys and investigations in the lower part of the Copper River basin.

The exploration of the Sushitna was undertaken by Eldridge and Muldrow, of 

the Geological Survey, with five men. They made their way up the river from 

Cook Inlet, dragging their supplies in canoes against the swift current. At Jack 

River the boats were left, and with packs on their backs the party pushed on to the 

Cantwell River, confluent to the Tanana, but at this point were forced to turn back 

by the failure of provisions, and reached their boats in a half-starved condition. 

Surveys were made throughout the journey, and the position and height of Mount 

McKinley were determined.

The longest exploration of 1898 was that made by Spurr and Post, who ascended 

the Yentna, the left fork of the Sushitna, and portaging to Kuskokwim waters, 

descended the latter river to its mouth, and returned to Cook Inlet by a route which 

crossed the Alaska Peninsula.

The same year the two most important southern branches of the Yukon the 

Tanana and White rivers were surveyed. A party led by Peters and Brooks 

crossed the Chilkoot Pass and went inland on the snow and ice to Lake Marsh, 

where, after delaying until the ice broke up, they embarked in canoes for the White 

River, at which point the survej's began. The ascent of the river was made by 

dragging the canoes against the rushing current. Six weeks of this toilsome task in 

the glacial waters brought the party near the head of Snag River, a northern tribu-
AMERICAN OCCUPATION. 129

tary of the White, whence the Tanana was reached by portage, after which the 

downstream trip to the Yukon was comparatively easy. Exploratory surveys of 

about 10,000 square miles were made by this party. The same year Barnard, following a similar route from the coast to the Yukon, made a survey of about 2,000 

square miles in the Fortymile River basin.

In 1899 Peters and Brooks continued their explorations by a survey extending 

westward from Lynn Canal along the northern base of the St. Elias Range to the 

headwaters of the White and Tanana rivers and northward to the Yukon at Fortymile. The journey was made with horses, only five out of the original fifteen 

reaching the Yukon.

In this year the work of exploring the great waterways was extended north of 

the Yukon to the Koyukuk, which was mapped by Schrader and Gerdine. Leaving 

Fort Yukon in canoes, they ascended the Chandlar River, and after making a 16-mile 

portage reached Koyukuk waters and followed them to the Yukon.

In the fall Schrader and Brooks met at St. Michael and after the close of the 

work decided to visit the newly discovered placers at Nome. The investigations, 

while very hastily made, had their value, because they enabled the Geological Survey 

to publish a report containing authentic information before the exodus to the new 

gold fields, which took place in the following spring.

The great demand for maps of important mining districts, in 1900, forced the 

Geological Survey to postpone further explorations. One party, under the leadership of Schrader, Gerdine, and Spencer, mapped a large area in the Copper River 

basin, both geologically and topographically, while Barnard, Brooks, Peters, and 

Mendenhall did similar work in Seward Peninsula.

In 1901 the work in northern Alaska was resumed, and a network of surveys 

completed connecting the Yukon, Koyukuk, and Kobuk rivers, the Arctic Ocean 

and Kotzebue Sound. Schrader and Peters made a trip which included a journey 

the entire length of Alaska from its southernmost limit to Point Barrow. Starting 

in winter, they traveled to the Koyukuk with dog teams, thence ascended one of 

the north forks of that stream with canoes, crossed to a branch of the Colville, and 

followed it to its mouth. They then skirted the coast westward to Point Barrow 

and finally southward to Cape Lisburne, where they were so fortunate as to find a 

steamer. In course of their journey they traversed the Endicott Mountains, and 

brought back the first authentic information in regard to this great range. Theirs 

was probably the most notable exploration which has been made by the Geological 

Survey. In the same year Mendenhall and Reaburn also made surveys and explorations in this northern region. They reached the mouth of Dall River on the Yukon 

in June, ascended that stream in canoes, and then by an 18-mile portage reached 

Koyukuk waters. They descended the Koyukuk to the mouth of Alatna River, 

which they ascended for about 100 miles, and then made a second portage which 

brought them to the Kobuk River, which they followed to its mouth. This expedition is of particular interest in that it made the first instrumental survey from 

the Yukon to tide water. The topographic survey was begun at Fort Yukon and 

carried through to Kotzebue Sound. It established an altitude of 500 feet for the 

river at Fort Yukon, which is probably approximately correct.
130 GEOGRAPHY AND GEOLOGY OF ALASKA.

During the same season Brooks was engaged in geologic studies in southeastern 

Alaska, and Gerdine, Collier, and Witherspoon did areal mapping in the Seward 

Peninsula.

The work for 1902 was planned to include an exploration of the largest 

unexplored area in southern Alaska, and the running of a traverse to the Yukon 

which should connect the previous surveys of the Sushitna, Kuskokwim, and 

Tanana. To this end a party led by Brooks and Reaburn extended a survey 

northwest from Cook Inlet through the Alaska Range, and bending northeast 

passed close to the base of Mount McKinley and on to the Cantwell Rh*er, 

whence they took a northwesterly route across the Tanana to Rampart on the 

Yukon. During the same season the areal mapping of the Copper River basin was 

concluded by parties led liy Schrader, Grerdine, Mendenhall, and Witherspoon, 

while Collier studied the geology of the Yukon, and Peters made a detailed 

topographic survey near Juneau.

Of the twenty or more parties which the Geological Survey has sent to 

Alaska, hardly a single one has failed to execute the work allotted to it. This 

is largely because those who were intrusted with their leadership were specialty 

fitted, by nature as well as by experience and training, for the undertaking. 

The parties have usually been made up of a few carefully chosen men, and the 

physical work and discomforts, as well as hardships, have been shared by leaders 

and men alike. In connection with the topographic surveys geologic investigations hav.e gone hand in hand; in some instances somewhat detailed studies having 

been undertaken, while in others the work was purely of a preliminary character 

(see fig. 3).

The topographic and geologic mapping carried on in various parts of Alaska 

since the organization of systematic surveys has resulted in the completion 

of a preliminary map of the Copper River basin and of the Seward Peninsula. 

A considerable area has also been surveyed in the region lying between the 

Yukon and the Tanana. A more detailed map of a part of the Juneau mining 

district has been finished, which is to serve as the basis for geologic studies 

during the coming season.

Besides the geologic work already mentioned, it is planned to make a reconnaissance of the oil fields of the Pacific coast belt of Alaska, and to study the 

placer fields of both the Tanana-Yukon district and the Seward Peninsula. In 

addition to this economic work steps have been taken to make a detailed examination of some of the Tertiary and Mesozoic beds exposed along the Yukon.

Subsequent to the work done in collaboration with members of the Geological Survey in 1898, the Army continued to send out expeditions. In the following year some more or less detailed surveys were carried on in connection with 

constructing the military trail across the Chugach Mountains from Valdez. 

These operations, as well as some minor explorations, were carried on under 

direction of Captain Abercrombie. Oscar Rohn, a civilian employee of Abercrombie's party, with one companion, made a daring journey, in which he 

crossed the Wrangell Mountains to Tanana waters and then returned to Copper 

River, making a sketch map as well as geologic observations.
AMERICAN OCCUPATION. 131

Another part}', provided with horses and a large river steamer, was sent to 

Cook Inlet under command of Captain Glenn. The most notable contribution of 

this expedition to geographic knowledge of Alaska was Lieut. Joseph 8. Herron's 

exploration in the upper Kuskokwim basin. Following the general route previously traversed by Spurr and Post, Herron crossed the Alaska Range and entered 

the great lowland which lies to the northwest. Here considerable time was lost 

b}- a search for natives to act as guides, during which the early frosts killed the 

grass and the pack horses had to be abandoned. At length, with the aid of Indian 

guides, Herron's party reached the Yukon in the early winter. C. E. Griffith, a

ITS' 178' 174' 170' K.G' 102" ]Gb" 154' 150' 14G' 142" 1:!S' 134' 130' 12G' 122" 118°

FIG. 3. Map showing areas surveyed and explored Ijy United States Geological Survey, 1898 to 1903.

topographer of Glenn's command, led a small party from Knik Arm, Cook Inlet, 

to Eagle, on the Yukon. His route lay partly through the region previously 

explored by Glenn and Mendenhall, and partly over the well-traveled trail which 

leads from Valdez to Eagle. George W. Van Schoonhoven, also of Glenn's party, 

attempted, with a full equipment of horses, to reach the Tanana from Cook Inlet. 

He first followed the route survej'ed by Eldridge and Muldrow in the previous 

year, but turned back at the Cantwell, reporting the route impassable. In this 

he was mistaken, for Brooks and Reaburn in 1902 crossed the Cantwell where he 

turned back, and continued through to the Tanana without serious difficulty.
132 GEOGRAPHY AND GEOLOGY OF ALASKA.

During the past two years the Signal Corps of the Army has been pushing the 

\vork of constructing telegraph lines, and as a result has connected by wire the 

most important" points, both inland and on the coast. Reconnaissance surveys 

have to a certain extent been carried on subservient and preliminary to the construction of the telegraph lines.

CONCLUSION.

Over a century and a half has elapsed since Bering and Chirikof first sighted 

the mainland of what is now known as Alaska, and during this time geographical 

discoveries have been steadily going on within its borders. First came the Russian 

trader, who in the course of his marauding voyage made his way step by step along 

the Aleutian Islands to the mainland. Then Cook and Vancouver and other navigators carried on systematic surveys of its shore line. With the organization of 

the Russian-American Company, in 1799, a new epoch of permanent settlements 

and slight but important explorations was introduced, which continued until the 

transfer of Alaska to the United States. During this time the English contributed 

much toward a knowledge of Arctic Alaska through the surveys made by their 

Franklin relief expeditions. Mackenzie's famous journeys across the continent to 

the Arctic Ocean pointed out the way to lucrative fur trade to the English, and 

brought them to Alaska from the east. Their explorations on the upper Yukon 

were linked with those of the Russians below by the journey of Kennicott, Dall, 

and their associates of the telegraph survey.

After Alaska became a United States possession there was a lull in explorations within its borders, though the Coast Survey began to chart the coast line. 

Except for Raymond's trip up the Yukon and the efforts of Petrof and of fur traders 

and prospectors no attempt was made at an extension of geographic knowledge in 

the interior until Schwatka made his trip down the Lewes and Yukon. This was 

followed by the less generally known though no less important explorations in the 

northern part by officers of the Navy, the Revenue-Marine Service, and the Coast 

Survey. Since Alaska attracted public notice through its placer gold resources 

important and extensive surveys and explorations have been carried on by the 

Geological Survey.

Alaskaii surveys and explorations have never been and never will be easy. 

Throughout its history the geographic investigation has been a tale of hardship and 

suffering and not infrequently of death. Let those who are not personally familiar 

with the character of the difficulties not judge it too harshly. If the results have 

not always been commensurate with the expenditure of money, time, and even of 

human life, it should be remembered that the conditions of travel in the past have 

not been so favorable to the explorer as in some of the more temperate regions. 

The task is not yet complete. Reconnaissance surveys have been effected in but 

one-fifth of the territory, leaving large areas which are still practically unexplored.

a Nome, the Yukon, Tanana, and Copper River valleys are now connected with Dawson and with Valdez by 

telegraph. Dawson has outside telegraph connections through Canadian territory with the United States and to the 

coast at Skagway, Alaska. Skagway, Seward, and Valdez, all on the Pacific coast, are connected by cable with Seattle.
GEOGRAPHY ASD GEOLOGY OF ALASKA. 133

CLIMATE.

By CLEVELAND ABBE, Jr. 

INTRODUCTION.

No discussion of the geography of a region is complete without some mention 

of the climate, for while on one hand climate is determined in a large measure by 

the relief of the earth's surface, on the other hand the surface features are the 

resultants of the atmospheric forces working upon the rocks of the earth's crust. 

The interest in climate does not end here, however, for the climatic conditions, as 

much as the topography and geographic position, determine the occupation and 

development of a region by man. Temperature and precipitation are as important 

as geographic features and natural resources. The relation of climate to animal and 

vegetable life, and hence to man's occupation of any portion of the earth's surface, 

is too evident to need special mention.

The following pages will be chiefly devoted to the climatic problems which are 

of special import to the settler, prospector, and miner, but it is hoped that the data 

compiled and the conclusions reached may not be without interest to the student of 

North American meteorology.

Ignorance of Alaska's varied climates has been widespread and has led to not a 

few blunders, both in the administration of the territory and also in plans for its 

investigation and development. Had accurate information been in the possession 

of the public at the time of its purchase, concerning its varied climatic provinces, 

which in a large measure control its animal and vegetable life and conditions of 

travel, a different feeling would have prevailed concerning that much-criticised 

transaction. The subsequent development of its resources might have been accomplished with a far smaller expenditure of time, money, and even of human life.

Though Alaska has been in our possession for nearly forty years, and part of 

its area has been known to whites for upward of two centuries, the mass of the 

public is profoundly ignorant of its climatic features. Even well-informed people 

still speak of it as a land of ice and snow, and there are few who realize that a part 

of its Pacific coastal province has a temperate climate.

METEOROI.OGIC OBSERVATIONS.

During the Russian occupation, except in a few instances, there seem to have 

been no systematic efforts made to record accurate meteorologic observations. The 

best records during this period were kept by the Russian missionaries at their 

mission stations, Unalaska (Iliuliuk) and Jkogmut, and by the Russian Government 

officials at Sitka. Other records of less extent were made by the many explorers, 

travelers, and traders who visited the region. After the transfer of the territory 

to the United States the surgeons at United States army posts kept meteorologic 

records in connection with the post hospitals.

In 1878 and 1879, soon after the organization of the United States Weather 

Bureau, first under the Signal Corps of the army, later as a bureau of the 

Department of Agriculture, a few first-class observing stations, together with 

several voluntary stations of lower order, were established in Alaska. Most of 

these have been located along the coast or on the neighboring islands, and records
134 GEOGRAPHY AKD GEOLOGY OF ALASKA.

of the great interior region have been dependent on the more or less incomplete 

data gathered by exploring and surveying parties and by voluntary observers, 

including traders and missionaries. The most important records from transient 

stations arc those kept by the "International Arctic Expedition" (1882-83) at 

Utkiavi on Cape Smyth, by the two Coast and Geodetic Survey parties sent out 

(1880-1891) to determine the intersections of the one hundred and forty-first 

meridian with the Yukon River, by the Western Union Telegraph Company 

Expedition (1865-1867), and by the Geological Survey exploring parties (1898-1903). 

The demand for study of the agricultural possibilities of Alaska led to the estab 

lishment in 1898 of a special Alaska division of the experiment-station service of 

the Department of Agriculture, and since that year reliable observations in the 

district have been multiplying.

SOURCES OF MATERIAL.

The observations made up to the end of 1877 have already been summarized 

by Dall and Baker, and published, together with a very full bibliography, by the 

Coast and Geodetic Survey. a The results of observations made at six United 

States army posts, from 1861 to 1871, and the continuous series of Russian and 

American observations at Sitka, from 1847 to 1874, have been summarized by C. A. 

Schott, * and published in two volumes by the Smithsonian Institution. They form 

valuable supplements to the earlier monograph by Dall and Baker.

In the following pages will be summarized the most important results of the 

observations made subsequent to the publication of Dall and Baker's work, and 

features of most interest to those concerned in the economic development of the 

country will be particularly emphasized.

The material summarized in the accompanying tables was taken from the manuscript records covering the period from 1868 to the present time, in the custody of 

the United States Weather Bureau. Thanks to the courtesy of the Chief of the 

Weather Bureau, and the chief of the records division of the Weather Bureau, 

the writer was able to consult all the records now collected by the Bureau and 

deposited in its vault. These records were made by observers who may be grouped 

in four classes post surgeons at regular United States army posts, regular Signal 

Service or Weather Bureau observers, voluntary observers supplied by the Weather 

Bureau with instruments, and members of various expeditions.

METHODS OF OBSERVATION.

The accuracy of the observations here used and the methods of making them 

may be most conveniently discussed for each of the elements.

TEMPERATURES.

The temperatures recorded by the army post surgeons were observed by means 

of standard instruments (type not known), three observations being made daily, 

7 a. m., 2 p. m., and 9 p. m. These stations seem also to have been supplied in 

some cases with self-registering maximum and minimum thermometers, but the

"Ball, W. H., and Baker, M., Pacific Coast Pilot, Coast and Islands of Alaska, Appendix I, Meteorology and Bibliography, 2d series, Washington, 1879.

SSchott, Charles A., Tables, distribution, and variations of the atmospheric temperature in the United States, etc.: 

Smithsonian Contrib. Knowl., vol. 21, No. 277, Washington, 1876, pp. 10,11,124. Tables and results of the precipitation 

of rain and snow in the United States, etc.: Ibid., vol. 24, No. 353, Washington, 1881, 2d ed., pp. 11,113.
CLIMATE, METHODS OF OBSERVATION. 135

records of such thermometers in the only case where their use was noted were so out 

of harmony with the tri-daily observations that they have not been used in this 

compilation. These observations record the temperature to two decimal places. 

Since most of the other records record temperature to the first decimal place only, 

the temperatures, as here published, have all been reduced to the nearest whole 

degree for the sake of uniformity. The maximum and minimum temperatures 

from the stations occupied by army posts represent only the maximum and minimum observed temperatures, and are indicated in the tables by (*). Concerning the 

exposure of the thermometers at army posts in Alaska, the following quotation 

from Dall and Baker is all that has been learned. They say," "The observations 

[at Sitka] recorded in the Manuscript Meteorological Register LI. S. Army were 

made in front of the hospital, which, facing southeast, fronts on Eastern Harbor. 

The instruments hung in an open latticework box of the ordinary construction for 

the reception of meteorologic instruments and at an elevation of 13^- feet above the 

level of the sea.''

The temperature observations at Signal Service or Weather Bureau stations, 

whether at a regular station or by voluntary observers, are always made with 

standardized instruments issued by the central office in Washington, and have been 

accepted as correct, so far as the instruments were concerned. The instruments 

were presumably exposed in the standard Weather Bureau instrument shelter, and 

the observing hours were, during the early years, 7 a. m., 2 p. in., 9 p. m., but for 

the records of the voluntary observers, which were made by means of self-registering 

maximum and minimum thermometers, only one observation daily, made usually at 

8 a. m., was required. In some cases, where the one or the other of the registering 

thermometers was broken, the missing extreme temperatures were supplied by 

observations at noon or at 7 a. m. When these latter observations seemed to be 

approximately true extreme temperatures they were admitted as part of the 

material for the table, but always with a note indicating at what hours they were 

made. Observations made by the voluntary observers of the Weather Bureau are 

made by means of standard instruments issued to those observers. These instruments are always accurately compared and corrected before being issued, and a 

card of corrections furnished, but in few, if any, cases is information at hand as 

to whether the proper corrections have been applied. It is believed, however, that 

all the results presented in the accompanying tables are reliable to within i° F.

METHODS OF OBSERVING PRECIPITATION.

The precipitation data obtained from the Government army posts were presumably based upon observations made with the so-called conical De Witt gage,* 

which was issued by the Army to post hospitals. This gage, which is in the 

shape of an inverted cone, was recommended c to be exposed by cutting a hole 

in a board of sufficient diameter to allow the conical gage to come down just 

flush with the upper surface of the board. Such an exposure might cause these 

gages to be classed among "shielded rain gages," and would be very favorable 

to an accurate registration of rainfall if the board with its gage were exposed

a Pacific Coast Pilot, p. 60.

!>De Witt, S., Description of the nine-inch conical rain gage: Am. Jour. Sci., New Haven, 1st ser., vol. 22, 1832, 

321-324 (fig.).

cBchott, C. A., Smithsoniaii Contrib. Knowl., vol. 24, No. 353, p. xl.

PP
136 , GEOGRAPHY AND GEOLOGY. OP ALASKA.

at a sufficient distance from surrounding objects. As to the actual exposure of 

the gages at Alaskan posts nothing is known. The rainfall was measured at army 

posts at the close of each storm, or more frequently if necessary to prevent the 

gage overflowing before it was read. Usually the time of beginning and ending of 

the rainfall was given, but only one measurement was made, namely, at the close 

of. the storm, so that the given amounts of precipitation in the records often were 

for rainfalls extending over two or three days. In some cases, however, readings 

were made at 9 a. m. daily, as well as at .the end of the storm, so that it was possible to determine the daily rainfalls more readily. The table on pages 162-165 shows 

. the mean total rainfall for each month to midnight of the last day of the mouth. 

In the original army records a rainfall extending over the last day or two of 

one month and the first day or two of the next month was often not recorded 

until the end of that rainfall. In the earlier averages, published by Schott and 

Dall, no account was taken of this overlapping of the rainfall records. In the 

present work an attempt has been made to redistribute the rainfall so that that 

portion of it falling in the preceding month should be credited to that month 

and not to the following month. This redistribution was made according to the 

following plan: When the hours of beginning and ending of rainfalls or showers 

were given in the records the total rainfall was divided by the number of hours, 

and thus the amount of rain on each day was determined. When daily readings 

we're made and no times of beginning and ending were recorded the readings were 

alwaj'S allowed to stand as they were given. From the daily rainfalls as thus 

estimated was selected the greatest of each month for entering in the table on 

pages 166-167. The redistribution of rainfall just described became of particular 

importance in calculating the maximum daily rainfall for any mouth, since the 

daily measurements of rainfall are not usualty given in the army records.

In cases of rainfall records made by voluntary or regular observers of the 

Weather Bureau, the instructions required the observer to record the rainfall every 

day, and it has not been necessary, in any case, to redistribute the rainfall among 

the days on which it did fall, or is supposed to have fallen. It has, however, been 

necessary in several cases to carefully study the records in- order to determine 

whether or not the snowfall, as measured, was melted and included in the given 

total precipitation for the day, and for the month. The records, as they were found 

at the Weather Bureau, did not always seem to have made this inclusion, but where 

the necessarjf data were available, they were always corrected by the writer, so that 

the totals include rain and melted snow. In several cases it was not possible to 

make these corrections, because of the insufficiency or inaccuracy of the data, but 

these cases have not been used in compiling the present totals. It should, 

furthermore, be stated that the totals on rainfall are based only upon records for 

whole months, any incomplete months having been omitted in making up the means 

there given. In "compiling the table of maximum daily rainfall (pp. 166-167), 

however, the incomplete monthly records have been used when the record for an 

incomplete mouth included a maximum figure.

In conclusion, it may be stated that the means given are based upon a series 

of observations of such varying lengths from station to station that they should be 

used only with the greatest caution. On\y means based upon a series of observation 

extending over the same years, or means reduced to the same series of years, should
CLIMATE DESCRIPTION OF TABLES. 187

be used in making any accurate comparative study of climate or for making any 

accurate estimates, plans, etc., for water resources.

The variation in rainfall, both daily, monthly, and annual, is so great at any 

station that only after a long series of observations have been obtained are we 

justified in drawing any definite conclusions concerning the rainfall to be expected. 

Unfortunately, the records for most stations in Alaska extend over short periods of 

years, and in man}7 cases do not include even one complete year. This incompleteness of most of the records is expressed by the last column of the table on page 167, 

where the years and months of the record are given. In the column headed 

"years," the number of whole }7 ear.s is given; in the column headed "months,'1 the 

number of scattered months over which the record stretches are given. In many 

cases, the number of months of record often exceeds the number of months in a 

year, but this simpty indicates that the records are based upon observations made in 

many scattering months. The record at Eagle furnishes a good illustration of this, 

where we find that the record covers fifty-two months but no years.

The rainfall data from Weather Bureau and voluntary stations are based upon 

observations made daily by means of the standard Weather Bureau cylindrical gage, 

and with one or two exceptions are believed to include melted snowfall as well as rain.

The rainfall records kept by the commercial companies have not been incorporated in the accompanying tables, because no information has been received 

concerning the t}*pe of gage used by them.

RECORDS OF FROST AND ICE.

Records of the dates of occurrence of first and last frosts in fall and spring 

and the dates of first and last killing frosts were made very sporadically until the 

establishment of the experiment stations. The records show many gaps and omissions. The table presenting the results of these observations shows their character 

better than verbal description.

Dates of opening and closing of streams and harbors have also been kept 

intermittently by various volunteer observers, and their results have been incorporated in a separate table. Since observations on frosta and stream ice require no 

apparatus, the}7 are perhaps, so far as they are given, worthy of more confidence 

than some of the instrumental observations, for many voluntary observers were 

without special preliminary training.

DESCRIPTION OF THE SYNOPTIC TABI/ES.

The results of the climatologic observations are presented in general tables, 

and figures for the monthly rainfall at the individual stations are added.

Locations of stations. The following table presents an alphabetical list of the 

stations from which records have been obtained. For each station is given the 

latitude and longitude, the elevation above mean sea level, when known, the limiting 

dates of the period over which the observations extended, the number of whole 

years and months during which observations were carried on, and organizations by 

which the records were made (see also PI. XVIII).

The latitudes and longitudes were first taken from the official records of the 

United States Weather Bureau and from Ball's Pacific Coast Pilot. They were 

then compared with the large scale maps of the Coast and Geodetic Survey and the
138 GEOGRAPHY AND GEOLOGY OF ALASKA.

United States Geological Survey, and in some instances with maps of special 

districts of Alaska published by the United States Geological Survey.

Alaskan nieteorolwjic stations, ujith locution and length of record at each.

Reference number.

43 

20 

22 

23 

26 

38 

85 

25 

37 

17 

47 

36 

24 

10 

34 

1 

2 

29 

44 

45 

4 

5 

11

31

3 

21 

13 

14

46 

16 

18 

8 

42 

28 

9 

32 

39 

27 

30 

7

6 

40

41

12 

15 

19 

38

Station.

Bering Island .... . 

Bethel Mission .... 

Camp Oolomiji- .... 

(Tamp Davidson . . . 

Oarmel Mission....

Copper Center .....

Eagle ( Fort Egbert) 

Fort Alexander. . . .

Fort Reliance .... .

Fort Wrangell .....

(2) (wharf)....

Kikiktak (Friends' 

Mission).

Kodiak (1) ........

(2) (Woody 

Island).

Onialik (mine) ....

St. Michael ........ 

St. Paul Island .... 

Sitka ..............

Tanaua (1) (Fort 

Adams) .

(2) (Fort Gibbon).

Utkiavi (Point 

Barrow).

Latitude 

(north)

62 37 

52 15 

52 58 

52 12 

60 58 

67 25 

64 41 

68 57 

66 50 

55 20 

61 68 

64 45 

58 57 

01 06 

64 10 

5-1 46 

56 28 

63 50 

62 16 

61 66 

58 19 

58 19 

60 32

67 00

57 22 

52 00

57 48 

57 48?

61 30 

55 45 

55 OS 

60 28 

64 41 

65 02 

60 85 

68 25 

65 30 

68 28 

57 15 

57 OS

59 28 

65 10

65 12

61 03 

57 85 

53 52 

71 17

Longitude 

(from Greeun-ich).

160 08 W. 

174 15 

172 26 

1C.5 55 B. 

161 62 W. 

HO 59 

140 54 

158 21 

1-14 04 

100 38 

143 20 

141 10 

158 21 

146 20 

139 30 

ISO SO 

132 20 

171 25 

169 50 

160 43 

134 28 

134 28 

151 19

162 00 .

131 29 

177 25 E. 

162 25 W. 

152 25?

156 59 

100 40 

16S 10 

146 40 

157 58 

162 40 

145 40 

. 166 88 

150 15 

162 10 

170 10 

185 19

136 20

152 45

152 00

151 10 

157 50 

166 31 

156 40

Elevation.

Feet. 

R. JO 

13 

8 

20

650

30 

1,005 

573

K. SO 

20 to SO 

30 to 36 

80? 

500?

80?

20 ± 

20 

50?

40,80 

10.1 

50? 

60? 

15? 

700

26 to 28

80to(?) 

40 

13 to 63

200

25? 

10,13,15

17

Length of record.

Limitin 

From 

Sept. ,1882 

May, 1879 

July, 1880 

May, 1882 

Nov., 1885 

Oct., 1889 

May, 1890

Nov., 1898 

Sept., 1889 

July, 1902 

Oct., 1882

Aug., 1881

Sept. ,1882 

June, 1868 

May, 1868 

Oct., 1894 

Oct., 1893 

Aug., 1883 

June, 1881 

Dec., 1898 

June, 1870

Sept., 1897

May, 1881 

May, 1886 

Oct., 1868

July, 1882

Aug., 1902 

Nov., 1881 

May, 1883 

Oct., 1882 

Jan., 1854 

Sept. ,1899 

Aug., 1894 

Sept. ,1900 

July. 1877 

Oct., 1869 

Nov., 1867

Nov., 1898

Aug., 1882

Aug., 1901

Nov., 1898 

Aug., 1883 

Sept., 1878 

Oct., 1881

K dates.

" -- /

To £

Mar., 1891 

Aug., 1886 

May, 1881 

May, 1886 

Feb., 1886 

July, 1890 

June, 1891 

July, 1902 

 Aug., 1900 

Oct., 1902 

Dec., 1902 

Bee., 1902 

June, 1886 

Dec., 1902 

May, 1886 

Sept., 1870 

Aug., 1882 

Sept., 1902 

Aug., 1901 

May, 1886 

Feb., 1897 

Bee., 1902 

Dec., 1902

Dec., 1902

Bee., 1902 

Apr., 1886 

Nov., 1899 

Dec., 1902

May, 1886 

Sept.. 1902 

May, 1883 

Aug., 1884 

Apr., 1896 

Apr., 1885 

Dec., 1902 

July, 1896 

Jan., 1902 

July, 1901 

May. 1883 

Dec., 1902

Dec., 1902 

May, 1886

Dec., 1902

Dec., 1902 

Jan., 1886 

May, 1886 

Aug., 1902

0

3 

0 

S 

0 

0 

0 

0

1

10 

0

0 

2

0

1

2 

2

6 

0

2 

4 

5

3

16 

0 

1 

0

0

0 

0 

0

0 

0

1

1

0 

7 

1 

17

0 

0

0

4 

2 

4 

1

6 M ^q

44 

10 

11 

13 

4 

10 

14 

6 

20 

28

6

28 

23 

00 

18 

16 

40 

83 

21 

23 

89 

1 

81

15

43 

12 

35 

34

41 

2 

18 

16 

16 

12 

20 

12 

7 

28 

35 

44

31

27

IS

2 

4 

28 

23

Observations byS.S.; W. B. V ... 

S.S.. ...........

s.s .............

8.S. ............

W.B.V.? ....... 

C.nndG.8--.... 

C. andG.S. .... 

W.B.V.........

P. S.. ........... 

W.B.V. ........

W.B.V......... 

W. B.; W.B.V..

S.S .............

W.B.V.........

8.8 ...........

P. S .............

P.S.; S.S .......

W.B.V.........

W.B.V.........

S.S. V ..........

8.8.V.; W.B.V. 

W.B.V.........

P. 9.; S. 8.; W. 

B.V.

W.B.V.........

S.S.; W.B.V ... 

8.8 ............

P.S.; W.B.V... 

W.B.V.........

s.s.v ..........

8.S. ............

s.s.............

S.S.: W. B. V ...

S

O

W.B.V.........

W.B.V.........

W.B.V.........

S.S.; W. B. V ... 

8.8 ............

P. S.: S. 8.; W. 

B., W.B.V.

W.B.V.........

8.8.............

W.B.V..... ... 

W.B.V. ........

S.S.V .........

s.s.............

8. 8.; W.B.V...

Authority for 

latitude and 

longitude.

tr.S.G.S.,1898. 

C. andG.S., 1896. 

C. andG.S. ,1896.

U.S.G.P.,1898. 

U. S.G.S.,1904.

i:.s. G.S.

U. S.G.S.,1903. 

l:.S,G.S.,1899.

r. s. G. s.

U.S. G.S. ,1900. 

C. and G.S. 

P. C. P. 

C. and G.H., 1863 

C. and 0. S.

U.S. G.S. ,1898. 

P. C. P.

C. and G.S. 

(.'. and G. S.

U. S.G. S.,1898.

U. S.G.S.,1900. 

U. S.G.S.,1903. 

U. S. G. S. 

G. and G.S. . 

C. and G.S. 

U.S.U.b.,1902.

U.S. G.S. ,1899. 

U.S.G.S.,1902.

NOTE. In " Elevation " column '' R" means above river level, instead of sea level.
CLIMATE, DESCRIPTION OF TABLES. 139

Each station in this alphabetical list is preceded by a reference number which is 

used in the succeeding1 tables. As the stations arc grouped in succeeding tables by 

climatologic provinces, the names are not in alphabetic order.

Table of extreme temperatures. The table on page 159 shows the absolute maximum and absolute minimum temperatures which have been observed at each of the 

stations during the period of years indicated in the last two columns of the table and 

the appropriate remarks. In the column headed "Extremes," are given the highest 

and lowest temperatures observed at each station within the period indicated, and 

also the difference, expressed in degrees Fahrenheit, between the highest and the 

lowest temperatures. The "Extremes" column, therefore, shows the extreme 

temperatures that have been experienced at each station, but not the extremes that 

might be expected within any one }rear. The table is of particular interest, as it 

shows the extreme temperatures observed in each month at each station and gives 

some idea of the amount and distribution of the extreme ranges of temperature over 

Alaska. These temperatures, however, have rarely been attained twice at the 

respective stations. They show what must be provided against in extreme cases, 

rather than what may be expected in an average year.

Table of precipitation. The table on page 162 shows the average monthly and 

annual precipitation, including melted snow, and also the average number of days 

having a precipitation of 0.01 of an inch or more. This table may be expected to 

give, as far as the lengths of the individual records permit, a fair idea of the 

geographic and seasonal distribution of rain and melted snow over Alaska. It also 

affords material for the estimation of the average intensity of the monthly and 

annual rainfalls, since the mean monthly rainfall divided by the mean number of 

days with rain in the month gives the average amount of rain for each rainy day. 

The same may also be said for the column headed "Year." Typical rainfalls are 

also shown graphically on PI. XIX.

Table of heavy rainfalls. The table on page 166 is supplementary to the lastmentioned table, and shows the absolute maximum recorded rainfall in twentyfour hours during each month of the period over which the observations extend. 

The chief interest of this table lies in the fact that it enables the heaviest rainfalls of short duration in Alaska to be located and compared. It should be of 

considerable interest to those interested in agriculture and water powers, since 

the character of the rainfall is very important in investigations in both those lines.

Table of rainy days. The table on page 168 gives the maximum and minimum 

number of rainy days observed, for each month and year, and repeats the average 

number of rainy days for each month in the year, already given.

This table is particularly interesting, as it shows the extreme fluctuations in 

the raininess of any district; but its value varies according to the number of 

observations which have been made.

Table of dates of frost*. In the table on page 171 are shown the dates of the 

earliest killing frost in the fall and the last killing frost in the spring for all those 

stations at which these data were attainable. This table is, therefore, of prime 

interest to those who are interested in mining or in agricultural pursuits, since 

it serves to give an approximate idea of the length of the working and the growing seasons.
140 . GEOGRAPHY AND GEOLOGY OF ALASKA.

Tables of stream and harbor ice. On pages 174 to 176 observations on the occurrence of ice in streams and harbors have been brought together in tabular form, 

and will prove of most .use to those who are interested in navigation. The 

tables also show the approximate times at which high water and low water may 

be expected,

CLIMATIC PROVINCES OF ALASKA.

The climate of Alaska is by no means so uniformly arctic as is usually 

believed, but is such as would naturally result from its geographic position, 

its extent, and its varied topographic features.

The mere fact that Alaska stretches through 20 degrees of latitude and 54 

degrees of longitude would alone be sufficient to bring about marked climatic 

differences. The northernmost point is within 18 degrees of the pole, while the 

southernmost lies in about the latitude of Liverpool, England. Its easternmost 

part, lying under the shelter of the coast ranges of British Columbia and bathed 

by the warm waters of the Pacific, is 2,500 miles distant from the westernmost 

of the Aleutian Islands, in the vicinity of the Siberian coast and the cold Arctic 

current. '

Three seas, each with its own conditions of. temperature and ice-covering, 

border Alaska and contribute to the multiplicity of climatic provinces. On the 

south it is washed by the warm Pacific; on the west it fronts upon the Bering Sea, 

which is essentially a body of "cold water, whose northern half is covered with ice 

during six months of the year; while its northern coast is for nine months of the 

year locked in the ice of the Arctic Ocean.

The two mountain ranges that traverse Alaska from east to west divide the 

country into districts which differ very sharply from one another, both in temperature and in precipitation.

Last, but not least, may be mentioned the fact that Alaska lies in the northwest 

corner of at great land area, the North American continent, and forms a portion of 

the north and east coast of a still greater water body. This fact alone is sufficient 

to render Alaskan climate of decided interest to all students of climatology, as well 

as to give it peculiar features.

Previous studies of the climate of Alaska, as well as the experience of travelers, 

showed that the region may be divided into climatologic provinces very closely 

coincident with the physical province:* already discussed in foregoing chapters. The 

latest observations do not materially modify these divisions, but permit a somewhat 

more detailed subdivision to be made of one or two of the provinces. Alaska is here 

divided into eight climatic provinces, whose names and boundaries are as follows:

Pacific coast climatic province. The Pacific coast province reaches from Dixon 

Entrance to Kodiak Island and includes all the islands of southeastern Alaska and 

the region lying between the ocean and the first range of mountains along the coast 

from Cross Sound to the beginning of the Alaska Peninsula. This is essentially a 

temperate and humid region. (See Nos. 1-14, tables, pp. 158 et seq.)

Alaska Peninsula climatic province. The Alaska Peninsula climatic province 

includes the stations of Ugashik, Mine Harbor (Herendeen Bay), Cold Harbor (Unga 

Island), and Morzhovoi. (See Nos. 15-18, tables, pp. ,158 et seq.) The climate here
CLIMATIC PROVINCES. 141

differs but in degree from the first province. It is in general somewhat more humid 

and milder than in the Cook Inlet district, approaching more nearly that of the 

Sitka district. The temperature ranges are more nearly of the insular type.

Aleutian Islands climatic province. The Aleutian Islands province includes 

the Aleutian Islands, to which, for the sake of comparison, Bering Island, of the 

Commander group, has been added. (See Nos. 19-23, tables, pp. 158 et seq.). The 

climate of this province is characterized by moderate temperatures, limited ranges 

in temperature, and moderate humidity.

Bering Sea coast climatic province. The Bering coast province begins at Fort 

Alexander in the northeast corner of Bering Sea and includes all the Bering Sea 

coast to Cape Prince of Wales. (See Nos. 24-28, tables, pp. 158 et seq.). Its 

climate is characterized by greater temperature ranges than are experienced in the 

foregoing provinces, while the precipitation is considerably less.

Bering Sea Islands climatic province. This province is evidently related to the 

Bering coast province, but differs slightly from it in ranges of temperature. It 

includes the islands of St. Lawrence (Gambell), St. Paul, St. George, and St. 

Matthew. (See Nos. 29 and 30, tables, pp. 158 et seq.).

Arctic coast climatic province. The Arctic coast province includes the Arctic 

coast stations from Cape Prince of Wales northward to Point Barrow and beyond, 

and southward to the Rocky Mountains. It is characterized by a long period of 

cold weather, which prolongs the winter through two-thirds of the year, and by 

a precipitation of about the same amount as that prevailing over the arid areas of 

Nevada and Utah. (See Nos. 31-33, tables, pp. 158 et seq.).

Interior climatic province. The Interior province includes the central plateau 

region between the Rocky Mountain system on the north and the Pacific Mountain 

system on the south. It is characterized by great extremes of temperature and 

a very moderate rainfall, such as prevail in eastern Oregon and Washington. 

Thirteen stations included in this province are listed as Nos. 34-46 in the climatic 

tables (pp. 158 et seq.). Of these stations, Fort Reliance, Camp Davidson, Eagle 

(Fort Egbert), Circle, and Camp Colonna are located in the eastern section; Rampart, 

Fort Adams (Tanana 1), and Fort Gibbon (Tanana 2) are in the central section; and 

Nulato (St. Peter Mission), Anvik, Holy Cross (mission), Ikogmut, and Kolmakof 

are in the western section.

Copper River Plateau climatic province. The station of Copper Center, which 

is given as the last, is here classed under a provisional province, the Copper River 

Plateau, since it shows some features characteristic of the interior climate and 

some suggesting the Pacific coast climate. (See No. 47, tables, pp. 158 et seq.).

17211 No. 45 06 10
142 GEOGRAPHY AND GEOLOGY OF ALASKA.

Table of mean temperatures for certain

Station.

Coast.

Sitka.. ......................................

Do ......................................

Do ......................................

St. Michael. . ................................

Interior.

Foreign.

Latitude.

O f

54 46

57 3

58 19

61 3

57 48

53 53

58 43

63 28 

65 20

62 16

64 45

45 30

60

48 10

60

Longitude.

O '

130 30

132 28

151 10

152 19

166 24

161 48

166 16

159 50

141 10

76

97

123 30

25 E.

Elevation.

Feet. 

20-30

25-35

13

13

30

500?

573

Jan.

°F. 

37.8

26.2

31.4

34.2

27.5

23.8

5.41

30.0

33.5

7.4

- 7

17.5

-6.4

-24.8

11.9

-11.0

37.1

24.1

20.9

Feb.

36.9

30.8

33.0

24.7

15.5

15.3

28.2

31.9

30.5

- 2.3

7

5.8

- 5.0

36.7

38.4

Mar.

°F. 

42.4

31.6

37.2

33.5

30.8

23.6

30.4

32.6

8.9

15.6

41.7

26.2

Apr.

°F. 

46.3

42.7

41.9

40.1

31.6

37.7

35.6

35.2

19.9

1.2

26.0

17.4

29.3

41.5

45.6

44.1

May.

°F. 

53.0

49.3

47.0

46.9

47.7

43.1

43.2

40.9

40.4

33.1 

32

40.9

33.2

42.2

63.6

53.6

50.9

44.1

June.

°F.

57.8

55.3

52.4

53.6

49.6

63.1

45.9

46.3

42

32.8

58.6

52.6

61.5

54.0

54.8

56 9

a Compiled by A. H. Brooks from the following publications: Dall, Wm. H., Coast and Islands of Alaska: Meteorology, 

Appendix 1, Coast and Geodetic Survey, 1879. Reports of United States Weather Bureau. Georgeson, C. C., Agriculture in 

Alaska: Dept. of Agriculture, Office of Experiment Stations, Bulls. 48, 62, 82, 94, ana Ann. Kept, for 1901. Jackson, Sheldon, 

Reports on Introduction ol Domesticated Reindeer in Alaska, U. S. Bureau of Education. Collier, Arthur J., Reconnais-
MEAN TEMPERATURES. 143

Alaskan and other stations."

Station.

Coast.

Fort Wrangell ...............

Do .......................

Valdez.. .....................

Do .......................

St. Michael ..................

Utkiayi (Point Barrow) ..... 

Interior. 

Holy Cross (mission) ........

Foreign.

Winnipeg, Canada ...........

July.

°F. 

60.0 

58.2 

55.4 

54.4 

56.6 

50. ft

58.7 

54.7 

50. 6 

49.6 

53.6 

51

38.1

57.9 

64.2

70.4 

84.0 

56.6 

57.1 

62.6

Helsingfors, Finland ........ 61. 9

Aug.

56.8 

57.5 

55.9 

56.6 

55. 0

56.4 

55.2 

51.9 

50.3 

51.9 

49

37.9

51. 8 

53. 6 

49.1

68.7 

61.5 

66.8 

56.6 

60.6 

58.3

Sept.

0^,'

52.4 

52.3 

51.5 

52.3 

49.9

49 

50.0 

45.5 

46.0 

43.9 

41

27.8

42.5 

42.6 

40.4

57.7 

49.0 

52.7 

52.8 

62.7 

50.5

Oct.

°F. 

49.0 

45.9 

44.9 

45.7 

41.9

35.4 

42.3 

37.6 

40.4 

30.5 

36

4.4

29.6 

16.9 

20.1

43.1 

36.5 

47.7 

46.4 

41.9 

43.9

NOT.

°F. 

41.6 

33.5 

38.1 

39.8 

31.2 

22.4 

29.2 

34.7 

33.6 

34.6 

15.6 

8

- 6.0

12.5 

-10.8 

-10.0

34.5 

18.0 

42.4 

40.6 

32.1 

33.7

Dec.

OJt.'

39.3 

32.8 

33.3 

36.0 

29.3 

21.6 

17 

30.5 

30.1 

32.8 

4.8 

0

-15.4

1.8 

-26.0 

 7.4

17.8 

3.0 

38.2 

37.8 

25.6 

21.7

Annual.

47.8 

43.0 

43.3 

44.5 

40.9

40.6 

38.7 

39.3 

26.1 

22

7.7

21.2

42. 1 

29.6 

46.1 

46.1 

41 9

Length of record.

Limiting dates.

From 

1869 

May, 1868 

Jan., 1828 

Apr., 1881 

May, 1883 

1899

Jan., 1869 

Oct., 1827 

June, 1872 

July, 1874 

July, 1850 

JNoy.,1894 

(Sept., 1852

1899

To 

Aug., 1882 

Dec., 1876 

Sept., 1887 

Dec., 1896

Aug., 1896 

Apr., 1868 

May, 1886 

June, 1886 

June, 1852 

July, 1896 

Aug., 1883

1900

Yrs.

4 

45 

5 

2

1

8 

6 

2

11

I '

2

1

1

39.2 ............ ............. 1

Mos.

18 

2 

18 

28 

10

54 

20 

32 

12

10

10

sance of the Cape Nome and Adjacent Gold Fields of the Seward Peninsula (by Brooks), U. S. Geol. Survey, 1901. Collier, 

Arthur J. , Reconnaissance of the northwest part of the Seward Peninsula: Prof. Paper U. S. Geol. Survey No. 2. Schrader,

P. C., Reconnaissance of a Part of Prince William Sound and the Copper River district: Twentieth Ann. Rept. U. S. Geol. 

Survey, part 7, pp. 369.
144 GEOGRAPHY AND GEOLOGY OF ALASKA.

GENKRATj CLIMATOLOGY OF ALASKA.«

The Alexander Archipelago and adjacent parts of the mainland forming southeastern Alaska have the most temperate and humid climate of the Territory, The 

moisture-ladened winds of the Pacific precipitate their waters in this belt, producing 

an annual rainfall averaging between 80 and 130 inches. Three-fourths of the 

precipitation occurs in the winter months, from November to March, inclusive, and 

is characterized by long, incessant rains and drizzle. Sitka, located on the outer 

shore of the archipelago and exposed to the full influence of the Pacific, has an 

annual rainfall of 88 inches. In general, this province has cool summers and comparatively warm winters; but it is essentially a region of cloudy and rainy weather, 

having on an average not more than one hundred clear days in the year, and these 

largely in the spring months. April to July includes the driest months, while the 

greatest precipitation is in the autumn. Fogg3' weather is also a characteristic of 

this coast and adds to the dangers of navigation. The snowfall is insignificant, many 

years showing none.

The temperature throtighout southeastern Alaska is remarkably equable. 

The extremes recorded at Sitka show for August, the hottest month, an extreme 

range of from 35° to 87° F., and for the coldest month, February, a range of from 

3° to 54° F. The mean temperature for January is 33°, and for August 56°, a range 

of only 23°.

Juneau, on the mainland, is less subject to the oceanic influence. In recent 

years the precipitation here has not been so great as at Sitka, and tlie mean annual 

temperature is several degrees lower, the difference being more marked in winter 

than in summer. The snowfall at Juneau at tide water is very small, but is heavy 

in the mountains near at hand.

In the southernmost part of this coastal zone the climate is warmer and even 

more humid than at Sitka. Records kept at Fort Tongass, located on Dixon Entrance 

and subject to1 the full influence of the ocean, show an average of 133 inches of rainfall and a mean annual temperature of about 48°. These records, however, embrace 

observations covering a period of only two years.

Sitka has a mean annual temperature only 2° colder than that of Port Angeles 

on Puget Sound, or of Scotland in the British Islands. Its rainfall, however, is 

about three times that of Puget Sound and twice that of Scotland (see pp. 162-165). 

Its average temperature is 2° warmer than the annual mean of Ottawa, Canada, and 

the climate does not show anything like the extremes of winter and summer, though 

its rainfall is nearly three times as great. It has a far more equable climate and a 

lower mean annual temperature than the populous cities of Winnipeg, Canada; 

Christiania, Norway; and Helsingfors, Finland.

The enormous precipitation along the coast has a great effect on vegetation. 

The seaboard of southeastern Alaska is densely timbered with forests chiefly made 

up of spruce and hemlock, with some red and yellow cedar and other species. 

Shrubbery and all other plant life grows rank. The dense foliage of the trees and 

shrubbery shields the ground from the sun's rays on the comparatively few clear

a Written in cooperation by A. H. Brooks and C. Abbe, jr.
GENERAL CLIMATOLOGY. 145

days, and the moisture of the heavy rainfall is long preserved in the moss-covered, 

sponge-like soil. This dense growth of trees and shrubs is in strong contrast to the 

open forests of the interior and the treeless region of the barren grounds to the 

north.

There are few climatic records for the seaboard between Cross Sound and Cook 

Inlet. The outer coast line has probably a somewhat colder mean annual temperature than Sitka, with somewhat less rainfall. According to the reports from the 

Copper River, the spring and early summer months arc usually bright and clear, 

and midsummer is sometimes quite hot. The fall months are rainy as a rule, while 

the winter is probably much more severe than in the southeast. July and August 

are probably rather free from frosts along the coast. In the Copper River Plateau 

region frosts are liable to occur at a,ny time in the year, but are rare in June, 

July, and early August. The annual snowfall, which begins in October and November, averages from 2 to 4 feet, somewhat more than in the Yukon basin.

The inland fiords are decided^ colder than the outer coast line. Some incomplete observations at Valdez show that the winter months are on the average 10° 

and the summer months about 5° coldor than the corresponding periods at Sitka, and 

the annual precipitation is probably 50 per cent less. Snow, said to amount to 7 or 

8 feet annually, is reported to fall from November to May, when it gives place to 

the rain and fog which extend through early June. June and July are the clearest 

months in the year, while the fall is again rainy and foggy.

At Kodiak Island, which is in about the same latitude as Sitka and is fully 

exposed to the equalizing influences of the Pacific, the mean annual temperature is 

4° lower than at Sitka and there is 20 per cent less rainfall. The Cook Inlet region, 

including the lower part of the Sushitna basin, though somewhat colder than that 

part of the seaboard which lies directly on the open ocean, has probably the most 

delightful climate of any portion of Alaska. While the winters are cold compared 

with southeastern Alaska, the upper part of the inlet being usually locked in ice from 

November to May, they are not so severe as those of Bering Sea. The charm of the 

Cook Inlet climate is its bright, clear weather in the spring and summer, when 

there is just enough rainfall to insure ample water for the growth of vegetation.

The shores of Cook Inlet and the lower slopes of the adjacent mountains are 

timbered with spruce, birch, cottonwood, willow, and alder, which latter grows in 

dense thickets along the water courses. The eastern side of Kodiak Island is 

sparsely forested, but the Alaska Peninsula and the Aleutian Islands are treeless, 

except for some stunted willows.

The Aleutian Islands, bathed on one side by the warm waters of the Pacific 

and on the other by the colder waters of Bering Sea, and far from the continental 

land mass, have a climate distinctly oceanic in character. The records show it to 

be colder than that of southeastern Alaska, with 5 to 10 per cent less rainfall. 

Precipitation at Unalaska, in the eastern part of the archipelago, is greater during 

the fall and winter months. The reported preponderance of clear days in January 

and February is not borne out by recent records in this region. The table on 

page 168 shows twenty-four rainy days in these months, against thirteen in May 

and June. Northerty and northwesterly winds prevail in the winter and southerly
146 GEOGBAPHY AND GEOLOGY OF ALASKA.

and southwesterly during the summer. The mean temperature for the winter 

months is but little colder than for the corresponding periods at Sitka. but the 

annual mean is lowered b}T the cooler summers. The extreme range is 73° at 

Unalaska, 90° at Sitka, and 102° at Skagway. The fogs which are ever hanging 

about these islands make the passage of the straits perilous to navigation. 

Though timber is absent, grass grows luxuriantly.

Bering Sea is a cold body of water, with a mean annual temperature of 

about 39° F. It is practically closed against the warm influence of the Pacific by 

the barrier of the Aleutian Islands, and its cold temperature, incident to the high 

latitude, is probably increased by some influx of cold waters of the Arctic Ocean 

through Bering Strait. Fogs are very prevalent throughout the open season and 

seriously hamper navigation. The winter ice extends from Bering Sea as far 

south as the mouth of the Kuskokwim. and usually blocks navigation from about 

November until the end of May (see pp. 174-176).

The climate of the eastern shore of Bering Sea is rigorous in winter, growing 

more so toward the north, but its summer temperature is only a few degrees 

cooler than at Sitka. St. Michael, near the mouth of the Yukon, has a mean 

annual temperature of about 26°, but a summer extreme of 77° and a winter 

extreme of 55° are on record, giving an extreme range of 132C . Sitka has 

but 90° range. The annual precipitation at St. Michael is only about 18 inches, 

and much of that falls in the form of rain from Ma}^ to October.

In the Seward Peninsula, which forms the north shore of Bering Sea, June, 

Jul}", and August can be counted the summer months. The snow has usually 

disappeared by the 1st of June and does not begin to fall again until September. 

In some years June and July are delightfully dry and pleasant months, but the 

colder rains, which are apt to begin in August and practically continue until snow 

flies, often accompanied by severe winds, are excessively trying. During 1901 

the average temperature was 44° in July and August and 40° in September," the 

number of rainy days during these months aggregating thirty-six. At Port 

Clarence two years' records* showed a mean annual temperature of 22°, with a 

minimum of 38° and a maximum of 77°. The precipitation of the, only year in 

which a record was kept amounted to 5.58 inches. The ground is usually found 

to be frozen a foot or two below the surface throughout the year.

The climate of the Seward Peninsula during the late summer and early fall 

is probably the worst of any part of Alaska which is inhabited by white men, 

for at this season of the year it is essentially arctic in its character and similar 

to that of the Arctic province. The utter lack of timber makes it impossible for 

the traveler to find shelter and often hardl}7 fuel. While the winter temperatures 

of the northern Bering Sea coast lines are usually not so low as those of the interior, 

the greater humidity of the atmosphere makes them harder to resist.

The Arctic province, which includes the seaboard of the polar sea, is similar 

in character to the northern part of Bering Sea, but colder. At Point Barrow, 

the northernmost cape of Alaska, the mean annual temperature is less than 8°, 

with a precipitation less than 8 inches. The extreme of summer heat recorded

aProf. Paper U. S. Geol. Survey No. 2, p. 7.

6 Reconnaissance of the Cape Nome and Adjacent Gold Fields of the Seward Peninsula, 1900, p. 163.
GENERAL CLIMATOLOGY. . 147

at this point is 65°, in July, and of cold 55°, in February, giving an extreme 

range of 120°. The summer extends from about the middle of June to the 

middle of August, when snow begins to fly. Shore ice begins to form along the 

north Arctic coast early in September and remains until July. The Arctic pack 

ice has been known to come in on shore as early as August 14, but on that 

occasion went off again on the 28th of the same month (1902). Inland the summer months are usually clear, but the sea is often mantled in fog. The arctic 

littoral of Alaska is part of the broad tundra or barren ground belt which encircles 

the polar sea. The surface is everywhere covered with a dense growth of moss 

and grass and abundant wild flowers, beneath which the ground is perpetually 

frozen. Along the watercourses willows are found in thick growths, clinging close 

to the ground to avoid the icy blasts of the arctic winds. Away from the watercourses there is no timber of economic value, though some stunted shrubbery is 

found. It is remarkable that the observed total precipitation in the Arctic province averages about one-half that of the dry interior, and is comparable with the 

conditions prevalent iu northern Nevada.

The climate of the Alaskan interior is continental in its character, semiarid, 

with great extremes of heat and cold. On ascending the Yukon, one gradually 

passes out of a relatively humid coastal belt, and at the international boundary 

reaches a point where the annual rainfall, as far as recorded, is less than 10 

inches. Here the average temperature for December to February is from 5° to 

10°, with an extreme minimum of 70° to 80°, while in the summer months 

of June, July, and August, 50° to 60° is the mean; the maximum, 90°. Frosts 

majr occur at any time during the year, though there is usually a period of about 

30 days, from the middle of June to the middle of July, which is without frost. 

The heaviest precipitation is in July, August, and September, and is always 

moderate in amount, while the winter snowfall aggregates from 2 to 3 feet. 

At other points in the Yukon basin less reliable records place the snowfall at 

from 4 to 6 feet. The Yukon usually begins to break in May, by which time 

the winter accumulation of snow has disappeared from the lowlands. It freezes 

again in early November, but after the middle of September the ice begins to 

run and navigation is interrupted. In spite of the rigorous cold of winter, the 

climate is less trying to man than some less severe though humid regions. Even 

during the extremes of cold, traveling with dog teams is not impossible, unless 

the wind is blowing. ( The lowlands of the interior are usually well forested with 

spruce, cottonwood, birch, willow, and alder. Away from the rivers and streams 

the forest becomes more open, and ceases altogether 2,000 or 3,000 feet above 

sea level. The region nearly everywhere is covered with a coating of thick moss, 

except in the open lowland tracts, where grass takes its place, and a few inches 

below the surface soil the ground in many places remains frozen throughout the year.

In this connection it is interesting to note that there is only one instance on 

record where excavation in this northwestern region has gone below the zone of 

perpetual frost. Tyrrell ° describes a shaft in the Klondike placer field which 

pierced the frozen ground to a depth of about 200 feet. In the Nome region a

a Tyrrell, J. B., A peculiar artesian well in the Klondike: Eng. Min. Jour., vol. 76, 1903, p. 188.
148 GEOGRAPHY AND GEOLOGY OF ALASKA.

shaft 120 feet deep did not reach below the level of perpetual frost. It must 

not be supposed that there is a continuous incrustal of frozen soil, for the placermining, excavations in man}' places fail to reveal any.

CUMATTC FEATURES, BY PROVINCES.

PACIFIC COAST CLIMATIC PROVINCE.

Rain/all. The Pacific coast province, and more particularly the "panhandle," 

is well known for its heavy rainfall and cloudy weather. The tables on pages 

162 et seq. and PI. XIX show that this portion of Alaska, as well as the northwest 

coast of the States, has a rainfall comparable only to that of the Aleutian Islands, 

the immediately adjacent coastal portions of British America, and the coast of Washing-ton and Oregon. In general, however, the precipitation within Alaska falls 

somewhat short of that recorded in the latter district. The heaviest annual rainfalls in this province occur at Nuchek (190.09 inches), Fort Tongass (133.10 

inches), Orca (129.30 inches), Juneau (84 to 93 inches), Sitka (88.1 inches), and 

Fort Liscum (81.3 inches). Fort Wrangell, Killisnoo, and Kodiak stand next, with 

50 inches or more, while Tyonok, Skagway, and Kenai have only between 15 

and 25 inches.

Nearly all this precipitation falls as rain, and for the most part from September 

to January, both inclusive (PL XIX), During the other months a considerably 

smaller proportion of the annual rainfall is precipitated. The season of least 

rainfall, and consequently the one having the fewest number of rainy days, is 

generally from April to July. The table of annual and monthly rainfall (p. 162) 

shows Nuchek to be the only exception to this rule. At that station the heavy 

rains last until May and begin again in August. The table of rainy days (p. 168) 

shows that during the months of heavy rains there is scarcely a day without 

precipitation, the number of rainy days in a month running up to twenty, twentytwo, twenty-seven, and, in the case of Fort Liscum, even to twenty-eight and a 

half. On the other hand, the same table shows that even in the less rainy 

months the number of days per month on which rain falls is usually not less 

than ten, except at Skagway, Kenai, Fort Liscum, and Tyonok, where it is five 

or even less.

A feature of the local rainfalls which is often of economic importance is the 

maximum rain'fall during a limited period of time e. g., in twenty-four hours. 

If the material at hand were more complete and time allowed, a table of average 

maximum rainfalls would prove very valuable. In the absence of such a table 

the observed maximum rainfall in twenty-four hours for as many stations as 

.possible have been collected in the table on page 166. From this table some 

idea of the intensity of the rainfall may be obtained. The table shows that the 

eastern portion of the Pacific coast province is subject to the most severe downpours, as a rule, the maximum amount of rain in twenty-four hours in that 

region being from 3 to 7 inches. The western stations have downpours generally 

less than 2 inches. Orca, however, has a record of over 7 inches of rain in 

twenty-four hours, which is the heaviest reported from any Alaskan station, and
U. S- GEOLOGICAL SURVEY PROFESSIONAL PAPER NO- 45 PL. XIX

Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec.

II

(A)

Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec.

bo 

~

5-

(E)

TYPICAL MONTHLY RAINFALLS.
CLIMATIC FEATURES. 149

yet is more than 3 inches less than the heaviest daily rainfalls which have been 

recorded in the United States.

Generally the excessive rainfalls occurred during the characteristically rainj^ 

months, viz, in the fall and winter. Nuchek and Kodiak, however, again show 

variations from the general rule, as they have very heavy rains during May while 

Juneau has its heaviest rains in July and August.

Temperature. The Pacific coast province, as shown by the table on pages 158-161, 

holds an intermediate position among the climatic provinces of Alaska so far as 

temperature is concerned. The extreme ranges observed in the province cover 

about 95° F., most of the stations showing a slightly smaller extreme range. Of 

course the average annual range is considerably less. An extreme maximum higher 

than 95° has not yet been recorded in the province, the highest being 92° at Skag 

way. On the other hand, every station except Nuchek and Orca has recorded a minimum temperature falling between 3° and 43° F. It is interesting to notice 

that the highest maxima and the highest minima occur in the "panhandle," while 

the lowest absolute maxima and minima occur on Kodiak Island and along Kenai 

Peninsula.

The greatest absolute ranges in temperature, 110° and 125°, occur in the Cook 

Inlet region, and are due to the fact that the minimum temperatures fall much lower 

than those in the eastern part. The most equable temperatures of the province seem 

to prevail at Nuchek and Orca, which lie between the waters of Prince William Sound 

and the Gulf of Alaska. Here the maximum has remained below 90° and the 

minimum above 0° F., resulting in an absolute extreme range of 60° for Nuchek and of 84° for Orca. ..-.... - --. .^- + -----

(Growing season. The dates of the last frosts in the spring and the first frosts in 

the autumn with the number of intervening days free from frost are given in the 

table on page 171, in as much detail as the records permit. From this table it appears 

that among the inlets and islands of the southern panhandle district the last frost 

comes during the latter half of April and the first fall frost the end of September 

or beginning of October. Thus there results a growing season in this region of about 

two hundred days. Farther north, from Sitka to Skagway, the last spring frost 

comes about the first of May and the first frost in the fall toward the middle 

of September, thus reducing the growing season to about one hundred and seventyfive daj^s. In the Cook Inlet region the season becomes still shorter, as the last frost 

delays until May or even June while the fall frosts hurry in by the first week of 

September.

River and harbor ice. The records of opening and closing of streams and harbors by the ice are very scanty among the meteorological records examined. They 

are given in the table on page 174. From the few found it would seem that the sea is 

free from ice by the middle of March at Unga Island, but that Cook Inlet does not 

usually open before the end of that month. Ice begins to form there late in the fall, 

perhaps the middle or last week in November. Within the Alexander Archipelago, 

however, the ice has been known to form as early as the end of October, and the bay 

at Fort Tongass has been closed during the first week in November.
150 GEOGRAPHY AND GEOLOGY OF ALASKA.

ALASKA PENINSULA CLIMATIC PROVINCE.

Rainfall. The province embracing the Alaska Peninsula and the islands to 

the south is characterized by less extremes of climate than the other portions of 

Alaska. The rainfall records from this province arc not very complete, but they 

serve to show that the precipitation is much less than in the Pacific coast or 

Aleutian Islands province (see also PI. XIX). Ugashik, on the west coast, has 

an annual rainfall of only 24.41 inches, while Unga Island, off the east coast, 

receives just about twice as much, 48.78 inches. The records at Morzhovoi, 

although not complete, indicate that the precipitation increases decidedly to the 

southwest toward Unalaska Island.

The seasonal distribution of rain is in general similar to that prevailing on 

the Pacific coast and among the Aleutian Islands. There is a rainier season from 

September to January and a drier one from February to August. The contrast 

between these two seasons is much less marked in this province, however, than it 

was seen to be in the Pacific coast province. This is shown by the larger number 

of rainy days in the year, and is also apparent from a brief examination of the 

table of monthly rainfalls (p. 162). This table shows that Coal Harbor has averaged 

from sixteen to seventeen rainy days in every month; Ugashik, on the west coast, 

ranges between fifteen and twenty-six rainy days, while the stations of the Pacific 

coast province have ranges running from nine or ten rainy days in the summer 

months up to twenty-six or twenty-eight days in the fall and winter.

The heaviest twenty-four-hour rainfalls of the province show interesting 

--Variations'. "Cdal~Harbor ha&r the heaviest downpours, 1.25 to 5 inches, which are 

in excess of those occurring at most of the other stations in Alaska. Morzhovoi 

comes next with falls of from 0.40 to 2.07 inches. It is a peculiarity of these 

showers, however, that they seem to occur in any month except December, while 

at Coal Harbor the heaviest rains in twenty-four hours occur during the months 

from April to July. On the west coast Ugashik records seem to indicate that this 

portion of the province is rather exempt from such heavy rains. The recorded 

maximums lie between 0.22 and 1.20 inches. The season of heaviest rains in any 

twenty-four hours is from June to November.

Temperature. As regards temperature ranges the Alaska Peninsula and the 

Pacific coast rank together between the two extremes found in Alaska. The 

extreme annual range is not so great as that of the interior nor so limited as that 

of the more isolated islands. The two stations on the east coast of the peninsula 

show an extreme annual range of 80° or 90°, practically the same as that prevailing 

about Dixon Entrance, but on the west coast the maximum range has extended 

through 124°. This contrast arises chiefly from the fact that much lower minimum 

temperatures are experienced on the west coast than on the east, and is not due 

to any important difference between the maximum temperatures of the two coasts. 

This contrast may be traced throughout the year. Each month the minimum at 

Ugashik falls lower than at Coal Harbor or Morzhovoi, while the maximum 

temperatures, reached during July and August on both coasts, almost coincide.

Growing season. The dates of first and last frosts in this province (p. 171) show 

that on Unga Island the growing season includes about one hundred and fifty days,
CLIMATIC FEATURES. 151

and lasts from the middle of May to the last week in September. The record B

from Ugashik are too scanty to permit any such estimate for that station, but 

judging from the records at Carmel Mission, on the delta of the Nushagak Kiver, 

the number of days free from frost seems to he about one hundred and six, with 

a factor of uncertainty as to the occurrence of frosts in August.

River and harbor ice. There are no records of the dates of opening and closing 

of streams and harbors.

ALEUTIAN ISLANDS CLIMATIC PROVINCE.

Rainfall. The Aleutian Islands province ranks next to the Pacific coast 

province in amount of annual and monthly rainfall, but has a greater number of 

rainy days. Although complete records exist for Unalaska and Atka only, the 

other stations have sufficiently complete records to indicate that the average rainfall 

throughout the province will scarcely exceed 80 inches in a year. The greatest 

annual rainfall is at Unalaska, which also has the greatest number of rainy days. 

Indeed, this station has the greatest number of rainy days of any in Alaska, viz, 

250.8, although heretofore Sitka has been considered as the rainiest point in the 

United States. Here, as on the Alaska Peninsula, the heaviest rainfall occurs 

during the fall and early winter, usually in October and November (see PI. XIX). 

At Unalaska the season of heaviest monthly rains is somewhat longer than this, 

lasting from September until February, and the maximum occurs in January. 

The season of least rainfall at this station falls between June and August, yet even 

during this period the monthly rainfall averages very little under 3 inches. On the 

other islands of the province the season of minimum rainfall, so far as it may be 

determined from the insufficient records, occurs during the winter and early 

spring months. In general not less than 2 or 3 inches of rain fall in any month 

except February on Kiska Island, and the distribution of the rainfall throughout 

the year is unusually uniform. The same may be said of the distribution of rainy 

days as shown by the table on pages 168-170.

In amount of maximum daily rainfalls this province again stands next to the 

Pacific coast province. The seasonal variation of this factor is, however, less in the 

province under consideration, ranging from 5.58 inches at Unalaska to 1.75 inches 

at Unalaska and Atka. The maximum rainfalls in twenty-four hours observed on 

Kiska and Attu islands fall much below these figures. These heavy rains seem to 

characterize no one season on Unalaska, but to occur with equal frequency at 

any time between October and April. On the other islands they occur during 

July to January, but show some tendency to happen in the summer months as well.

Temperature. The table on page 158 shows that the Aleutian Islands have characteristic island climate, so far as the ranges in temperature are concerned. The 

extremes are here closer together than anywhere else in Alaska. A maximum of 78° 

is the highest that has been recorded, and the lowest minimum was 5°, observed at 

Unalaska. On the other islands the lowest minimums are much higher, 15° and 11°. 

The warm season includes June, July, and August; the cold season is most severe 

during February and March.

Growing season. Atka Island probably has the longest growing season, from 

the middle of February to the end of October, although this seems impossible. The
152 GEOGRAPHY AND GEOLOGY OF ALASKA.

partial record from Attu Island indicates that during that year the frost-free season 

lasted from early in May until the end of September, a period of about one hundred 

and thirty-five days. There is no evident reason why the growing season throughout the province should not be of about the same length as that just given for Attu 

Island.

River and harbor ice. The records of frosts and of harbor ice are very 

incomplete.

BERING SEA COAST AND ISLANDS CLIMATIC PROVINCES.

Rainfall. The precipitation in the Bering Sea coast and islands provinces is 

probably less than in the provinces to the southeast. The annual rainfall is heaviest 

about Fort Alexander, where it averages 33 inches, and it decreases in amount northward to an average of 18 inches at St. Michael. The precipitation of this province 

is thus shown to be comparable to that in the portion of the United States stretching 

from North Dakota and Minnesota on the north to Texas on the south. This moderate rainfall occurs within the relatively small number of one hundred and twenty-five 

to one hundred and sixty days.

The seasonal distribution of the rainfall (see PL XIX) seems to be quite different 

from that which prevails over the southern portions of Alaska, since the greatest 

amount of rain falls from July to October. Fort Alexander shows a distinct season 

of maximum rainfall limited to July, August, and September, and a very uniform 

monthly amount of from 4 to 5 inches during those three months. Farther north, at 

St. Michael, the average monthly precipitation increases regularly from 1.27 inches 

in June to 4.02 inches in September, and then takes a sudden drop to 1.70 inches in 

October. On St. Paul Island, however, the brief records show a much greater 

maximum, which occurs during the months of September, October, and November. 

This island has as many rainy days as Sitka two hundred and seven and one-half 

the precipitation 40.68 inches from which it may be seen that the Bering Sea 

islands have a relatively drier climate than the coast. The table of rainy days (p. 168) 

brings out this difference even more strikingly, perhaps. It shows that, month for 

month during the rainy season, the islands have twice as many days with 0.01 inch 

or more of rain than does the coast. Strangely enough, however, these conditions 

are reversed during the months of June and July, as then the coast stations have 

twice as many rainy days as the islands.

In excessive rainfall in twenty-four hours this province (see p. 166) ranks next 

after the Aleutian Islands. On the coastal portion the heaviest daily rainfall occurs 

during the midsummer months, and ranges between 2 and 2.75 inches. On the 

island of St. Paul it seems to occur during the winter months, while during the 

summer this section receives the lightest of its maximum daily precipitation. As is 

apparent from the maxima just given, none of these twenty-four-hour quantities 

are very heavy, and the smallest which have occurred along the coast are very small 

indeed, even when compared with the scanty rainfalls of the interior province. The 

records containing these minima are from Omalik and are very incomplete probably 

too faulty to warrant any conclusions at all to be drawn from them.
CLIMATIC FEATURES. 153

Temperature. The extreme annual range in temperature of the Bering Sea 

coast province stands between that of the Pacific coast province and that of the 

interior. Although the maximum temperatures exceed those of the Aleutian Islands 

very little, the long winter, during which the sea is here covered with ice, suffers 

a fall in temperature which brings the minima far below those of the former 

province. The winter of the Bering Sea islands is also distinguished by these low 

temperatures. The reported extreme minima from the mainland range between

 30° at Fort Alexander to 70° at Carmel Mission, and average about 52°. 

On the islands the lowest temperatures observed have been 10° on St. Paul and

 31° on St. Lawrence. The extreme cold weather occurs during February and 

March, but the short record at St. Paul Island shows that its lowest temperature 

came in April. The greatest daily range in temperature lasts from September 

to March, thus including the periods of greatest cold. The season of least daily 

ranges lasts from May to October, with a warm season during- June, July, and 

August.

Frosts. The last frosts occur about the end of May and the fall frosts come 

toward the middle of September; thus the growing season for plant life is scarcely 

one hundred days in length.

Sea ice. The sea in the vicinity of St. Lawrence Island is covered by ice from 

the first week in No\~ember until the end of April. The harbors along the coast 

do not open as early at Carmel Mission clear water not appearing before the first 

week in May and at St. Michael Harbor usually not before the end of the first 

week in June.

ARCTIC COAST CLIMATIC PROVINCE.

Rainfall. The precipitation along the Arctic coast of Alaska is probably the 

smallest in amount of any recorded there, averaging between 6 and 7.50 inches in a 

year. Most of the scanty winter precipitation is in" tffe f'd'fm"6f*ratter""M-K&=fiRt'iaed--- 

snow, which drifts very badly under the influence of the storm winds of the season 

and is therefore very hard to measure accurately. On account of this low amount 

of moisture the climate may be classed as arid. It is comparable to that of the 

upper San Joaquin Valley in California and the Nevada-Utah deserts. The number 

of days with a measurable amount of rain is, of course, also the lowest for Alaska.

The greater portion of the scanty annual rainfall comes between July and 

December, the months from July to October generally having the greatest monthly 

totals (PI. XIX). Another peculiarity about the rainfall here is the relatively great 

contrast between the small amount in December, January, and February and that 

which comes during July, August, and September. The former have monthly totals 

of 0.03, 0.05, and 0.19 inch; the latter have totals of 1.34, 1.02, and 1.48 inches, 

respectively. A study of the table on page 166 shows that most of the fall of any month 

may occur in one or two days only, leaving all the rest of the month without a measurable quantity to its credit. Indeed, cases are on record where the whole month's rain 

fell in less than one day. On the other hand, it has happened at Point Barrow that 

January, April, and May have passed without any rain or snow falling. The dry-
154 GEOGEAPHY AND GEOLOGY OF ALASKA.

ness of this province is still further shown by the table on page 168, from which it 

appears that the average number of rainy days per month is thirteen or lower. 

In no other province except the interior does the average number of rainy days fall 

below fifteen except during the dry season. Here in the rainy season the highest 

number of rainy days on record is eighteen, reached once. Four times the maximum 

number reached fifteen, while the minimum has been 0 four times and 0, 1, or 2 

fourteen times.

Temperature. The extreme annual range of temperature in the province 

(p. 158) is very nearly the same as that of the Bering Sea coast, but the extreme 

is here subject to much greater fluctuations. Except at Kikiktak, whose maximum temperature is 81°, the summer temperature, shows distinctly the influence 

of the cold waters bounding this province on the north. The highest temperatures recorded at Point Hope or Barrow do not exceed 65°, a maximum which 

is also found on Bering Island. The maxima occur only during July and 

August. On the other hand, the minimum temperatures, while low, are not as 

severe as in the mountains to the south. The extreme low temperatures of the 

province have probably not gone lower than 55°, a temperature which has been 

equalled or exceeded at nearly every one of the interior stations. Evidently 

even the icebound Arctic Ocean exerts a moderating influence upon the winter 

temperatures of its coast. For the same reason the range in temperature is no 

greater at these higher latitudes than it is reported to be along the Bering Sea 

coast. While considering these minimum temperatures it is interesting to find that 

only in June, July, August, and September has the minimum temperature failed 

to fall below 0° F., while August at Point Hope is the only month in which the 

temperature has not fallen below 32° F. From these records it is clear why 

every month in the year seems to be subject to frost in this province.

The minimum temperatures and the greatest daily ranges of temperature 

^cur_djwin^_JaftuarFy r-Feb«iar-y, andMarch. The daily range decreases until 

the end of May, when it suddenly drops to its minimum, which it holds during 

June, July, and August. The season of minimum daily range at Barrow, however, seems to come from July to September, one month later than at the two 

stations on the more western coast of the province.

Frosts. Unfortunately the growing season has not yet been carefully recorded 

in this region. Probably it does not begin before the end of June and ends on 

or before the middle of September. In 1902 a killing frost occurred at Barrow 

at the end of August, and if this happens every year or two the growing season 

there is likely to prove too short for human needs in spite of twenty-four hours 

of sunlight during the summer months.

INTERIOR CLIMATIC PROVINCE.

Temperature. The geographic position of the interior province leads one to 

expect here the greatest extreme annual ranges of temperature and the greatest 

mean annual ranges. Indeed the extreme ranges here are from 120° to 162° F., 

and generally they are not less than 133°. The extreme monthly ranges naturally
CLIMATIC FEATUBES. 155

cover a smaller interval: the greatest of them were 112° and 110° in January, 

February, and March at Eagle and Tanana, respectively. It is probable that 

even at these stations such monthly ranges are rarely attained in any one year. 

The smallest extreme monthly ranges may be expected during -June, July, and 

August, and even these greatly exceed the ranges which characterize these 

months in the other provinces of Alaska.

A brief examination of the table of temperatures of the interior province 

(p. 158) shows that extremely high temperatures are not characteristic. The 

maximum temperature recorded by properly sheltered instruments has not risen 

above 90° in the great Yukon basin, and the temperature of 91° at Copper 

Center, on the Copper' River Plateau, is the highest that has been reported from 

any of tho voluntary observing stations of the United States Weather Bureau. 

The writer is not unmindful that Dr. W. H. Dall makes the following statement:

"At Fort Yukon I have seen the thermometer at noon, not in the direct rays of 

the sun, stand at 112 , and I was informed by the commander of the post that 

several spirit thermometers, graduated up to 120°, had burst under the scorching 

sun of the Arctic midsummer.' 1 "

This passage leads one to infer' that the temperature at Fort Yukon has 

been known to reach 120° F., but the writer doubts if such, an inference is 

justified by our knowledge of the facts concerning the exposure of the thermometers which are reported to have burst under the heat. Since the Weather 

Bureau has been sending standard instrument shelters into the Alaska interior 

and has been receiving records from registering instruments exposed in them, 

no such temperature for the air as 112° has ever been reported. That it grows 

very hot in this province no one may deny. Doctor Dall, in the same book 

(loc. cit.), has characterized the summer heat thus:

" In midsummer on the upper Yukon the only relief from the intense heat, 

under which the vegetation attains an almost tropical luxuriance, is the brief space 

during which the sun hovers over the noftiierh~hoTr2O'hrand~^he' voyageur in his 

canoe blesses the transient coolness of the midnight air."

The air temperatures of the interior have sometimes been closely approximated by maximums in the Pacific coast province, but it is not probable that 

they are often even approached there, and surely the days as a whole must be 

much more bearable.

The minimum temperatui'es in this province fall much below those usually met 

with in any other portion of Alaska. The lowest recorded is 80° at Fort Reliance 

in January and the highest absolute minimum for any station is 49°. which was 

observed at Camp Davrdson and Camp Colonna, on the international boundary. 

With the exception of these two stations the extreme minima decrease rather 

regularly as the Bering Sea coast is approached. The table shows that the great 

range in temperature which is experienced in the interior is due to the very lowwinter temperatures rather than to very extreme summer ones.

Growing season. The growing season in the interior seems rather short in 

number of days, but when one remembers the length of time that the sun remains

a Dall, W. H., Alaska and its Resources, Boston, 1870, p. 4:-i7. 

17211 No. 45 06 11
156 GEOGRAPHY AND GEOLOGY OF ALASKA.

above the horizon and the consequent increase in the number of hours of insolation, 

the luxuriant and rapid growth of vegetation already referred to seems not so 

remarkable. The records at Camp Colonna show that the growing season during 

1889-90 lasted from the end of April to the middle of October, making about one 

hundred and fifty days free from dangerous frosts. At Camp Davidson the record 

is more accurate and shows a much shorter season. Here the last killing frost 

occurred between the 3d and 27th of June, and the first killing frost came on August 

13. At Eagle the records from 1883 to 1885 show that the last spring frost comes 

about May'35 arid the first fall frost about the end of August, thus allowing a 

maximum growing period of perhaps one hundred and ten days. Fort Reliance has 

had frosts occur as early as the middle of August, with killing frosts before the end 

of September. Fort Yukon reports killing frosts by the first of September, and 

Holy Cross Mission, in the western interior, shows the average date of the last 

spring frosts to be the middle of May, and the first frost in the fall to happen by 

the end of August, or even earlier, so that the growing season there seems to last 

scarcely ninety days. In general, it may be concluded that the period of growth for 

the more tender vegetation of the interior province rarely exceeds fifty days in the 

eastern part, but increases in length up to perhaps one hundred and twenty days as 

the western coast is approached, lasting from the middle of June to the middle of 

August.

Rainfall. The generally scanty rainfall of the interior is outclassed only by 

that of the Arctic coast. The most complete records of this element come from 

Eagle, where an average rainfall of 11.35 inches for the year has been observed. 

The fragmentary records from other interior stations indicate that Eagle probably 

has the smallest rainfall of the interior with the exception of Fort Reliance. 

As a whole, it is clear that the rainfall is least in the extreme eastern portion of 

i(,'e and_incre_ases_ westward.,ap, to a maximum of probably not much over 

25 inches in the year. This range in precipitation is also characteristic of that 

portion of the United States which lies between the Sierra Nevada and the Rocky 

Mountains north of the latitude of Salt Lake City. Similar conditions also prevail 

over northern Europe and north-central Asia, as well as most of Canada lying north 

of the Great Lakes.

The intensity of the rains in this province is much less than that found in the 

Pacific coast province, as is brought out in the low maximum rainfalls for any 

twenty-four hours. These rains rarely attain as high an amount as '2 inches, and 

most of the stations, particularly in the eastern and central portions, show only 

half of this amount or less. The variation in the maximum amount of rain 

observed in one day is considerable, ranging from 4.1 inches at Kolmakof 

down to 0.07 inch at Fort Reliance. This shows that these maximum falls in a 

day, like the average annual and monthly precipitation, decrease as distance from 

the coast increases.

The season of heaviest monthly rainfall lasts from June through August over 

the eastern portion of the province, and from August to November in the central 

and western areas. The largest number of rainy days occur during August and September, the average rising to sixteen or eighteen. The rain which falls during these
CLIMATIC FEATURES. 157

months comes in the form of heavy showers and rarely stretches itself over more 

than twenty-four hours. The months of Februar}' and May show the lowest 

number of rainy days, the averages being from six to eight, and the season with 

the smallest maximum twenty-four hour rains seems to be from October to 

June. The incomplete character of the summer records in this province prevents 

any accurate study of the summer conditions, and the above summary may need 

ver}- decided revision when better records shall be obtained.

River ice. The opening and closing of the, streams of the interior is best 

presented in the tabular statement on pages l74-17ti.

GENERAL CLOIATOLOGIC TABLES.

The following tables present in a compact form some of the results of observations on temperature, frost, rain and snowfall, and the movements of river and 

harbor ice at forty-six stations in Alaska. In these tables the stations have been 

grouped by geographic provinces, so that the observations relating to each province 

ma}' all be under the eye at one time. The geographic coordinates of each station, 

the organization or organizations under which the observations were made, and other 

general information are given in the table on page 138, where the stations are 

arranged in alphabetical order.
158 GEOGRAPHY AND GEOLOGY OF ALASKA.

Extreme temperatures and

Stations.

Pacific coast.

Orca. ...............................

Kodiak (2) (Woody Island) ........

Alaska Peninsula.

Aleutian and Commander islands.

Kiska Island .......................

Bering Sea coast.

Bering Sea islands. 

Gambell (St. Lawrence Island) ....

Arctic coast.

Point Hope (mission at Tikira) .....

Interior stations.

1 Circle

Copper River Plateau.

Ja 

Max.

°F.

47* 

47* 

52 

50 

44 

42 

51* 

48 

43 

45 

45 

38 

51 

49

46

47

47

52 

45 

35 

42 

37

40 

42 

41 

44 

43?

32f 

40*

44 

23 

20

'20 

25 

23 

28 

19 

19 

34

36 

41

43

nuary. 

Mill.

°F. 

6* 

_ 4*

_ 9 

_ lt

4 

 4 

 2* 

20 

5 

-U 

-40 

-27 

i

 5 

 27

- 9 

12

16 

20 

17 

17 

3

-27 

-41 

-39

-33

-27 

13

<-50? 

-34* 

-49

-80

-IS

-66 

-Id 

 68 

-76 

63

-62 

-39 

-55 

-48 

-68

R.

°F. 

41 

51 

54 

54 

40 

46 

53 

28 

38 

59 

85 

65 

52 

54

73

56 

35

36

25 

18 

25 

34

67 

83 

80 

91 

76

59 

27

94 

57 

69

100 

74 

98 

83 

68 

87 

110

85 

74 

96 

87 

101

February. 

Max. I Min. R.

°*\

45* 

58* 

50 

50 

50 

44 

54* 

47 

46 

42 

45 

49 

52 

58

51

51 

45

51 

46 

44 

41 

43

39

35 

40 

36

35* 

39

34 

6* 

24

27 

21 

38 

28 

35 

42 

38

29 

37 

41 

36 

42

°F. 

23* 

2* 

-10 

- It 

4 

- 9 

- 3 

16 

8 

-12

-17 

-10* 

4

-38

6 

9

J2

15 

17 

3

 SO

-29 

-6S

-31 

_ j

-U 

-53

-72

74

__ ft ft

60

11

-60 

-63

-49 

-44

°F. 

22 

56 

60 

54 

46 

53 

57 

31 

:i8 

54 

77 

66 

62 

54

89

63 

39

60 

34 

29 

24 

40

69

64 

95

88

66 

40

79

47 

77

99 

60 

112

83 

82 

90 

98

89 

90 

98 

85 

86

March. 

Max. Min.

°I-\ 

59* 

54*

50 

61 

63

65 

45 

57 

52 

52 

58 

fi4 

55

55

53 

45

51 

46 

43 

41 

39

46 

62

44 

43

35

43*

40 

38* 

26

45 

30 

56 

38 

33

46

44 

46 

47 

49 

44

°*:

- » 

-10* 

_ 9 

10 

 ,~, 

-10-! 

- 1 

27 

2 

- 8 

-34 

- 9 

11 

5

-36

- 3

r, 

21 

18 

11 

1

-70

on

36

-SI 

9

-36 

-39

-36

-30

-eg

AV

OO

An

-33 

-43

55

-35 

-36?

R.

°F. 

61 

64 

54 

40 

66 

73 

06 

18 

55 

60 

86 

67 

53 

50

91

04 

48

4t> 

15 

25 

30

38

61 

132

83 

79

66

52

76 

77 

77

81 

60 

112 

93 

81

84

77 

89 

102 

84 

80

Max.

°f. 

60* 

04* 

63 

63 

61 

61 

70* 

54 

64 

52 

58 

59 

61 

59

59

65* 

49

59 

50 

50 

52 

40

48 

47

46

42* 

49*

40 

35 

32

59 

46 

59

48 

51

53

50 

46 

50 

53 

49

\pril. 

Min. R.

°F. 

33* 

24* 

15 

13 

28 

16 

19* 

27 

25 

2

4 

I

20* 

9

11

4 

14

18 

21 

21 

26 

1

8 

15

-26 

-24

-18 

-10

-27

-32 

-35

-10

-12

-22

Oo

-14 

-15

-23 

25

-31

-16 

-12

°r.

27 

40

48 

50

45 

51 

27 

39 

50 

54 

58 

41 

50

48

61 

35

41 

29 

29 

26 

39

40 

62

72 

79

60 

59

67 

67 

67

69 

51 

71 

70 

79

67

78 

71 

81 

69 

61

NOTE. Italic figures denote minimum observed for station; heavy faced, maximum observed.
TEMPERATURE. 159

ranges in Alaska Territory/.

.\"0.

1

2 

3 

-1

ti

8 

9 

10 

11 

12 

13 

1-1

15 

l(i 

17

18

19 

20 

21 

22 

23

24 

25 

26 

27 

28

29 

30

31 

32 

33

3-1 

35 

3(1 

37

38

-10 

41 

-12 

-13

44 

45 

46

47

Stations.

Pacific coast. 

Fort Tongass ... ... ...............

Skagwav . . .

Xueliek {Fort Constantine) .......

Fort Liscnm

Kenai ......

Alaska Peninsula.

Morzhovoi . . ..............

Aleutian and Commander islands.

Atka Island ..... . .......

Kiska Island .. ........ .... ....

Attu Island.. ......... .............

Bering Island ........ . ..........

Bering Sea coast. 

Fort A lexander ........... .......

Carmel Mission (Nushagak) ........

Bethel Mission .....................

St. Michael.......... ..............

Omalik (mine) .....................

Bering Sea islands. 

Gam bell (St. Lawrence Island) .....

Arctic coast.

Point Hope (mission at Tikira)..... 

Utkiavi (Cape Smyth) .......... ..

Interior stations.

Camp Davidson

Rampart ........... ...............

Auvik .......................

Kolmakof . . ....

Copper River Plateau.

May.

Max.

°/.'. 

70* 

78* 

76 

71 

69 

79 

80 

58 

64 

62 

63 

68 

62 

71

63?

67* 

>51?

60 

65 

50?

56*

67 

65

56 

63

45 

52*

61 

55*

42

76

74 

82 

78 

68

Min.

°F.

38* 

35* 

24 

26 

29 

4)5 

28 

30

25 

20 

22 

20* 

20

20?

1-2

<25?

24 

24 

37?

23 

23

- 3 

16

3 

19

-15 

-14

16

8 

10 

6 

15

72 11 

22

71

67

65

72

14 

- 4 

14? 

19

K.

°F. 

32 

43 

52 

45 

40? 

54 

52 

28 

36 

37 

43 

46 

40 

51

43

55 

26?

36 

41 

13

June.

Max.

°/-'. 

75* 

86* 

76 

82 

80 

90 

80* 

70

79

79 

82 

76 

82

83

Min.

°P. 

43* 

38* 

33 

38? 

3(i 

34 

33 

39 

35 

32 

26 

33 

34 

37

29

R.

°F.

32 

48 

43 

44 

44 

56 

47 

31 

42 

47 

53 

49 

42 

45

54

71 , 15 , 56

68 

72 

70

33 1 61*

60 78

42 81

59

47

42 

33

76 

67 

56

60 

66

72

53

61

64 

53 

69

58 

47

34 

28 

35

31

32? 

35

66 22

62 

63*

72 

58* 

61

15 

31

27 

21 

18

84 ! 30 

87 26 

84 ' 32 

79 26

34 

44 

35

30

46 

46

44

47 

32

45 

37 

43

54 

61 

52 

53

81 24 ! 57

July.

Max.

°F. 

91*

82* 

84 

88 

86 

92 

87* 

69 

80 

77 

82 

83? 

82 

82

78

79

78

78 

76

67

63

69

78

77

59 

59

81 

56* 

65

87 

82 

88 

85

Min.

°F. 

52* 

44 

38 

38 

40 

39 

35 

47 

33

30 

38 

40* 

40

31

37

37?

37 

35 

38

36

36 

38

33

30 

35

32 

26

27

35 

31 

39 

36

R.

°F. 

39 

38 

46 

50 

46 

53 

52

53 

45

45 

42 

42

47

42 

41?

41 

41 

29

27

33

40

44

29 

24

49 

30

38

52 

51 

49 

49

83 31

67 

94

35 

38

52

32 

56

A 

Max.

°F.

81* 

84 

81 

82 

71 

80 

82* 

70 

78 

70 

73 

73 

75 

77

86

62 

75* 

68

78 

72 

64 

66 

63

78

ugust.

Min.

f.

47* 

43 

36 

38 

39

09

39 

46 

40 

30 

28 

31 

41 

41

32

42 

33

42

36 

39 

38 

38 

37

42

R.

I' .

34 

41 

45 

44 

32 

48 

43 

24 

38 

40 

45 

42 

34 

36

54 

20 

42 

26

42 

33 

26

28 

26

36

69 32 , 37

59 

56

67 

62* 

59

74 

80 

90

25 

40

26 

36* 

26?

34 

16

41

26 

33?

31 43 

24 56 

26 , 64

79

65? 

75? 

76?

(75)

85

28 51 

36? ....

40 

30 

29? 

17

28

25 

45 

47 

58

57
160 GEOGBAPHY AND GEOLOGY OF ALASKA.

Extreme temperatures and ranges

No.

1 

2

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

IS 

14

15 

16 

17 

18

19 

20 

21 

22

23

24 

26

26 

27

28

29 

SO

31 

32 

S3

34 

SB 

36 

87 

SB 

39 

40 

41 

42 

43 

44 

45 

48

47

Stations.

Pacifte coast.

Sitka ...............................

Kodiak(l) ....................

Alaska Peninsula.

Mine Harbor (Herendeen Bay) ....

Aleutian and Commander islands.

Attu Island. ......... ...............

Bering Sea coast.

St. Michael .......................

Bering Sea Wanda. 

Gambell (St. Lawrence Island) .....

Arctic coast.

Point Hope (mission at Tikira) .....

Interior stations.

September.

Max.

0 F. 

67* 

73 

69 

85 

66 

76 

74*

74 

64 

65 

70 

68? 

72

75 

02 

72* 

61

68 

62 

62

58 

59*

71

09

50 

54

63 

60* 

52

67 

66

78

84

Mln.

0 F. 

88* 

38* 

27 

SI 

34 

SO 

32

SI

25 

36 

25 

36 

36

22

32 

10

36

33 

34 

29 

86 

SO

21

21

R.

°F. 

29

35 

42 

54 

31 

46 

42

43 

39

49 

45 

32

36

53 

30 

62 

25

35 

28 

33 

22 

29

50

48

21 29 

SI 23

11 ^ 62 

29 SI 

20 X

12 55 

14 52

8 70 

2 ' 82

r>?'> V

72

Kulato (St. Peter Mission) .......... ........

Anvik. ............... ............

Copper River Plateau.

66 

68 

68? 

68

68

12 ' 60

23 ....

11 

11 

24

5

19

55 

51

44 

83

49

October.

Max.

0 F. 

68* 

67* 

" 60 

66 

65 

60 

67* 

66 

59 

63 

60 

61 

59 

66

56

60 

51

62 

54 

64 

49 

51

65

Mln.

0 j?

37* 

31* 

25 

20 

23 

16 

25 

22 

25 

18 

-10 

10 

SO 

22

0

15 

28?

26 

28 

24 

SO 

18

9

BO 

8G?

44f 

56*

45 

39 

42?

55 

52 

68 

(38) 

34 

45 

54 

53 

47 

51 

57 

50 

59

«i

6

12 

26

!

-14

_ -1

22

-11

4

«)O

(-12)

- 6 

-12 

-21

-13 

-18 

14

14

R.

°F. 

21 

36 

35 

46 

42 

44 

42 

43 

34 

35 

70 

51 

29 

44

56

45 

23

36 

26 

30 

19 

S3

56

51 

38?

32 

31

59 

40 

04?

66

48 

96 

50 

40 

57 

75 

62 

60 

69 

71 

55 

73

67

November.

Max.

0 F. 

51* 

53 

53 

60 

56 

51 

59* 

45 

48 

45 

44 

44 

53 

54

46

59 

50

54 

49 

47 

46 

44

47

35 

43 

82?

86 

43

38 

34 

SO

3(1 

34 

39 

28 

35 

28 

3(1 

15 

28 

41 

44 

41 

39

32

Mln.

0 j?

32* 

4* 

1 

1

10

7 

5*

10 

11 

0

- 2(1 

13 

15

27

14 

23

19 

22 

18 

25

7

- 12

-38 

 22

29

 19

18

-21

Of!

-86

62

-52 

-39 

-52 

-53

-36 

35

-25

34

46

R.

°F. 

19 

49 

52 

61 

46 

44 

54 

35 

37 

45 

70 

31 

38 

45

73

45 

27

35 

27 

29 

21 

87

59

73

65 

61?

55 

25

?

on

66

86 

69 

91 

SO 

71 

80 

89 

59 

64 

76 

69 

75 

80

78

December.

Max.

° F. 

47* 

52* 

54 

45 

54 

67 

59 

41 

48 

41 

45 

49 

50

* ) 

46

50 

46

50 

45 

42 

44 

41

43

35 

45

33+ 

42

29 

28* 

14

34 

17 

39 

32 

17 

80 

17 

25 

31 

25 

48 

42 

41

34

Mln.

° 7''. 

24* 

3*

1 

1

8

_ 4

7* 

13 

7 

-IS

-W 

21

- 6

-U

-26

- 2

10

12 

IS 

18 

22

 1

29

-51 

-43

29

-16? 

4

40

-86

r.K

-1,9

-68

-53

-43 

-63

-64 

-54 

44

-50

-6St 

-53

-es

R.

°F. 

28 

65 

63 

44 

46 

61 

52 

28 

41 

54 

88 

70 

66 

61

72

52 

36

38 

8!) 

24 

22 

42

72

86 

88

49? 

38

69 

64 

69

103 

66 

107 

86 

60 

83 

85 

89 

85 

69 

98 

95? 

94

87
TEMPEKATUKE. 161

in Alaska Territory Continued.

No. Stations.

Pacific coast.

Fort Tongass.. 

Fort Wrangell.

Killisnoo.. 

Juneau (1)

Juneau (2) (wharf) 

Skagway ...........

Sitka ........................

Nuchek (Fort (,'onstantine) . 

Orca.........................

Fort Liseum. 

Kenai .......

Tyonok............................

Kodiak (1) ........................

Kodiak (2) (WoodyIsland) .......

Alaska Peninsula.

Ugashik ...........................

Mine Harbor (Hercndeen Bay) ... 

Coal Harbor (Unga Island)........

Morzhovoi.........................

Aleutian and Commander islands.

Unaiaska..........................

Atka Island .......................

Length of 

record.

Years. Mos.

Kiska Island ......................

Attu Island........................

Bering Island .....................

Bering Sea coast.

Fort Alexander ...................

Carmel Mission (Nushagak).......

Bethel Mission ....................

St. Michael........................

Omalik (mine)....................

Bering Sea islands. 

Gambell (St. Lawrence Island)....

St. Paul Island ....................

Arctic coast.

Kikiktak (Friends' Mission) ......

Point Hope (mission at Tikira)....

Utkiavi (Cape Smyth) .............

Interior stations.

Fort Beliance .....................

Camp Davidson ...................

Eagle (Fort Egbert)...............

Circle.

38 | Camp Colonna . 39 I Rampart ......

40 I Tanana (1) (Fort Adams).

41 Tanana (2) (Fort Gibbon).

42 Nulato (St. Peter Mission).

43 Anvik ..

44

..............

Holy Cross (mission) .. 

Ikogmut...............

Kolmakof...................

Copper River Plateau. 

Copper Center................

44

Dates of records.

June, 1868, to Sept., 1870.

JunetoAug., 1868; Apr., 1869, to Sept. 26,1870; Feb., 1875, to June

14,1877; Aug. 25 to Dec., 1881; Feb. to Mar., June to Aug. ,1882. 

May, 1881, to Feb., 1885; June to Oct., 1885; Mar. to Dec., 1886;

Jan. to Mar. L Sept. to Dec., 1888; Jan., 1889, to Dec., 1902. 

June, 1881, to Mar., 1882; May, 1883, to Oct. 1884; Nov. 13, 1889,

to Jan., 1892; Nov. 16,1894, to Jan., 1895; June 17-Sept., 1895;

Sept., 1896, to Feb., 1897. 

Dec., 1898, to Dec.,1902. 

Nov., 1898, to July, 1899; Sept., 1899, to Aug., 1900; Sept., Oct.,

1901; May to Dec.. 1902. 

Nov., 1867, to May. 1877; Apr., 1881. to Sept., 1X87: July, 1898, to

Feb., 1899; May, 1899, tol)ec., 1902. 

Oct., 1883, to Aug. 31, 1884. 

June, 1899, to Mav 1900; Oct. 7, 1900. to Mar., 1901; July, 1901, to

Mar., 1902; Sept. 17 to Doc., 1902. 

Jan., 1901, to Dec., 1902. 

May to Aug. and Oct. to Dec., 1899; Jan., 1900, to Dec., 1902.

(Min. also Jan., 1885. to May, 1886.) 

Nov., 1898, to Dec., 1902.

NOT., 1895, to Aug., 1896, and Nov., 1898, to Nov. 1899. 

Jan., 1900, to Dec., 1902; missing are Sept., 1900. and Oct., 1902.

Nov. 11, 1833, to Dec. 13, 1885; Aug., 1883.

Aug. and Sept., 1902.

Sept., 1889, to Sept.. 1890; Aug. 1891 to Sept., 1902.

Nov., 1881, to May 7, 1882; July, 1882, to May 24, 1883.

10 July, 1881, to Apr., 188S.

16 I May 7, 1879, to Aug., 1879; Oct., 1881, to May 12, 1885; May, 1886

to Aug., 1886. 

11J- 1 May 13, 1X85. to Apr. 30, 1886.

9 Aug., 1880, to Apr. 30. 1X81. 

24 June, 1882, to May, 1886.

Aug., 1881, to June, 1883; June 15, 1884, to June 12, 1886. 

1902.

Nov., 1885, to Feb., 1886.

Aug., 1877, to Dec., 187X; July, 1880, to June, 1886; Oct., 1899, to

July, 1901. 

12 Jan. 20 to May, and Oct. 18 to Dec., 1884; Jan. to Apr. 16, 1885.

32 ! Oct., 1894, to Sept., 1897; Nov., 1898, to June, 1899; Oct., 1901, to

Sept., 1902. 

31 Oct., 1869. to June, 1X70; May 1-15, 1878, to May, 1879; June, 1881,

to May, 1883.

I 9 ' Sept. r>. 1897, to Mav, 1901. 

12 Aug.. 1X94, to July, 1896. 

22 i Oct. 17, 18X1, to Aug. 6, 1883; Sept., 1901, to Aug., 1902.

18 Sept., 18X2, to May 8, 1883; Sept. 17, 1885, to May 29,1886.

13 May, 1890, to May, 1891.

58 Oct.. 1882, to May 9, 1883; Aug. 22, 1884, to May 12,1885; Aug. 16,

1885, to May 19,1886; Aug. 15,1899, to Dec., 1900; Nov. andttcc.,

1901; Feb. to Dee., 1902. 

Dec. 15, 1896, to June, 1898; Nov., 1898, to Sept., 1S99; July, Aug.,

1900.

10 Oct. 13, 1889, to July 14, 1X90. 

6 I Oct. 1 to 23 and Nov., 1900, to Feb., 1901; Jan., 1902; (22?) is for

Sept. 25 to 30, 1901 only. 

Aug.. 1882. to May 22, 1883; Sept., 1883, to Mar., 1884; Aug. 18,

1885. to May, 1886. 

13 Aug., 1901, to May, 1902; Oct. to Dec., 1902. 

12 Oct., 1894, to May, 1895; Jan. to Apr., 1896. 

28 Sept., 138.;, to .May, 1885.

20 Oct., 1893, to June, 1894; Sept., 1894. to Aug., 1901. 

2o Aug. 18,1883, to May, 1884; Aug. 16 to 31, and Nov. 9,1884, to May,

1885; Sept., 1885, to May, 1886. 

30 I Aug., 1883, to Aug. 8, 1884; Aug. 25. 1885, to May 14, 1886.

5i' July 18 to Dec. 31, 1902.

* Indicates record from observations at la, 2p, f Indicates record from observations at 8a, Sp.
162 GEOGRAPHY AND GEOLOGY OF ALASKA.

Mean precipitation, including melted wurw, and the mean number of

January. February. March. April.

No. Stations. 

Days.

1

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14

15 

16

17 

18

19 

20 

21 

22 

23

24 

25 

26

27

28

29 

30

31 

32 

33

34 

35 

36 

37 

38 

39 

40 

41 

42 

43 

44 

45 

46

47

Pacific coatt.

Juneau (1) ........................................... 18. 1

Sitka .................................................: 16. 8

Kodiak (1).. ......................................... 1C. 0

Alaska Peninsula. 

Ugashik .............................................. 14.0

Mine Harbor ( Herendeen Bay }...................... ........

Aleutian and Commander islands.

Bering Sea coast.

Bethel Mission ....................................... 6

Bering Sea iskmds.

St. Paul Island. . ..................................... 21. 0

Arctic coast.

Interior stations.

Circle ................................................ '........

Holy Cross (mission) ................................. 8. 0

Copper River Plateau.

Mean 

total.

12.92 

0. 07 

5 98

10. 61 

8.77 

0. 90 

12.17 

2J.OV 

12. 66 

9.67 

0.78 

2.15

4.82

1.44

S. 96 

7.51

1J.94

9.05 

2.06 

5. 29 

0.70

3.19

1.98

0.85 

0.40

0.05 

0.19

1.00

0. 59 

0.43

0.68

1.69

0.68 

1.33

1.02 

1.29

Days.

21. 5 

20. 0 

14.9 

11.2 

11.7 

2.5 

15.9 

8.0 

8.3 

5.0 

4.4

Mean 

total.

10.79 

8.11 

4.96 

4. fir, 

4.38 

0.57 

7.47 

9. 15 

6.40 

1.04 

0.70 

0 65

14.0 4.44 

14. 7 4. 26

7. 0 0. 49

d 13. 0 

6.5

21.0 

15. 5 

7 

15 

13.0

7.5

6 

5.5 

3

8 6

2.94

9.82 

6.47 

0.9S 

3.01 

1.59

1.07

0.24 

0.32

15.0 1.59

1.5 

5.3

6.5 

14 

5.8

16

8.6

0.03 

0.36

0.76 

0.86 

0. 55

2.08

Days.

17. 5 

12.6 

15. 0 

18.7 

14.2 

3.0 

18.0 

21.0 

11.0 

14.5 

7.4 

4.5

11.0 

U.I

ltf.0

14.0 

4.0

 13.. '2 

12. 0 

9 

22 

12.5

14.5 

11

7.4 

3.5

11.0

16. 5

3.0 

6.6

4.5 

6 

4.8

12 

...

0. 85 18. 0

7. 0 0. 91 

6. 0 0. 37 

6.6 ........

7. 3 0. 57 

6.0 0. »

12. 5 

15.3 

10.6 

14.7 

14.0

Mean 

total.

8.21

-2.89 

4.04 

6. 62 

4.62 

0. 64 

6.70 

18. 02 

11.08 

5. 54 

0.97 

0.71 

4.17 

5. 21

1.04

4.20 

2. 20

7.76 

5. 22 

3.40 

2. 60? 

0.91

3. 06

0. 52 

0. 15

2.45

0.49 

0.23

0. 23 

0.22 

0.39

Days.

19.0 

16.0 

11.0 

15.0 

17.0 

10. 5 

16.2 

18.0 

I> 22. 0 

9.0 

6.4 

4.0 

14.0 

10.5

14.0

13. 2 

5.0

24.8 

15.2 

11 

16 

11. fi

10. 5

8

7.8

10.8 

15.5

5.0 

6.6

2.5 

9 

8.6

0.81 4

0.68

1.46

1.44

1.32 

1.18

3.5

>2 

7.6 

7.4 

11.0 

9.3

Mean 

total.

9.57 

4.11 

« 3. 50 

5. 25 

7.04 

2.39 

5. 61 

16. 92 

ft 16. 85 

4.50 

0.83 

0.88 

2.92 

2. .93

1.14

5.12 

1.47

9.69 

6.66

2. 25

1.13 

1.67

........

0.36 

0.07

1.87

0.27 

0. 32

0.07 

0.61 

0.76

0.12

0. 44

>o.ie

0.54

0.63 

0.88

a. For 13 years only. !> For 1900 only. 

NOTE. Italic figures, minimum for year; heavy faced, maximum for year.

rf For 8 years.
PRECIPITATION. 168

days with 0.01 inch or more precipitation, for eacli month and the year.

No.

1

 2 

3

4

5 

6

8 

9 

10 

11 

12 

13 

14

15 

1C

17 

18

19 

20 

21 

22 

23

24 

25 

26 

27

28

29 

30

31 

32 

33

34 

35 

»6 

37 

38 

39 

'10 

41 

42 

43 

44 

45 

46

47

Stations.

Pacific const.

May.

Days.

18.6 

12.3 

1C, 7

Sitka.... .............................................

Nuchek (Fort Constantine) . . .......................

Fort Liscuin . . ... ........ ...... ........

Kodiak (2) (Woody Island! ..........................

Alaska Peninsula.

Morzhovoi .............................. ............

Aleutian and Commander islaml*.

Atka Island. ..... ......... ..... ....

Attn Island ..........................................

Bering Island. ... .... .....

Bcriny Ken ciiast. 

Fort Alexander ....................... . .........

Carmel Mission (Nushagak)... ....... ..............

Bethel Mission .......................................

Omalik (mine) ...................... . ......... .

Jlei'inti Sea island* 

G-ambell (St. Lawrence Island).......... ............

St. Paul Island.................. ............. . .

Arctic matt. 

Klkiktak (Friends' Mission). ............ .......

Point Hope (mission at Tikira)......... .............

Interior ftatioiia. 

Fort Reliance ................ ....

Camp Davidson. ............. ....

Eagle ( Fort Egbert ).................

Circle............ . .

Camp Colonna . . . . ..... . ....

Ham part ........................... . .

Tanana (1) (Fort Adams) ............................ 

Tunana (2) (Fort Gibbon) . ......

Nulato (St. Peter Mission)............. .....

Anvik.. .................... . .....

4.7 

1(1. 1 

18.5 

ft 20. 0

3.7 

14.0 

15.0

Mean 

total.

7.70 

3.71 

3.38 

7.36

4.28 

0.77 

4.11 

18.92 

I> 13. 70 

2.26 

1.01

0. .',/, 

4.97 

5.21

C 1 fill

11.8 

< 8 0

'2.U9 

« 5. SB

15.8

6?

14.2

10

9.1 

2

21.3

3.5

6. G 

6.0

7

6.14 

3. 94?

0.96

1.30

1.27 

0.0?

2.12

0.21 

0. 25

0. 69?

0. 56 

0. 76

4 0.60

June.

Days Meim 

J - 1" total.

10. 3 i;. in;

13. 7 3. 56 

9.9 , 2..16

12.7 

5.0 

13. (i 

10. 5 

ft 11.0 

8.0 

5,1

4.2 

9.0

8.7

11.5

10.4

11.2 

13.6 

10

12. 5

10.4

8?

3.5 

9.0

11

9.5 

4 

5

12.0 1.51 ........

4 0.36 

7. 0 0 63

Holy Cross (mission).. ............................... 5.1 ......... 8.7

Kolmakol'........

3. 09 

0. 60 

3.31 

/,. 11 

l> 4. 59 

O.fiS 

0.73 

0.61 

2.11 

3.13

1.14

«.«

4.94 

4. 50 

3.38

1. 67

1.88 

0.40

1.45

Ji 

Days.

16.6 

15.8 

11.7 

15.5

11.0 

5.7 

14.9 

18.5 

11.0 

14.5 

8.9 

8.2 

7.0 

11.3

25. 5

10.6 

/5.0

14.8 

12. 6 

12

15. 7

16.7 

14

13.6

s n

1. tit

0. 51 

0.47

2.21 

1.36 

0. 54 

0.27

10.0

8.0 

11.6

14 

13.0

8.5

Copper River J'latcatt. 

Copper Center ....................... .. .. .

12.0

iy.

Mean 

total.

10.58 

3.69 

' 4.19

3.96 

1.73 

3. 55 

9. 93 

It. it, 

4.21 

1.69 

2.09 

0.80 

4.02

2.90

2.81 

/ 2. 67

2. 91 

5.28 

6.39

2.46

4.13 

3.00

2. 53

2.77

0.88 

1.34

1.74 

2.22

1.98

Au$ 

Days.

9.6 

14.3 

16. 5 

15.0

20. 2 

8.5 

16.8 

13.0 

20. 5 

28.5 

13.4 

17.7 

10.0 

17.3

23. 5

13.6 

11.0

15. 2 

14.6 

13 

13 

16.0

14.0

fust.

Mean

total.

6.71 

3.07 

4.90 

7.53

9.39 

1.51 

5. 84 

14.13 

19.13 

12.38 

8.31 

4.71 

2.37 

4.64

3.51

3.74 

5. 02

3. 39 

5. 67 

8.10

4.62 

2.09

4.49

16.7

U

O

14.0

11.5 

10.0

16 

13 

9

3.27

3.39

1.02 

0.97

2.90

1.99 

2.72

1

16.0 2.16

h 13 

18. 0

19.0

12.0

A 2. 75

7.S6

1.08

(> For 1900 only. c For 26 days only. e May 1 to 24. 1883. /July 8 to 31, 18R2, * August, 1883.
164 GEOGRAPHY AND GEOLOGY OF ALASKA.

Mean precipitation, including melted snow, and the mean number of days with

No.

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14

15 

16 

17

18

19 

20 

21 

22 

23

24

25 

26 

27

28

29 

30

31 

32 

33

34 

35 

30 

37 

38 

39 

40 

41 

42 

43 

44 

45 

46

47

Stations.

Parifir coast.

Sitka .................................................

Kodiak ( 1 )...........................................

Kodiak (2) (Woody Island) .........................

Alaska Peninsula.

Aleutian and Commander islands. 

Unalaska ............................................

Berinfj tica coast.

St. Michael .........................................

Bering Sea. island*.

Arctic coast.

Interior stations.

Holy Cross (mission) .................................

Kolmakof . .:.........................................

Copper River Plateau. 

September.

Days.

17.2 

19.3 

18.4 

20. 5 

13. 5 

19.5 

19.0

22.5 

11.7 

14.2 

12.0 

10.0

24.0

15.9

Mean 

total.

17.66

6.63 

7.79 

12.19

11.39

3.47 

9.67 

22.96 

20.81 

14. 22 

2. 4f, 

4.86 

1.95 

5. 98

5.52

4 58

13.0 7.51

23. 2 9. 85

7.0 

15 

13. 5

18.5

18. 5

11.5

19.5

13.0 

10.5

5.0 

16

9.8

14.0

11 

16.3

18.0 

17.7

7

4.31 

4.06 

2.50

4.98

4.02

«.91

1.48 

0.61

0.80? 

2.41 

1.07

1.48

2.04

3.07 

3.70

0.73

October.

Days.

20.0 

13.2 

22. S 

19.8 

20.0 

12.0 

21.7 

22.0 

20.2 

22. 0 

10.0 

12.2 

18.0 

21.0

23.0

16.4 

n 15. 0

20. 4 

21.2 

19 

15

17.7

11.0

11.4

fi.fi

22.0

7.0 

7.0

3.5 

6

7.8

Mean 

total.

14.11 

7.36 

7.92 

10. 05 

11.47 

3.22 

11.96 

21.50 

21.98 

14.25 

2.06 

4.15 

6.31 

8.95

2.70

5. 33 

a 10. 26

11.58 

10. 32 

7.67 

8.91 

2.60

1.99

1.70 

0. 23

6.06

0. 25 

0. 75

0.37 

0.80

lfi.0 

17 

8 

12.6 

13.3 

22.0 

15.0

8

2.40

1. 57 

1.36 

1.19

S.67

1.58

2.02

November. December.

Days.

27.0 

17.8 

16.9 

18.4 

15.0 

8.0 

19. 5 

13.0 

12.7 

11.5 

7.4 

6.5 

18.0 

9.5

15.5

14.4 

17.0

23.4 

18.0 

22 

20 

16. 5

11.5

4 

11.4 

3?

10.8

22.7

........

2.5 

6.3

8.0 

13 

7.0

8

12. 5 

2 

6 

13.3 

9.8 

15. 0 

13.0

4

Mean 

total.

15.46 

11.27

5. 16 

10.47 

7.51 

2.17 

9.80 

10.51 

9.21 

6. (13 

1.13 

0.88 

6.52 

3. 55

1.42

5.51

7.92

10.95 

11.58 

6.28 

6.46 

2.96

2.84

1.15 

0.45

5.39

0. 75 

0.39

0.73 

0.72 

0.57

0.1,1

2. 33 

0.14 

1.20 

1.43

3.10

2.82

1.50

Days.

19.0 

22. 5 

17.6 

19.8 

17.0 

11.7 

18.9 

19.0 

18. 5 

13.0 

6.0 

7.2 

18.0 

15.0

16.5

13.8

8.5

24.6 

17.2 

17 

22 

17.0

a.o

0.9 

3?

12.0

21.5

3.5 

4.3

5.0

14

10.0 

14 

8

11.0 

11.5 

9.3

2

Mean 

total.

13. 33 

10.41

4.81 

8.16 

8.37 

S. 78 

7.88 

16.81 

1L.05 

5. 95 

0.88 

1.31 

5. 72 

7.91

1.61

4.31 

1. 45

13.99

7.77 

2. 55 

6. 52 

1.62

1.36

0. 75 

0.18

3.38

1.63

0.26

0.43 

0.33 

0. 4,->

1.17

0.82 

1.3B 

1.42

1.07 

1.80

0.20

a October 1 to 27,1882.
PBECIPITATION. 165

0.01 inc:1i or more precipitation, for each month and the year Continued.

Pacific coast.

1 Fort Tongass................

2 Fort Wrangeil..............

3 Killisnoo ..

4 Jnneau (1 j .

HIS.

Year.

Days. Mean

total.

Length of record.

Years.

Limiting dates.

Months.

213.8

199.9

1X5. 4 

201.8

Juneau (2) (wharf)............ I 195.4

Skagivay ...................... 92. (>

7 Sitka

Nuehek (Fort Oonstantine) ...I 203.,> 

Oroa .......................... .'!> 17.S. 0

Fort Liscuin................... 175. 0

Kcnili .........................j 92.4

Tyonok- -.......--...-..--.....j 95. 8

Kodiak (1) .................... 1 161

Kodiak (2) (Woody Island)... 160.4

Maska Peninsula.

L'gasluk....................... | 207.5

Mine Harbor (Herendeen Bay) .......

Coal Harbor (Unga Island) ... 161. 6 

Morzhovoi..................... 1 Of>

133.10

70.88

81.27

21.75

''129.31

81.33 

1(1. 55

23. 44

>45. 00 

58. 94

24. 41

-18. 78'

Aleutian and Commander

islands. \ Unalaska..................... 250.8

Atka Island ................... I 196. 2

143 >60.30

170.1 21.19

Kiska Island ..............

Attu Island..--..--........

Bering Island.............

lleriny Sat coast.

Fort Alexander ............... | 154. 6 33. 09

Carmel Mission (Nushagak) '...._...

Bethel Mission ................ I......

St. Michael.................... 126.8

111.08

81.67

Omalik (mine) ................i........

Bering >S"m islands. 

Gambell (St. Lawrence Island) 116.4

St. Paul Island ................

Arctic coast.

31 Kikiktak (Friends' Mission) ..

32 Point Hope (mission at Tikira)

33 Utkiavi (Cape Stnyth)......... I

Interior stations.

207.0

64.0 

87. H

18.11

40.68

Fort Reliance ......................... ,.--5.08

('amp Davidson ............... j........ i >13.43

Eagle (Fort Egbert) ........... 97.7 11.35

37 I Circle.

Camp Colonna ............

Rampart ..................

Tanana (1) (Fort Adams) .

Tanana (2) (Fort Gibbon)..... 

Xulato (St. Peter Mission) .... 

Anvik .........................

Holy Cross (mission) ..........

Ikogmnt. ......................

Kolmakof .....................

Copper River Plateau. 

Copper Center.................

21.04 

>16.24 

>21.13

13

2

Feb.,

1884; 

,1895;

1902; 

1902;

, 1901;

4 i June, 1868, to Sept., 1870. 

40 | June to Aug., 1868; Apr., 1869, to Sept., 1870; 

1875, to May, 1877; Sept., 1881, to Aug., 1882. 

11 I Jan.. 1889, to Dec.. 1902.

35 i June, 1881. to Mar., 1882: May, 1883, to Oct.,

' Dec., 1889, to Jan., 1892; Dec. 1894 to Jan.

July to Sept.. 1895; Sept., 1896, to Feb., 1897

1 Dec ,"1898, to Dee., 1902. 

30 | Nov.. 1898. to July. 1X99; Sept., 1899, to Aug.

Oct. 1901; May to Dec. 1902. 

.12 i Sept., 18t>7, to May, 1877: Apr., 1881, to Sept.

1 July, 1898, to Dec., 1902. 

16 I May, 1883, to Aug., 1884. 

18 I Oct., 1899, to Mar., 1901; July, 1901, to Mar.

Oct. to Dec., 1902. 

0 I Jan., 1901. to Dee., 1902.

26 ' Sept., 1882, to May. 1886; May. 1899, to Dec. 

June 1884 and Sept., 1899, missing.

2 Nov., 1898, to Dec., 1902. 

13 I Nov., 1898 to Nov., 1899.

17 Jan. 5, 1900, to Aug., 1900; Nov., 1900, to Mar. 

1 May, 1901, to Aug., 1902.

0 I Jan., 1884, to Dee., 1885.

' "o Jan., 1894, to Dec., 1902. 

17 Nov.. 1881, to Apr., 1882; July 8,1882, to May 24, 1883.

10 July, 1881, to Apr., 1886.

14 ! June, 1879. to Aug., 1879; Oct., 1881, to Apr., 1885:

May to Aug., 1886. 

1HI May is, 1885, to Apr., 1886. 

9 Aug., 1880, to Apr., 1881. 

23 ! June, 1882, to Apr.. 188(1.

23 ' Aug., 1881, to June, 1883: July, 1884, to May, 1886. 

6 Jan., and Mar. to July, 1902. 

4 Nov., 1885, to Feb., 1886. 

(i i Aug., 1877, to Dec.. 1878: July, 1880, to June, 1882;

Sept., 1882, to June, 1886. 

9^ Feb. to May, and Oct. 18 to Dec. 1884; Jan. to Mar.,

1885.

32 ' Oct., 1894, to Sept.. 1897; Nov.. 1898. to June, 1899; 

Oct., 1901, to Sept., 1902; days with rain are recorded.

29 , Oct.,1869, toJune,1870: Oct., 1878. to May.1879; June, 

1881, to May. 1883.

"\-2 Aug., 1894, to July, 1896. 

21 ! Nov., 1881. to July. 1883: Sept., 1901, to Aug.. 1902.

16 : Sept., 1SS2, to Apr. 1883: Oct., 1885, to May, 1886. 

18 I May, 1890. to May, 1891.

52 i Get", 1882, to Apr., 1883: Sept., 1884, to Apr., 1885; 

Sept. 1885, to Apr.. 1886; Sept., 1899, to Dec., 1900; 

Nov. and Dee., 1901; Feb. to Dec., 1902. 

June. 1897; June, 1898; July, 1897; July, 1900; Aug.,

1900. 

Nov., 1889, to June, 1890.

Aug., 1882, to Apr. 1883; Sept., 1883, to Mar., 1884; 

1 Sept., 1885, to May, 1886. 

3 Oct., to Dee. 1902.

10 Oct., 1894, to May, 1895; and Jan. 3 to Mar., 1896. 

26 Sept., 1882, to May, 1885; June, July, and Aug., missing, except Aug., 1883.

11 | Get , 1893. to June, 1894; Sept., 1894, to Sept.. 1896; 

1 June, 1897, to May, 1899; Aug., 1899, to Aug., 1901. 

Sept., 1883, to May' 1884; Sept. to Oct., 1884; Jan. to

May, 1885: Oct..'1885, to May, 1886. 

24 Aug., 1883. to July, 1884; Sept., 1885, to Apr., 1S86. 

(Very incomplete.)

1902.

b For 1900 only.
166 GEOGBAPHY AND GEOLOGY OF ALASKA.

Maximum precipitation, in

No.

1

 >.

3

5

11

V?

13

14

15

Ifi

17

1 R

19

 >.!

?fi

27

 >8

 «

30

ai

<>9

35

Of,

37

38

41 1

41

4?

4i

44

4o

4;

Station. 

Pacific coast.

Orc'i

Kodiak (1) .....................................

AZasfca Peninsula. 

Uffashik

JicwfidH a«d Commander islamls.

Bf'i'inu Sea roasL

Bering Sea tslands.

ArcUe coatt.

Interior station*.

Circle. ..........................................

Copper Kmr Plateau.

Jannary.

8. 58

1.50

2.55

3.17

3.84

1.85

1 00

0.37

1.42

1.75

S.58

1.14

0.19

0.11

1.00

0.88

0.28

0.66

February.

3. JO

2.44

0.52

5. 00

4.59

0.70

0.77

1 411

0.2*

1 64

1.05

0.27

0.75

0.04

0 19

0.47

0.93

0.84

0.45

0.13

1.03

March. 

1 . 50

1.10

1 93

1.60

3.14

3.07

5. 24

2. 54

1.29

1 50

1.45

0.8G

0.39

0.08

0. 55

0.43

0.17

0.18

0 98

0 54

O.SS

April.

1.30

Q tyf,

1.30

0.75

1.00

5.00

1.20

0.81

0.74

0.21

0.75

0.17

0.11

0.28

0.50

May.

1.7,1

0, 45

4.00

1.59

1.01

0.63

1.88

1.50

)> 0. Jfi

< !.«>

1.65?

0.66

0.85

0.35

0 86

0 64

0.14

0.24

0 'J9

0. 55

O.M

>0.67.'

0.04

June. July.

1.20 2.50

>1.75? I 1.87

1.10 2.00

0. 35 0. 92

.......... 'U.10

o IQ 2 49

0.80 -2.00

0.47 1.55

0.82 ' 0.98

0.42 0.47

0.16 ...........

0.25? ..........

1.60; 0.71

i

a Foi 1900 only. i> For 26 days only. c For May 1 to 24, 1883. << For July 8 to 31, 1882. e For 29 days, July, 1876.
PRECIPITATION. 167

inches, in twenty-four linurx.

Vo.

1 

2 

3 

4 

5 

6 

7 

8 

i) 

10 

11 

12 

13 

14

15 

16 

17

18

19 

20 

21 

22 

23

24 

25 

26 

27 

28

29 

30

81 

32 

33

34 

35 

36 

37 

38 

39 

40 

41 

42 

43 

44 

45 

46

47

Station. August. SeP£mPacific const.

Fort Wrangell. .................................' 1. OS

Skagway ....................................... 0. 53

Orca. .......................... .... ......... 8.42

Fort Liseum ........ 1 . 60

Kenai ................. . . .... ... 1 . 20

Tvonok..... . .... .... . ... .... ... 2.00

Kodiak (2) (Woody Island) ........ .........' 1.00

Alaska Peninsula. 

Ugashik...... .......... .... .. ......... 1.11

Morzhovoi ......... 1.60

Aleutian and Commander inland*.

Atkalsland ........ ..... . .... ... 1.95

Kiskalsland .............. ......... 1.58

Bering Sea coaxt.

3.10 

2. 00 

1.90 

2.37 

4.00 

0.90 

3.79 

8. 35 

6.70 

2. OX 

0. 61 

1.10 

0.48 

1. 05

1.20

1.90 

2.07

2. 65 

2.16 

1.15 

1.36 

0.91

1. 16

1.95

Bering Sea islands.

Arctic coast.

Interior station*.

Kagle (Fort Egbert) ............................ 0. 7;.

Circle .......................................... 0.80 ...

0.73 

0.29

0.85? 

1.05

0.47

1.13

Ikogmut ........................................' >0. 70?

Copper liner Plateau.

0.71 

1.20 

>1.2fl? 

1.10

0. 27

October. ^ -

5. 15

3.12 

2.1!) 

2.00 

2.30 

1.00 

6.55 

4.37 

7.41 

2.05 

1.77 

1.90 

1.SS 

1.35

0.55

2.05 

/ 1. 75

5. 38 

2.30 

2.00 

1.98 

1.18

0.79

1.85

l.f.2

0.14 

0.53

0.17 

0-08 

0.47

..........

S.05

0.23 

0.61

0.28 

1. 40? 

0.98 

0.59

0. 45

2.15 

3.15 

2.20 

>3. 10? 

2.97 

0.63 

5. 05 

3. 50 

3.02 

8.80 

0.83 

0.88 

1.35 

0. 80

0. 33

2.07 

2.00

4.73 

3.20 

1.30 

1.08 

1.17

1.28

0.9ft 

0.22

0. fif>

1.83

0. 20

0. 30? 

0- 1C 

0. 35

0.14

1.98 

0.10 

0.31 

0.42 

0.71 

0.75 

k 1. 10

1.20

December.

1.70 

2.11 

1.60 

2.01 

2.41 

1.72 

2.82 

3.15 

3.25 

1.66 

0.93 

1.40 

0.81 

1. 25

0.40

1 . 35

0.1,0

ft. 56 

2.95 

0.85 

0.72 

0.65

0. fili

1.14 

0.12

1.61

1.75

0.21

0. 30? 

0.10

ft. as

0.28

1.06 

0.34 

0.42 

0. 27? 

1.08? 

0.42 

3.03

0.10

Length of record.

Years.

2 

0 

13 

2 

4 

0 

17 

0 

1 

2 

5 

4 

0 

0

2

9 

0

4 

3 

0

0 

2

2 

0 

0 

7 

0

2 

1

]

I

0 

0 

0 

0 

0

0

o

0 

0 

6 

0 

0

0

Months.

4 

40 

11 

35 

1 

30 

42 

16 

18 

0 

25 

2 

13 

17

0

0 

17

10 

14

111 

9 

23

23 

6 

4 

6 

9J

32 

29

12

21

If. 

13

52 

ft

8

26 

3 

10 

2fi 

11 

22 

24

5

/ For October 1 to 27. 1882. o For 1883 only. * From November, 1882. < For 1902 only.
168 GEOGRAPHY AND GEOLOGY OF ALASKA.

Maximum, minimum, and mean number of rainy days (i.

19

20

21

22

23

21

25

26

27

28

29

30

31

32

33

34

35

36

37

40

41

42

43

44

45

46

47

Stations.

Pacific ('vatf.

Juneau (2) (wharf) ....

Sitka ...................

Kodiak (1 )..............

Alaska Peninsula.

Aleutian and Commander 

ixlimds.

Kiska Island ...........

Bering Sea coast.

Bering Kea islands.

Arctic coast.

Utklavi (Oapegmy th ) . . . 

Interior KtatlonK.

Eagle (Fort Egbert) .... 

Circle...................

Nulato .................

Am-ik..................

Holy Cross (mission)...

Copper River Plateau.

January.

Max. Min. Mean

22 

21

25

;!0 

 23

8 

24

16

9 

9

......

20

28 

27 

......

20 

23

13

12 

25

6 

9

8

14

6 

22 

14 

17 

18

15

Hi 

9 

9 

16 

7 

(i

Hi

0 

(i

......

9

26 

19

12 

5

'>

4 

19

2 

0

2

3

5

0 

8 

1 

9 

2

......

18. 5 

17.6 

18.0 

18.1 

20.0 

7.5

it;. 8

16 

17. 5

5.3

7.7

14.5 

13.0

26.8 

21.5

24

15.7

14.2

8

8.1

8.0 

21.0

2.0

ft. 7

5. 5 

16

6.2

11. 0

5.0 

15.6

8.0 

13.0 

10.3

February. March. April.

Max.

20 

25

14 

17 

3 

26

1!

9 

9

(-19

26 

20

19 

12

12

15 

19

2 

12

10

9

11

8 

9 

11 

9 

11

Min.

17 

13 

7 

6 

8 

2 

7

4

1

1!

< (>

15 

11

0

0

3 

12

1

2

3

0

5

fi 

3

3

Mean

21.5 

20.0 

14.9 

11.2 

11.7 

tl.li 

15.9

8.3 

5.0

k. I 

5.7 

14

Max.

18 

17 

27 

24 

18 

4 

29

22

14

e

7 0

'li). 0 20

f ^

21.0 

15. 5

7

13.0

7.5

5.5

0

8.6 

15. 0

1.5 

5.3

6.5 

14

5.8

Hi

8.6

7.0 

6.0 

6.6 

7. S 

6.0

25 

19

15

18

14

18 

16

3 

12

7

8

......

13

16 

20 

14 

17 

20

Min.

17 

7 

7 

15 

10 

2 

9

1

3 

2

......

q

18 

7

10 

10

1

7 

12

3 

1

2

2

......

6

9 

13 

5 

13

8

Mean Max.

17.5 

1'i. 6 

15.0 

18.7 

14.2 

3.0 

18.0 

21

11.0 

145

7. 1 

4. 5

14.0

22.2 

12. 0 

9

12.5 

14.5

7.4 

3.5

11.0 

16.5

li. 0 

6.6

4.5

i.8

12

13.0

12.5

15.3 

10.6 

14.7 

14.0

23 

21 

21 

17 

23 

8 

24

11 

6

Min.

15 

13 

3 

11 

13 

13 

10

Mean

19.0 

16.6 

11.0 

15.0 

17.0 

10.5 

16.2 

IS 

It M

4 6.4 

2 4.0 

14

20

27 

27

18 

16

16

23 

21

11 

4

13

6

>3 

15 

13 

16

17

(i

19 

1]

Max.

16 

25 

19 

25 

18 

7 

20 

22

9

10.5 ......

14 0 -----

13.2

24.8 

15. 2 

11

16

7 

5

1

4

7

1 

0

1

6

1

2 

4

3

5 

4

11.5 

10.5

7.8 

4

10.8 

15.5

5.0 

0.6

z.r,

8.6

S. S

>f 

7.6 

7.4 

11.0 

9.3

19

24 

22

13

18

14

12 

26

7 

15

6

7

May.

Min. Mean

15 

12 

li 

11 

12

;

15

1

6

11 

12

10 

11

5

2 

10

0 

0

6

6

12 12

...... ....

8 

11 

14

6 

2

8

15. 5 

IS. li 

12.3 

1(1.7 

15. 5 

4.7 

10.1 

18.5 

('20 

9.0 

<i.4 

S.7 

14 

15.0

17.0

11.8 

t/8.0

17.2 

15.8 

ff!

8.5

14.2 

10

9.1

2

6.8 

21 . 3

3.5 

6.6

6.0 

7 

0.3

k

12.0

4.0 

7 

5.1 

9.0
RAINY DAYS. 169

number of days with mm or melted mowfall^O.Ol inch).

Xo.

 - 

1

10

11

12 

13

14

15 

111 

IT

18

19 

20 

21 

22

23

21 

25

26 

27

28

29

30

SI

32 

33

31

35 

36 

37 

38 

39 

40 

41 

42 

43 

44 

45 

46

47

Stations.

J'ac/flc coast. 

Fort Tongass

Fort Wrangoll..........

Junean(l) .............

J minm (2) (wharf).... 

Skaffwnv

Sitka...................

Orca

Max.

15

18

;«

n

20 

12

June. ~^.

7 

« 

3 

11

9 

1 

6 

9

Fort Ijiscum.... ....I

Kenai ..................

Tyonok.................

Kodiak ( 1 )

Wood v Island......

Alaska Peninsula. 

Tgashik

n i

7 0

Me7i,

10.3 

13.7 

.9.9 

11.6 

12.7 

5.0 

J.I. li 

10. 5 

Ml 

8.0 

5.1 

4.2 

9

S. 7

. ..' .. 11.5

Mine Harbor ........... .......

Coal Harbor............

MorzllOYOi..............

Aleutian and Comma-ndcr 

Mands.

rualaska...............

Atka Island

Kiska Island .:......... ...... ...... 

21 , 3 111. /,

13 8 li.-i 

18 , 10 13.6

At tn Island. ............

"Rui-ino- Tal ii^i-l

Fort Alexander.........

Civrmel Mission

20 

14

5 

12

12. 5

13.0 

9

Bethel Mission . ... . . .

St Michael

Oinalik (mine).........

Gambell

St. Paullslana.........

Arctic, court. 

Kikiktak

Point Hope.............

Utkiavi (CapeSmyth).. 

Interior stations. 

Fort Reliance..........

Kagle (Fort Egbert).... 

Circle...................

C "iimp Colon 11:1

Rampart ...............

Fort Adams ............

Fort Gibbon. ...........

Nulato...... ............

Anvik..................

Holy Cross (mission)... 

Ikogmut................

Kolmakof .............

Copper Rirer Plateau. 

Copper Center

19

13 

12

4

10

5

2 

3

3 

7

............

13 (i

12 6

10.4

II. 0

3.5 

9.0

11

9. 5 

4

5

Max,

22 

20 

21 

19 

13 

10 

23

13

July. 

Mill.

13 

8 

4 

13

7 

3

14 

9

12 ' 5 

9 5

............

in 6

18 10 

20 4

.... ..I.... ..

20 

21

22

13 

15

11 

12

13

..... .....

8.7

......

18

:

12 

12

5

5 

11

13

M^i

16.6 

15. 8 

11.7 

15. 5 

11.0 

5.7 

14.9 

18.5 

11.0 

14 5

J

MaTx.

-

18 

20 

28 

20 

25 

17

16

22

8.9 19

8.2 20

7 ......

11.8 ......

25.5

10. (i ! 21 

(-5.0 ......

14.8 

12

15.7

10.7 

14

13.6

S.O 

10.0

8.0 

11.6

18 

17

19 

15

25

20 

15

18 

15

14 |...... 

13.01 16

8.5 |......

......1......

" 1

1

1

 !'"

:::::.i::::::

!

16

29

ugust. 

Mill. iM I'll n

4 u.f, 

10 14. 3 

1 16.5 

8 15. (i 

16 20.2 

" 0 8. 5 

8 16. 8 

10 13.0 

19 20. 5 

..... 28. 5

8 

17

8

12 

12

11 

13

IS. 4 

17.7

10

17 3

28. f>

13.0 

11.0

1.-..2 

14.6

in

13

16.0

14.0

10 

......

r.

12

5 

5

10

16.7

11.3 

14.0

11.5 

10.0

r

16

......

16

Septenib 

Max., inn.

23 9 

24 '' 14 

26 ! 14 

26 13 

25' 16 

17 10 

26 13

19 

. ...

16

U

5 

11

.::...:..:..

.:..........

23

27 

23

21

22

13 

21

15 

15

14

12

.........

ol3 

18.8

>8.5?

1!)

12

19 

20 

23

22

11

19 

16

10 

15

9

10

18

11

5

7

8

4 

11 

7? 

12

19.3 

17.2 

19.3 

18.4 

20.5 

13.5 

19.5 

19

16.5

'». r,

11.7 

14.2 

12

r

Max.

22 

17 

28 

27 

20 

16 

28

14

14 

IS

10 ......

'.'A 0

15.9 

13 0

23.2 

19.0 

7

15

13.5 

18.5

1S.5

11.5 

19.5

13.0

10.5

5.0

9.8

14.0

11.0 

16.3 

18.0 

17.7

7

20

30 

23

ctobe 

Min.

18 

10 

16 

8 

15 

9 

1">

25

3

7

11

23 

20

............

28

17

23

9 

29

9 

12

5

10

12 

4

6

3

17

5

2V

2

6

r. 

Mean

20.0 

13.2 

22.8

10.8

20.0 

12.0 

21.7 

22 

20.2 

22.0 

10.0 

12.2 

IS 

21

23.0

18.4

'15.0

26.4 

21. 2 

19 

15 

17.7

11.0 

......

11.4

6.fi 

22.0

7.0 

7.0

3.5 

6

7.8 

......

20 6

24 

19 

30

27

0

3?

2

18. 0

17 

8 

12. 6 

13.3 

22.0 

15.0

8
170 GEOGRAPHY AND GEOLOGY OF ALASKA.

Maximum, minimum, and mean number of rainy days (»'. e., number of days with rain or melted

snov;fall^>0.01 well).

No.

i6

I

6 

7 

8 

9 

10 

11 

12 

13 

14

15 

16 

17

18

19 

20 

21 

22 

23

24 

25 

 26 

27

28

29 

30

31 

32 

33

34 

35 

36 

37 

38 

39 

40 

41 

42 

43 

44 

45 

46

47

November.

Stations.

Max. Min.

Partjtc coast.

Fort Wrangell........ ....................... 24 13

Kenai........ . . . ..... 13 4

Alaska Peninsula.

Aleutian and Commander islands.

Bering Sea coast.

St. Michael .................................. 19; 3

Bering Siea islands.

Arctic coast.

Utkiavi (Cape Smvth). ..................... 11 2?

'Interior stations.

Copper Hirer Plateau.

Mean.

27.0

17.8 

16.9 

18.4 

15.0 

8.0 

19.5 

13 

12.7 

11.5

7.4 

6.5 

18 

9.5

14.4 

17.0

23.4 

18.0 

22 

20 

16.5

11.5

4 

11.4 

3V

10.8 

2-2. 7

2.5 

6.3

8.0 

13 

7.0

8

12.5 

2 

6 

13.3 

9.8 

15 

13

4

December.

Max. Min.

23 15 

27 ; 17 

23 10 

24 18 

24 8 

20 ' 6 

28 9

15 12

12 4 

8 3

22 6

26 23 

21 10

25 8 

14 5

15 ; 2

15 9 

26 19

5 ' 2 

7 2

8 2

8 4

12 2

16 5 

13 10 

12 7

Mean.

19.0 

2-2.5

17.6 

19.8

17.6 

11.7 

18.9 

19 

13.5 

13.0 

6.0 

7.2 

18 

15

16.5

13.8 

8.5

24.6 

17.2 

17 

22 

17.0

9.0

6.9 

3?

12.0

21.5

3.5 

4.3

5.0

7 

5. 7

14

10.0 

14

8

11.0 

11.5 

9.3

2

Means.

213.8 

199.9 

185. 4 

201.8 

195. 4 

92.6 

207.9 

203.5 

6175.0 

175.0 

92.4 

95.8 

<-161.0 

160. 4

il 207. 5

/161.6 

106. 0?

fc250.8 

196.2 

*>14:{ 

m>162 

H 170.1

154.6

126.8

116.4 

207.0

64.0 

87.5

........

97.7

>116

>101.4 

127.4 

>130 

->II3. 6

Length of 

record.

Years. Months

 2 4 

0 . 40 

13 11 

2 ! 35 

4 . 1 

0 30 

17 42 

0 16 

1 , IS 

2 0 

5 , 26 

4 2 

0 13 

0 17

2 0

9 0 

0 17

4 , 10 

3 14

o m

0 9 

2 23

2 23

0 ' 6 

0 4 

7 6 

0 ' 94

2 32 

1 29

1 12

1 ," 21

0 | 16 

0 13 

0 52 

0 5 

0 8

0 26 

0 3 

0 10 

0 26 

6 11 

0 22 

0 24

0 5

a A trace fell on 4 days. 

i> For 1900 only. 

«Nov., 1898, to Nov., 1899. 

dJan., 1884, to Dec., 1886. 

« For 8 years.

/Jan., 1894, to Dec., 1902. 

a May 1 to 24, 1883. 

'(July 8 to 31 1882. 

*Oct. 1 to 27, 1882. 

fcJuly, 1881, to Apr., 1886.

(May, 1885, to Apr., 1886 

m Aug., 1880, to Apr., 1881. 

"June, 1882, to Apr., 1886. 

o For 1883 only.
FROSTS.

Last and first frost* at Alaska stations.

171

Station and year.

Pacific coast province. 

Metlakatla : 

1891 .....................................

1892 ......................................

1893 ......................................

Fort Tongass: 

1868 .....................................

1869

Last killing 

frost.

Apr. 6

1870.....................................

Fort Wrangell: 

1869 .....................................

1875 .....................................

1876 ..................... . .........

1882 .....................................

Juneau: 

1889 .....................................

1890.....................................

1891 .....................................

1895 .....................................

1899 .....................................

1900.....................................

Chilkoot (Portage Bay): 

1881 .....................................

1882.....................................

Skagway: 

1899 .....................................

1900 .....................................

1902 .....................................

Howkan: 

1882 .....................................

Killisnoo:

1884 .....................................

1885

Mar. 14 

Apr. 30

Last frost. ' First frost.

.......... Sept.

Apr. 15 Oct. 

May 1 Oct.

.......... Nov.

Mar. 19 Sept. 

Mar. 14 ......

.......... Sept.

Apr. 20 Oct. 

June 5 Sept. 

Oct

Xnv

Mar. 29 Oct. 

May 2 Sept.

fip.nt.

QAT^

Oct

.......... .......... Sept.

...... Mav 9

Apr. 9

July 7 Aug.

Sp.nt

...---... J.. ........ Sept.

Spnr

1888 ..................................... ' - - - . rvr

1891

1892 .....................................!..........

1893. ............................... ...........

1895 .....................................

1897 .....................................

Sitka: 

1868............----.----.......---......

1869 .....................................

May 6 Sept. 

Mar. 31 Oct. 

Mav 2 Oct.

ftpnt

.......... Sept.

Apr. 21 ......

.......... Sent.

First killing 

frost.

30

14 

19

6 

29

20 

5 

14 

2

18

6 

20 

10

4

11 

6

27 

26 ..........

Nov. 17 

Oct. 30

Dec. 19 

Dec. 17

Oct. 15 

Oct. 29 

Oct. 29 

Oct. 8

Sept. 19

Growing 

days.

225 

207

210

229

182

191? 

141?

Sept. 22 ' ........

Sept. 4 117?

13 .

28 

15 

27 

14 

18 

3

Oct. 12?

Sprit 1 9.

50?

>143

>197 

>169

27 ........... ........

19 ..........

17211 No. 45 06 12
172 GEOGBAPHY AND GEOLOGY OF ALASKA.

Last and first frosts at Alaska stations Continued.

Station and year.

Pacific coast province Continued.

Sitka Continued. 

1870 .....................................

1871.....................................

1872....................................

1873.....................................

1881.....................................

1900 .....................................

1901 .....................................

Fort Liscum : 

1901. .......................................

Nuchek (Port Etches) : 

1883.....................................

Kenai : 

3883.. ...................................

1884........------....---------..........

1899 .....................................

1900.....................................

1901 .....................................

1902.....................................

Kodiak: 

1899 .....................................

Woody Island (Kodiak): 

1901.....................................

Alaska Peninsula.

Coal Harbor (Unga Island): 

1893.....................................

1894.....................................

1895 .....................................

1896 .....................................

1897................................... ..

1898.....................................

1899 .....................................

1900.........-.........................'..

1901 .....................................

1902.....................................

Morzhovoi: 

1881 .....................................

Ugaghik: 

1884..................... ................

1885.....................................

Last killing 

frost.

May 27

May 12

May 16

May 31

May 8

May 29

Apr. 25

Last frost.

May 8

June 12

PFirst frost.

Oct 19

Nov. 5

Aug. 25

Oct. 5

Sept. 14

Sept. 24

Aug. 18

Sept. 1

Sept. 6

Sept. 2

Sept. 15

Sept. 17"

Sept. 18

Sept. 8

Sept. 10

Sept. 22

Oct. 29

First killing 

i'rost.

Oct. 31

Oct. 7

Oct. ]

Nov. 1

Sept. 29

Aug. 25

Aug. 24

Nov. 24?

Sept. 15

Oct. 6

Oct. 13

Sept. 10

Oct. 24

Sept. 17

Sept. 15

Nov. 3

Aue. 19

Growing 

days.

>162

122

77?

86?

>128

150

102

>123

109

202
FROSTS. - . .. 

Last and first frosts at-Alaska stations Continued.

178

_ _ _

. Station and year.

Aleutian Islands. 

Unalaska:

- 1879 ..............................

1881 .......:..................:...:.;:."...

Attu Island: 

1880... ..........................

1881 .............................

Bering Sea coast province. 

St. Michael:

1877.............;.-.......-........-.-..

1878.....................................

." 1880.....................................

1881 .....................................

1900 ..................

Carmel Mission: 

1902. L. ...............................

Gambell (St. Lawrence Island) : 

"l895 -....--.-...'.---. .....---..-....---..:.

1902........ .........................

Arctic Ocean const. 

Point Hope:

1894 ..................................

1895 ...... .....J...... ...................

. Interior province. 

Fort Reliance:

" 1885 ...............................

Gamp Colonna:

. : 1889................. ..................

1890...................... ..............

Camp Davidson: 

1890.................. .................

1891 ...................................

Eagle: 

1882 ...... .:... ............. L..J.....

1884... .................

1885...............................:.....

Circle: , " ' 

1898 ..................... .J.... ......

1899 ..................................

Fort Yukon: 

1899. ..................

1900 . -.... .^.. ........................ "!7.

-Last-killing 

. frost.

'--

May 81?

May 14

June 27 

June 3

May 11?

Last trost.

Feb. 14

May 7

May 28?

Apr. 29

First'frostT"

Oct. 30 

July -21

Sept. 20

Sept. IS 

Sept. 2 

Sept. 18 

Sept. 14

Sept. 21

Aug. 11 

Sept. 29

Sept. 13

Aug. 16

Sept. 1

Aug. 19

Oct. 4

First killing 

frost.

Sept. 30

Sept. 5.

Oct. 16 

Oct. 15

Sept. 27 

'Oct. 17

Aug. 13

Aug. 28 

Sept. i

Nov. 28?

Sept. -1 

Oct. 6

Growing 

days. »

136?

106?

} 171?

I 47?

112?
174 GEOGRAPHY AND GEOLOGY OP ALASKA.

Last and first frosts at Alaskan stations Continued.

Station and year.

Interior province Continued. 

Holy Cross Mission: 

1894 .....................................

1895 ............................... .....

1899 .....................................

1900 .....................................

1901 .....................................

Kolmakof: 

1883 .....................................

1884 .....................................

1885 ...................... ..............

Last killing 

frost.

Apr. 30

May 30

Last frost. First frost.

Oct. 3

Sept. 7

Aug. 3

Aug. 23

Aug. 29

Sept. 20

First killing 

frost.

Oct. 7

Sept. 26

Sept. 19

Aug. 12

Aug. 31

Oct. 12?

Growing 

days.

104

AQ

Dates of opening and closing of certain Alaska streams.

River and station. *fn*g£

Yukon Hirer. 

Fort Reliance:

1882 . ..... ................ .....................

1883 ..............................................

1885..............................................

1886 ..............................................

Eagle: 

1882 ..............................................

1883..............................................

1884 ..............................................

1885...........--.--.-..-.....---......--....-....

1886 ..............................................

1902 ..............................................

Circle: 

1898 ..............................................

Fort Yukon: 

1899 ..............................................

1901 ..............................................

1902..............................................

Fort Gibbon: 

1902..............................................

Month of the Tanana: 

1882 ..............................................

1883 ..............................................

May 6

May 15

May 4

May 8 

May 16

May 13«

May 20 

May 6

Mav 10

River clear.

May 9

May 12 

May 19

May 20

Mav 13

Ice began 

running.

Oct.

Oct.

Oct.

Oct. 

Nov.

Oct.

Oct.

22

17

13

5 

9

21

3

Oct.

Oct. 

Oct.

25

15

25

River closed.

Nov.

Nov.

Nov.

Oct.

2'

9

5

10

Nov.

Oct.

19

26

Nov.

Oct. 

Nov.

6

30

4

ft Yukon River opened 13th. of May. Water enough for sluicing on Deadwood; also on Mastodon, 20th of May.
ICE. ON STREAMS.

Dates of opening and dosing of certain Alaska streams Continued.

175

River and station. *£**£.

Yukon River Continued. 

Mouth of the Tanana Continued. 

1885 ........................................................

1886 ............................................... May 18

Nulato: 

1894 >> ... ...... .... ......... ...........

1895 .............................................. May 22

Anvik: 

1882 ........................................................

1883 .............................................. May 15

1884 .............................................. May 17

1885 .............................................. May 16

Anvik River. 

Anvik:

1882 .............................................. ......

1888 ..................... !... ...................... May 12

1884 ................ ^............................. Mav 14

1885.............................................. Mav 8

Yukon Rirer. j 

Holy Cross Mission:

1893 .............................................. Mav 19

River clear.

May 29

Mav 22

May 26

Mav 22

May 16

Mav 10

Ice began 

running.

Oct. 14

Oct. 26

Oct. 25

Oct. 5

Oct. 24

Sept. 29

River closed.

Nov. 29 «

Oct. 16

Oct. 27

Oct. 12

Oct. 14

Oct. 1

1894

1895

1896 .

1897 . 

L898 .

. May 23 June 1 Oct. 14 ' Oct. 24

. May 22 j May 30 ..........1..........

. May 27 ' May 29? ' Oct. 10 Nov. 3

. May 19 May 21? .......... Oct. 19

., Apr. 30?

1899 ...................

1900 ...................

1901 ...................

Ikogmut (Russian mission):

1885 ...................

1886 ....................

_...._......-...... Oct. 5 Oct. 29

Apr. 29 ! May 20 Oct. 16 j Oct. 25 

June 1 June 3? ........

Mav 26 ! June 6

Kolmakof:

1883 ...

1884 ...

Kuskokwim River.

1885 .

1886 . Mav 11

Oct. 15 Oct. 30

Oct. 24 

Oct. 12?

Apr. 28 ..........; Nov.

May 18

Fort Wrangell: 

1882 ......

Fort Wrangell River.

a Nov. 9, water rising on Yukon.

Oct. 10 

f> Main channel open until Oct. 24.
176 GEOGRAPHY AND GEOLOGY OF ALASKA.

Dates of opening and closing of certain Alaska streams Continued.

River and station.

Kenai River. 

Kenai:

1899 ..............................................

1900 ...............................................

Fish liiver.

Omalik: 

1884 ..............................................

1885 ..............................................

Ice began 

running.

Mar.

May 

May

18

21 

9

River clear.

Mar. 29

Ice began 

running.

Dec. 4

River closed.

Dec. 14

Sept. 25

Dates of opening and cloning of bays and harbors.

Station.

Fort Tongass: 

1868...................

Kenai: 

1883...................

1889...................

1900...................

Coal Harbor (Ungal.): 

1899...................

Carmel: 

1902....... ............

Gambell (St. Lawrence I.): 

1901...................

1902...................

St. Michael: . 

1874...................

1875...................

1876...................

1877...................

1878...................

1879...................

1880...................

1881...................

1882...................

1883...................

1884...................

Bay opened. Bay closed.

Feb. 7

Mar. 29

Mar. 13 

May 8

Apr. 22

May 25 

June 8 

June 13 

June 15 

June 9 

June 27 

June 11 

June 9 

June 8 

June 10

Nov. 6 

Dec. 27 

Dec. 9

Nov. 9

Dec. 3

Nov. 20 

Nov. 6 

Nov. 15 

Nov. 15 

Nov. 9 

Dec. 6 

Dec. 7 

Nov. 25 

Nov. 21 

Oct. 10

Station.

St. Michael Continued. 

1885..................

1886..................

1887..................

1888..................

1889............ ......

1890..................

1891..................

1892............... ...

1893..................

1894..................

1895..................

1896..................

1897..-.-.-.--.. ......

1898...................

1899..................

1900. ............... ..

1901..................

Friends' Mission: « 

1897.. .... ............

1898.. ................

Point Hope: 6 

1894..................

1895..-----...........

1896..................

Bay opened.

June 30 

June 5 

June 14 

June 8 

June 23 

June 5 

June 9 

June 11 

June 10 

June 23 

June 18 

June 25 

June 22 

June 13 

June 10 

June 8 

July 3

June 7

July 17 

Aug. 1

Bay closed.

Nov. 5 

Nov. 13 

Nov. 2 

Nov. 18 

Nov. 16 

Nov. 11 

Nov. 14 

Nov. 7 

Nov. 5 

Nov. 1 

Dec. 7 

Nov. 21 

Oct. 25 

Oct. 31 

Nov. 7 

Nov. 22 

Nov. 2

Oct. 1 

Oct. 20

Nov. 19

«At Kikiktak, Kotzebue Sound. i> Near Tikira. " Usually clear !rom July 1."
CLIMATE. 177

SPECIAL CLIMATOLOGIC TABLES.

OBJECT OF TABLES.

The accompanying special tables relating to Killisnoo, Sitka, and Coal Harbor 

(Unga Island), pages 179-188, are designed to show certain interesting and important 

features of the respective local climates, which can be studied only after a continuous 

record extending over a considerable number of years is available. The immediate 

purpose is to bring out the most frequently recurring values of certain climatic 

elements and facilitate their comparison with the so-called "mean values," which 

are the values usually asked for and presented in climatologic papers.

" SCHEITELWERTE."

The "Scheitelwerte" is denned by Prof. J. Hann as the "Temperature which 

recurs most frequently within a given period of time," « From his discussion of this 

element the following has been extracted:

"Formerly it has been tacitly assumed that these two quantities [Scheitelwerte 

and mean value] are the same, as is true in the case of the arithmetical mean of observations or measurements of a quantity whose magnitude is always constant, but the 

observations are subject to accidental errors. Closer investigation, however, has 

shown that this is not the case with meteorologic data * * * The frequency of 

the various temperature groups must be counted from many years of observations, 

however, before one is able to determine the most frequent group with any degree 

of certainty. * * * The calculation of the frequency of occurrence of definite 

temperature groups forms a valuable extension and specialization of our knowledge 

of the temperature conditions of any locality. The briefest expression of such conditions is given in the means, and the ' Scheitelwerte' can not be substituted for 

them.'"'

MANNER OF CONSTRUCTING TABLES.

A simple table of this class is presented on page 179, which shows the frequency 

of various maximum temperatures in each month at Killisnoo. The table as printed 

consists of a series of 12 columns, one for each month, and a series of horizontal 

lines, to each of which is assigned a given temperature. To construct this table one 

proceeds as follows:

Having determined all the observed maximum temperatures by months and 

years, the number of times each maximum temperature has occurred in any month 

at a station is then entered on the corresponding lines and proper month column 

of the table. Thus, it was found that the maximum temperature in January reached 

42° in six different years, so this fact was recorded by writing the figure 6 on the 

line numbered 42° and in the column headed January. This procedure is repeated 

until the number of times of occurrence of every recorded maximum for each month 

has been entered. The complete table then presents the appearance of the table 

on page 179.

a Haim, J., Lehrbuch der Meteorologie. Wien, 1902. pp. 118-115. 

& Hann, J., op. cit., pp. 113-114.
178 GEOGRAPHY AND GEOLOGY OF ALASKA.

USE OF TABLES.

The usual maximum temperature for any month at Killisnoo during- the 

period covered by the table is shown opposite the largest figure in the column 

for the proper month.

The table shows also at a glance the highest and the lowest maximum 

temperatures for the months and for the year and furnishes a basis for judging how 

frequently these extremes have been reached or even approached. By comparing 

the number of times of occurrence with the number of years of observation one is 

enabled to judge more accurately of the chances of a given maximum temperature 

occurring again. Thus the chances seem to be two to one that the maximum 

temperature at Killisnoo in January would be 4-2° rather than 40°. Again, the table 

shows that in July there is an even chance of the maximum temperature being 

71°, or lying between 73C and 74°; whereas the chances of the maximum lying 

between 71° and 74° far exceed the chances that it will lie between 79° and 80°, 

and the chances of the temperature again reaching the observed extreme maximum 

of 84° is seen to be very small.

Tables of similar construction show the frequency of the various minimum 

temperatures and of the various numbers of rainy days in each month at Killisnoo 

and at Coal Harbor, and the frequency of various numbers of rainy days at Sitka.

DISCUSSION OF THE FREQUENCY TABLES FOR KILLISNOO. 

FREQUENCIES OF MAXIMUM TEMPERATURES.

The table on page 179 shows the following general features: During the period 

covered by the table the highest temperature reached was 84°, in the month of 

July, and this once only. The most frequent yearly maximum is seen to have 

been 71°, characteristic of five years out of the nineteen recorded; but a maximum of either 74° or 75° was reached during seven years out of nineteen. 

Hence it may be inferred that the maximum for any year is more likely to fall 

between 74° and 75° than to hit upon 71°.

Some months show the magnitude of the individual frequencies and the 

magnitude of the sum of several frequencies; the more frequent temperatures 

tend to fall within certain limits, e. g., 46° to 49° in November. Other months 

seem characterized by the low magnitudes of the individual frequencies and also 

by a scattering of them over a greater range, e. g., May. It seems to be a fair 

and logical interpretation of these features to conclude that future temperature 

maxima (or minima) will exhibit much the same characters as those of the past, 

and that one may expect to find the future temperatures coming close to those 

which in the past have been most often attained. In the case of a month like 

May at Killisnoo, on the other hand, the table gives no ground for expecting the 

maximum to fall, with even a moderate degree of certainty, within a group of 

limited range. Taken month by month the table shows that January is most 

likely to have a maximum temperature between 39° and 42° (eleven times), preferably 42° (six times), but that there is an almost equal chance for the maximum
SPECIAL CLIMATOLOGIC TABLES. 179

Table of frequencies of absolute maximum temperatures at KiHisnoo.

[Period covered: May, 1881, to February 23, 1885; June 8,1885, to October 31, 1885; March-December, 1886; January-March, 

September-December, 1888, and January 1, 1889, to December 31, 1902.]

0 J^

S3 ..............

82 ..............

81 ..............

79 ...............

78 ..............

77 ..............

75 ..............

73..............

71 ..............

70 ...............

67 ...............

6B ...............

til ...............

59 ...............

58 ...............

55........ ......

52 ...............

51 ...............

50 ...............

49 .... ..........

46 ...............

44

12...............

41 ...............

39 ...............

00

Yearsobserv'd

1 

Jan.

2

19

Feb.

o

19

Mar.

3

4

19

Apr.

1

o

4

1

o

]

17

May. June.

i

'

1 2

......... 8

.....:.' i

i ' i

1 3

'> >

.

2 ........

1

19 19

July.

3

20

Aug.

4

2

20

Sept.

:

;

21

Oct.

4

1

'2

o

21

Nov.

2

4

5

1

1

20

Dec. Year.

........ 1

g

........ a

1 ........

1 ........

2 ........

2 ........

2 .... ..

3 ........

20 19
180 GEOGBAPHY AND GEOLOGY OF ALASKA.

to lie between 37° and 40C (seven times). In February the maximum has most 

frequently fallen between 41° and 42° (eight times), and almost as frequently (six 

times) between 44° and 45°, while the extreme of 50° has been reached but once. 

During March the maximum temperature has occurred by far the largest number 

of times (thirteen) between 42° and 45C , and has shown very little preference for 

43° (four times), while the highest temperature, 52°, has been reached but once. 

In April the maximum is seen to fall more frequently in the interval between 

45° and 48° (eight times) than in any other similar interval. There seem to be 

two secondary groups, however, with a frequency of three each at 52°-53° and 

55°-56°. The extreme maximum of 63° was reached but once. The table shows 

a very decided rise (12°) in the absolute values of the most frequent maximum 

temperature on passing from April to May. In the latter month these temperatures show only a moderately developed tendency to group themselves together; 

the most frequent single maxima occurred only twice each in nineteen years, and 

these were five in number. The frequency numbers show their strongest grouping 

(ten times) between 60° and 65°, with a slight tendency to subdivide at 60° to 61° 

and 64° to 65° (each four times). The extreme maximum was 76° (once).

From June on the maximum temperatures draw together again into more 

limited and more sharply defined groups. For June they are distinctly grouped 

between 68° and 71° (eight times), but the most frequent single temperature 

within the group, viz, 08° (three times), is matched by an isolated maximum of 

74° and almost equaled by the extreme maximum, 76° (two times).

The highest maximum temperature for the period of the table was 84°, and 

occurred in July (once), but the most frequent maxima for this month lie between 

71° and 74° (eleven times), with a distinct preference for 71° and 72° (seven times 

together).

The extreme maximum of August, 81°, is several degrees lower than that for 

July, as is the grouping of the most frequent maximum. A'iz, 68° to 72° (thirteen 

times). The grouping of the frequencies within the latter limits does not show so 

great a difference from those for July. In August the most frequent single 

maximum was 72° (four times), 1° higher than that for July, while the general 

preference seems to have been for the interval 70° to 72° (nine times), or 1° 

lower than that for July.

The more frequent maximum temperatures now again begin to decrease 

rapidly. In September they are well grouped between 60° and 64° (fifteen times), 

with some preference for 63° (four times), and but one occurrence of an extreme 

maximum of 69° only, and one each of 58° and 59°.

In October the frequencies are not so closely grouped. They come between 

57° and 50° (twenty times), with a concentration between 54° (four times) and 

55° (three times). The extreme maximum was 60° (once).

November was characterized by a slight scattering of the maxima, shown 

by the fact that the grouping between 46° and 49° (twelve times) includes little 

more than one-half the total occurrences for the month. The occurrences outside 

this group usually have frequencies of only 1, and inside the group are distinctly 

concentrated at 47° (five times) and 49° (four times).
SPECIAL CLIMATOLOGIC TABLES. 181

December shows a somewhat greater scattering of the maxima, the total 

range being from 54C (once) to 40° (three times), but does not match January 

in this respect. The table shows, however, that the December maximum has a 

well-developed tendency to fall between 45° arid 40° (sixteen times), with a 

marked concentration of frequencies at 41° (five times) and 40C (three times).

FREQUENCIES OF MINIMUM TEMPERATURES AT KILLISNOO.

The table of frequencies of absolute minimum temperatures at Killisnoo (p. 182), 

was constructed on the same principle as the foregoing one. It has somewhat more 

interest for the farmer since it is the unexpected occurrence of extremely low 

temperatures which most often plays havoc with his crops.

The column headed "Year" shows that in every one of the twenty years of 

record the extreme minimum temperature fell as low as 11°, and in fifteen years fell 

as low as 4° or even lower. The most frequent extreme minimum fell between 4° 

and 2° (eight times) but this proportion of the total number of years, 40 per cent, is 

not a sufficient basis for any very positive expectations. The fact of chief importance is that the extreme minimum temperature is sure to fall as low as 11°.

A study of the individual months is best left to the reader, but a few important 

features may be pointed out. The first feature to attract attention is the marked 

scattering and small magnitude of the frequencies shown by the minimum temperatures in the winter months, contrasting strongly with the marked grouping and 

higher magnitudes shown in the summer months. This indicates that the probable 

extremes of the next winter can not be closely estimated; they have been too uncertain in the past; while the much more important summer minimum can be more 

closely predicted.

The table shows clearly that all of July and August may be counted upon as 

safe growing months, for their minimum temperatures very rarely fall below 40° 

and usually remain closer to 42°. In the spring it is apparent that temperatures 

injurious to growing plants are sure to be met with through April, and that May is 

very subject to freezing temperatures, the minimum of this month usually falling 

between 34° and 29° (fifteen times in nineteen years), and often reaching 32° to 34° 

(nine times).

Passing to the fall months, the grouping of the minima within well-defined 

limits during September and October is at once striking. During September the 

minimum falls most frequently in the group between 37° and 34° (eleven out of 

twenty-one times), but has also shown preference for 31° (six times); while in October 

there are two well-defined groups, viz, 32° to 30° (eight times) and 28° to 25° 

(thirteen times). From these facts it is evident that September is not likely to favor 

crops for more than half its days, and that October is sure to put a stop to the further 

maturing of all crops.
182 GEOGRAPHY AND GEOLOGY OF ALASKA.

Table of frequencies of the absolute minimum temperatures at KilJisnoo.

[Periods: May 1, 1881, to February 28, 1885; June 8, 1885, to October 31, 1885; March to December, 1086; January to March 

and September to December, 1888; and January 1, 1889, to December 31, 1902.]

°F.

47 .............

46

44

41 .-----------.

40

35....-..--.--.

34 ..----.......

00

09

90

27 . .........

25 .----..------

00

12'*

20.-.-...-...-.

19 .............

10

17..-....-.---.

 JO

11 .............

10.............

Q

s .............

1

3.............

- 4........ ....

- 6.............

- 8.............

-10 .............

Jan.

1

1

 2

1

2

19

Feb.

,

2

:t

2

9

1

 >

19

Mar.

1

1

3

1

1

1

Apr.

1

1

2

1

1

1

........

17

May. June. July. Aug. Sept. Oct.

........ ........ 1 ........ ........ ........

........ ........ 1 ........ ........ ........

........ ....... 1 ........ ........ ........

........ i i e ........ ........

......... 1 4 S ................

........ 3121 ........

........ 4 ........ 1 4 ........

1 1 ........ ........ ........ ........

2 ........................ 8 4

2 ........................ 1 ........

........ ........ ........ ........ ........ 4

........ ........ ........ ........ 1 3

2 ........ ........ ........ ........ 3

1 ................................ 8

1

........ ........ ........ ........ ........ ........

................................................

: . i

Nov. Dec. Year.

1 : ........ ........

........ 1 ........

3 ........ ........

1 2 ........

1 1 ........

1 ........ .......

................ 1

1 9

........................

19 20 ........
SPECIAL CLIMATOLOGIC TABLES. 183

FREQUENCIES OF RAINY DAYS AT KILLISNOO.

The foregoing tables deal with the frequency of occurrence of various temperatures, but as no average or mean maximum and minimum temperatures bad been 

calculated there was no opportunity to compare these values, which are the ones 

usually given, with the most frequently recurring temperatures. In the following 

table of frequencies of numbers of rainy days at Killisnoo, direct comparison may 

be made between the most frequent number of rainy days in each month and the 

"Mean numbers" which are given in the last line of the table.

TaM« of/regrue»ci«i of (Ae number of (fay: Ammi^ O.OJ t»c% or more of rnw a< f%M:»oo. 

[From January 1,1889, to December 31,1902. The asterisk (*) Indicates mean number of days with rain.]

No. of days.

31 .......... .. ...

80.................

29 ...............

28 ...............

27 ..............

26.................

2R..... ............

24.................

23. ...............

22.................

2] ...........

20. ..............

19 ................

18.. .......

17.................

36. ................

15.................

14. ...............

13 ...........

12.................

11.................

10 .......

9.. .... ....

8 ..............

6 ..............

5...... .........

^

3.................

2.. ..............

0...... ........

Tears observed. . . . . 

Mean number of days

Jan.

1

1

1

8

1

*1

2

1

1

1

^

14 

18.0

Feb.

I

2

%

1

*

1

^ 0

1

1

1

1

14 

14.9

Mar.

1

1

^

9

*1

1

B

1

1

14 

15.0

Apr.

1

1

1

1

4

*

1

2

1

]

13 

11.0

May.

i

9

1

2

*

9

1

1

1

14 

12.3

June.

i

9

9

1

9

*1

9

1

1

1

14 

9.0

July.

1

1

1

*1

4

1

1

1

1

 

14

11.7

Aug.

1

1

1

1

1

9

*

S

1

1

1

1

14 

16.6

Sept.

1

2

1

»8

8

1

1

1

14 

19.3

Oct.

1

1

1

2

8

*1

1

1

1

2

14 

22.3

NOT.

1

^

2

2

*

8

2

1

1

1

]4 

16.9

Dec.

2

8

1

8

*

1

2

1

]

14 

17.6
184 GEOGRAPHY AND GEOLOGY OF ALASKA.

The table shows two facts very clearly, viz, that the same number of rainy days 

in a given month recurs much less frequently Ithan does a maximum or a minimum 

temperature; and second, that the mean number of rainy days does not necessarily 

coincide with the most frequently recurring number of rainy days. Concerning 

these relationships between means and ' Scheitelwerte" or most frequently recurring 

values, Professor Hann says" that when temperature "Scheitelwerte" for each ten 

years of observations, or even larger periods, are compared with the corresponding 

means, there is found to be " extraordinary variations among the 'Scheitelwerte' and 

a marked coincidence among the means." In April the most frequently recurringnumber of rainy days is thirteen, while eleven is the mean number of rain\' days as 

calculated in the usual way from the individual observations. According to the 

usual custom, April of next year should be expected to have about eleven rainy da}-s. 

A study of the April column, however, in this table shows that one-third of all 

the observations in April have shown thirteen rainy days as characteristic of April, 

whereas April has never had eleven rainy days, but has in four years had numbers of 

rainy days lying between six and eight. Then from the frequencies, as shown in this 

table, it would seem fair to conclude that the best chance for any given succeeding 

year is for April to have thirteen rainy days, and that the second best chance is for 

April to have a number of rainy days lying between six and eight, probably seven, 

and that there would apparently be no chance for April to have ten, eleven, or twelve 

rainy days, the number of rainy days lying closest to the so-called mean number of 

rainy days. We may illustrate this feature of these tables again by considering the 

number of rainy days in December. The mean, calculated in the usual way, assigns 

to December 17.6 rainy days. The table of frequencies, however, shows that the 

most frequent number of rainy days in December lies between nineteen and twentyone, with preponderating values for nineteen and twentj'-one. In other words, the 

chance would seem to be more in favor of December having twenty rainy days rather 

than seventeen rainv days at Killisnoo.

a Hann, J., Lehrbuch <Jer Meteorologie, Wien, 1902, p. 115.
SPECIAL CLIMATOLOGIC TABLES. 185

FREQUENCY TABLE FOR SITKA. 

FREQUENCIES OF RAINY DATS.

A table similar in character to the last one for Killianoo has also been constructed for Sitka as follows:

[Perlodfi: Nov. 1, 1867, to May 81, 1877; Apr. 1, 1881, to Sept. SO. 1887, and July 1, 1898, to Dec. 3], 1902. The asterisk (*)

Indicates mean nnmber of dayn with Tain.]

Number of days rain.

31 .................

30.................

29............ ..

28.......... ......

27.................

26.................

25 ................

24......... .... .

23. .............

% .......

21 ......... . ..

20.................

10... .........

18 ................

IT.................

16 ..............

15.................

14. ............

13.................

12.................

11 ......... . ..

10.................

9 ....

8.................

7.................

6.................

K. ................

4..... ........

3.................

2.... .......

1 ..............

Years observed ..... 

Mean number of days

Jan.

'l

1

2

1

^

8

1

»1

8

8

2

1

20 

16.8

Feb.

1

1

1

2

1

1

2

*

2

2

8

1

1

2

20 

16.9

Mar.

%

2

p

]

]

4

*1

]

1

]

1

2

19 

18.0

Apr.

1

]

1

8

1

]

8

*

3

1

8

2

]

21 

16.2

May.

]

5

]

2

*4

1

2

2

2

1

21 

16. 1

.Tune.

]

2

1

2

*2

1

2

2

2

20 

13.6

July.

1

2

2

2

2

*8

2

1

1

2

,

1

21 

14.9

Aug. Sept.

1 ......

1 .....

...... 1

1 2

.... 1

.... 1

1 .....

2 2

...... 2

2 8

...... *1

3 1

* 8

.... . 1

4 2

] . 1

3 ......

1 ......

1 :......

21 21 

16. 8 19. 6

Oct.

2

2

1

1

1

1

*1

5

2

1

2

1

20

21.7

NOT.

1

2

2

3

1

* 4

1

1

1

2

8

1

21 

19.6

Dee.

1

4

2

1

1

2

*1

1

1

1

1

1

1

2

1

21 

18.9

This table is for a period of twenty-one years, which coincides in part with the 

period of fourteen years used in the Killisnoo period. Here, again, the difference 

between the average number or rainy days and the most frequent number in each 

month may be seen moat clearly in the case of December, but also in October and 

March.
186 GEOGRAPHY AND GEOLOGY OF ALASKA.

FREQUENCY TABLES FOR COAL HARBOR, UNGA ISLAND.

Similar tables, compiled for Goal Harbor, are given below:

[Occurrence: During the Interval: Sept., 1889, to Sept., 1890; and Aug., 1891, to Oct. 16,

°F.

79...........

78..........

77...........

76...........

75. ...... ...

74...........

73..........

72...........

71...........

70...........

69...........

68...........

67...........

66...........

65...........

64...........

63...........

62...........

61...........

60...........

59...........

58...........

57...........

56...........

55...........

54...........

53...........

52...........

51...........

50...........

49..........

48...........

47..... .....

46...........

45...........

44...........

43...........

42...........

41...........

40..........

39...........

38...........

37...........

36...........

35...........

84...........

Jan.

......

::::..

i

3

4

......

1

Feb.

1

8

1

2

1

8

1

^

Mar.

1

1

1

2

1

1

1

Apr.

*1

1

1

4

2

1

1

1

1

Hay.

*1

1

2

4

i

i

i

i

June.

1

1

8

1

2

1

1

1

1

July.

1

1

*i

1

a

a

i

i

i

......

::::::

.....:

::::::

::::::

Aug.

*1

1

1

*1

8

1

1

1

1

1

1

Sept.

*1

i

8

2

8

1

2

*1

Oct.

1

1

1

4

3

2

1

Nov.

1

1

1

2

1

8

2

*1

Dec.

1

2

1

8

1

1

i

*i

2

Tear.

2

1

1

1

2

3

1

1

* Occurrences marked tbns indicate temperatures from daily readings at 7 a. m., 2 p. m., and 9 p. m. All others were 

obtained from self-registering instruments.
SPECIAL CLIMATOLOGIC TABLES. 187

Frequencies of absolute (or observed) minimum temperatures at Coal Harbor, Unga Island.

[Periods: Sept. 1, 1889, to Sept. 31, 1890, and Aug. 1, 1891, to Sept. 31, 1902. The asterisk (*) indicates values from daily

observations at 7 a. m., 2 p. m., 9 p. m.]

o j<

50...........

45...........

44...........

43...........

42...........

41 ...........

40...........

39...........

38...........

37...........

36...........

35... ........

34...........

33...........

32...........

31... ........

30...........

29...........

28...........

27...........

26...........

25...........

24...........

23...........

22...........

21...........

20...........

19...........

18...........

17...........

16...........

15...........

14...........

13...........

12...........

11...........

10. ..........

9...........

8. ..........

7...........

6...........

5...........

4...........

3...........

2. ..........

1. ..........

0...........

 1.. .......

2..... ...

- 4.........

- 5.........

6.........

- 7.........

 8..

- 9.........

-10.........

 11... ......

 12.........

Jan.

1

1

*1

1

1

1

*1

1

1

......

1

1

Feb.

1

2

1

*1

*i

2

I

1

1

1

Mar.

1

*1

1

1

1

1

1

1

1

1

*1

1

Apr.

1

1

1

1

1

2

1

* 1

*1

1

1

May.

1

2

2

1

1

1

1

1

1

]

June.

1

2

2

1

3

1

1

1

July.

i

--

3

3

1

Aug.

*1

1

3

3

2

2

1

Sept.

......

1

6

2

2

2

. 1

Got.

-

--

2

1

2

1

1

2

2

1

"

Nov.

'

1

*1

1

1

3

2

2

1

Dee.

1

1

1

1

1

1

1

1

1

*1

1

Year.

1

1

1

2

2

1

1

1

17211 No. 45 06- -13
188 GEOGRAPHY AND GEOLOGY OF ALASKA.

Table of frequencies of days having 0.01 inch rain or melted snoiv in each month, and the year, at Coal

Harbor, Unga Island.

[From Jan. 1, 1894, to Dec. 81, 1902.]

Number of days.

25 .................

2 1 .................

23 .................

22 .................

21 .................

20 .................

19 .................

18 .................

17.................

16.................

15.........----.-..

14 .--..--....-.--..

13 ..------...-.....

12 .................

11 .................

10 ..-.--.........-.

9 .................

8 .................

(i .................

5 .................

4

3 .................

2 .................

1 .................

0........ .........

Mean number days .

Jan.

L

2

2

2

1

1

14.5

Feb.

2

2

1

1

1

13.0

Mar.

1

 2

1

1

1

1

 >

14.0

Apr.

:

1

1

1

1

1

1

1

1

13.2

May.

1

1

3

1

1

2

11.8

June.

1

1

1

2

1

1

1

------

10.4

July.

2

2

1

3

1

10.6

Aug.

:

1

1

2

1

1 '

1

1

13.6

Sept.

1

2

1

1

1

1

1

1

15.9

Oct.

2

1

1

1

1

1

1

1

16.4

Nov.

1

2

1

1

1

1

1

1

14.4

Dec.

1

1

1

1

1

1

1

1

1

13.8

RAINFALL AT ALASKA STATIONS.

In the rainfall tables the following abbreviations and symbols are used: ( ) inclose figures not used

in compiling synoptic tables; ? signifies figures whose accuracy is doubted; indicates that the 0.30 0. 30

inch fell on the days from 5th to 31st, both inclusive; > indicates that the sum following is, from the

original records, evidently too small; < indicates that the sum following is probably too large; 25_da.

0.75

indicates that the given sum (0.75 inch) is from 25 observations only during the month and therefore incomplete; R2.65 indicates that the number shows only rainfall, snowfall not, included; [0.73], 

an interpolated mean. Where the fragments of two successive years overlap by one or more months, 

as in the case of Nuchek, the averages only of the duplicating months were used in determining the 

annual rainfall.
RAINFALL RECORDS. 189

8'iniimarij of records oj'precipitation (in inches) <it stations in Alaska,.

ANVIK. 

[Lat. (12° 37' X. Long. 160° 08' W.]

Year.

1 SKi

Jan. Feb.

0 '!') 0 59

Af»r.

20 da

l.TO

1.78

Apr.

0. 40

0. 98

May.

27 da

0.51

0.47

June.

/i-n

V0.467

.Inly. AllR.

/11-3U

\ 2. 75 7

Sept. 

/12da\

\ 0. 48 7 

3. 33

4-30

2.31

Oct.

 > 43

Nov. 

2. 20

1 40

Dee. 

/20da\

\0.17J

(

18da\

0.307 

/1-17X

\0. 587

Annual

ATKA ISLAND. 

[Lat. 52° 15' N*. Long. 17-1° 15' \V.]

1882.............

1885.............

11.45 

7.65 

8.01

9.18

4.49

8.20 

3.43 

10.31

3.94

8.40 5.40 4.47 4.40 

3.60 4.86 8.19 4.20 

7.14 5.97 6.46 5.10

7.08 7 07

4.63

3.88 

11.62

2.01

ATTU ISLAND. 

[Lat. 52° 58' N. Long. 172° 21

1881 .............

1884 .............

1885.... .........

5. 29

0. (il

0. 94

0.58 

0.66

1 WSQ

3,01

2.98 

1.49

0.89 

1.50

0.68 2.08

BERING ISL 

[Lat. 52° 12' N. Lonf

................ ( 2 -*\ 2.07 \ o 7

0.61 1.03 0. 3« 2.71 

1.44 1.38 1.31 0.20

0.25 0.86 1.19 1.63

/22-3U 

\ 0 7

VNI).

'. 165° 5"

1.45

2. 09 

2.27

4. 05

5. 43 

4.83 

3.78

(i.30

' W.] 

4.62

1.07

3.43 

1.71 

30 da

2. 15

CAMP OOLONNA. 

[Lat. (17° 25' N. Long. 141° 00' W.]

0.81 0.12 0.60 0.27 / 1-14 *

\ o.oi 7

9.16 

9.71

8. 20

(i. 30 

12.18 

10.05 

12.74

4. 06

1.32

3.67 

1.70

3.32

8.91

10,90

8.87 

14.72 

11.85

6.46

13.46 ........

2. 52 85. 11 

8. 85 ,H;i. 97 

6. 26 97. 44

8. 29

2. 52 

3. 26

1.34

/13-3U 

I 0.17 7

2.23

2. 16 

3.39

4.08

2.21 ........

1.72 23.91 

0. 96 20. 11

1.61 21.45

0.41
190 GEOGRAPHY AND GEOLOGY OF ALASKA.

Summarii of records of precipitation (in inches) at stations in Alaska Continued.

CAMP DAVIDSON. 

[Lat. 64° 40' N. Long. 141° 00' \V.]

Year.

1890 .............

Jan.

0.59

Feb.

0.80

Mar. Apr. May. June.

( t

\0.48/

July.

1.74

Aug. Sept. Oct. ' Nov. ; Dee. Annual.

13.42

CARMK1, MISSION (NUSIIAGAK). 

[Lat. 58° 57' N. Long. 158° 21' W.]

1.98 ........ 0.40 3.00 ........

1

CHERNOFSKI.

[Lat. 53° 25' N. Long. 107° 14' W.]

1881 . 7.24 0.70 . >0.50

CHILKAT (PYRAMID HARBOR). 

[Lat. 59° 20' N. Long. 135° 25' W.]

1*^84

1880

3.30

0.08

0.76

4.90

0.93

5.75

1.80 0.71

0.09

2.94

0.08

0.32

1.05

0.32

1.60

1.14

0.01

2.19

1. 52

0.31

5.11

2.44

0.45

1.98

2. 58

3.30

4.79

7.17

1.14

5.23

1.51 11.30

CHILKOOT (PORTAGE BAY). 

[Lat. 59° 20' X. Long. 130° 28' W. Station probably located near the present Haines Mission.]

81 .............

8.77 ' 18.99 1.34

5.93

3. 04 1. 55

1.13 ........

2. 45 1.95 2.94

/18-3U

I 2. 28 / 

8.00

0.85

7. 55 10. 31 5. 52 72.41

CIRCLE. 

[Lat. 65° 50' N. Long. 144° 04' W. The accuracy of queried values is doubtful; they are one-tenth of recorded snowfalls.]

1897............. (1.53?

1898............. (0.20?

0. 10?

0.40?

0. ?

1.60?

0.20?)

1.10?

0. 75?

1.45?)

0. 75?)

0.70

0.39

2.30

1.60

(1.50?

2.72

1. 65? 1.15? 0. 10?

(0.50?

0.40?)

0.40?)

COAL HARBOR, UXGA ISLAND. 

[Lat. 55° 20' N. Long. 100° 38' W.]

I CQO

1894 .............

1895 .............

1890 .............

1897.. ...........

1898.............

1899 .............

1900 .............

1901

1902.............

3. 05 1. 50

2.91 3.08

1. 02 B. 08

4.90 ' 5.00? 

6.59 ' 1.39

3. 30 3. 77

3. 37 5. 41

6. 54 4. 64

2.74

5.42

2.88 

8.70

4.28

2.22

1.99

5.34

0.91

8.00

1.09

3.85 

3.21

1.82

18.28

3.55.

4.77

5.20

2.09

2.74

0.71 

2.02

3.72

2.24

0.67

2.98

4.40

1.09

2.15

2.35 

7.08

0.39

1.88

2.21

0.33

0.88

2.40

3.93

1.70 

3.59

6.51

2.91

1.64

1.70?

5.17

3.17

6.79

1.40 

2.23

4.42

5.74

1.03

3.06

4.21

2.03

11.41

3.70 

1.07

4.99

4.65

2.80

5.88

4.48

8.15

5.23

0.82 

0.73

5.06

5.36

7.45

4.74

5.89

7.30

2.00

12. 90 

0.04?

1.91

7.98

3.54

0.87

5.55

4.46

3.79

6.82 

3. 71?

1.25

3.21

8.87

1.20

52. 23

53. 15 

40.90

41. 42

44.87

48.04

a The exposure of the ram gage changed on the 1st ot this month.
RAINFALL RECORDS. 191

1881

1882

1883

1884

1885

1886

Summary of records of precipitation (in inches) at stations in Alaska Continued.

COPPER CENTER. 

[Lat. 61° 58' N. Long. 145° 20' W.]

Year.

1902.............

Jan. Feb. Mar. Apr. May.

.......

June. July.

/ 18-31 1

\ 0. 90 )

Aug.

1 OS

Sept.

0.73

Oct. Nov.

 > Q._2 ' 1 tuj

Dec. Animal.

1901.

1902 .

1885

1886

EAGLE. 

[Lat. 64° 45' N. . Long. 141° 10' W.]

1886.............

189*J

0 28

0.45

0.70

1.23

1.01

0 36

0.44

1 1 Q

0.42

(~-\ \ o ;

/1-12X

\ 0. 21 /

/ !-19 \ 

(0.47)

0.64

........

........

........

1.57

1.15

1.88

,22-SU

\o.wt

/16-3H

\0.48/

/16-31\

1, 1. 68 )

2.71

1.28

1.65

fl Qfi

0 39

1.72

0.27

1 32

0.65

1.23

0.77

0 38

1.27

0.52

0.21

0.40

0.26

0.77 12. 28

O9.19)

FORT ALEXANDER. 

[Lat. 58° 57' X. Long. 158° 21' W.]

4.80

0.26

1.06

1.42

1.24

0.00

1 63

2.72

4.21

2. 85

0.47

1.49

3.41

1.76

3.12

2 39

1.18

2.24

/15-30v

\ o. w)

2.21

(J-l?\

\ 0. 62^

2.86

6.10

3.90

2.19

8.99

5.33

4.16

1.91

3.58

2.13

6.53

0.43

1.44

1.46

I 35.05

j

FORT LISCUM. 

[Lat. 61° 05' N. Long. 146° 20' W.]

y.40 0.80

1.28

6.38 6.20

4. 70 2. 80

1.45

3.08

1.13 ! 4.77 

0.24

16.20

8.56

12.72

15.72

10.31

18.20

7. 47 

4. 43?

83. 11

FORT RELIANCE. 

[Lat. 64° 10'N. Long. 139° 30'W.]

0.27

1.24

0.32

0.08

1 ^\

\0.00^

/l-29v

IbTeli)

0.80

/17-30V

\ T. I

0.48 0.71

0.44

« Records kept at Fort Egbert military post.
GEOGRAPHY AXD GEOLOGY OF ALASKA.

ij of records of precipitation (in inches) at stations in Alaska Continued.

FORT TONXJAS8. 

[Lat. 54° 46' X. Long. 180° SO' \V.]

Year.

1889 ........... 

1870.............

Jan.

12.00

Feb.

9.98 

11.61

Mar.

5. 75

Apr.

9. ,87

May.

5.80

June.

1.81

6.89 

4. fi3

.Tul.v.

8. 45

5.87

Aug. i Sept.

0.45 ' 2.78

6.44 ' 12.51

Oct.

8. 68?

19. 54

Nov.

13. 00

Dec.

10.40

16. 26

Annual.

123.41

1868 .

1869.

1870.

1876 .

1877 .

1881 .

1882 .

1900

1901

1902

1895

1896

189X

1902

FORT WRAXGELL. 

[Lat. 56° 28' N. Long. 132° 20' \V.]

3.4H

8.71

2.26

12. 92

9.14

1. 25

3.54

3.87

7.27 

2.94

2.13

/8da\ 

U.39/1

I" }

\ 0. 90 /

5.11 

2. 63

3.39

(

21 da\ "i~4«/

1.90 

5.06 

3.90 

[3.56]

l-~U \

USS/

3.40

4.20 

4.60 

2. 35 

2.56

4. 76

I 00

3.50 ' 6.66

/ 1-26 \ 3. 05 I I

U4.02/

4.91 , 5.16

/25-31\ ( I ,s. 06

\ 0.137

11.13

5. 76

5. 19

3.69

11.75

18.37

........

7.39

12. 36

11.49

i 56.00 

I 76.75

FORT YFKOX. 

[Lat. 66° 34' N. Long. 145° 18' \V. This record seems to be of doubtful accuracy.]

0.36

1. 95?

0.88?

T

0.01?

0.42?

0.05?

0.56

0. 58?

30 da

i.~J7

16-30

5710 

28 da

0. 74

0.60?

0.60

0.27?

0.24

0.75?

GAMBELL (ST. LAWRENCE ISLAND). 

[Lat. 63° 50' N. Long. 171° 25' W.]

........

........

>0. 60?'. .......

0. 14?

>0.35

0.59 

>1.26

0.59

29 da

26 da 

0742" , l ' 08 

0.89 ' 3.63

0.42 1.67

! 25 da J' U i:75

1.92

>2. 66 

1-25 

I. 56?

26 da 

T. 23

0.48? 

>0. 75?

>2. 50°
RAINFALL RECORDS.

Summary of records of precipitation (in inches) at stations in Alaska Continued.

HOLY CROSS MISSION. 

[Lat. 62° IB' N. Long. 159° 50' W.]

193

Year. Jan. Feb.

1893 .....................

1897 .....................

1898 ] 94'^

1899.............! 0.51?

1900 ' 0 74"

0.56 

1.03 

29 da 

1.07?

1.07? 

1. 05? 

29 da 

~O.TK 

2. 40

Mar, Apr.

1.81 0.52 

1.37 | 0.11

1.34 1.67

>3.29 >1.21 

1.497, 0.97?

0. 50 0. 50 

!.',(>? 0.65

[Lnt.

May.

0.21 

0.37

0.20

0.20 

0.33

0.92 

0.13

June. , July. Aug. Sept.

i '

1.75 ......... ........

0. 99 2. 19 2. 65

1.98 ' 2.63 ] 3.90

f<22 da 

0.46, 1.14 -^-jg

2.89?' 3.34 2.96 

3 67

1.67 ! 1.44 5.76 

0.85 1 0.92 4.50

1.79 

1.71

1.83 

"25 da 

1766? 

2.43 

4.40

6.69

Oct.

5 ns

2.12 

0.69

1.45

0.28 

1 . 17?

3.31

Nov.

0.67 

0.55 

2.23

1.04

1.19?

0.49

1.98

T)eo_. 'Annual.

3.57 ........

0.59 14.72

1 17.37 

1.79 )

1. 15?>21.90? 

1.00 '........

4.49? 28.60?

HOWKAK. 

54° 4.V X. Long. 132° SO' W.]

1 25 da

18. 56?

26 da 

14.21?

28 da

19.63?

JUNEAU (1). 

[Lat. 58° 19' N. Long. 134° 28' \V.]

1881 .

1882 .

1883 .

1884 .

1889 .

1890.

1891 .

1892 .

1894 .

1895 .

1896.

1897.

9 50

10 94

29 da

5.40

2.68

5.08

5.25

9 64

5.89

5.68

4.49

4.94

7.46

23 da

3.87

8.98

/17-30V

\ 8. 63 /

9.41

5. 51

2 37

3.23

11.23

8 no

2.21 17.11

7.53

14.08

U

oq

,/i3-;«n

' ' , \ s. 15 ;

11.19 10.44

/16-30\

\ 8. 27 /

12.05

7 °v(

107. 65

95. 76

........

JUXKAU (2) (WHARF). 

[Lat. 58° 19' N. Long. 134° 28' \V.]

1898.............

1899..-...--.-.-. 

1900.-.-..-.-..,.

1902

4.22 

8.52

9.57

4.92 

4.19

6.32

2.08

1.58 

3.06

4.28 

11.37

8.19

4 34

4.68 

5.00

3.47

5/63 ' 1.06 4.88

12.10

9.10

11.41

14.24

11.90 

10. 91

6.57

6.71 

12.45

3.52

7.38

8.10 ........

8.42 ; 67.38

4.2(1 83.37

a These values not used in computing total for 1896-97.
194 GEOGRAPHY AND GEOLOGY OP ALASKA.

Summary of records of precipitation (in inches) at stations in Alaska Continued.

IKOGMUT (Russian mission). 

[Lat. 61° 56' X. Long. 160° 43' W.]

Year.

1886.............

1886.............

Jan.

0.58

/23-3U

\ 0. 00 1

Feb.

29 da

0.65

0.20

Mar.

1.48

1.68

Apr.

0.81

0.71

O.S1

May.

/ \

\o.si;

5-31

3.13

June. July. Aug.

/18-3U

\ 2. 85 ) 

/16-3H

\0.98/

Sept.

27 da

5.17

5-30

0.98

Oct.

5.69

9-31

0.09 

1.53

Nov.

3 94

1.07

Dec.

1 50

0.65

l~\ \o.9i;

Annual.

........

KENAI. 

[Lat. 60° 32' N. Long. 151° 19' W.]

1883.............

1884.............

1885.............

1886.............

1899.............

1900

1901.............

0.71

1.15

1.47

0 64

0 84

29 da

0.96

1.87

0 31

1.30

0.85

1.50

0 31

0.32

0.50

27 da

0.37 

1.43

1.24

1.03

0.37

0.30

[0.73]

0.60

0.55

0.59

2 21 1.56

2.79

4.80

2.34

2.92

/12 da\

' 1.33/

1.16

3.34

2 23

4 69

27 da

0.92

2 85

0.41

1 37

4.32

1.69

1 99

1.14

0 32

0.86

0

01

0 95

1.61

0.67

1.55

>13.61

18.53

KETCHIKAN. 

[Lat. 52° 25' N. Long. 131° 38' W.]

23-31

2.79

3.31 5.62

KILLISNOO.a 

[Lat. 57° 22' N. Long. 134° 29' W.]

1881 .

1882.

188S .

1884.

1885 .

............. 

.............

. .....

6.38 

1.69

29 da 

1.85

[5.6] 

(Recor 

2.05 

4.45

7.01 

1.01

[5.0]

ds oxist 

29 da 

Tl5 

3.35

1.61 

3.25

1.88 

1.17 

0 50?

3.36 

d for th 

2.30 

3.45

0.48 

s year, b

3.40

20 da 

5.00 

2.47

0.82

28 da

oTei"

ut coulf

2.95

1.36 

2.02

2.47

>1.29 

8-30 

0.49? 

7-30 

0.57 

not be

1.85

2.68 

2.78

30da 

2.44

0.87 

1.00?

1.54 

ound.)

1.85

2.09 

2.38

4.87

4.13 

2.05?

4.05

6.40

29 da 

8.79 

3.44

3.70

3.49 

4.89?

5.85 

7.35

3.03 

25 da 

0.55 

28 da 

2.85

6.61 

6.29?

9.85

10.78 

4.70

7.13 

21dft 

>1.10 

1-16 

2.88 

22 da 

6.39

8.25

8.55 

4.75

7.97 

3.19

3.67

5. 55

3.85 

2.40

[94.1]

[51.0]

.14. Ml

a The values on pp. 1B2-165 are based on the years 1889 to 1902 only.
RAINFALL RECORDS. 195

Summary of records of precipitation (in inches) at stations in Alaska Continued. 

KILLISNOO Continued.

Year.

1897 .............

1899 .............

1900 .............

1901 .............

1902 .............

Jan.

2.05

8.35 

8.40

8.10

5.85 

3.25

7 50

5.45? 

4.40

6.41

6.95 

29 da 

6.95?

Feb.

4.60 

2.70 

29 da 

7.80 

8.70 

8.25 

7.30 

29 da 

8.25 

8.40 

3.80

4.80 

29 da 

3.35 

6.05

2.65

Mar.

4.20 

7.05

9.30

3.65 

7.70 

2.50

2.30

2.70 

2.45

2.00 

2.40 

5.40 

1.50

1886............. 2.06

Apr.

0.90 

5.95

[3. ,50]

8.80 

4.20 

4.20

0.65

4.35 

6.80

1.60 

6.85 

1.15 

2.10

[Lat

0.98 3.40 2.25

May.

2.40 

4.40

3.25

5.35 

2.85 

1.70

0.80

8.40 

2.90

1.40 

2.20 

4.00 

4.70

KISI

52° 00' 1

13-31 

1.94

June.

0.30 

0.40

4.60

2.85 

3.15 

3.35

3.25

1.50 

1.05

3.20 

4.30 

1.60 

1.60

July. Aug.

6.02 

3.35

5.95

8.15 

8.95 

3.35

2.05

5.30 

4.30

0.90 

8.45 

1.40 

3.80

1.95 

6.65

6.75

9.90 

5.60 

6.95

3.40

4.65 

1.30

1.95 

2.30 

5.95 

4.80

Sept.

12.80

8.25

9.55

8.35 

5.05 

6.45

8.95

13.15 

6.35

7.40 

4.25 

5.50 

7.20

Oct.

7.55 

7.95

12. 45

9.60 

6.15

8.45

10.55

11.95 

5.90 

30 da 

5.95 

6.00

9.10 

4.60

Nov.

8.80 

3.24

9.80

4.10 

5.35 

4.45

1.30

4.25 

6.50

6.30 

7.05 

8.55

2.75

Dec.

3.00

5. 20

13.25

4.95 

4.05 

8.55

8.25

4.60 

6.95

3.45 

6.50 

5.30 

2.90

Annual.

54.57 

63.49

[94. 10]

72.00 

62.15 

60.50

57.25

69.70 

52.70

45.36 

59.20 

55.95 

45.55

CA ISLAND. 

<f. Long. 177° 25' E.]

3.88 6.89 8.10 4.31

................

7.67 6.28 2.55

i>51. 26

KODIAK (I). a 

[Lat. 57° 48' K. Long. 152° 25' W.]

1869 ............. R2 65 E4 11' R9.83 6.86 8.68 0.79? 8.89 5.94 7.14 6.61 9.90 73.56

KODIAK (2) (WOODY ISLAND). 

[Lat. 57° 48' N. Long. 152° 25' ? W.]

1901 .............

5-31

2.95 

2.62 0.80

6.29

7.46

3.85

4.33

29 da

2.60 

/19da\

\4.20?)

6.62 3.35

1.55

30 da

6.64 

3.56

1.87?

2 64

5.13

6.15?

5.98

/25 da\

V3. 13?/

/25 da\

1 1. 86 )

8.95 4 82

/24dav

\ 0. 75 /

/27dav

U.20J

a The values on pp. 162-165 are Jor 1898-99 only.
196 GEOGRAPHY AXD GEOLOGY OF ALASKA.

Summary of records of precipitation (in inches) at station* in Alaska Continued.

KOLMAKOF. 

[Lat. «1° 30' X. Long. 158° 59' \V.]

Year.

1884

188(i ....... .....

.Tun.

1 34

,17-31v

\ 0. 39 ;

a 22

Feb.

1. OS

29 da

0.29 

0. 12

Mar. i Apr.

i 

/22dav /27da\

\ 0. 56 7 ' \ 0. 60 7

\1.0,V

May.

/18da\

I 0. 07 7 

/22<1iu

Vl.27/

('"-)

lo.GS/

June. July.

,10da\

- - \ o.ii7

,6-3U

V2.307

Aug.

/21 dav

I 3. 85 /

80 da

7.36 

(17 dav

1.17/

15.6V/

Sept.

27 da

2.43 

4. 54

II 8-30 v

\ 0. 03 7

Oct.

1.14

/20 dav

\ 0. 94 /

30 da

0.06

Nov.

/19da\

\10. 97/

/21 da\

\0. 93 /

Dec.

27 da

3. 65 

1.11

1 ~ \

\0. 297

Annual.

METLAKATLA.

[Lat. 55° 10' X. Long. 131° 30' X.]

1891 ..'...- i .. . ....

3 41 10 84

4. 27

 > S3

I 

JIORZHOV

4.73

JI.

[8.2]

18. 75

12.81

[15.8]

14.31

[11.2] _..,

18.00 ........

j-> 71) 119 1 !

114 HI MIS 91

[Lat. 55° 03' N. Long. 163° 10' W.J

\ 0. 90/

0 49

ft. 56

8-31 

2.67

5.02 7.51

8 38 > 'Al

1-27

10. 26

7.47 0.60

NOMK.

 [Lat. 64° ;»' TV Long. 165° 25' W.]

1900 ............ . . .. i .......... ... . .

!

...... . 7.00

0.60

NUCHEK. 

[Lnt. 60° 23' N. Long. 146° 40' W.]

1883............. ................I........ ......... 13.00

18.02 ' 16.92 24.84

9.15

6.47 8.72 10.81 ' 22.96 21.50 10.51 I 16.81

1.88 ' 11.14 i 17.46 190. 09

NDLATO. 

[Lat. 64° 41' K. Long. 1.57° 58' W.]

1 QQO

1895 .............

1896 .............

'

T

29 da

0.73

0.89 0.16

\0. 277

........

........

0 36 ,1-8,

\0.24'

2. 62 ' 3. 76

1

/1-16V \ o / --------

1.42 ........

',
RAINFALL 197

Suminani of records of precipitation (in indies) at station.*; in Alaska Continued.

OMALIK. 

[Lat. 65° 02' X. Long. 162° 40' \V.]

Year,

1885 .............

Jan.

/20-3U

\ 0. 57 /

0 40''

Feb.

29 da

0.23 

0.40?

Mar.

0.09

>0.21?

Apr.

0.07

/ 1-16 \

V0.32'/

May. June. July. Aug. Sept. Oct. Nov. Dec. Annual.

ORCA.

[Lat. 60° 35' N. Long. 145° 40' W.]

1900

1.21

15. 74

16.91

0.60

16.35 13. 70 4. 59 5.06

30 da

3.C2

11. 25

30 da

27.02

/13-30\

\14. 307

15. 32

/17-30\

\12.7lj

17.87

9.78

24.71

35. 56

13. 02

4.72

9.95

13.09

11.40

129. 31

POINT HOPE (NEAR TIKIEA). 

[Lat. 68° 25' N. Long. 166° 38' \V.]

S94

0.05

0.03

29 da.

0.04

0.19 0.27

1 49

28 da.

1.59 

30 da.

0. 45

1.19

1.77

0.42 1.37

0.13

3.22

ST. MICHAEL. 

[Lat. 63° 28' N. Long. 162° 10' W.]

S78 .............

ISO .............

881 .............

S82 .............

S83 .............

0.06

1 88

2.63

0. 57

0 43

29 da

0.17

0 34

0.12?

0.78

1.07

0.46

0.44

t) 04

0.50

0.77

2. 59

0.68

1.40

0.65

0.26

1.84

0.77

3.51

1.77

/15-3M

\ 0. 67 /

3.48

0.65

0.89

( 1 " 16 )

\ 0. 17/

3.13

4.00

2.16

4. 05

4.43

/27-3H

\ 1). 17 /

1.40

2.29

5.61

3.40

4.48

5.04

3.39

0.66

2.38

2.14

1.74

1.66

1.46

1.62

0.95

1.48

1.75

1.27

1.06

0.60

0.42

1.86

1.31

0.23

0.70

0.20

0.75

18.18 

[20.1J 

16. f.l

[13.66] 

21.73 

15.50

20. &« 

[18.Ij
198 GEOGRAPHY AND GEOLOGY OF ALASKA.

Summary of records of precipitation (in inches) at stations in Alaska Continued.

ST. PAUL ISLAND. 

[Lat. 67° 15'N. Long. 170° 10'W.]

Year.

1878 .............

1882.............

18926............

1893 b. ...........

18946............

Jan.

1. 00?

7 32

2 54

1.62

"^ 2 46?

Feb.

3.00

0 48

2.86

Mar.

0. 82?

1.92

2.88

4.18

3 79

Apr.

1.10?

1.71

3.28

2. 29?

May.

1.68

2.10

1.85

June.

0.14?

1.02

1.76

->2.22?

July.

29 da

2.73

3.49

2.55

>1. 99?

Aug.

........

2.30

1.96

>1.93

Sept.

/20-30\

\ 1.23/

7.94

3.88

Oct.

1. 92?

6.55

2.91

R

Nov.

2. 40?

7.81

Dec.

8.14

3 04

>2.99?

Annual.

,

i 36. 59

>28. 21?

SITKA. 

[Lat. 57° 03' N. Long. 135° 19' W.]

868.............

869.............

8/2.......-..---

874 .............

876 .............

882

886

887 .............

899.............

900

901 .............

902

........

7.00

3.00

2.74 

3.06

9.03 

9 98

7.83

8.71

29 da.

6.05

29 da.

2.07

5.87 

7 90

29 da. ~~2.89

16.35

6.92

29 da.

6.15 

9.86

4.92

10.38

2.25

5 72

6 00

4.74

o. oy

2.27 

r~i 94

4,29

[6. 70]

2.62

7.80

5.39

2 27

8 99

4.00

2.83

2.23

3.72

4.78

2.76

13.42

6.64

8-30

3.76 

12.09

7.17

4.93

1.67

2.04 

1.69

3.19

3.10

2.89

3.70

10.35

3.55

3.68

7.30

4.02

4.56

4.86

6.10

1.93

4.99

4.94

6.00

2.67

3.43 

3.14

2.62

1.54

4.13

3.77

2.36

4.53

5.01

/15-3U

U.39J 

J.99

3. 13

1.26

1.87

4.20

3.20

2.44

2.79

1.54

3.40 

3. 57

3.12

4.40

6.68

6.38

3.85

3.27

7.62

3.97

2 27

3.77

0.45

7.35

4.01

3.84

7.54

2.50 

5.30

5. 52

1.98

9.16

4.00

10.72

9.38

3.92

8.35

7.92

10.03

14.96

7.62

5.09

15.70

 6.36

12.11

8.13

8.33

25. 52

10. 55

5.98

8.52

28 da.

/. 82 

8.82

13.43

7.27

9.50

9.46

14.84

9.82

6. 04

13.31

13. 55

24. 82

(-±±\

\1.6l)

8.22

9.85

10.73

15. 59

8. 25

9.38

7.12

9 02

4.84

9.15

13.50

11.47

10.63

9.65

20. 51

13.47

7.02

9.39

6.16

6.19

6.69

7.55

5.75

10.27 

11.66

17.97

14.54

7.09

11.70

3.26

6.94

6.59

10.18

5.93

94.21

"~ft lo

70.13 

83. 75

77. 08

102. 26

140. 26

[78.7]

80.82

88.03

88.57

"These observations were recorded, in cubic centimeters (ce), and have been converted to depth of rainfall in inches 

by multiplying by Tg0 . This factor was obtained by assuming the rain gage to have been a De Witt conical 9-inch gage, 

with 5-inch aperture, sucli as was regularly supplied to the U. S. Army post hospitals, and by assuming that the rainfall 

was poured from the gage into a glass graduate reading in cubic centimeters.

6 The records for these years not used In compiling the synoptic tables.
RAINFALL RECORDS. 199

ii of records of precipitation (in inches) at stations in Alaska Continued.

SKAGWAY. 

[Lat. 59° 28' X. Long. 135° 20' W.]

Year.

1898

1900 .............

Jan.

0.86

Feb.

0.88

Mar.

1.15

Apr.

0.66

........

May.

1.07

0.12

June.

1.29

July.

1.70

2.89

Aug.

T

3.03

Sept.

5. 28

/14-30\

ll.22)

Oct.

4.92

Mov. Dec.

7.85

1.44

2.06

Annual.

[>17.99]

'

1882 .

1883 .

1884 .

1885

1886 .

TANANA (FORT ADAMS). 

[Lat. 65° 10' X. Long. 152° 45' W".]

1.72

3.16

1.22 0.40 0.40 /1-22V

\0.67/

1.51 ........

/18-31\

\ 0. 23 )

1 7->

1.10 2 59 2.75 0 8*1

TAXANA (FORT GIBBON). 

[Lat. 65° 12' X. Long. 152° 00' W.]

1.57 0.14

1898

1899

1900

1901

1902

TELLER (KEIKDEER STATION). 

[Lat. 65° 20' X. Long. 168C 30' Vv .j

1901

1902 ............. 0.01 0.09 0.20? 0. 00?

TYONOK. 

[Lat. 61° 03' X. Long. 151° 10' W.]

.............

.............

1.29

2. 69

1. 55 

3.08

0.20

0. 52

0.47

0. 62

0.60

1.00

0.71

0.29

0.04 

0.38

0.72 1.05 4.94

0.53 , 2.68 5.77

5. 51

4.22

3. 16

6. 56?

4.70

4. 42? 

4.96

1.85

0.60

0. 45

0.73?

1.13

22. 70

20.17

21.55

28.29

FGASHIK. 

[Lat. 57° 35' N. Long. 157° 50' W.]

18X3. .......... .- 

1884 ............. 1.66

1.22

/ 1-m

\2. 53? /

29 da.

0.34

1.00

1.75

28 da.

1.26 

1-26

1.74

0.21 2.72

(5.19) ...... ..........

2.26 , 7.05 2.99

4.77 3.99 , 2.41

2.07

0.78

........

(0.91) 

1.12
200 GEOGRAPHY AND GEOLOGY OF ALASKA.

of records of precipitation (in incites) at stations in Alaska Continued.

UNALASKA. 

[Lat. 58° 52' N. Long. 166° 31' W.]

Year.

1881 .............

1883 .............

.1884.............

Jan.

2.88

14.30

17.78

15.82

Feb.

1 3*5

 j 09

7.97

29 da.

26.19

Mnr.

3.26

o 84

Apr.

1-28

2.93

1.18

2.19

5.77

14.00

12.40

14.09

May.

4.51

3.97

1.47

( "'"'I

\ 3.71^

June.

3.84

12.41

2. 03

July.

2.12

1.70

4.31

4.15

Aug.

' '

1.88

4.74

4.90

3.34

Sept.

2.59

17-31

0.37

9.16

11.48

9.75

11.23

7.64

Oct.

3.97

27.30

10.00

6.15

11.85

17.60

Nov.

6. 56

9.30

5.02

19.89

8.75

Dec.

7.37

28. 17

8.08

Annual.

80. M)

90.12

158. 29

108. 17

UTKIAVI (GOVERNMENT STATION NEAR POINT BARROW). 

[Lat. 71° 17' N. I.ons. 156° 40' W.]

mi. ............

1 SK'i

1901 .............

1902.............

........

O

il

T

0.04

0.84

<0.20

........

0.14

<0. 05

0.41 0.44

T

0.63 1.47

1 04

1.51

1.46

0.48

I/17-31V

 { 0.9<V 

1.10 1.09

0.13? 0.42?

0.73

0.34

0.10?

0 44

0.24

<0. 10?

8.18

,

3. 45

GEOLOGY.

INTRODUCTION.

This report as first projected was to include descriptive geography only, and no 

geology; but as the work advanced it led to a consideration of the origin, as well as 

the distribution and form of the topographic features. Once having entered this 

borderland between the two sciences, references to the bed-rock geology multiplied, 

and a systematic presentation of the purely geologic aspect of the problems seemed 

desirable. As no summary of Alaskan geology has been published in recent years, 

it will be necessary to cover the entire field. In such a brief review only general 

results can be presented, and the details must be sought in the reports which will be 

referred to. It is hoped that a short account of the geology may not only lead to a 

better understanding of the physiography, but may also serve a useful purpose in 

presenting a resume" of the progress of geologic investigation in this important 

section of North America.

Though geologic investigation can be said to have been begun by Steller, who, 

as a member of the Bering expedition in 1741 (p. 107), was the first naturalist to land on 

the Alaskan coast, only within the last decade have systematic researches been undertaken. Most of the exploring expeditions, of which an account has been given 

elsewhere in this report (pp. 104-133), were accompanied by naturalists, who usually
GEOLOGY. 201

noted the rocks and minerals encountered and collected fossils. Chamisso, the German poet-naturalist, in 1816 accompanied Kotzebue on his voyage of discovery, and 

was one of the earliest contributors in this field.

As the coast became better known these observations multiplied, and the 

collections which found their way to European museums gave the stratigrapher 

some clue to the character and age of the bed-rock terranes; but at best these notes 

were scattering and were often by untrained observers. In 1848, Grewingk a admirably summarized all this earl}' work in a compilation based on an exhaustive study 

of the literature, and not only assembled all the facts conveniently in one volume, 

but also presented some suggestive correlations and generalizations. This was the 

first attempt at a S37 stematic treatment of the geology, and the results even at the 

present day are not without value. Grewingk must be credited with the first 

geologic map of any part of this province, and he seems also to have been the first 

to obtain any true conception of the relation of the orographic features of Alaska 

to those of the rest of North America.

A quarter of a century elapsed after Alaska passed into the hands of the United 

States before the casual notes of the naturalist were supplemented by systematic 

geologic investigations, though meanwhile the accumulation of data continued. 

Dall, during the Russian regime, had made a geologic reconnaissance of the lower 

Yukon Valley and of a part of the Norton Bay region, and after the transfer spent 

a number of years in seaboard explorations under the auspices of the Coast Survey. 

Blake, too, contributed notes on the coastal geology, and later Russell and Hayes 

made inland journeys, while the Canadians, Dawson and McConnell, made important 

contributions to the g'eology of the adjacent regions. The Alaskan glaciers were 

studied by Muir, Russell, Wright, Reid, and others, in whose publications are 

found occasional references to bed-rock features.

At best these investigations were little more than the observation of isolated 

facts which, though not without value, in only rare instances offered a sufficient 

groundwork for general conclusions.

An appropriation by Congress for the investigation of the mineral resources of 

Alaska enabled the Geological Survey in 1895 to dispatch its first regular party to 

the Pacific coastal belt, and in the following year a second was sent into the interior. 

These were the precursors of the many to follow. Systematic surveys were begun 

in 1808, and in the last seven years twenty-odd expeditions have investigated 

this field, some visiting its remotest parts. Explorations have been the objects of 

most of these journeys, for daring many of them even the geologic reconnaissance 

mapping was forced to give way to random notes on such phenomena as were 

encountered in the direct route of travel. Alaskan exploration demands of the 

geologist only too often that he abandon for a time all research and give himself 

entirely to overcoming the physical obstacles that beset his progress. Such 

interruptions may be of hours, of days, or even weeks; may mean a long, weary 

portage between watercourses, rafting a turbulent glacial river, building a causeway 

through a swamp, chopping a trail through an interminable forest, or scudding 

before a storm on an exposed sea coast, but they always leave a hiatus in the

"Grewingk, C., Beitriige zur Kentniss dor orographischeii und geognostischen Beschaffenheit dor Nord-west Kiiste 

Amcrikas, mit den anliejH'ndcn Inseln (\vith geologic and other maps). St. Petersburg, 1850.
202 GEOGRAPHY AND GEOLOGY OF ALASKA.

geologic notes that may prove fatal to correct generalizations. A personal 

knowledge of the conditions of work alone can show why the results have often been 

so meager, and at what cost of toil and exposure these investigations have been 

made.

Nor do the physical conditions of this field permit of a rapid determination of 

the bed-rock geology, for here are no such opportunities for geologic observation as 

are found in the plateau region of the western United States, with its deep canyons 

and bare rocks. Alaska is mantled by a heavy growth of moss and other vegetation, 

and the traveler may journey for days with hardly a clue to the character of the bed 

rock except the gravels in the stream beds, and though in the mountain ranges 

exposures are usually better, here again the structure is often so intricate as to 

defy solution during a rapid journey. Man}7 of the problems will require the most 

detailed and painstaking study, and few can be solved by rapid reconnaissance work, 

as have been many of those of the western cordillera of the United States.

If, then, the researches in the geology of this field of the past decade have 

as yet left no landmarks like the exhaustive monographs which resulted from the 

explorations of the trans-Mississippian region, there is reason for it in the difficulties 

of the field. Furthermore, the immediate results aimed at, besides exploration, 

have been the development of the mineral resources, and in many instances the 

purely geologic studies have been made entirely subordinate to this object. The 

progress on the general structural and stratigraphic problems may appear to 

have been very slow to those unfamiliar with the conditions and purposes of the 

survey; if, however, it is borne in mind that ten years ago practically nothingwas known of the geology of this area of nearly 600,000 square miles, except 

along parts of the coast, it will be manifest that the results achieved are 

commensurate with the time that has been devoted to them.

The terranes of Alaska range in age from crystalline schists, probably 

Archean, to recent deposits of unconsolidated material. The stratigraphic position 

and distribution of some horizons have, been fairly well established in the areas 

which have been surveyed, but there are. man}' more beds of which little or 

nothing is known. Igneous rocks are widely distributed both horizontally and 

vertically, and occur in many varieties, both as intrusives and extrusives. The 

sedimentary arid igneous rocks have passed through many recurrent epochs of 

disturbances, some of which have brought about flexures and dislocations, while 

others were of the nature of broad orogenic movements, which have uplifted or 

depressed large areas in their relation to sea level, with little or no plications. 

The epirogenic movements or periods of faulting and folding have induced the 

complex relations of the rock strata or masses of various parts of the province; 

but these deformations, even where they have affected considerable areas, were 

usually intensified along certain zones which have a general parallelism to the 

dominant physical features. Though something is known of the dynamic history 

of the region, most of its problems remain to be solved.
U.S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO.45 PL.XX

18O° n5° 17O° 165° 160° 155° 15O° M5° 14O° 135° 13O° 125& 12O° 115° 11O° 1O5° 1OO° 95°

150° I,on§itiide M5° "West from 14O° Greenwicli 135'

LEGEND

Quaternary

GEOLOGIC SKETCH MAP OF NORTHWESTERN 

NORTH AMERICA

Compiled from publications 

of U.S.Geological Survey and 

Geological Survey of Canada 

by Alfred H. Brooks

ipo p____loo Scale2OO 3OO 4-OQ

1904

SpO 6QO "TOO miles

Volcanics
GEOLOGY. 208 

CORRELATION WITH WESTKIIX UNITED STATES AND CANADA.

Any connection that can be established between the stratigraphy of Alaska 

and that of better-known regions will lead to a better understanding of the 

geology. Correlations between localities separated by hundreds if not thousands 

of miles must be of a very general character, unless the intervening area has 

becu carefully mapped, or paleontologic evidence furnishes definite proof. Of the 

latter there is in this case little, for up to the present time but few collections 

of fossils have been made, and most of the age determinations have been based 

on very fragmentary material.' The interpretation of Alaskan stratigraphy has 

been aided by the work of the Canadian Geological Survey, which for over a 

quarter of a century has been actively mapping western Canada, so that now the 

general sequence and distribution of the larger divisions of the time scale are 

fairly well established. The results, in a large measure to be credited to Dr. 

George M. Dawson and Mr. K. G. McConnell, have been embodied in a geologic 

map" of western Canada, on which is shown the distribution of the larger 

divisions of the stratigraphic column known as " systems/' and which has been used 

as a basis for the accompanying geological sketch map (PI. XX), which is 

intended to express, in a general way; the relation of the geology of Alaska to 

that of western Canada and the United States.

As the physiographic provinces of Alaska are continuations of those of the 

western United States and Canada, and as they are in a measure but an expression 

of the bed-rock geology, it would be inferred that the same general horizons which 

form the cordillera of western United States and Canada extend into Alaska. Such 

has been found to be the case.

The trend of the structure is northwest, parallel to shore line and the mountain 

ranges. It is thus northwest-southeast iri southeastern Alaska, and then southwestnortheast. The parallelism of the structural features of the Paleozoic and older 

rocks makes it evident that this marked change of direction of the axes has 

dominated the deformation of this province since very early geologic time.

Dawson* has stated that there iy a marked continuity and lithologic uniformity 

along the strike of the various terraues in this cordilleran belt, and as to a certain 

extent this holds true in Alaska, it is possible to delineate on the map some of the 

larger geologic features throughout the entire province.

Several areas of gneissoid rocks, including gneisses, mica-schists, and igneous 

intrusive, with probably some altered sediments, are provisionally referred to the 

Archean, though their pre-Cambrian age is open to question.

The sedimentary rocks on this map (PI. XX) have been divided into four 

groups, in the oldest of which are placed the beds which have been more or less 

metamorphosed, and whicn are probably, for the most part, Paleozoic, though it is 

known to include some Triassic. All the rocks of this division, which embraces a 

number of unconformable series, were closely folded and considerably altered 

before the deposition of the second group which embraces the higher terranes of the 

Mcsoxoic and are chiefly Cretaceous, though it includes some Jurassic. The beds of

o Geological map of the Dominion of Canada, Western Sheet, No. 783 Geol. Survey Canada.

* Geological record of the Rocky Mountain region Canada: Hull. Gcol. Hoc. America, vol. 12, p. 80.

17211 No. 45 06 14
U.S.GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 45 PL.XXI

GEOLOGIC RECONNAISSANCE 

MAP OF ALASKA

I-»IT TT»T~I T~*A7" A T Tnnir»T~\ T i ir>i > t
204 GEOGBAPHY AND GEOLOGY OP ALASKA.

this second group have also been subjected to stresses and are closely folded, but 

not to anything like the extent of the underlying metamorphic terranes. Beds of 

Tertiary age, probably chiefly Eocene, form the third of these large subdivisions 

and rest unconformably on the two older series. These also have been deformed, 

but in most cases'to a. much less extent than the Mesozoic. The Pleistocene 

unconsolidated gravels, sands, and silts are the highest of the groups and also the 

best defined; but as they wore not indicated on the Canadian map their occurrences 

in this part of the province is necessarily omitted on the accompanying sketch 

(PI. XX).

The igneous rocks fall into two groups, the intrusives and extrusives. The 

extrusives are especially abundant in the southern part of the field and decrease 

to the north, though evidences of recent volcanic activity are far from being 

 absent in Alaska. The igneous complex of the Coast Eange is the only extensive 

area of intrusive rocks in the field. Intrusive rocks are, however, very common 

throughout the province, especially in the areas of metamorphic torranes.

In general the rocks are distributed as follows (see map, PI. XX): A bolt of 

metamorphic sediments, chiefly Paleozoic, but .with some Triassic, skirts the shore 

of the Pacific and is the bed rock of the islands of British Columbia and of southeastern Alaska, as well as part of the mainland. This is bounded on the east l>y 

the great zone of Coast Range intrusives.. East of the Coast Range is a second 

belt of metamorphic torranes, probably chiefly Paleozoic, of irregular form, about 

300 miles in width and stretching from Washington to the northwest into Alaska, 

a distance'" of 1,000 miles, and occupying in a general way the intermontane belt 

between the Rocky Mountains on the east and the Pacific Mountains on the west. 

This zone is interrupted by a number of elongated gneissic areas (Archean?), which 

have a roughly linear arrangement along a northwest-southeast axis, and by irregular 

areas of intrusives, of Mesozoic sediments, and of Tertiary lavas.

A belt of Mesozoic sediments forms the eastern boundary of the metamorphic 

rocks south of the sixtieth parallel of latitude. These include not only the 

undisturbed Mesozoic beds which underlie the Tertiary of the Great Plains region 

to the east, but also some older terranes of this system, which, infolded with 

Paleozoic sediments, make up the Rocky Mountains.

Tracing these groups northward, it is found that' the western belt of 

metamorphics skirts the coast line, and, 1 following the bend at Prince William 

Sound, is continued in the Kenai Peninsula. The Coast Range-complex is extended 

to the north by a series of intrusivos along the axis of the Alaska Range. 

The interior belt of metamorphic sediments broadens into a fan-shaped area in 

Alaska, but is interrupted near Bering Sea by extensive areas of Mesozoic rocks. 

The eastern bolt of Mesozoic and Tertiary rocks of British Columbia finds its 

counterpart in the rocks of similar age in the Arctic slope region.

GEOLOGIC RECONNAISSANCE MAP.

Though much of Alaska is still unsurveyed, the general distribution of some 

of the larger subdivisions of the time scale is known sufficiently well to be 

indicated on the accompanying map (PI. XXI), which is a graphic summary of
GEOLOGIC RECONNAISSANCE MAP. 205

what has been learned of the geology. While the blanks in the map represent 

unsurveyed areas, it must not be supposed that the colored portions represent 

results of equal value. Areas like the Seward Peninsula and the Copper River 

basin have been surveyed in considerable detail; others, like the Kuskokwim and 

Tanana valleys, have been covered by only the most hurried reconnaissance 

work. In some mountain regions the geologic coloring has been extended to 

cover areas almost entirely unexplored, but only where topographic continuity 

between geologic sections pointed to probable geologic continuity. For example, 

the geology of the central part of the Alaska Range is inferred from the three 

cross sections at the Skwentna, the Cantwell, and Delta river valleys. The 

relative value of the geologic coloring in different parts of the map will be 

further brought out in the discussion.

Ten subdivisions are indicated on the map (PI. XXI); seven are sodimentarj-, 

two igneous, and one metamorphic. The so-called Avchean is made up of gneisses 

and crystalline schists and possibly some sediments which are in part undoubtedly 

basal, but very likely are in part deformed igneous rocks of a later date. A succession of more or less highly altered sediments, embracing many different formations and believed to be largely Paleozoic, but also known to include some lower 

Mesoxoic terranes, occupies the largest areas in the province. The areas of Silurian 

are small, because it is onlv where fossils have been found that they could be 

differentiated from the other metamorphic terranes. Lack of detailed knowledge 

makes it necessary on the map to throw the Devonian and Carboniferous into 

one group, while over much the larger part of the rield it has been found 

impossible to make any subdivisions in the Paleozoic.

Though all the subdivisions of the Mesozoic have been recognized in Alaska, 

the data are yet too fragmentary to permit of mapping them separately, and only 

two groups are recognized. The one embraces the Triassic and Jurassic, as well as 

the undifferentiated Mesozoic, and the second the Cretaceous. The reason for 

this apparently arbitrary division lies in the fact that the distribution of the 

Cretaceous is better known because it is usuall}7 fossiliferous. The Mesozoic 

indicated in the Alaska Peninsula probably includes some Tertiary beds.

The Tertiary, undifferentiated on the accompanying map, is almost entirely 

Eocene, for Miocene and Pliocene beds have been found in considerable areas only 

on the north coast and along the southwest slope of the St. Elias Range.

The Pleistocene coloring has been extended to only the larger areas and has 

perforce been made to include the recent alluvium. Most of the rivers, except those 

that traverse the Coast Range, are bordered by Pleistocene silts and gravels.

Of the intrusives the scale of the map permitted the representation of only the 

larger stocks, and even those have been omitted in the Archean areas, where the 

gneisses and igneous rocks are not always easily differentiated. The distribution 

of the Recent and Tertiary volcanics is shown throughout the regions surveyed, 

but many smaller areas were omitted because of the scale of the map.

The general facts of the geology, as already indicated, are a belt of metamorphosed sediments, chiefly Paleozoic, skirting the Pacific coast, bounded on the north 

and west first by intrusives, and then beyond the great bend by Mesozoic rocks. 

Inland of these lies a second belt of altered sediments, in part Paleozoic, and
206 GEOGRAPHY AND GEOLOGY OF ALASKA.

these give way north of the Rockies to Mesozoic and Tertiary bods. The intermontane zone of Paleozoics is interrupted by Pleistocene deposits and by a broad belt of 

Cretaceous rocks, which stretches northeast from Bering Sea to the l)asc of the 

Mockies. Volcanic rooks are widely distributed, and in the Alaska Peninsula, 

Mount Wrangell region, and in the Bering Sea littoral cover considerable areas.

The correlation table (opposite) is based on a study of the literature as well 

as on a personal knowledge of much of the field. Though many of these correlations are by those who did the neld work, the writer has not hesitated to express 

in the table his own interpretations of the succession, even though they are at 

variance with those of the original investigators.

It is not to be inferred that because two formations appear as equivalents in 

the table they are considered exactly synchronous, for in few instances have the 

stratigraphic studies been made in sufficient detail to permit the determination of 

exact equivalencies between the terranes of different regions. Furthermore, the 

stratigraphic units of Alaska maps and reports vary greatly in definition, and range 

in thickness from o() feet to many thousands of feet. While in some cases a name 

may designate a well-defined horizon, whose position is established by stratigraphic 

and paleontologic evidence, in others, a heterogeneous aggregate of strata, of whose 

thickness, stratigraphic relations, distribution, and age almost nothing is known, 

has been grouped together as a "series." The Carboniferous rocks in the upper 

Copper River and in northern Alaska are cases in point. In the first district the 

Carboniferous terranew have been divided into two distinct formations, the "Suslota" (Lower Carboniferous) and "Mankomen" (Permian), on paloontologic and 

stratigraphic evidence; in the second, a great complex of schists, conglomerates, etc., 

has been assembled under the name "Fickett series," and assigned to the Carboniferous on very scant evidence. Though all of these formations appear as Carboniferous in the table the definite correlation between them is yet to be established.

Tt has not l)een possible to include all of the formations mentioned in the 

literature, for Alaskan stratigraphy is rather overburdened with names, in view of 

the lack of detail in the field studies. There are now upward of one hundred 

different names which have been given to various stratigraphic subdivisions of 

Alaska, and probably half of these have been applied to very ill-defined units. 

Some of these have already been relegated to oblivion by the workers in this field, 

and many more will follow, but it is exceedingly difScult to eliminate these from 

the literature. Effort has been made to include in the table ohicfly those which 

promise to become fixed in the nomenclature, but for the sake of clearness others 

are inserted which will probably not be retained, in the text practically all of 

the formation names which have appeared in print will be discussed. The writer 

feels less hesitancy in making this criticism of the redundancy of stratigraphic 

nomenclature because he is himself responsible for part of it.

Dawson's generalized section of British Columbia and Yukon Territory forms 

the first column of the table, and as it is based on closer field studies than most
CORRELATIONS. 207

of the sections for Alaska, it may be used as a general standard of comparison. 

The other sections are arranged, us far as possible, geographically from south to 

north.

The second column, which indicates the succession in southeastern Alaska, 

is largely the writer's own work, but he has received helpful suggestions from 

Spencer, whose recent geologic work in the Juiieau district is not yet published. 

Use has also been made of the unpublished notes of F. E. and C. W. Wright.

The work of Schrader, Spencer, and Mendenhall has made the geolog}7 of the 

southern Copper River basin fairly well known, though the relation of this area 

to the Chugach Mountains and Prince William Sound regions is still undetermined. 

Their results are embodied in the third column and indicate the succession in the 

Chitina Valley and the south slope of the W range 11 Mountains.

Mendenhall and Schrader have mapped the northern and western slope of the 

Wrangell Mountains, together with an area stretching northward to the Tanana, 

and the succession determined by them is given in the fourth column. The writer 

has recqnnoitered the adjacent region to the north and east, where there still remain 

manv unsolved important stratigraphic problems.

The fifth column indicates the succession in the Alaska Range, near the 

Skwentna-Kuskokwim divide, as determined by Spurr and the writer. In this 

district, though the horizons seem well defined, both lithologically and paleontologically, lack of detailed mapping has rendered it impossible to subdivide the 

Paleozoic on the west side of the range, though Ordovician and Devonian fossils 

have been found.

The succession in the middle and lower Yukon region is probably better 

known than any other part of the field, thanks largely to Collier's detailed studies, 

though others have made important contributions. The results are presented in 

the sixth column of the table. Though the sequence of the strata is fairly well 

known, there has been no areal mapping, and as the horizontal extent of the 

section is probably a thousand miles, errors have probably crept in, because of the 

variation of individual strata, which in the absence of paleontologic evidence might 

lead to faulty correlations.

Schrader's reconnaissance across the Rocky Mountains in northern Alaska 

furnished a general key to the stratigraphic succession, but so rapid was the journey 

and so beset by difficulties that the sequence can hardly be regarded as definitely 

established. The sixth column of the table is largely based on this work of 

Schrader's, but use has also been made of his previous investigation in the 

Chandlar and Koyukuk basins and of Mendenhall's reconnaissance from the Yukon 

to Kotzebue Sound.

The reconnaissance mapping of the entire Seward Peninsula was completed at 

the close of the field season of 1903, and the general succession, as indicated in the 

table, is probably correct. The geology is, however, complex, and further studies 

will be needed before the details and structure of the metamorphic rocks can be 

learned. The sequence as presented does not differ greatly from that determined 

by the writer in 1900, but Collier's results of later years have been incorporated.
208 GEOGRAPHY AND GKOLOGY OF ALASKA.

STRATIGKAPII1C SUCCESSION".

OUTLINE.

The general sequence of strata is presented in the table facing p. 206, and the 

distribution of some of the large subdivisions of the geologic section is shown on 

the geologic map (PI. XXI). The geologic succession in different districts will 

now be discussed in some detail, and the facts presented on which the correlations 

are based. It is believed that this section of the paper will be made clearer by 

divorcing front it all consideration of structure, and avoiding as far as possible 

references to the dynamic history of the province. These subjects will therefore 

be taken up later.

A brief survey of the geologic sequence may serve as outline for the more 

detailed discussion to follow. The gneisses and crystalline schists, provisionally 

referred to the Archean, are regarded as the basal member of the stratigraphic 

column. Those are succeeded by a great complex of metamorphic sediments, 

intruded by many igneous rocks whose age and stratigraphic relations are often 

undetermined. Though they have been subdivided into many formations many of 

them are very ill denned, and much more detailed evidence will be required before 

the succession is definitely established. Ordoviciau and Silurian fossils have been 

found in some of the lower members of this great complex, and Devonian fossils in 

some of the higher. In the Yukon basin there seems to be an unconformity near the 

base of the Devonian, below which the rocks are much more highly metamorphosed. 

These older and more highly crystalline sediments are likely to prove of Silurian. 

Ordovician, or Cambrian, or possibly pre-Cambrian age. The metamorphosed 

elastics of southeastern Alaska include Devonian, Carboniferous, and possibly 

Triassic beds, but it has not yet been possible to subdivide the metamorphic series. 

Elsewhere in the province recognizable Devonian and Carboniferous terranes also 

find place in the stratigraphic succession.

The Triassic and Jurassic have thus far been recognized only in the Copper 

River basin and in southwestern Alaska. The lower Cretaceous is more widely 

distributed, and includes the youngest beds known to have suffered any considerable 

alteration. A marked unconformity is believed to separate the lower and upper 

Cretaceous horizons. The upper Cretaceous is well represented in the lower 

Yukon basin and north of the Rockies, and has also been recentlj- found by Wright 

at Kuiu Island.

Of the Tertiary horizons the Eocene coal-bearing- beds are the only ones which 

have been found widely distributed, and these occupy no considerable areas. The 

Miocene and Pliocene seem to have a relatively small development. The Pleistocene 

is repiesented throughout the province by gravels, sands, and silts, and in the 

regions which have been occupied by ice by various forms of glacial deposits.

PRE-PALEOZOIC. 

AKCHKAN.

It is a long-established practice that a complex of crystalline schists should bo 

assigned to the Archean, unless there is proof that it is younger. More detailed
ARCHEAN ROCKS. 209

studies of the so-called Aroheaii often lead to quite different conclusions, and in 

Alaska the areas assigned to the "Archean" and "Basal granite" are being reduced 

in size, if not entirely eliminated. For instance, in the Yukon-Tanana region 

Prindle's" recent studies have shown that if the Arcnean rocks are present at all 

they are in much smaller areas than indicated on some of the earlier maps. 

McConnell, 6 too, has shown that some of the granites of the same general region 

which have been called basal are in fact intrusive in the sedimentary rocks. With 

all these eliminations there still seems to remain gneisses, gneissoid granites, and 

crystalline schists, which probably form a basal complex and will provisionally be 

assigned to the Archean.

A number of belts of gneissoid rocks of lenticular outline stretch from southern 

British Columbia e into Alaska (PI. XX), with a roughly linear arrangement, and 

with these Dawson grouped his "Shuswap series," composed not only of gneisses 

and crystalline schists, but also of crystalline limestones and quartzites. Dawson 

pointed out its lithologic and structural similarity to the Greenville d series of eastern 

Canada, and provisionally assigned them to the Archean. It appears that such age 

criteria of crystalline schists can have no great value, though the conclusion that 

they are a part of a basal complex of western Canada is supported by their general 

structural relations and lithologic character.

The northernmost of these gneissoid areas crosses into Alaska between the 

Tanana and the Yukon and is well exposed along the lower White River, where it 

comprises a complex'' of gneisses and mica-schists, with igneous intrusives, both 

massive and schistose, and both basic and acid. The belt seems to stretch 100 miles 

to the west of the White River, where it probably pitches under the younger sediments. The writer is prepared to believe that sediments may be included in these 

areas of gneiss and that the results of detailed studies may lead to the assignment 

of the entire series to a higher horizon than is here given them.

Another belt of crystalline schists lies to the west in the extension of the axis 

of the White River gneissic area, and the basal character of these is attested by 

better, though not by any means conclusive, evidence. The writer in the course of an 

exploration--'' crossed this belt of gneisses south of the Tanana and near the head'of 

the Cantwell, but there was no opportunity to examine the rocks in detail. The 

rocks are typified by a coarse augen-gneiss similar to that of the gneissic complex of 

the upper Tanana. This augen-gneiss appears to grade upward into a feldspathic 

conglomerate which seems to form the basal member of the metamorphic sediments. 

If such are the facts, these gneisses would appear to be a basal complex. This 

would also suggest that the other gneissic areas lying to the southeast are Archean, 

as they all appear to belong to the same belt.

a Prindle, L. M., The FortymHe, Birch Creek, and Fairbanks gold placers: Bull. U. S. Geol. Survey No. 251.

6 McConnell, R. G., The so-called basal granite of the Yukon: Am. Geol., vol. 30, 1902, pp. 55-62.

"Dawson, George M., Geological record of the Rocky Mountain region in Canada: Bull. Geol. Soc. America, vol. V2, 

1901, pp, 62-64; Geological Map Dominion of Canada (Western Sheet No. 783), Geological Survey of Canada.

f! Dawson, G. M., ibid., p. 63.

e Brooks, A. II., Reconnaissance of the White and Tanana river basins: Twentieth Ann. Rept. I". S. Geol. Survey, 

pt. 7, 1900, pp. 400-466,

/Report is in preparation. An abstract entitled Reconnaissance in the Mt. McKinley region, Alaska," was 

published in Science, new ser., vol. 16, 1902, pp. 985-98S.
210 GEOGRAPHY AND GEOLOGY OP ALASKA.

Schrader a observed a few outcrops of gneissoid granites and mica-schists in 

the lower Chandlar Valley north of the Yukon and assigned them to the Archean. 

As the evidence presented h}T him makes it almost equally probable that these may 

be sheared granitic rocks, intrusive in his Lake schists (sedimentary), they are not 

differentiated from the metamorphosed sediments on the geologic map (PI. XXI). 

In this connection it is worthy of note that the older sedimentary terrancs of the 

region sometimes contain crystalline schists and sheared eruptives, which render 

lithologic evidence of Archean age of relatively little value.

Gneisses are reported by Spun1 * in the Kuiu Mountains east of the lower 

Yukon, and by Collier west of the Yukon, near the mouth of the Melozi River, but 

their Archean age remains to be proved.

The only other rocks which have been referred to as basal granite are near the 

western margin of the upper part of the Alaska Peninsula. These, described by 

Spurr, c were assigned by him to the pre-Jurassic, but had previously been called 

Archean. They appear to be an igneous complex of early Mesozoic age (PI. XXI).

PALEOZOIC.

GENERAL STATEMENT.

The base of the sedimentary succession is not yet known, but it must be 

sought in the belts of metamorphic elastics, where few structural and age determinations have been made. One such zone (see PL XXI) stretches through 

the Alexander Archipelago and probably continues northward into the St. Elias 

Range. A second forms a broad belt in the intermontane region and is continuously traceable from the international boundary north and west to Bering 

Strait except where mantled by younger beds. It is a complex of metamorphic 

sediments and eruptives, including rocks of very diverse lithologic types, and 

ranges in age from probably Cambrian, possibly pre-Cambrian, to Devonian, though 

it is chiefly pre-Devonian. Some lower Mesozoic terranes may also be included with 

these metamorphic sediments, as outlined on the map, for what appears to be 

the same series in the Queen Charlotte Islands to the south includes both Triassic 

and Carboniferous beds, and as both these series have been subjected to about the 

same degree of metamorphism they can be separated only by detailed mapping, 

which has not yet been done.

As little has yet been accomplished toward differentiating and mapping this 

complex series, it is indicated, for the most part, as a cartographic unit (PL 

XXI). In northern Alaska, where the horizons are somewhat less altered, there 

is some paleontologic^ evidence of Devonian, Carboniferous, and Silurian terranes, 

and Devonian and Carboniferous fossils have also been found on the Yukon;" 

Lower Silurian organic remains occur in the Seward Peninsula,-'" and Ordovician?

a Schrader, F. C., A reconnaissance along Chandlar and Koyukuk rivers: Twenty-first Ann. Kept. U. S. Geol. Survey, 

pt. 2, 1900, pp. 471-472.

<>Spurr, J. E., Reconnaissance in southwestern Alaska: Twentieth Ann. Kept. U.S.Geol. Survey, pt. 7, 1900, pp. 234-235.

elbid., pp. 234-235.

'^Schrader, F. C., Reconnaissance in northern Alaska: Prof. Paper Q. S. Geol. Survey No. 20, 1904, pp. 55-71.

eCollier, A, J., The coal resources of the Yukon: Bull. U. S. Geol. Survey No. 218, 1903, pp. 16 and 17.

/Collier, A. J., A reconnaissance of the northwestern portion of the Seward Peninsula: Prof. Paper U. S. Geol.Survey 

No. 2, 1902, pp. 20-21.

» Brooks, A. H., An exploration in the Mt. McKinley region (in preparation).
PALEOZOIC BOCKS. 211

and Devonian forms have been found along the western front of the Alaska 

Range. A few Silurian/' Devonian, and Carboniferous forms have been collected 

from the metamorphic rocks of southeastern Alaska.

These facts indicate that the metamorphic complex, which must have a 

thickness measured by thousands if not tens of thousands of feet, is probably 

chiefly Paleozoic. Over much of the province the series is so complex that 

reconnaissance surveys have yielded but scant results, but in some districts the 

general succession is fairly well known and forms the basis of the correlations 

which have already been epitomized in the table facing page 206.

The table does not reveal any close analogy between the Paleozoic succession 

of western Canada and of any part of Alaska, for the inetamorphism seems to 

have been much greater in Alaska than in Canada, or, in other words, seems to 

increase to the northwest. Dawson 6 reports 40,000 feet of Cambrian strata in 

Canada. The equivalents of these rocks are probably present in Alaska, but they 

lie in the part of the metamorphic series which has not yet yielded fossil remains. 

All the post-Cambrian systems of western Canada have been found in some 

parts of Alaska.

Though on the map (PI. XXI) the Paleozoic areas are largely undifferentiated, for reasons already given, all that is known of the succession will here be 

summarized. The rocks believed to be the oldest sediments, even though their 

stratigraphic position is very much in doubt, and the Silurian and Ordovician 

terranes will be discussed under the heading "Lower Paleozoic." The Devonian 

and Carboniferous will receive separate consideration.

LOWER PALEOZOIC.

The discussion of the presence or absence of Cambrian and Silurian terranes 

must be deferred until the succession of the older sedimentaries in various parts 

of the province has been presented.

The metamorphic rocks of southeastern Alaska include what seems to be 

a more or less well-defined belt'- of white crystalline limestone and phyllitcs 

stretching through the westernmost islands of the Alexander Archipelago to 

Glacier Bay, where they have yielded a few Silurian fossils. d Silurian fossils 

have also been found at Freshwater Bay on Chichagof Island. The name 

"WT ales series" has been given to some limestones and phyllites on Prince of 

Whales Island that appear to lie in the southern extension of this belt. Though 

metamorphic rocks appear to be abundant in this district, this is the only terranc 

which has been assigned to the lower Paleozoic. The strike of these rocks to 

the northwest would carry them into the unexplored'St. Elias Range, where the 

only clues to the geology are a few random notes/ For nearly 200 miles the

aBrooks, A. H., A reconnaissance of the Ketchikan mining district: Prof. Paper U. S. Geol. Survey No. 1, 1902, pp. 19, 

21, and 43. Also unpublished notes of F. K. and 0. W. Wright.

t>Geological record of the Rocky Mountain region of Canada: Bull. Geol. Soc. Am., vol. 12, 1901, p. 62.

( Brooks, A. H., op. cit.,pp. 19-24 and 41-45.

rfThese organic remains were at first assigned to the Carboniferous, but were subsequently proved to be of Silurian 

age. Op. cit. p. 19-20. It is very unfortunate that the assignment of this limestone to the Carboniferous should again 

have appeared in print (Harriman Alaska Expedition, vol. 4, p. 20) two years after the correction had been made.

( Brooks, A. H., A reconnaissance from Pyramid Harbor to Eagle City, Alaska: Twenty-first Ann. Kept. U, S. Geol. 

Survey, pt. 7, 1900, pp. 356-373.
212 GEOGRAPHY AXD GEOLOGY OF ALASKA.

region where these terraries might be expected to outcrop is entirely unknown, 

but near Yakutat Bay Russell" found a metamorphie terrane of unknown age. 

called by him the "St. Elias schists," which may represent the same horizon. 

One hundred miles farther west in the same strike are crystalline limestones and 

schists called by Schrader the "Klutina" 6 series and assigned to the pre-Devonian, 

because of their lithologic similarity to the Fortymile series, which occurs-in an 

entirely different province, 300 miles to the north. Schrader's "Valdez series," 

of this same district, will be discussed with the Mesozoic terranes.

Mendenhall e mapped a small area of highly altered schistose rocks on the 

southern flank of the Wrangell Mountains, under the name "Dadina schists," and 

provisionally assigned them to the Silurian. Little is known of their stratigraphic 

relations, except that they are probably older than the Permian, and in many 

ways resemble the Klutina rocks.

The name "Tanana schists," first applied by the writer tl to some metamorphosed, fine-grained, argillaceous, and calcareous rocks of the upper Tanana 

Valley, was extended by Mendenhall f to more highly altered sediments in the 

Alaska Range, which seem to be an extension of the rocks of the type locality. 

Mendenhall has again applied this name to the metamorphie schists of the Alaska 

liange in his later report already cited. In the type locality the Tanana schists 

are known to be older than the Carboniferous, and are probably older than the 

Devonian. On the Copper River they are overlain unconformably by beds which 

are probably Devonian, and it is likely that the Tanana schists are lower Paleozoic 

or pre-Cambrian. There is, however, further evidence, for the schists of the 

Alaska Range have been identified again 100 miles to the southwest, where they 

are well exposed in the gorge of the Cantwell, and appear to extend to the 

southwest with decreasing metamorphism, and to merge with the closely folded 

cherts and slates which carry Ordovician fossils and limestones and which are 

traceable along the western front of the Alaska Range.-'' This latter group of 

sediments includes a great thickness of Paleozoic terranes, varying in age from 

at least the Ordovician to the Devonian. The writer, unable to differentiate 

these, mapped them as a unit, as Spurr had previously done under the name 

Terra Gotta series. 91 Spun1 , who named the series and provisional!}' assigned it 

to the Jurassic, recognized its unconformable relation to the overlying beds 

(Tordrillo series), which he had assigned to the Cretaceous, but which have since 

been proved to be Jurassic (p. 231). This evidence points to the conclusion that the 

Terra Cotta may in a general way be synchronous with the Tanana and that both 

belong to the lower Paleozoic.

a Russell, I. C., Expedition to Mount St. Elias: Nat. G-cog-. Mag., vol. 3, 1891, p. 173-174.

& Schrader, F. C., A reconnaissance of a part of Prince William Sound and the Copper River district, in 1898. 

Twentieth Ann. Kept. U. S. Geol. Survey, pt. 7, 1900, pp. 408-410. Schrader, F. C., and Spencer, A. C., Geology and 

mineral resources of a portion of the Copper River region, U. S. Geol. Survey, 1901, pp. 34-37.

'. Mendenhall, W. C., The geology of tlie central Copper River region: Prof. Paper II. S. Geol. Survey No. 41. 1905, 

pp. 27-30.

<i Brooks, A. H., A reconnaissance in the White and Tnnana river basins: Twentieth Ann. Rept. U. S. Geol. Survey 

pt. 7, 1900, pp. 468-470.

e Mendenhall, W. C., A reconnaissance from Resurrection Bay to the Tanana River: Twentieth Ann. Rept. U. S. Geol. 

Survey, pt. 7, 1900, pp. 313-314.

/Brooks, A. II., An exploration in the Mount McKinley region (in preparation).

a Spurr, J. E., A reconnaissance in southwestern Alaska: Twentieth Ann. Kept. [". S. Geol. Survey, pt. 7, 1900, pji. 

156-157.
LOWER PALEOZOIC BOCKS. 218

The oldest sediments of the Yukon-Tanana region include a great thickness of 

closely folded siliceous schists, phyllites, and quartzites, associated with crystalline 

limestones. The basal member of this series is believed to be an arkose conglomerate 

(see p. 209), and to have been derived from the erosion of the gneisses, which would 

indicate an unconformity at the base of the sediments. According to Spurr," the 

conglomerate is succeeded by Birch Creek schists (Birch (Jrcek series), typified by 

highly altered arenaceous sediments, often carrying graphite. Spurr's estimate of 

the thickness as 25,000 feet is probably much too great, for Prindle's* more detailed 

studies in the same field have shown that the folding is so complex as to almost defy 

accurate measurements of thickness.

The arenaceous sediments merge gradually upward into calcareous rocks and 

finally into the crystalline limestones interbedded with quartzites, which Spurr" 

called "Fortymile series." This series is typically made up of marbles and quartzites. with some hornblende and garnetiferous and sometimes graphitic schists. 

Prindle and Hess in 1904 found fossils of either Silurian or Devonian age in a white 

crystalline limestone in the headwater region of Birch Creek and Tolovana River. 

Both the Birch Greek schists and the Fortymile series contain abundant intrusives 

and are cut by many quartz veins, some of which are metalliferous and form the 

source of the placer gold. These two formations arc unconf ormably overlain by the 

Rampart series (Devonian), and are therefore of lower Paleozoic or pre Cambrian age.

McConneH's** determinations of the stratigraphy of the Klondike region, made 

in considerable detail, are briefly summarized in the following table:

j/ of (Ae JTZond/te

Syntem. Formation.

Stratified and foliated rockw, mogtly Paleoznic..

Moose Hide group...

Llthologlc character.

'Green igneous rocks, both

massive and schistose. 

fMicaceous and feldspathic

Klondike series... _.!J schists, probably altered 

^ cruptivcs.

JGraphite-schists, some limeHunker series....... ;j stones, dolomites, and greeu

! [ schists. 

Slates aud quartz-schists, passIndian River series.. ing into mica-schists, with 

some limestone.

While there is not the close correspondence which might be expected between 

this sequence and that determined by Spurr in the adjacent regions to the west, yet 

there is some similarity. McConnell's basal rocks, the Indian River series, similar

n3purr, J. E., The geology of the Yukon gold district: Eighteenth Ann. Rept. U. S. Gool. Survey, pt. S, 1900, pp. 140-145. 

& Prindle, L. M., Gold placers of the Fortymile, Birch Creek, and Falrbankw regions: Bull. U. S. Geol. Surrey Nb.251. 

rSpurr, J. E., op. clt., pp. 145-654.

ell. R. G., The Klondike region: Aim. Rept. Menl. Survey Canada, vol. 13, now series, 1S99, pp. 18A-20A.
214 GEOGRAPHY AND GEOLOGY OF ALASKA.

to the Birch Creek schists, are overlain by the Hunker series, not unlike the 

Fortytnile series. No equivalent of the Klondike series has been recognized to 

the west, and though the highest of McConnell's metamorphic rocks are of igneous 

origin, they are not very similar to the Rampart series (Devonian).

Some white crystalline limestones, with phyllites, seem to overlie the gneisses 

on the lower White River. They were called the "Nasina s series," and 

provisionally correlated with the Fortymile rocks. McConnell* has adopted the 

name "Nasina series," and in a personal letter states that he has traced it far to 

the south and inclines to the belief that it is the equivalent of the sediments included 

by Dawson in his Shuswap series.

Since the above was written, Prindle and Hess have spent a field season in the 

Yukon-Tanana region. Their results have riot yet been digested, but the following 

table presents in concise form their provisional conclusions:

Stratigraphy of the Yukon-Tanana region.

System. Formation. Relation.

Pennsylvania!!, perhaps 

Permo-Carboni f erous. 

Devonian............... Rampart formation...

Older than Devonian Fortymile formation.. Uncomformity ?..

Older than Devonian .... Birch Oreek schists .. Conformity ?-

Lithologic character.

Gray, green, and black shales, 

and thin siliceous beds.

Limestone, shales, slate, grit, 

quartzite, conglomerate, chert, 

and greenstone partly tuffaceous.

Schists and crystalline limestones.

Quartzite and schists.

The succession in the older metamorphic terranes north of the Yukon is hardly 

as well established as might be inferred from the multiplicity of formation names. 

Sehrader's first account" of the geology, based on an exploration in the Chandlar 

and Koyukuk basins, gave the sequence of pre-Devonian rooks about as follows:

The Rapid schist, regarded as the base of the sedimentary rocks, is a biotiteschist, often carrying garnet and other metamorphic minerals, but the published 

description does not show any marked difference between it and the schists associated with Schrader's so-called "basal granite" already referred to. The second 

horizon, termed "amphibolite-schist," is described as fine grained and pale green 

in color, but as it also is made to include a quartz-mica-schist, it would not seem 

to be very different from the older Rapid schists, or the younger Lake quartzite 

schists, and its green fades might be an altered intrusive. The Lake quartzite

(i Brooks, A. H., Reconnaissance in Tanana and White river basins: Twentieth Ann. Kept. U. S. Geol. Survey, pt. 7, 

1900, 465-466.

In another report, entitled "A reconnaissance from Pyramid Harbor to Eagle City" (Twenty-first Ann. Rept. U. S. 

Geol. Survey, pt. 2, 1900, pp. 357 and 358) the writer grouped all the gold-bearing rocks together under the name Kotlo 

series, which would include the Birch Creek, Fortymile, and Rampart series, but now that more detailed studies have 

been made, the name " Kotlo " can be entirely eliminated from the stratigraphic nomenclature.

& Summary Rept. Geol. Survey Canada for 1900, p, 41.

oSchrader, F. C., A reconnaissance along Chandlar and Koyukuk rivers: Twenty-first Ann. Rept. U. S. Geol. Survey, 

pt 2. 1900, pp. 472-476.
LOWER PALEOZOIC ROCKS. 215

schists, the next younger horizon, is apparently essentially a mica-schist, and mineralogically does not differ from the two older formations except in the presence of 

graphite. These three formations are lithologically so similar and their succession 

seems so much in doubt that it appears they can here be grouped together. Thej* 

form a, broad belt of highly metamorphosed sediments, with some intrusives, which 

are succeeded on the north b}' heavily bedded crystalline limestone and mica-schists, 

termed the "Bottles series," and there is some evidence that the latter may rest 

uncomfonnably on the older rocks.

In Schrader's 3 second journey he studied a section parallel to and 100 miles to 

the west of his first section. This yielded far more definite results, but unfortunately he was able to correlate only in part the formations in the two sections. 

The Skagit formation, made up of heavily bedded crystalline limestones and micaschists, is placed at the base. This yielded some obscure organic remains which 

indicate that it is not older than the upper Silurian. Some mica-schists and quartzmica-schists outcropping south of the Skagit were called the "Totsen series." The 

contact between these rocks and the Skagit was not exposed, but Schrader 6 appears 

to have regarded the Totsen as the younger, though his statements* on this point 

are not entirely in accord. The evidence presented might almost equally well be 

interpreted as indicating that the Totsen underlies the Skagit, and might be correlated with the Rapid and Lake schists which lie to the east in the extension of the 

strike, a correlation made by Schrader in his table. c If this proves to be the case, 

the two crystalline limestone horizons, the Skagit and the Bettles, are probably 

equivalent. The correlation of Schrader's parallel sections, borne out by lithologic 

similarity and by structure, is suggested to be as follows: In both sections micaschist, quartz-niica.-sch.ist, and greenstone, or amphibolite-schist, are succeeded to 

the north by heavy-bedded white crystalline limestone with intercalated schist 

layers. If the writer's interpretation be correct, the equivalencj7 of Schrader's 

pre-Devonian terranes would be thus:

(Upper Sil.?) Skagit formation=Bettlea series. 

Totsen series and greenstone schist=Rapid, Lake, and amphibolite schists.

It will be evident that this succession resembles that of the oldest sediments of 

the Yukon-Tauana region, for the lower horizon of mica- and quartz-schist is similar 

to the Birch Creek schists, while the upper, consisting of crystalline limestones and 

mica-schists, is not unlike the Fortymile rocks.

Some metamorphic beds are exposed along the John River Valley and in the 

heart of the Endicott Mountains, but these Schrader believes to be younger than the 

terranes which have been described, and places in his "Fickett series" (Carboniferous). Schrader's "Stuver series" is probably Devonian or younger, and will be 

described below.

Nothing is known of the westward extension of these metamorphics, except in 

the area studied by Mendenhall'' during his exploration of the Alatna and Kobuk

« Schrader. F. f!., A reconnaissance in northern Alaska; Prof. Paper U. S. Geol. Survey No. 20, 1904, pp. 55-62. 

6Ibid., pp. 58, 59, (>5, and 97. 

«Ibid., p. !)7.

I'Mondenhall, W. <;., A reconnaissance from Fort Hamlin to Kotzebue Hound: Prof. Paper I*. S. Geol. Survey No. 10, 

190-2. pp. SI-36.
216 GEOGRAPHY AND GEOLOGY OF ALASKA.

valleys. He was unable to subdivide the semicrystajline rocks which he encountered in his rapid journey and grouped them together as a " metamorphic complex." 

The members of this great group include schists of various types, limestones, 

quartzites, and greenstones, and resemble lithologically the older terranes of other 

parts of Alaska. Mendenhall traced these rocks westward to Kotzebue Sound, and 

indicated that in a general way they were the equivalent of the metamorphic terranes of the Seward Peninsula.

The accumulation of geologic data regarding the Seward Peninsula has gone on 

intermittently since 1899, and the close of the season of 1903 saw the completion of 

the reconnaissance surveys throughout the peninsula. The facts here presented are 

based on the writer's own field work in 1900," but are modified by the facts learned 

by Collier, who extended the reconnaissance work in 1901* and again in 1903.'' 

Other contributors have been Mendenhall,'' who made a reconnaissance in the Norton 

Bay region in 1900 and in 1901 e touched the northern coast during an exploration 

already referred to, and Moffit,^" who completed the reconnaissance mapping of the 

northeastern portion of the peninsula in 1903.

Most of the bed-rock series is probably older than the Devonian, and the 

terranes vary from highly crystalline schists to those which are but little altered, as 

the metamorphism seems to have been of a rather local character. The stratigraphic succession is now fairly well determined, though only one formation has on 

paleontologic evidence received a definite assignment in the time scale. Beginning 

with the oldest, the general succession is as follows: Mica-schist and crystalline 

limestone (Kigluaik series), graphitic quartzites (Kuzitrin series, uneonformably overlain by mica-schists), then massive limestones overlain by mica-schists 

(Nome series). The massive limestone of the Nome series, called the Port Clarence 

limestone, has yielded Silurian fossils.

As first defined, the Kigluaik series is made up of highly crystalline limestones 

and mica-schists cut by many massive granite dikes. It is typically exposed in the 

Kigluaik Mountains. Collier's late studies have shown that the series also includes 

some gneissoid rocks and some highly graphitic schists. They are apparently 

conformably overlain by the Kuzitrin series, which is typically made up of a highly 

graphitic quartzite. As the Kuzitrin series has not been recognized throughout the 

area it may have been in part removed by erosion before the deposition of the 

succeeding beds of the Nome series, which are apparently unconformable.

The Nome series, the next horizon, is a group of rocks of great diversity of 

lithologic character. A considerable thickness of mica-schists, containing quartz 

and some albite, forms the basal member. Above this is massive limestone, locally 

semicrystalline, called the Port Clarence limestone. The first fossils found in this

a Brooks, A. H., A reconnaissance of the Cape Nome and adjacent gold fields of Seward Peninsula, in a special 

publication, U. S. Geol. Survey, entitled Reconnaissances in the Cape Nome and Norton Bay regions, Alaska, 1900, pp. 

27-41.

& Collier, A. J., A reconnaissance of the western portion of the Seward Peninsula: Prof. Paper IT. S. Geol. Survey 

Xo. 10, pp. 16-24.

< Results not published.

dMendenhal], \V. C., A reconnaissance in the Norton Bay region, Alaska, in 1900, contained in a special publication 

of the U. S. Geol. Survey, entitled Reconnaissances in the Cape Nome and Norton Bay regions, pp. 199-205.

( Collier, A. J., op. cit.; Prof. Paper U, S. Geol. Survey No. 10,1902.

/Moffit, F. H., The Fairhaven gold placers, Seward Peninsula, Alaska: Bull. U. S. GeoJ. Survey No. 247.
LOWEB PALEOZOIC EOCKS. 217

horizon were thought to be of lower Silurian age, but more complete collections have 

shown them to be upper Silurian. The Port Clarence limestone in places is overlain 

by schistose rocks, which constitute the upper member of the Nome series. In the 

southern part of the peninsula these schists are lithologically identical with those 

occurring below the limestone member, but to the north they are represented, in 

part at least, by calcareous schists and with some mica and chloritic schists. The 

whole series has been penetrated by many dikes and sills which are chiefly basic 

rocks.

In the first description of the Nome" series it was pointed out that it might 

include some Mesoxoic beds because of certain obscure fossils collected by Mendenhall in the Fish River Valley. The paleontologists were convinced that these fossils 

were Mcsozoic forms, though the stratigraphic work had led to the correlation of 

the limestone in which they occurred with the limestone in which Silurian forms had 

been found in the Port Clarence region. This made it necessary to believe that the 

" Nome series" included beds as widely separated in the geologic time scale as the 

Mesozoic and Silurian. More complete collections from the same locality have 

shown the error of the tirst determination, and the organic remains are now all 

assigned to the Silurian.

Recently a limestone near Cape Prince of Wales yielded a small collection of 

fossils, which may be Devonian or Carboniferous. If more perfect specimens, show 

that the age of these fossils has been correctly determined, it is quite possible that 

some upper Paleozoic beds have been included in the Nome series.

The presence of Carboniferous beds at Cape Lisburne, 300 miles to the north, 

is attested by abundant fossil* evidence, but the occurrence of Silurian in this 

locality is based on fossils collected and identitied more than half a century ago. 

Schuchcrt, who makes mention of Silurian fossils from this locality in a brief 

summary of the Alaska 6' Paleozoic, published in 1896, has informed the writer that 

as the later collections have revealed no Silurian forms he thinks the determinations 

published by Grewingk rf may be in error.

It has been shown that the oldest sedimentary terranes are usually highly 

altered, and that the stratigraphic sequence is only imperfectly known. Ordovician 

fossils have been found only on the west side of the Alaska Range and Silurian 

only in southeastern Alaska and in the Seward Peninsula. A third locality in 

northern Alaska has yielded a few obscure fossils, which have been provisionally 

assigned to the Silurian. In southeastern Alaska the Silurian beds appear to lie 

near the base of the sedimentary series, and the same probably is true of the 

Ordovician horizon in the Alaska Range. The Silurian of the Seward Peninsula 

overlies a great sedimentary series, as does the supposed Silurian of northern

a Brooks, A. H., Reconnaissance of Cape Nome and adjacent gold fields of Seward Peninsula: Reconnaissances in the 

Cape Nome and Norton Bay regions in 1900 (special publication U. S. Geol. Survey), 1901, p. 31.

''Collier, Arthur J., unpublished notes.

<-Schuchert, Charles, Report on Paleozoic fossils from Alaska: Seventeenth Ann. Rept. V. S. Geol. Survey, pt. 1, 1896, 

pp. 898-906.

<*Grewingk, C., Beitnige zur Kentniss der orographischen und geognostichen Besehaiieriheit der Nordwest Kiiste 

Amerikas mit den anliegenden Inseln: Verhandl. der Huss. K. Mineral. Gesell. zu St. Petersburg, 1848-49. Also 

separate 1850.
218 GEOGRAPHY AND GEOLOGY OF ALASKA.

Alaska. The fossils of all three of the Silurian localities occur in a massive 

limestone, with some intercalated beds of mica-schists or phyllites. Both in 

northern Alaska and in the Seward Peninsula a great series of mica-schists or 

phyllites occurs immediately beneath the Silurian limestone. These facts suggest 

that these limestones belong to the same horizon, but as some of its occurrences arc 

a thousand miles apart the correlation is advanced only as a tentative hypothesis.

The white limestone of the Yukon region (Forty-mile series), known to be of 

pre-Devonian age, like the Silurian fossil-bearing limestone, which it closely 

resembles, also overlies a schist and phyllite series, and this suggests a further 

correlation of this Fortymile series with the other Silurian limestones. The 

correlations suggested would make the Wales (southeastern Alaska), Fortymile 

(Yukon), the Skagit (Koyukuk Valley), and Nome (Seward Peninsula) series 

approximately equivalent in age and show a very extensive development of the 

Silurian. It is of interest to note that these horizons are all mineralized and gold 

bearing.

Below the Silurian there are no paleontologic data, with the exception of 

the Ordovician in the Alaska Range, and of this little is known. The similarity 

of the Birch Creek, Lake, Rapid, Totsen, and Kuzitrin series in lithology, degree 

of metainorphism, and stratigraphic position below the supposed Silurian limestone 

suggests that these formations may belong to the same horizon. Here again all 

of these terranes are mineralized. A necessary corollary of these conclusions is 

that the Kigluaik series of the Seward Peninsula is the oldest sedimentary horizon 

of Alaska.

There is no clue to the age of these schistose rocks. They may be of Lower 

Silurian, Ordovician, Cambrian, or pro-Cambrian age. The fact that Dawson" 

estimates the Cambrian rocks in British Columbia to have a thickness of 25,000 

to 40,000 feet makes it plausible to regard those rocks as in part, as least, of 

Cambrian age.

Igneous rocks are often associated with these motamorphic sediments, but the 

laws of their local distribution are not known. The iutrusives are of several ages, 

the more recent ones being entirely massive, while the older have often been as 

much sheared as the schists with which they are associated. The quartz veins 

seem to be concomitants of the igneous rocks, and, as they are the source of the 

placer gold, the distribution of the intrusives is a matter of economic importance.

DEVONIAN.

The geologic map (PI. XXI) does not indicate the very wide distribution 

of the Devonian horizons, for they are included in part with the Carboniferous 

and in part with the undifferentiated Paleozoic. Several rock groups have been 

assigned to the Devonian, but only one is definitely known to find place in it. 

This, a siliceous blue limestone, with usually an abundant coral fauna of middle 

Devonian typos, has been identified in nearly all parts of the province which have 

been visited by geologists. The Devonian rocks are usually much less metamorphosed than the older Paleozoic sediments, to which they seem to bear an unconf ormablc relation. Siliceous limestones (middle Devonian fossils) and slates, which

a. Geological record Rocky Mountain region Can.: Bull. Geol. Soc. America, vol. la, 1901, pp. 64-68.
DEVONIAN ROCKS. 219

outcrop in a small area in the southern part of the Alexander Archipelago, were 

called the " Valleuar" series," and seem to rest unconforrnably on the Wales series 

(Silurian ?). The same horizon probably occurs at Kuiu Island and at Glacier* Bay, 

and probably has a rather wide distribution in southeastern Alaska.

The Nikolai greenstone in the Copper River region, probably of Devonian or 

Carboniferous age, comprises a series of volcanic c flows, usually of diabasic character, and conformably overlain by the Chitistone limestone (Permian ?) provisionally assigned to the Carboniferous. The age of the Nikolai is uncertain, but it 

is worthy of note that its lithology and probable stratigraphic position are similar 

to the Rampart series (Devonian), to be described below.

The Welleslej'^ formation, which is composed of a basal member made up of 

heavy conglomerate, and an upper member, largely of clay slates, has been 

recognized in only a small area in the upper Tanana and White river basins, 

where it rests unconformably on greenstone schists. A few fragmentary fossil 

remains led to its assignment to the Carboniferous or Devonian, and as the known 

occurrences of the former in the immediately adjacent region are all limestones, 

the Wellesley is probably Devonian.

Mendenhall* found a similar formation in the Copper River basin, about 150 

miles to the west, and called it the "Chisna group." It consists of conglomerates, 

quartzites, arkoses, with some calcareous beds and an abundance of tufaceous 

material and igneous rocks. Though Mondenhall provisionally assigns this to 

the Carboniferous, the evidence seems equalh' strong that it may be Devonian, 

and in any event the Wellesley and Chisna are probably synchronous deposits 

and may represent the base of the Devonian. Eldridge's-' "Cantwell conglomerate," 

a series composed of conglomerate and coarse sandstone, may be a western extension 

of the Chisna. A heav}r conglomerate, 9' sometimes associated with tufaceous 

deposits, outcrops along the western front of the Alaska Range and overlies 

unconformabry the more highly altered sediments (Silurian or Ordovician ?). This 

formation resembles the Chisna and Wellesley, but the correlations are of doubtful 

value, because a similar conglomerate occurs in association with a Mesozoic or 

Tertiary coal-bearing horizon of this district. The "Stuver series," which occurs 

500 miles to the northwest, near the Arctic front of the Rocky Mountains, is also 

largely made of a conglomerate, and may be of the same horizon. It is described 

below.

In detached areas along the western front of the Alaska Range/' a blue siliceous 

limestone yielded middle Devonian fossils at several localities, but is so closely 

infolded with older rocks, that it had to be mapped with the undifferentiated Pale-

(i Brooks, A. H., Preliminary report on the Ketchikan mining: district: Prof. Paper u. S. Geol. Survey No. 1, 1902, 

pp. 42-43.

blbicj., p. 21.

<' Schrader, F. C., and Spencer, A. C., The Geology and Mineral Resources of a Portion of the Copper River District, U. S. 

Geol. Survey, 190], pp. 40-43.

d Brooks, A. H., A reconnaissance in the Tanana and White river basins: Twentieth Ann. Kept. V. S. Geol. Survey, pt. 

7, 1900, pp. 470-472.

« Mendenhall, W. C., Seology of the central Copper River region, Alaska: Prof. Paper U. S. Geol. Survey No. 41.

/Eldridge, G. H., A reconnaissance in the Sushitna basin and adjacent territory: Twentieth Ann. Kept. U. S. Geol. 

Survey, pt. 7, 1900, p. 16.

y Brooks, A. H., An exploration in the Mount McKinley region, U. S. Geol. Survey. (In preparation.)

*Ibid.

17211 No. 45 06 15
220 GEOGRAPHY AND GEOLOGY OF ALASKA.

ozoic. Fifty miles to the west Spurr a found a considerable area of gray limestone, 

to which he gave the name Tachatna series. These rocks are generally thin bedded, 

with calcareous, carbonaceous, and chloritic slates and some fine-grained arkoses, and 

yielded middle Devonian fossils. They are unconformably overlain by lower 

Cretaceous beds.

The Rampart series, which thus far has proved the best defined stratigraphic 

unit of the Paleozoic in the central region, seems to reach its greatest development 

in the district roughly denned by the Yukon on the north and west, the Tanana on 

the south, and the international boundary on the east. Spurr, * who named this 

formation, characterized its rocks as dark green, rather massive volcanic diabases, 

with diabase tuffs and intercalated beds of slate and impure limestone. Later 

studies by Collier, Prindle, and the writer show that the Rampart series contains 

also considerable blue siliceous limestone. Spurr assigned the Rampart to the 

Paleozoic, and the discovery of fossils in the limestone shows that it is Devonian 

and is probably a part of the middle Devonian terrane, found elsewhere in Alaska. 

The Rampart series bears an uneonformable relation to the, older Fortymile series 

(Silurian?) and Birch Creek schists, as well as to younger Carboniferous rocks.

Northwest of the Yukon is an igneous complex which Mendenhall c has described 

under the term Kanuti series. These rocks are in many ways very like the Rampart 

series with which he provisionally correlated it. The Kanuti, as defined by him, 

contains no sediments except some hornstone, and appears to include more intrusive 

material than the typical Rampart. The basal members are greenstone and hornstone, which are intruded by basic igneous rocks, succeeded by basalts, tuffs, and 

diabases.

Devonian beds have not been definitely recognized in northern Alaska, for the 

Lisburne horizon, assigned to this system by Schrader, proves, as will be shown 

below, to be Carboniferous (Pennsylvanian). The Stuver rf series, made up of 

conglomerate and quartzites, underlies the Lisburne unconformably along the upper 

part of the Anaktuvuk Valley and may be of Devonian age. Schrader seems to 

have been in doubt as to the,true stratigraphic position of the Stuver series, for in 

one table of the report cited (p. 53) he places it at the base of his sedimentary series 

(pre-Silurian), while in another (p. 97) he puts it well up in the Paleozoic, and 

correlates it with the Lake quartz-schists, a formation which it appears in no way to 

resemble. Its possible correlation with the Chisna and Wellesley formations 

has already been indicated. The degree of metamorphism, as well as other facts 

presented by Schrader, might lead to the inference that the Stuver series represented 

some infolded Mesozoic beds had he not definite proof of its being older than the 

Lisburne. The Fickett series, which occurs to the south, provisionally assigned by 

Schrader to the Carboniferous, contains conglomerates" which are in every way 

identical with those of the Stuver, and had there been opportunity for closer Studies 

it seems possible that they might prove to be of the same horizon.

agpurr, J. E., A reconnaissance in southwestern Alaska: Twentieth Ann. Kept. U. S. Geol. Survey, pt. 7, 1900, pp. 

157-159.

6Spurr, J. E., The geology o{ the Yukon gold district: Eighteenth Ann. Kept. U. S. Geol. Survey, pt. 3, 1898, pp. 

155-169.

o Mendenhall, W. C., A reconnaissance from Fort Hamlin to Kotzebue Sound: Prof. Paper U. S. Geol. Survey No. 10, 

1902, pp. 37-38.

rfSchrader, F. C., Reconnaissance in northern Alaska: Prof. Paper U. S. Geol. Survey No. 20,1904, pp. 60-62.

"Ibid., p. 68.
CARBONIFEBOUS BOCKS. 221

Reference has already been made to the Bettles series, which, according to 

Schrader, is probably Devonian, but is here correlated with Skagit (Silurian?). 

The only evidence of Devonian rocks in the Chandlar basin is furnished by fossils 

collected by Schrader a from the stream gravels of the Chandlar River, but these 

organic remains are obscure and may prove to be Carbonifei'ous. At Cape Lisburne, 

Collier found a series of sandstones and slates whose thickness aggregates more than 

2,000 feet, overlain conformably by Carboniferous (Mississippian) beds (p. 224). 

These he has provisionally assigned to the Devonian.

McConnell* found limestones carrying fossils, probably of Devonian age, at the 

lower ramparts of the Porcupine, which suggests that the Devonian occurs to the 

east. The fragmentary fossils found near Cape Prince of Wales, which may be, 

Devonian, have already been referred to.

The region east of the Rocky Mountains, in the Mackenzie basin, was one 

of extensive depos: tion during Devonian times. McConnell 0 here recognized 

three subdivisions in the Devonian: An upper limestone and dolomite formation 

containing extensive coral remains, and having a thickness of about 300 feet, 

several hundred feet of shales with some limestone, and a lower member, consisting 

of at least 2,000 feet of limestone and dolomite with some quartzite. The last 

was not found to be fossiliferous and may include beds older than the Devonian.

To summarize briefly, the Devonian is represented by limestones and slates in 

southeastern Alaska, and by siliceous limestones and calcareous shales in the 

Kuskokwim region. In the upper Tanana and Copper River basins a heavy 

conglomerate, quartzite, and slate and tufaceous series is provisionally assigned 

to the Devonian, while near the Yukon River this period is represented by a 

great series of volcanic flows, with some siliceous limestones. The presence of 

Devonian rocks in northern Alaska is not yet established on Paleontologic evidence. 

At Cape Lisburne there is a great thickness of sandstones and slates which are 

probably Devonian, but which have yielded no fossils. In the Colville basin a 

heavy conglomerate and quartzite series (Stuver) may be Devonian, though on 

the accompanying table they are included in the Carboniferous.

Though igneous rocks are closely associated with the Devonian beds of the 

Yukon the Kuskokwim basin and southeastern Alaska they seem to be entirely 

lacking in the beds of this age in the northern part of the Territory.

CARBONIFEROUS.

On the geologic map (PI. XXI) the distribution of the Carboniferous is not 

indicated, for it is in part included in the undiflerentiated Paleozoic, in part in the 

Devonian. At least two distinct Carboniferous horizons are present. The one, 

Permian, has been traced in a general way from southeastern Alaska into the Copper 

River basin, and is found again on the Yukon; the other, Lower Carboniferous, 

outcrops in the Copper River basin, on the Yukon, and in northern Alaska.

In southeastern Alaska the presence of Carboniferous is attested by fossils 

from Kuiu d and Admiralty islands.

a Schrader, F. C., Reconnaissance in northern Alaska: Prof. Paper U. S. Qeol. Survey No. 20, 1904, p. 66. 

b McConnell, R. G., Report on an exploration in the Yukon and Mackenzie basins, N. W. T.: Ann. Rept. Geol. Nat. 

Hist. Survey Canada, new series, vol. 4, 1890, p. 133D. 

olbid., pp. 14D-18D. 

a Brooks, A. H., A reconnaissance of the Ketchikan mining district: Prof. Paper U. S. Geol. Survey No. 1, 1902, p. 21.
222 GEOGRAPHY AND GEOLOGY OF ALASKA.

The Ketchikan series, consisting of argillites, with some greenstones and 

limestones, may be of Carboniferous age," but may also include some infolded 

Triassic beds. Spencer, who has recently studied in the Juneau region what 

seems to be a northern extension of the Ketchikan belt of rocks, however, 

found obscure fossils at Taku Harbor, which have been provisionally assigned to 

the Carboniferous. W right* found doubtful Permian fossils in what appeared 

to be the same horizon 100 miles to the north, in the Porcupine gold district. 

It appears then that there is a fairly well-defined belt of rocks, in part, at least, 

Carboniferous, skirting the mainland of southeastern Alaska, and there may be 

other occurrences of this horizon in the islands to the west.

The northwest strike of this series would carry it into the unexplored St. 

Elias Range, but in the White and Copper River basins Permian rocks are known 

to occur. In 1899 the writer c found a heavy bed of southerly dipping white semicrystalline limestone outcropping along the northern base of the St. Elias Range and 

traced it almost continuously from the Kashaw River, a tributary of the West Fork 

of the Alsek, to the Nabesna, a distance of nearly 200 miles, but at only one 

locality, Kletsan Creek (White River basin), did it yield well-preserved fossils, a 

few of which were collected and referred by Schuchert to the Carboniferous, but, 

with a more complete knowledge of the fauna from collections from adjacent regions, 

he has been able to definitely assign this horizon to the Permian. The field 

notes were too meager to permit the differentiation of this limestone from the 

Nutzotin series, a subdivision now abandoned, but intended to include the 

Carboniferous and Devonian. This Permian limestone of the White River is 

succeeded conformably by black slates, which are probably Triassic.

Schrader, three years later, after a more detailed examination of the upper 

Tanana region, found a much larger area of the Carboniferous rocks and collected 

both Permian and lower Carboniferous fossils. The Permian beds he has called 

the Suslota limestone, and the lower Carboniferous the Nabesna limestone.

Still farther west, in the southern foothills of the Alaska Range, Mendenhall^ 

found Permian beds which are composed of 6,000 and 7,000 feet of sandstones, 

shales, and limestones, with intrusive sheets with some pyroelastics, and which he 

termed the Mankomen group. Fossils are sufficiently widely distributed throughout the section to justify assigning the entire succession to the Permian. Such 

a great development of Permian is unknown in adjacent areas, and the determination might be open to question were it not based on a carefully measured 

section and on more detailed studies than have been made anywhere else in the 

province. Similar close work is likely to disclose Permian horizons in other 

districts. The Mankomen is not found in association with an}' younger beds, 

and as it is cut off on one side by a fauljt with a throw of thousands of feet, 

its stratigraphic relations to other horizons are unknown.

On the south side of the Wrangell Mountains the Carboniferous may be 

represented by the Chitistone limestone which rests conformably on the Nikolai

a Brooks, A. H., A reconnaissance of the Ketchikan mining district: Prof. Paper U. S. Qeol. Survey No. 1, 1902, p. It. 

'< Wright, C. W., The Porcupine placer district: Bull. U. S. Geol. Survey No. 236, 191)4.

 'Brooks, A. H., A. reconnaissance from Pyramid Harbor to Eagle City: Twenty-first Ann. Kept. U. S. Geol. Sun'ey, 

pt. 2, 1900, p. 359.

'' Mendenhall, W. C., The geology of the central Copper River region: Prof. Paper l:. S. Oeol. Survey No. 41.
CARBONIFEROUS ROOKS. 223

greenstone (Devonian?), and is succeeded conformably by beds of known Triassic 

age. This formation is a very massive limestone, probably 2.000 feet thick. No 

fossils have been found in it, and its age determination rests solely on correlation 

with the Permian on the north side of the mountains.

North and west of the Copper River basin the reconnaissance surveys have 

not disclosed any Carboniferous beds as far as the Yukon near the Arctic Circle. 

At the so-called Calico Bluffs, Collier found a series of closely folded semicrystalline limestones and black slates, which yield lower Carboniferous fossils. 

A few miles below these rocks are unconformably overlain by a conglomerate 

limestone and slate series which carries Permian fossils. This is an interesting 

locality because it makes known an erosional interval within the Carboniferous 

which has not been recognized elsewhere in Alaska. Spurr a included both these 

groups of Carboniferous in his so-called Tahkandit series, which was intended 

to em-brace both the Carboniferous and the Devonian. Prindle and Hess have 

recently found Carboniferous fossils in limestone which occurs about 50 miles 

east of Fort Hamlin.

During his exploration of the Anaktuvuk, in northern Alaska, Schrader 

traversed a belt of phyllites, chloritic schists, limestones, slate, sandstone, quartzite, 

grit, and conglomerates, about 50 miles in width. In spite of the heterogeneity of 

these rocks and the uncertainty of their interrelations, the hasty character of the field 

observation made it necessary to group them in one formation, the Fickett * series. 

The only fossils encountered were in the stream gravels and were evidently derived 

from beds in this series, and on this evidence the entire succession was provisionally 

assigned to the Lower Carboniferous. The Fickett overlies the Skagit (Silurian?) 

on the south by an unconformable overlap, and on the north it is cut off by a 

fault from the Lisburne (Carboniferous). Schrader states that the Fickett and 

Lisburne series bear an unconformable relation.

The Fickett series, which may have a thickness of 8,000 to 10,000 feet, has a 

basal member made up of shale, slate, and limestone, succeeded by quartzite, grit, 

and conglomerate, and then by slate and micaceous sandstone. It is in this part of 

the section that the limestone is supposed to occur which yielded the Carboniferous 

fossils of the stream gravels. A still higher member includes sandstone, limestone, 

quartzite, schists, slate, and conglomerate, succeeded by quartz-schists and green 

chloritic schists, the latter often cut by quartz veins. It is not made clear why the 

most highly altered members should occur at the top of the series, for while it is true 

that these metamorphosed rocks lie near one of the axes of intense folding it would 

be expected that the same metamorphic effect would have been noted at the northern 

limit of the section where another locus of extreme deformation was observed.

Schrader, fully realizing the incompleteness of his field notes, states that possibly 

beds of Mesozoic age may have been included in his Fickett series. From the standpoint of historical geology the foregoing adds little to stratigraphic knowledge 

except the mere fact of the presence of a Carboniferous horizon in this thin area.

The so-called Lisburne series, forming a second horizon in the Carboniferous of 

northern Alaska, is made up of crystalline^ limestones and intercalated shales.

" Spurr, J. E., Geology of the Yukon gold district: Eighteenth Ann. Kept. U. S. Geol. Survey, pt. 3,1898, pp. 169-175. 

^Schrader, F. C., A reconnaissance in northern Alaska: Prof. Paper 0. S. Geol. Survey No. 20, 1904, pp. 67-72. 

-Ibid., pp. 62-B7.
224 GEOGRAPHY AKD GEOLOGY OF ALASKA.

Schrader. who defined this series, recognized it in the Colville basin and also 400 

miles to the west at Cape Lisburne. He assigned it to the Devonian, primarily on 

the basis of fossil evidence, but the more complete collections from the Cape 

Lisburne locality made by Mr. Collier indicate that these rocks are Carboniferous 

and probably younger than the Fickett series. In the Colville basin the Lisburne 

rocks on the south rest on the Stuver series (Carboniferous or Devonian?) and on the 

north at the base of the range give way to Lower Cretaceous beds.

Mr. Collier measured the following section of Carboniferous rocks at Cape Lisburne:

Stratigraphy at Cape Lisburne.

System.

Carboniferous (Pennsylvaniari).

Formation. Thickness, etc.

8, 000' ±

Conformity 

1,000'i

Conformity 

500'±

Conformity 

2, 000'+

Lithologic character.

A Massive limestones interstratified with white cherts. 

Extensive coral and bryozoan fauna. 

B Thinly bedded shales, 

slates, cherts, and limestones. Fauna includes

cephalopods, and lamellibranchs. 

C Thinly bedded black 

shales, slates, and limestones ; 

several coal beds; lower 

Carboniferous flora, brachiopods, and coral fauna.

slates. Ko fossils found.

The lowest member of the Carboniferous here indicated carries fossils which are 

probably of the same horizon as those found by Schrader in his Fickett series. No 

exact equivalency between the two horizons can, however, be established because the 

Fickett appears to include a vast thickness of very heterogeneous beds, whose age 

determination must await further investigations.

Collier has found Carboniferous fossils in the limestones which are exposed on 

the east flank of Cape Mountain near the western end of the Seward Peninsula, and 

these are provisionally correlated with the Lisburne series. The same horizon 

probably also occurs on St. Lawrence Island where one Carboniferous fossil has 

been found by Collier.

To summarize briefly: A belt of Carboniferous rocks (probably Permian) has 

been fairly well traced throughout southeastern Alaska; the continuation of the 

strike of these would cany them into the White, Tanana, and Copper River 

basins, where there is a very extensive development of Permian beds and also 

some lower Carboniferous rocks; Permian beds have also been found on the 

Yukon, near the Arctic Circle, resting unconformably on strata of lower Carboniferous age. In northern Alaska the presence of two Carboniferous horizons is 

established by fossil evidence, though there is little definite knowledge of their 

extent or stratigraphic and structural relations. In all except this northern field 

igneous intrusives are found cutting the Carboniferous rocks, and in southeastern
ME80ZOIC BOCKS. 225

Alaska it is probable that some of the associated greenstone schists are ancient 

lava flows. In the Copper River basin volcanic roeks are characteristic accompaniments of the sediments referred to the Permian.

Of the adjacent provinces the Mackenzie seems to contain no Carboniferous, or 

at least it was not recognized by McConnell in his explorations. In British Columbia, however, Dawson" has found this period well represented, chiefly by limestones. 

These limestones he has traced northward into the Yukon Territory, but not to the 

Alaskan boundary. They are in places accompanied by a large amount of volcanic 

material and resemble the rocks of the Mankomen group. These rocks are generally 

thin bedded, with calcareous, carbonaceous, and chloride slates, and some fine-grained 

arkoses and yielded middle Devonian fossils. They are unconformably overlain by 

Lower Cretaceous beds.

MESOZOIC. 

GENERAL STATEMENT.

The Mesozoic is well represented in Alaska, where all three of its larger subdivisions have been recognized. The Triassic and Jurassic have been identified only 

in the Pacfic Mountain province and near Cape Sabine, in northern Alaska, but 

Cretaceous rocks are found not only at these localities, but also in the Yukon basin 

and in the Arctic slope region.

Three large areas of Mesozoic terranes are indicated on the geologic map 

(PI. XX). One stretches along the western shore of the Pacific, extending in 

somewhat broken belts northeast into the Copper River basin, north into the heart of 

the Alaska Range, and southwest into the Alaska Peninsula, the larger part of which 

is composed of Mesozoie rocks. A second area of Mesozoic lies in the lower part of 

the Kuskokwin Valley and stretches northwestward to the Yukon and up its tributary-, 

the Koyukuk, to the base of the Rocky Mountains, where it overlaps unconformably 

on the Paleozoics. The southern belt its composed of Triassic, Jurassic, and Lower 

Cretaceous roeks, while the northern is probably largely made up of Cretaceous 

beds. A third area of Mesozoic rocks, which includes Jurassic and Lower and Upper 

Cretaceous terranes, forms an east-west belt north of the Endicott Range, and has 

been identified in the Colville basin and again at Cape Lisburne. The eastward 

extension of this belt is found in the Cretaceous rocks exposed along the watershed 

between Porcupine and Mackenzie rivers. Besides the above large belts some small 

areas of Mesozoic rocks occur in southeastern Alaska.

In the following pages the undifferentiated Mesozoic, the Triassic, and Jurassic 

will be discussed together, and will be followed by an account of the Upper and Lower 

Cretaceous. This grouping under distinct headings is justified by the fact that the 

Cretaceous horizons are usually found to be fossiliferous, and their distribution is, 

therefore, more definite!}7 established than either the Triassic or Jurassic. Then, 

too, the Cretaceous is usually not as highly deformed and metamorphosed as the 

lower subdivisions of the Mesozoic. The same grouping has been followed on the 

map (PI. XX), where the undifferentiated Mesozoic, Triassic, and Jurassic are indicated by one color and the Upper and Lower Cretaceous by another.

<rThe geological record in the Rocky Mountain regionin Canada: Bull. Geol. Soc. America, vol. 12, 1901, pp. 69-72.
226 GEOGRAPHY AND GEOLOGY OF ALASKA.

TRIASSIC AND JURASSIC.

Dawson's " Vancouver a series" includes a great but undetermined thickness of 

volcanic material, intercalated with arg-illites and limestones, which carry Triassic 

fossils and which occupy large areas on Vancouver Island and on the Queen 

Charlotte Islands. As the Vancouver beds are not always easily separated from 

the underlying- Carboniferous, in reconnaissance mapping it has been found 

impossible to indicate them as distinct stratigraphic units.

It is to be expected that this Triassic series will be found in the adjacent parts 

of Alaska, but up to the present time it has not been positively identified. It has 

been shown that certain rnetamorphic terranes carry Permian fossils, and it is 

quite possible that Triassic beds may be infolded with these, as is the case with the 

Carboniferous of Queen Charlotte Islands. This view is borne out by some obscure 

fossils (probably Mesozoic) which have recently been found by Prindle near Fort 

Wrangell. While reconnoitering the southern part of the Alexander Archipelago 

a succession of conglomerates, black shales, and slates was encountered and 

called the Gravina* series, from the name of the island where they occur. These 

rocks are closely infolded with the Vallenar series (Devonian), but the two 

formations are probably separated by an unconformity. So little was learned of 

the distribution and structural relations of this horizon that the wisdom of giving 

it a distinct name now seems open to question. The Gravina was correlated 

with Dawson's Queen Charlotte group (Cretaceous), but on reviewing the evidence 

its identity with the Vancouver series (Triassic) seems equally probable. In 1904 

Wright found a conglomerate and slate series on Admiralty Island which yielded 

Lower Cretaceous or Jurassic forms.

In the same insular region there are large areas of massive, basic, igneous rocks, 

chiefly of effusive origin, which were grouped together under the name Kasaan 6' 

greenstone, and were provisionally assigned to the Mesozoic. On the Queen 

Charlotte Islands to the south rocks of similar character occur in both the 

Triassic and in the Cretaceous, and the Kasaan effusives may belong to either 

period, but in the report cited were provisionally placed in the Cretaceous and 

correlated with the rocks of the Queen Charlotte group.

Emerson, d who spent two months in skirting the Alaska coast from Dixon 

Entrance to Bering Strait as a member of the Harriman party, has made some 

important contributions to Alaska geology, but some of his correlations appear 

hardly justified on the scant evidence obtained. Emerson extends Dawson's Vancouver series to include not only the Triassic but also the Jurassic and then assigns 

to it extensive areas of sedimentary and igneous rocks, of whose stratigraphic position 

little or nothing is known. The inclusion of supposed Jurassic beds in the Vancouver 

seems particularly unfortunate in view of the fact that it already probably embraces 

a part of the Carboniferous. On this point Dawson^ says: "It [Vancouver series] 

is associated often with very similar rocks of the Carboniferous period, already

aDawson, G. M., The geological record in the Rocky Mountain region of Canada: Bull. Geol. Soc. America, vol. 12, 

1901, pp. 57-92.

. ?> Brooks, A. H., A reconnaissance of the Ketchikan mining district: Prof. Paper U. S. Geol. Survey No. 1, 1902, p. 45. 

 Ibid., pp. 49-60.

d Emerson, B. K., Harriman Alaska Expedition, vol. 4, pp. 11-54. 

' Geological record in the Rocky Mountain regrion of Canada: Bull. Geol. Soc. America, vol. 12, 1901, p. 73.
TRIASSIC AND JURASSIC KOCKS. 227

referred to as existing in the same orographic belt, and it yet remains to draw a 

distinct line between the two series." Moreover, the close of the Triassic seems to 

have been marked by a dynamic revolution which sharply differentiated the Triassic 

from the Jurassic.

Emerson includes in the Vancouver the metamorphic sediments adjacent to the 

Coast Range intrusives, near Fort Wrangell, and in part at least Paleozoic, and the 

much less altered sediments of Sitka. These latter may be Mesozoic, but seem to 

offer no stratigraphic tie point with the schists at Fort Wrangell or with the Triassic 

of Vancouver Island. It is of great value to the stratigrapher to know that the 

Yakutat formation, near Mount St. Elias, the Orca series of Prince William Sound, 

and some sedimentary rocks at Wood Island are synchronous deposits, but the correlation of these supposed Jurassic beds with the Vancouver series (Triassic), whose 

nearest known outcrops are at least 600 miles away, appears but to add confusion to 

stratigraphic nomenclature. This is not by any means the most sweeping correlation 

contained in this work, for, on the basis of a seemingly hasty examination, outcrops 

on the east shore of Port Clarence, in the Seward Peninsula, which are most likely 

Silurian, are also assigned to the Vancouver series, though the nearest known Vancouver is nearly 1,500 miles distant. The writer feels impelled to make these 

criticisms in the interests of stratigraphic nomenclature, especially as the opinion of 

the author of the volume under discussion will undoubtedly have great weight 

among geologists.

On the west side of Baranof Island near Sitka there is a series" of conglomerates, feldspathic sandstones, and slates, with some tuffs and intrusives, whose 

stratigraphic position is unknown. On the basis of a very hast\r examination of a 

few outcrops, in 1901, the writer suggested that these beds might be of Tertiary * 

age, but results of the examination by Emerson and other members of the Harriman 

party and more recently that of F. E. Wright show them to be more highly altered 

than the Tertiary of this province, and they may therefore provisionally find place 

in the Mesozoic.

Two hundred miles to the west is the deep indentation of the coast line called 

Yakutat Bay, and some knowledge of the geology of this region is furnished by the 

explorations of Russell c and by the more recent observations of Gilbert and other 

members of the Harriman party, who spent a few days on the inlet. Russell gave 

the name Yakutat system to a succession of gray and brown sandstones, which in 

places are coal bearing, but he was not able to establish their age. In his first 

report he was inclined to place them above his Pinnacle system, in the upper part of 

which he found Pliocence or Pleistocene fossils, but as both formations included 

indurated and highly folded and faulted beds the assumption of Pleistocene age 

seemed hardly warranted. During the second journey Russell was able to prove that 

the Pleistocene fossils came from morainic material and probably were in no way 

connected with the bed rock. While this discovery was of great importance in its 

bearing on the physiographic history, it left the Yakutat and Pinnacle systems,

ii Harriman Alaskan Expedition, vol. 4, pp. 47 and 48. 

!>Prof. Paper U. S. Geol. Survey No. 1,1902, p. 26.

< Russell, I. C., An expedition to Mount St. Elias, Alaska: Nat. Geog. Mag., vol. 3, 1890, pp. 167-175; Seeond expedition 

to Mount St. Elias, Thirteenth Ann. Kept. L*. S. Geol. Survey, pt. 2, 1893, pp. 7-91.
228 GEOGRAPHY AND GEOLOGY OF ALASKA,

which are not unlike in lithology and may be of the same age, without any stratigraphic tie points. In this region the Harriman party collected some obscure fossils 

which have been assigned to the Jurassic by TJlrich. a If this age determination is 

correct, it shows an extensive development of the beds of Jurassic age along the 

southern flank of the St. Elias Eange.

One hundred miles to the west, near Controller Bay, where the presence of 

petroleum has led to some geologic investigations, Martin* found a series of 

slightly metamorphosed sandstone, limestone, and shale, characterized by colors 

vaiying from gray to dull red and green. He was unable to assign any more 

definite place to this series than probablj- pre-Tertiaiy; but as the rocks lie in 

the strike of the Yakutat series and accord with it in lithology and structure, 

it is fair to assume that they represent a western extension of the same group 

and are of Mesozoic age.

In Prince William Sound, 100 miles to the west, the same series appears to 

be well represented by arkoses, sandstones, and shales, with some black limestones 

and occasional beds of conglomerate, together with considerable diabase or basalt. 

These beds are closely folded and jointed, are very similar to those of the 

Controller Bay region, and were first described by Schrader c under the name 

Orca series. A few obscure plant remains pointed to a Tertiary or Mesozoic age, 

and the formation was provisionally assigned to the former. Some more knowledge of the Orca resulted from the investigations of Schrader"' and Spencer two 

years later, but its age would have still remained in doubt had not the Harriman 

party* here again found the organic remains that are so characteristic of Yakutat 

rocks. This discovery was made known in sufficient time to be inserted in the 

Schrader and Spencer report,-'' and the Orca was there referred to the Jurassic.

To the west of Prince William Sound the rocks of the Chugach Mountains 

bend sharply to the south and find their continuation in the highlands of the 

Kenai Peninsula. This change of strike seems to carry the Orca series into the 

peninsula and to Kodiak Island. This is probably the case, for Mendenhall's 9' 

Sunrise series, a succession of arkoses, sandstones, and slates, was traced by him 

from the western part of Prince William Sound into the Kenai Peninsula. The 

identity of a part of the Sunrise with the Orca can not be doubted, though the 

former may quite possibly include a part, if not the whole, of the Valdez formation. Moffit,A who has recently studied this region, describes these rocks as 

follows:

' The eastern portion of Kenai Peninsula and the region about the head of 

Turnagain Arm present a succession of rocks, which, as a whole, are of remarkably 

uniform appearance and composition. They are of sedimentary origin and consist

oTJlrich, B. O., Fossils and age of the Yakutat formation: Harriman Alaska Expedition, vol. 4, 1902, pp. 125-146.

i> Martin, G. C., The petroleum fields of the Pacific coast of Alaska: Bull. V. S. Geol. Survey No. 250, pp. 12-13.

cSchrader, F. C., A reconnaissance in the Prince William Sound and Copper River region: Twentieth Ann. Rept. 

U. S. Geol. Survey, pt. 7, 1900, pp. 404-408.

dSchrader, F. C., and Spencer, A. C., The Geology and Mineral Resources of a part of the Copper River region: U. S. 

(ieol. Survey, 1901, pp. 37-40.

e Harriman Alaska Expedition, vol. 4, 1902, pp. 49-50.

/ The apparent contradictions in this report as to the age of the Orca were not the fault of the authors, as the changes 

were made during their absence on field duty.

ff Mendenhall, W. C., A reconnaissance from Resurrection Bay to the Tanana River: Twentieth Ann. Rept. U. S. Geol. 

Survey, pt. 7, 1900, pp. 305-307.

AMofflt, F. H., Thegold placers of Turnagain Arm: Bull. I". S. Geol. Survey NT o. 259. 1905, p. 93.
TBIASSIC AND JURASSIC EOCK8. 229

chiefly of fine-grained gray and bluish-black slates and gray arkoses. Interstratified 

with these, but in far less amount, are quartzose beds and occasional thin conglomerates In a few places north of Turnagairi Arm this series of rocks, called by Mendenhall a the Sunrise series, is cut by dikes of igneous rocks of an aplitic or granitic 

character."

In 1898 Dall b found obscure fossils, assigned provisionally to the Triassic, in 

a much-contorted slate and sandstone series 011 Woody Island near Kodiak, a 

locality which he, c in company with the other geologists of the Harriman party, 

again visited in 1899; the fossils then collected led to the definite assignment of these 

beds to the same horizon as the Yakutat and Orca series. The determination of the 

Yakutat and Orca series and the beds on Woody Island as synchronous deposits 

is the most important geologic result of the Harriman party, even though the 

absolute position of these terranes in the geologic column must, in the opinion of 

the writer, be still open to doubt.

A closely folded series of rocks, consisting of constant repetitions of arkoses 

and sandstones or graywaekes and shales, underlie the Orca, and occupy a large 

area north of Prince William Sound. These beds were described as the Valdez 

formation by Schrader," who, much perplexed as to their true stratigraphic 

position, placed them in every system of his table of correlations from the Devonian 

to the early Tertiary. In his second season's work, made with the collaboration 

of Spencer, but little more was learned of the age of the Valdez, but it was then 

provisionally assigned to the Silurian/

The stratigraphic relations of the Valdez rocks present one of the most difficult problems which has been met with in Alaska geology. Briefly, the facts are 

as follows: The Chugach Mountains, which border the Copper River basin on the 

south, are largely built up of closely folded sediments of rather uniform composition, embracing feldspathic sandstones, or graywackes, and shales, or slates, which 

are generally schistose, but have been subjected to a somewhat varying degree of 

metamorphism. On the south the Valdez rocks are probably everywhere cut off 

from the sea by the sandstone and shales of the Orca series, which they are supposed 

to underlie. In most instances they continue northward to the alluvial-floored basins 

of the Chitina and Copper rivers, but in a few localities they have been found 

resting on the metarnorphic limestones and schists of the Klutina series (Paleozoic?). 

Across the Chitina Valley, and only a few miles from the northernmost outcrops of 

the Valdez formation, occurs the Chitistone limestone (Carboniferous?), succeeded 

by Triassic and Jura-Cretaceous beds, which are but little altered. The Valdez, then, 

on the one hand differs but little from the Orca series (Jurassic?) in structure, 

lithology, or degree of metamorphism, but on the other in no way resembles the 

less folded and unaltered Triassic and Jura-Cretaceous beds which outcrop within a 

few miles of them on the north.

Though the Valdez and Orca rocks have been regarded as distinct series, the 

published statements fail to reveal any direct evidence of a structural break between

oMendenhall, W. C., A reconnaissance from Resurrection Bay to the Tanana River, Alaska, in 1898: Twentieth Ann. 

Kept. U. S. Geol. Survey, pt. 7, 1898, p. 305.

("Ball, W. H., The coal and lignite of Alaska: Seventeenth Ann. Rept. U. S. Geol. Survey, pt, 1,1896, pp. 871-872.

< Harriman Alaska Expedition, vol. 4,1902, pp. 51-53.

<i Twentieth Ann. Rept. U. S. Geol. Survey, pt. 7, 1900, pp. 408-410

f The Geology and Mineral Resources of the Copper River Region, p. 33.
230 GEOGRAPHY AKD GEOLOGY OF ALASKA.

them, nor is their lithology very unlike. When Schrader and Spencer placed the 

Valdez rocks well down in the Paleozoic, it was before the Orca series had been 

assigned to the Mesozoic. The writer would interpret the facts as showing that the 

Valdez beds are in part at least the stratigraphic equivalents of the Mesozoic rocks 

of the Wrangell Mountains. He is quite prepared to believe, however, that some 

older sediments may have been included in the Valdez series.

Since the Copper River report was written, facts have accumulated which indicate that Mesozoic beds of the adjacent region are often considerably altered. 

Northwest of Cook Inlet the Alaska Range is largely made up of Mesozoic sediments, which are intensely folded, more or less altered, and in many ways closely 

resemble the Valdez rocks. In the Nutzotin Mountains, north of the Wrangell 

volcanic group, Schrader has reported an extensive series of closely folded and 

considerably altered sediments, which resemble the Valdez series, and yet yield 

Mesozoic fossils. These two occurrences, to be described in greater detail, are here 

cited to show that the deformation and metamorphism of the Valdez are not safe 

criteria for age determination.

The Wrangell Mountains are built up of a great series of Tertiary and Recent 

lavas, which rest on a base of gently folded Jura-Cretaceous rocks, which in turn 

overlie a considerable thickness of calcareous sediments carrying Triassic fossils. 

In the Triassic" of the Chitina Valley is a lower member of thin-bedded limestone 

and black shale, having a thickness of about 1,000 feet, and resting conformably on 

the Chitistone limestone (Carboniferous). It carries no fossils, but corresponds very 

closely with the rocks, observed by the writer, overlying the Permian limestone in 

the upper White River basin. The upper member of the Triassic includes at least 

3,000 feet of black shales, with occasional bands of fossiliferous limestone. An 

attempt was made by Rohn,* who, under the auspices of the War Department, made 

a reconnaissance of this field, to divide the Triassic into the McCarthy Creek shales 

and the Kuskulana shales, but this subdivision was abandoned after more detailed 

studies had been made. As no fossils have been found in the lower member, it is 

possible that it may belong with the Chitistone, from which it is not separated by 

any structural break.

The Triassic, which is closely folded, is succeeded unconformably by the 

Kennicott 6' formation of Jura-Cretaceous age, consisting of conglomerates 6' and 

overlain by sandstones, limestones, and shales. This same horizon seems to occur 

about 100 miles to the west in Mendenhall's* "Matanuska series," which is made up 

of conglomerate (a thickness of 1,000 feet was measured) and sandstones, but more 

typically red, green, and black shales, with some intercalated limestone beds, which 

yield Jura-Cretaceous fossils.

The rugged Nutzotin Mountains forming the southern wall of the upper 

Tanana Valley were explored by the writer in 1899, and found to be made up of a 

series of closely folded slates, graywaekes, and impure limestones, with some igneous

<> Geology and Mineral Resources of the Copper Kiver Region, pp. 46-47.

ft Rohn, Oscar, A reconnaissance of the Cliitina and Skolai Mountains, Alaska: Twenty-first Ann. Rept. U. S. Geol. 

Survey, pt. 2, pp. 423, 424, 426, 427, 433.

a Named by Rohn, op. cit., pp. 428, 431, 433.

<* The Geology and Mineral Resources of the Copper River Region, pp. 48-49.

e Mendenhall, W. C., A reconnaissance from Resurrection Bay to the Tanana River: Twentieth Ann. Rept. tl. S. 

Geol. Survey, pt. 7,1900, pp. 307-309.
TR1ASSIC AND JURASSIC ROCKS. 231

rocks along the valley of the Nabesna River. This series, lying between the 

Devonian (Wellesley) on the north and the Permian on the south, seemed an integral 

part of the upper Paleozoic beds, which were grouped together under the name 

Nutzotin" series, a stratigraphic subdivision since abandoned. Schrader, who 

mapped this country in more detail in 1902, found enough fossils to make it evident 

that most of the rocks of the Nutzotin Mountains are of Mesozoic age, though he 

was able to make no subdivisions of them.

Mesozoic rocks seem to have their greatest development in the Alaska Peninsula 

and northward into the Alaska Range. The Pacific shore of the peninsula and the 

western shore of Cook Inlet have been known for upward of half a century as a 

source of Mesozoic fossils, but up to very recent years almost nothing was known 

of the stratigraphy of the region. An account of the early investigations in this 

district is to be found in Dall's'J summary, which shows that Mesozoic fossils, ranging in age from the Triassic to the upper Jurassic or Lower Cretaceous, had been 

found. Spurr" mapped as Jurassic a broad belt of rocks, stretching from near the 

upper end of Cook Inlet southwestward to the limits of his map, near the fiftyeighth parallel, and notes their probable continuance as far south as Port Moller. 

He gives the name Naknek series to some arkoses and conglomerates of this belt, 

which carry Jura-Cretaceous fossils. A part of the area covered by Spurr's map 

has recently been examined in some detail b}- Martin, '' who investigated the oil fields 

of the vicinity and reported about 1,600 feet of sandy shales, with some conglomerates, sandstones, and limestones, with Jurassic fossils, to which he gave the name 

Enochkin formation. These rocks rest uncomforimibly on an igneous complex to 

the west, and are succeeded to the cast by about 2,000 feet of volcanic flows and 

agglomerates, with some shale, probably of Cretaceous age. At Cold Bay, 100 miles 

to the southwest, Martin found Triassic overlain by Jurassic arkose sandstone, with 

some limestone and dark shale.

In 1904 Martin and Stanton continued the stratigraphic study of the Alaska 

Peninsula. f Their results are summarized in the table which follows.

a Brooks, A. H., A reconnaissance from Pyramid Harbor to Eagle City: Twenty-first Ann. Kept., U. 8. Geol. Survey, 

pt. 2, 1900, p. 360.

6Ball, W. H., Report on coal and lignite of Alaska: Seventeenth Ann. Rept., U. S. Geol. Survey, pt. 1, 18%. pp. 8B6-871

' Spurr, J. E., A reconnaissance in southwestern Alaska: Twentieth Ann. Kept., II. S. Geol. Survey, pt. 7, 1900, pp. 235- 

236. Map, pi. 14.

d Martin, G. C., The petroleum iields of the Pacific coast of Alaska: Bull. I'. K. Geol. Survey No. 250.

< Stanton, T. W., and Martin, G. C., The Mesozoic section on Cook Inlet and the Alaska Peninsula: Bull. Geol. Boo. 

America, vol. 16, 1905, pp. 391-110.
232 GEOGRAPHY AND GEOLOGY OF ALASKA. 

Stratigraphy of the Alaska Peninsula.

Age.

Paleozoic ?

Name of formation.

Xaknek formation. . . .

Kodiak slates.

Lithologic character and 

thickness.

2,000 feet.

and flows, conglomerate, sandstone, and 

shale, 5,000 feet.

limestone and conglomerate, 3,000 feet.

possibly lavas.

shale, 2,000? feet.

«

Geographic distribution.

1 few scattered localities

the Alaska Peninsula.

andsouthshoreof Alaska 

Peninsula.

and south shore of Alaska 

Peninsula.

Bay.

shore of Alaska Peninsula.

A section across the southern end of the Alaska Range, through the basin of the 

Skwentna, shows a complex of volcanic and intrusive rocks, forming the foothills of 

the mountains on the east. The stratigraphic position of these rocks, first described 

by Spurr, under the name Skwentna a series, and later studied by the writer, is much 

in doubt. Lithologically they resemble somewhat the igneous complex at Enochkin Bay, and like them they are succeeded unconformably by Mesozoic sediments. 

On the accompanying map (PI, XXI) they are included in the Mesozoic and may be 

provisionally assigned to the Triassic.

The Mesozoic rocks to the west of this complex include a great thickness of 

closely folded sandstones, graywackes, slates, and some limestones, aggregating a 

thickness of probably many thousand feet. This is Spurr's Tordrillo 6 series, which 

he assigned to the Cretaceous, but, as shown by fossils determined by Stanton, it is 

in part at least middle Jurassic/ These rocks are, in many ways, similar to both 

the Valdez series and the Mesozoic beds of the Nutzotin Mountains, and the latter 

rocks lie in the extension of the strike of the Tordrillo series.

Coal-bearing rocks have long been known to occur near Cape Lisburne d on the 

northwest coast of Alaska, and a few fossil plants collected from these beds were 

determined as Mesozoic. The rocks associated with the coal are sandstones, arkoses, 

with some conglomerate, and in places shale and impure limestone, and they carry 

Jurassic plant remains. Schrader called them the Corwin" series and indicated that 

they are older than any of the Mesozoic of the Colville basin.

i Spurr, J. E., A reconnaissance in southwestern Alaska: Twentieth Ann. Kept. II. S. Geol. Survey.pt. 7,1900, pp. 

149-152.

6Ibid., pp. 153-156.

e An exploration in the Mount McKinley region: Prof. Paper II. S. Geol. Survey, No. . (In preparation.)

dBrooks, A. H., The coal resources of Alaska: Twenty-second Ann. Kept. U. S. Geol. Survey, pt. 3, 1901, pp. 530-553 

and 561-563.

e Prof. Paper D. S. Geol. Survey No. 20, pp. 72-74.
TRIASSIC AND JURASSIC ROCKS. 233

Collier," who had much better opportunities for detailed studies in this field than 

any of the previous investigators, has published the following statement in regard to 

the Mesozoic stratigraphy:

"The Mesozoic rocks occur on the coast, about 3 miles east of Cape Lisburne, 

and extend beyond the limits of the area covered by this investigation. They 

consist of two members, of which the older is coal bearing while the younger is not 

only destitute of coal but also of fossils.

"The coal-bearing member, which has been called the Corwin formation, begins 

on the coast line about 26 miles east of Cape Lisburne and about 2 miles west of 

Corwin Bluff. From this point it extends eastward to and beyond Cape Beaufort, 

the eastern limit of the area comprised in this investigation. This formation consists 

of rather thin-bedded shales, sandstones, and conglomerates. The shales which 

form the greater part of the section, vary from greenish-brown calcareous to black 

carbonaceous beds, and in texture from mudstones to tine-grained sandy shales.

"The sandstones occur at infrequent intervals through the formation, in beds 

usually less than 10 feet in thickness. Their outcrops form low ridges, which are 

easily traceable over eroded areas. The conglomerates are made up mainly of 

quartz and chert pebbles, ranging in diameter from one-half to 4 inches. A 

conglomerate bed about 15 feet thick, which reaches the coast at Corwin Bluff, makes 

a distinct ridge from 100 to 200 feet high, which has been traced southeastward 

for about 15 miles, giving a definite key to the stratigraphy of a portion of the field.

"The thickness of the Corwin formation exposed along the coast near Corwin 

Bluff is not less than 15,000 feet. The base of the formation has not been observed, 

but it probably rests unconformably on the Paleozoic rocks.

"Fossil plants collected from it indicate that the age is Jurassic.

"The structure consists of several broad synclines and anticlines, the dips of 

the beds varying from 0° to 60°. There is no evidence of faulting other than minor 

shearing movements parallel with the bedding planes.

"The Corwin formation is conformably overlain by a more arenaceous series of 

sandstones and shales in which neither coal beds nor fossils have been found. The 

contact of these rocks with the Corwin rocks may be seen about 2 miles west of 

Corwin Bluff, whence it extends southeastward for several miles to the limit of the 

area investigated. The western limit of the formation is a well-defined fault line 

extending southeastward from a point on the coast 3 miles east of Cape Lisburne, 

where the formation is in contact with the Paleozoic, which is overthrust. The 

structure of this formation increases in complexity from its base at the top of the 

Corwin formation as this fault is approached; there are intense crumpling and 

numerous minor thrust faults. For this reason it is impossible to estimate the 

thickness of the formation, but the evidence obtained indicates that its minimum 

thickness is not less than 5,000 feet."

Practically nothing is known of the geology east of the Colville, until the 

portage route is reached, which crosses the Rocky Mountains and connects the 

Porcupine with the Mackenzie waters. Here McConnell * has made some geologic 

observations. He showed that no rocks older than Mesozoic (probably Cretaceous)

a Collier, A. J., Coal fields of the Cape Lisburne region: Bull. U. S. Qeol. Survey No. 269, pp. 175-176. 

b McConnell, E. Q., A report on an exploration in the Yukon and Mackenzie basins: Ann. Kept. Geol. and Nat. Hist. 

Survey Canada, new ser., vol. 4, 1888-89, pp. 21D and 119D-120D.
234 GEOGBAPHY AND GEOLOGY OF ALASKA.

were exposed, and that these consisted of quartzites, sandstones, and shales, and 

that the entire thickness of beds referred to the Cretaceous is probably 5,000 feet. 

It has been demonstrated that Mesozoic beds are extensively developed in the 

Pacific seaboard of Alaska, and while many of the rocks along the coast are of 

undetermined age, Triassic, Jurassic, Jura-Cretaceous, and Upper Cretaceous 

fossils have been found. In the Mount Wrangell region the systems are sharply 

differentiated. Mesozoic rocks, probably of Jurassic age, have been traced paralle 

to the coast from Yakutat Bay to Kodiak Island, while in the Alaska Peninsula th< 

Triassic and Cretaceous have been recognized at a few localities, and the Jurassk 

occurs extensively and is continued northward into the Alaska Range. Though the 

known Triassic and .Jurassic beds are not greatly altered in this district, there is 

evidence that some partly metamorphosed sediments, such as those of the Chugach 

and Nutzotin mountains, are Mesozoic. One measured section in the Wrangell 

Mountains revealed 4,000 to 5,000 feet of Triassic, succeeded by several thousand 

feet of Jura-Cretaceous. While here the middle and lower Jurassic are entirely 

wanting, these have been found in the adjacent region with a thickness of at least 

several thousand feet. In the Alaska Peninsula Stanton and Martin found Triassic 

and Jurassic sediments aggregating a thickness of at least 10,000 feet. In northern 

Alaska, near Cape Lisburne, Mesozoic beds, which are probably chiefly Jurassic, 

have been found to a thickness of probably 20,000 feet.

CBETACEOUS.

As it is an open question as to where the division between the Lower Cretaceous and the upper Jurassic terrane should be made, certain formations like 

the Kennicott are referred to the Jura-Cretaceous. If the unconformity at the 

base of the Kennicott is found to be a widespread feature, it may eventually 

serve as a convenient line of demarcation. The following paragraph presents 

this matter briefly:

" Rocks " which have been referred to the Cretaceous have a wide distribution 

in Alaska and adjacent portions of Canada. These have been described in different 

localities under various formation names and have usually been assigned to the 

Lower Cretaceous. The paleontologic evidence obtained as yet is but fragmental, 

and according to Doctor Stanton, consists mainly of the identification of a single 

species Aucetta crassicollis Keyserling, which has been found rather widely distributed in Alaska. This species marks a definite horizon in the Knoxville beds of the 

Lower Cretaceous of California, and also occurs in the Lower Cretaceous of Russia, 

but the genus Aucetta occurs abundantly in the upper Jurassic as well as the Lower 

Cretaceous, and the identification of a single species of that genus represented by 

a few imperfect and fragmentary specimens can not safely be depended on for 

separating Jurassic from Cretaceous rocks. It is probable that all the Alaska 

beds from which Aucetta crassicottis has been reported are Lower Cretaceous, 

though part of them may be Jurassic."

For convenience these Aucella-bearing beds will here be included in the 

Cretaceous, with the reservation that they may ultimately find a place in the

« Brooks, A. H., The coal resources of Alaska: Twenty-second Ann. Rept. U. S. Geol. Survey, pt. 8, 1901, pp. 527-628.
CBETACEOUS BOOKS. 235

Jurassic. An exception has been made in case of the Kennicott and Matanuska 

terraiies, of this Aucella horizon, because they were so intimately associated with 

the Triassic and Jurassic beds that their description was included with them. 

These Aucella-beSLring beds have also been found at Herendeen« Bay on the 

Alaska Peninsula, which indicates the presence in this district of Mesozoic terranes 

varying in age from Triassic to Jura-Cretaceous.

The recent studies of Wright * have revealed the presence of the Aucellabearing beds along the eastern coast of Admiralty Island in a series of conglomerates, graywackes, and slates. Stanton makes the following statement in 

regard to the fossils from these beds:

"The specimens of Aue.ella from Pybus Bay, Admiralty Island, are apparently 

referable to species that in California and adjacent States are characteristic of the 

Lower Cretaceous, AitceHu j>ii>ehii occurring in a lower zone than Aui-ellu crassicolhs. 

The Alaskan specimens probably also come from the Lower Cretaceous, although 

strict correlation is rendered somewhat hazardous by the fact that the genus Aucella 

with similar specific forms ranges down into the upper Jurassic."

Wright has also found a conglomerate sandstone and shale series on Kupreanof 

Island, a few miles south of Admiralty Island, which carries plant remains 

assigned to the Upper Cretaceous. Knowlton reports as follows on these fossils:

"These plants indicate beyond question that the age is Cretaceous, and I would 

place them in the lower part of the Upper Cretaceous, or approximately of 

Cenomanian age.''

It appears that these Upper Cretaceous beds are discordant to Aucetta-be&ring 

terranes of the adjacent region, and that they are conformably succeeded by the 

Kenai (Eocene) rocks, with which they are lithologically identical.

Spurr, 6' in his reconnaissance along the upper Yukon, grouped together some 

conglomerates, sandstones, carbonaceous shales and limestones, and assigned them 

to Jurassic and Cretaceous. Though a part of these are Cretaceous, 3~et the 

name Mission Creek series proposed by Spurr will have to be abandoned, for 

it was applied to beds as widely separated as the Carboniferous and the Tertiary. 

Collier'' found Lower Cretaceous fossils (Aucella) in a series of closely-folded black 

slates, with some limestones and calcareous conglomerates which outcrop along 

the Yukon for nearly 80 miles, at a locality which can be identified on the map 

(PI. XXI) by noting the point of intersection of the one hundred and fortysecond meridian.

An extensive area of Cretaceous beds is represented on the map stretching 

northeast from near Bering Sea to the base of the Rockj^ Mountains in the upper 

Koyukuk basin. This belt is known to be interrupted by both older and 

younger terranes, but within it Cretaceous rocks are believed to predominate. 

Lower Cretaceous beds alone have been identified in the southern part of the 

area, but as the evidence is purely negative it is quite possible that higher 

members of the Cretaceous may yet be found. To the north of the Yukon the 

Cretaceous rocks belong to the middle or upper part of the system, while still

a Brooks, A. H., The coal resources of Alaska: Twenty-second Ann. Kept. D. S. Geol. Survey, pt. 3, 1901, pp. 528-529. 

('Wright, 0. W., A reconnaissance of Admiralty Island. (In preparation.)

" Spurr, J. K., Geology of the Yukon gold district: Eighteenth Ann. Kept. U. g. Geol. Survey, pi. 3, 1898, pp. 169-175. 

d Collier, Arthur J., The coal resources of the Yukon: Bull. D. S. Geol. Survey No. 218, pp. 1M7, 1903.

17211 No. 45 06 10
236 GEOGRAPHY AND GEOLOGY OF ALASKA.

farther north the lowest members are again exposed, overlapping the metamorphic 

sediments at the base of the range.

Spurr" subdivided the Mesozoic rocks of the Kuskokwim Valley into three 

series, all Cretaceous, of which the Holiknuk and Kolmakof series are supposed 

to be synchronous, while the stratigraphic relation of the third the Oklune series, 

which is Jura-Cretaceous to the others is unknown. The Holiknuk series is made 

up of alternating sandstones, argillaceous and siliceous limestone containing fragmentary Cretaceous fossils, and shale and arkose, all thrown up in broad open 

folds. An unconformity determined the line of demarcation between these beds 

and the underlying Tachatna series (Devonian).

A. succession of volcanic rocks of various types occurs to the southwest, and 

these, together with some intercalated tuffs, shales, impure limestones, and arkoses, 

form Spurr's Kolmakof series, supposed to be synchronous with the Holiknuk 

beds. A group of sediments, including shales, impure limestones, with some 

arkoses, received the name "Oklune series" from the mountains where they are 

typically exposed. These beds are referred to the Jura-Cretaceous on the evidence 

of some fragmentary fossils. As far as the facts presented can be interpreted, all 

three of these series may belong to the same horizon. All three exhibit about 

the same amount of deformation and are intruded by igneous rocks of various 

kinds. If they are not of the same age, it is probable that the Holiknuk belongs 

to the Jurassic or the Triassic and that the others are younger.

Cretaceous rocks outcrop almost without break on the lower Yukon from 

the mouth of the Melozi River to the head of the delta and northward into the 

basin of the Koyukuk River. In this part of the Yukon Valley Dall made the 

first geologic observations in the interior of Alaska over forty years ago. In his 

summary of Alaskan * geology, made many years after, he assigned some coalbearing beds to the Kenai (Eocene) and reported that they were succeeded by 

marine fossil-bearing sandstones. Spurr" corroborated Ball's observations, and, 

accepting Eocene as the age of the underlying coal-bearing beds, assigned the 

succeeding strata to the Miocene under the name Nulato sandstone. This conclusion 

seemed to be further supported by fossils from sandstone which were determined 

as Miocene. The stratigraphic position of the coal-bearing beds of the Yukon 

will be considered below, but it will be noted that so-called Kenai of the Yukon 

embraces beds as divergent in age as the Upper Cretaceous and the Upper Eocene. 

The stratigraphic work of Collier, d in 1902, followed by that of Hollick, in 1903, 

and the studies of their collections by Stanton and Knowlton have yielded ample 

proof of the Upper Cretaceous age of both the Nulato sandstone and the underlying coal-bearing beds. These results have not yet appeared in print, but are 

briefly referred to in Colliei*'s report on the coal resources of the Yukon/ In 

short, near Nulato there seems to be exposed a conformable series, consisting of 

sandstones, shales, and conglomerates, which represent continuous sedimentation 

from the middle of the Cretaceous to the Upper Eocene.

«Spurr, J. E., A reconnaissance in southwestern Alaska: Twentieth Ann. Kept. U. S. Geol. Survey, pt. 7, 1900, pp. 

159-169.

<>Dall, W. H., and Harris, G. H., Neocene correlation papers: Bull. U. S. Geol. Survey No. 84, pp. 347-348. 

"Eighteenth Ann. Kept. U. S. Geol. Survey, pt. 3, p. 196. 

(iBull. U. S. Geol. Survey No. 213. 

eBull. U. S. Geol. Survey, No. 218, p. 17.
TERTIARY ROCKS. 237

Schrader's Koyukuk a report makes mention of Lower Cretaceous fossils in an 

impure limestone, associated with volcanic rocks, which outcrop near the sixty-sixth 

parallel, and to the south of these of an impure limestone which carried Upper 

Cretaceous fossils, but assigned the Nulato sandstone to the Miocene. During his 

second journey in this region he was able to add considerable data regarding the 

Cretaceous rock, and gave the name Koyukuk series to beds consisting of impure 

limestone, slate, and some sandstone associated with igneous rocks. This formation 

carries the typical Jura-Cretaceous fossil, Aucella crasxicoUn Keyserling.

Between the northern limit of the Koyukuk and the base of the mountains is a 

broad belt of sandstone and shale, resting on a basal member of conglomerates, whose 

pebbles are derived from the metamorphic sediments (Paleozoic?) which lie to the 

north. These Schrader 6 called the Bergman series, and in his second report provisionally assigned to the Cretaceous, but in his first publication he had called them 

Eocene (Kenai), because they are lignite bearing. The Bergman is supposed to 

overlie the Koyukuk, but, as the contact was not seen, the relations .may be reversed, 

and the Bergman might be Jurassic or Upper Cretaceous. The presence of the coal 

would suggest their correlation with the Upper Cretaceous coal-bearing beds of the 

Nulato region; but this is not a safe criterion, for the coal, which is lignite, resembles 

that of the Kenai (Eocene) rather than that of the Cretaceous, and the series may 

be chiefly lower Mesozoic, with some infolded Kenai beds.

A third extensive development of Cretaceous forms a broad east-west zone across 

northern Alaska, in the Arctic slope province. These rocks Schrader" divided into 

two unconformable groups the Anaktuvuk series (Lower Cretaceous) and the 

Nanushuk series (Upper Cretaceous). The Anaktuvuk is made up of fine, heavybedded sandstones, or arkose sometimes a grit, with little conglomerate the whole 

aggregating at least 2,000 feet. Eesting unconformably on these are sandstone, 

impure limestone, slate, quartzite, and chert, which make up the Nanushuk series. 

The Anaktuvuk carries Aucella crmsicolis Keyserling, making it Jura-Cretaceous, 

while the Nanushuk has yielded Upper Cretaceous fossils. The Nanushuk, like the 

Upper Cretaceous of the lower Yukon, contains coal seams of excellent quality.

The following brief summary may be made in regard to the Cretaceous: The 

lowest member (possibly in part Jurassic) is found widely distributed from southeastern to northern Alaska. It is developed in the Yukon, Kuskokwim, and Koyukuk 

valleys and in the Arctic slope region. Its composition varies from sandstones to 

limestone, but its basal member is usually a conglomerate. The Upper Cretaceous 

has been recognized on Kupreanof Island, in the Alaska Peninsula, on the lower 

Yukon, and in the Colville basin.

CENOZOIC. 

TERTIARY.

Tertiary rocks cover no considerable areas in Alaska, though widely distributed 

in isolated patches, many of which are too small to find a place on a map (PL XXI) 

of this scale. These are in part remnants of larger areas dissected by erosion; in 

part deposits laid down in distinct basins.

a Twenty-first Ann. Rept. U. S. Geol. Survey, pt. 2, 1900, pp. 476-477. 

t> Prof. Paper U. S. Geol. Survey No. 20, 1904, pp. 77-78. 

"Ibid., pp. 74-76 and 79-81.
288 GEOGRAPHY AND GEOLOGY OF ALASKA.

The so-called Kenai group (Upper Eocene or Oligocene) is the lowest and a.lso 

the most widely distributed horizon of this system. The fact that the Kenai is coaibearing has led to its recognition in many locations even by untrained observers. 

but it must be admitted that this apparent easy method of age determination has 

tended toward the conclusion that all the coal-bearing terraiies are of one horizon. 

The deformation of the Kenai group seems to represent the last considerable epirogenic movements in this province. Of the other divisions of the Tertiary the 

Miocene .seems to be rather widely distributed along only the Pacific coast, and 

beds of Pliocene age have been found only on the Yukon and north of the Rocky 

Mountains.

The Tertiary will be discussed under the two headings: "Eocene" and "Miocene and Pliocene.'' Though the stratigraphy of this epoch would seem to present 

fewer difficult problems than the older terrancs, it is but very imperfectly known, 

owing chiefly to the lack of adequate collections of its fossils.

Probabty all the Eocene of Alaska belongs to the Kenai series, which has been 

variously called Oligocene and Arctic Miocene, but is now generally regarded as 

chiefly Upper Eocene, with possibly some Lower Eocene beds. The type locality 

is on the western side of the Kenai Peninsula, where the Kenai group, as first 

defined by Dall," consists of bluish shales, sandstones, conglomerates, lignite seams, 

with abundant terrestrial and fresh-water plant remains, and occasional intercalated 

beds of limestones. Dall named an upper member of the group, consisting of conglomerate and sand layers, Unga beds.

At the type locality the Kenai is made up of only slightly indurated or entirely 

unconsolidated beds. The same terrane has, however, been identified in much' more 

highly altered rocks which carry plant remains and also coal, such as those of Controller Bay, Mantanuska River, and Cantwell River. These facts are difficult to 

reconcile, and it appears that the deciphering of the Alaska Tertiary stratigraphy 

must await further investigation. It seems at least possible that the Kenai series of 

the Pacific littoral may include horizons younger or older than the Upper Eocene, 

and in any event that all the coal-bearing beds of the Pacific coast province are not 

synchronous deposits. The fact that the coals of adjacent parts of British Columbia 

are Upper Cretaceous makes it probable 6 that this horizon is present in the Pacific 

coastal region of Alaska, as has already been found to be the case on Kupreanof 

Island.

Coarse, sandy beds, with some conglomerate, considerable volcanic material, 

with seams of lignite of Tertiary c age, occur on Graham Island, as well as on all the 

islands of the Queen Charlotte group. In the same region are sandstones containing 

marine Miocene or Pliocene fossils and also lignite seams.

Slightly indurated beds of feldspathic conglomerates, sandstones, and shales, 

carrying more or less lignitic coal, have been found at various localities d in the

u Ball, \V. H., and Harris, G. B., Correlation papers: Bull. U. S. Geol. Survey No. 84, pp. 232-249.

bGeol. Nat. His. Survey Canada, 1872-73, pp, 1-100; 1878-79, pp. 1B-100B.

o Dawson, G. M., Queen Charlotte Islands: Geol. Nat. Hist. Survey Canada, 1878-79, pp. 84B-94B.

dDall, W. H., The coal and lignite ol Alaska: Seventeenth Ann. Rept. I'. S. Geol. Survey, pt. 1, 1896, pp. 775-783.
EOCENE ROOKS. 239

Alexander Archipelago and the adjacent parts of the mainland of Alaska. They 

probably do not exceed a few hundred feet in thickness. On Admiralty Island they 

are intimately associated with lava flows, which are of a basaltic and andesitic character. These same beds may be present at Lituya and Yakutat bays, where lignites 

are said to occur." On Admiralty and Kuiu islands these beds have yielded plant 5 

remains referable to the Kenai, and for this reason they have all been assigned to 

that formation, though, as has been shown, Wright found Cretaceous coals in 

southeastern Alaska, and on the adjacent islands of British Columbia coal seams 

occur in strata varying in age from Cretaceous to the Miocene.

At Controller Bay, Martin'' has given the name Ratal la formation to a series of 

argillaceous and carbonaceous shales, with occasional bands of sandstone, limestone, 

conglomerate, and tufa, which from the evidence of a few fossils are provisionally 

assigned to the Tertiary. These beds overlie a series of scmialtcred sandstones, 

limestones, and shales, which have already been correlated with the Orca and 

Yakutat series.

In the same district a group of indurated shales, feldspathic sandstones and 

coal seams, having a thickness of many hundred if not several thousand feet, was 

named the Kushtaka formation. The coal, which is of a bituminous character, is 

totally unlike that of the Kenai of Cook Inlet, and the general structure suggests 

that the Kushtaka overlies the Katalla.

Mention has already been made of Ball's description of the Kenai series of the 

type locality on the peninsula of the same name. Stone/ who recently made a 

detailed study of the coal measures in the Kachemak Bay region, describes the succession as follows:

 'The Kenai formation as exposed in Kachemak Bay is composed of soft, lightgray sandstones and clay shales, with frequently interspersed coal seams. Four 

partial sections of the formation, aggregating 1,765 feet of strata, are given in the 

next chapter. These sections are represented diagrammatically on PI. I, A, and show 

that coal seams from a few inches to 7 feet thick are distributed throughout the portion of the formation represented. It appears also that 350 feet at the top of the 

Falls Creek section, which is the highest geologically, have no sandstone, being composed entirely of shale and coal. It can not be said with certainty that the lower 

portion of the formation is characterized by an abundance of sandstone, and the 

upper portion by a lack of it, although there is a suggestion that this may be the 

case. The sandstones are medium grained, soft, light gray, sometimes iron stained, 

and occur in beds from a few inches to 30 feet thick. Cross-bedding was noted at 

one locality. Some portions of the heavier beds of sandstone occasionally are hard 

and weather out in nodular blocks. In these blocks the best preserved fossil plants 

arc sometimes found. In one locality lenses of grit, or fine conglomerate, occur in 

a sandstone bed. The pebbles are smaller than a half-inch in diameter, and are 

mostly quartz. Sandstones at places grade into sandy shale. Dall' reports coarse

«Dall, W. II., The coal and lignite of Alaska: Seventeenth Ann. Kept. U. S. (Jeol. Survey, pt. 1, 1896, pp. 783-784.

I' Ibid., pp. 775-783.

< Martin, G. C., Tne petroleum fields of the Pacific coast of Alaska: Bull. U. S. Geol. Survey No. 250, pp. 13-15.

<> Stone, R. W., Coal fields of Kachemak Bay and vicinity: Bull. U. S. Geol. Survey. (In preparation.)

f Dall, W. H., Coal and lignite of Alaska: Seventeenth Ann. Kept. U. S. Geol. Survev. pt. 1, p. 807.
240 GBOGEAPHY AND GEOLOGY OP ALASKA.

conglomerates overlying the coal-hearing Kenai beds at Unga Island, but the writer 

did not find them at Kachemak Bay. They may occur farther inland, however.

"The shales of the Kenai formation on Kachemak Bay are all light-colored clay 

or mud rocks grading on one side into arenaceous shale and on the other into clay. 

They are soft and crumbly on the outcrop, and when wet become plastic. At the 

upper end of the bay they seem to be softer than at Bluff Point, which is a geologically lower horizon. Beds of day that have been baked by the burning of a coal 

seam are red and hard. Small blocks of gray, hard limestone were found at one 

locality, and suggest that the formation may contain a small amount of calcareous 

sediments, but no limestone was found in place."

The Kenai rocks of this region are little disturbed, and rest unconformably on 

both Jurassic and Triassic bods which are, much folded and faulted. Stone did not 

see the entire section of Kenai beds, but obtained measures showing 5,000 to 6,000 

feet of strata, and estimated that they may aggregate a thickness of 10,000 feet.

Probably the same horizon occurs on the west shore of Cook Inlet, at Tyonok, 

where there is an outcrop of fine feldspathic sandstone, with seams of impure 

lignite, or fossil wood, together with some fine conglomerate. These, together with 

some similar bods found in the Beluga, Skwentna, Keechatna, and Sushitna River 

basins, of the same region, may be Kenai, or may, as suggested by Spurr, represent 

a younger horizon, to which he gave the name Hayes" River beds. Spurr, 

however, assigned to the Kenai his Yentna beds, consisting of coarse conglomerates, 

apparently the same horizon as Eldridge's Kenai 6 on the Sushitna. The writer, 

who has examined some of these locations, is inclined to regard all the lignitebearing beds as synchronous deposits which may belong to the upper part of the 

Kenai, or may be of younger age, and 'thinks that their lithologic variations are 

due to their deposition in isolated basins.

Bituminous coal-bearing rocks carrying Eocene plants have recent^ been found 

in the Matanuska River Valley. These appear to be of the same character as those 

of Controller Bay.

On the Alaska Peninsula two distinct Eocene horizons have been recognized. 

The first is the widely distributed Kenai series, made of conglomerates, sandstones, 

and shales, and carrying plant'' remains. The second terrane includes a lower 

member, composed of breccias, agglomerates, and tuffs, and an upper member made 

up of shales, soft sandstones, and grits. Palache, rf who described these rocks, 

grouped them all together under the name Stepovak series. Marine fossils, 

assigned by Dall to the Middle Eocene, occur in some of the beds of the upper 

member. The Stepovak has not been recognized at any other locality, and its 

relation to the Kenai has not been established, but it is probably older.

Coal-bearing beds occur at a number of places and have been found in small, 

isolated areas along the eastern shore of the Alaska Peninsula and on the adjacent 

islands, and these Dall'' has correlated with the Kenai, some on definite paleontologic, but some only on general stratigraphic evidence. It is not impossible that

a Twentieth Ann. Rept. U. S. Geol. Survey, pt. 7, 1900, p. 172.

6Ibid., pp. 16 and 17.

c Knowlton, F. H., Fossil plants from Kukak Bay, Harriman Alaska Expedition, vol. 4, pp. 149-162, New York, 1904.

rfPalache, Charles, Geology about Ohichagof Cove, Stepovak Bay, Harriman Alaska Expedition, vol. 4, pp. 69-88.

^Seventeenth Ann. Rept. U. S. Geol. Survey, pt. 1, 1896. pp. 797-811.
EOCENE ROCKS. 241

some of these terranes may prove to be older than the Kenai, for at Chignik Bay 

the coal horizon is known to be of Cretaceous age. In the Aleutian Islands," as 

well as on the adjacent mainland, lignite-bearing beds have been reported, and 

referred to the Kenai.

The Wrangell volcanics occupy the most extensive area of any Tertiary rocks 

of the Copper River region, but though volcanism dominated during this epoch, 

some sediments were laid down during Kenai times, and could the extensive 

Pleistocene gravels be swept away, this horizon might be found to cover considerable areas. Mendenhall's Gakoua * formation includes a basal bed of conglomerate 

about 500 feet thick, shales, and beds of slightly indurated gravels and lignites, 

with Kenai plant remains. In the Tanana Valley, about 100 miles to the north, 

some soft, friable sandstone and fine conglomerate, called Tok sandstone,'* have 

been provisionally assigned to the Tertiary, and may be of Kenai age.

In the upper basin of the Cantwell River, a southerly tributarj- of the 

Tanana, the writer has found a well-defined series made up of a basal conglomerate 

several hundred feet in thickness, succeeded by at least 2,000 feet of reddish shales 

and sandstones. Some coal was found associated with the latter. These beds 

carry plant remains which Knowlton correlates with those of the Kenai. The 

rocks are, however, much more indurated and highly folded than the typical Kenai 

beds, but resemble the Eocene plant-bearing terranes of the Matanuska River 

Valley.

The Kenai was recognized in the Yukon Valley many years ago, but true stratigraphic relations have only recently been determined by the detailed studies of 

Collier and Hollick. The study of the material collected by them has not been 

completed, and but few of the results have been published. The paleobotanical 

investigations have fallen to Knowlton,'7 who has made the following preliminary 

statement of results to the Geological Society of Washing-ton:

"Up to about 1900 the known fossil flora of Alaska numbered about 110 

species, all of which has come from the coast region from Sitka to Cape Lisburne. 

With the exception of the Cape Lisburne forms, which were regarded as of JurassoCretaceous age, practically all those known were Tertiary in age. The discovery of 

gold in the interior incited exploration, and soon small collections of plants *were 

brought iu, mainly from the upper rocks of the Yukon. As these agreed in Tertiary 

age with those previously known from the coast region, it came to be accepted that 

only Tertiary plants occurred throughout this vast area. The United States Geological Survey desired to establish a type section, and in 1902 Mr. A. J. Collier was 

delegated to make a trip down the Yukon, studying the stratigraphy and collecting 

fossils from as many points as possible. When the plants were studied, it was found 

that those from above Rampart were Tertiary (so-called Arctic Miocene) while below 

this point a very different condition was found. Near Nahoclatilten Mr. Collier 

obtained collections which appeared to be mixed; that is, a part of the material

a Seventeenth Ann. Kept. U. S. Geol. Survey, pt. 1,1896, pp. 811-314.

b Mendenhall, W. 0., The geology of the central Copper River region: Prof. Paper 17. S. Geol. Survey No. 41. 

o Brooks, A. H., A reconnaissance in the Tanana and White river basins: Twentieth Ann. Kept. tT . S. Geol. Survey, pt. 

7. 1900, p. 473.

^Science, new series, vol. 19, 1904, pp. 738-784.
242 GEOGRAPHY AND GEOLOGY OF ALASKA.

seemed to be Tertiary and the remainder Middle or Lower Cretaceous. Undoubted 

Upper Cretaceous plants were obtained from a number of other localities, especially 

in the vicinity of Nulato, but so much interest attached to the Nahoclatilten localities 

that in 1903 Dr. Arthur Hollick was commissioned to duplicate Mr. Collier's trip. 

From the combination of the two collections it is possible to decide with certainty 

that all points above Rampart are Tertiary, while the plants below indicate that the 

age is either undoubted Cretaceous or doubtful Tertiary. The Cretaceous plants 

include cycads of several genera, conifers, and many dicotyledons, the combination 

resembling mostly the Middle and Upper Cretaceous flora of Bohemia.'"

It appears then that the Kenai of the Yukon falls into two geographic 

groups that of the upper river, which lies unconformably on various horizons, 

including Lower Cretaceous and older metamorphic rocks, and that of the lower 

river, which rests conformably on Upper Cretaceous beds. It occurs in a considerable area in Canadian territory near Dawson, and again a few miles below 

the boundary, as well as in many isolated patches in various parts'8 of the basin. 

In the upper river region it is typically made of heavy conglomerate, sandstone, 

and shale, with lignitic seams, may locally reach a thickness of several thousand feet, 

and is often closely folded and faulted. The Kenai of the lower river has about 

the same lithologic character, but the conglomerates and sandstones are usually 

finer, and the beds are but little disturbed.

Dall 6 provisionally assigned some coal-bearing sandstones and shales which 

are found between the Yukon and Norton Bay to the Kenai, but these may also 

prove to be of Upper Cretaceous age, as have some of those of the lower 

Yukon. A few lignite-bearing beds have been found in isolated patches in the 

Seward Peninsula and in the Kobuk Valley. These are usually but slightly 

indurated, consist essentially of feldspathic sandstone, and rest unconformably on 

the metamorphic rocks.

Sehrader has divided the Tertiary of northern Alaska into two formations/ 

which may be unconformable. The lower Colville is assigned to the Kenai, from 

the evidence of some fragmentary fossil plant remains, and from its position below 

beds carrying a Pliocene fauna. This horizon is about 150 feet thick, and consists 

essentially of partly consolidated silts, but its basal member is sandstone and shale, 

with lignite seams. There is little evidence of its extent, but it seems possible the 

same beds may be represented by the coal-bearing d horizon at Wainwright Inlet and 

Kuk River, which seems to be an entirely distinct occurrence from the coal horizon 

at Cape Lisburne.

MIOCENE AND PLIOCENE.

The reconnaissance work of the past few years has failed to show a wide distribution of Miocene or Pliocene beds in Alaska, for here little has been added to what 

Dall published ten years ago, except that Pliocene beds have been found in the 

Arctic slope province and some unconsolidated beds on the Yukon have been provisionally placed in one or the other of these epochs.

aCompare the coal resources of the Yukon, by Arthur J. Collier, Bull. U. S. Geol. Survey No. 218.

6Bull. U. S. Geol. Survey No. 184, p. 246.

"Prof. Paper U. S. Geol. Survey No. 20, 1904, pp. 81-83.

^Brooks, A. H., The coal resources of Alaska: Twenty-second Anu. Kept. U. S. Geol. Survey, pt. 3, 1901, p. 663.
MIOCENE AND PLIOCENE ROCKS. 243

The most southerly locality in Alaska where Miocene beds have been found is at 

Lituya Bay, where Dall a found sandstones and conglomerates which carry Miocene 

fossils. Spurr & reports the occurrence of sandstones, thin-bedded limestones, and 

shales at Icy Bay, 200 miles west of Lituya Bay. Fifty miles west, on Kayak 

Island, Martin" found Miocene conglomerates, sandstones, and shales.

Some marine fossils were found by Dall d in isolated localities along the coast 

of the Alaska Peninsula and on the adjacent islands, including the Aleutians, 

and were provisionally referred to the Astoria group (Miocene). On the north 

shore of Bristol Bay are some slightly consolidated gravels, sands, arkoses, and 

clays, which are somewhat deformed and were called Nushagak beds and referred 

to the Miocene by Spurr/ The evidence of their age rests on their stratigraphic 

relation to the Pleistocene, and to the fact that Miocene fossils had been reported 

from this vicinity by Dall.

In the Yukon basin the Nulato sandstone, formerly supposed to be Miocene, 

now finds place in the Upper Cretaceous. (See p. 286.) Spurr's-'' TwelvemiJe 

beds exposed on Mission Creek and assigned to the Pliocene are probably Kenai, 

but his Palisade ^ conglomerate, consisting of a cemented gravel, with some lignite, 

together with associated silts, is probably of Miocene or Pliocene age.

The Tertiary of the Arctic slope is divided by Schrader into two series, of 

which the lower is probably of Kenai age, while the upper carries marine fossils, 

probably of Pliocene age. This horizon, called Upper* Colville, is made up of 

fine gray calcareous silts, in which the bedding planes are entirely undisturbed, 

while the underlying Lower Colville is considerably deformed, suggesting an 

unconformity between the two formations. Sehrader states that the thickness of 

the Upper Colville is about 50 feet, and that the fossils came from near the top 

of the bed.

In considering the Miocene and Pliocene, the fact should not be lost sight of 

that some of the beds now classed with the Pleistocene may be older. In the 

Seward Peninsula the placer-mining operations have shown great local thickness of 

gravel deposits, and as little is known of the stratigraphic relations of the lower 

beds of these unconsolidated deposits it is by no means impossible that some of 

these may prove to be of Tertiary age, and if so will probably fall into the Pliocene.

SUMMARY OF TEKTIAKY STKATIGKAPHY.

The Kenai series, the oldest known Tertiary, has been referred to the Upper 

Eocene, but, as these are known to rest conformably on Upper Cretaceous, with 

which they form a continuous series without any stratigraphic break, it seems 

probable that the Kenai may include some Lower Eocene beds. The Kenai has 

been definitely recognized for nearly the entire length of the Yukon and at a number 

of localities in the Pacific coastal belt of Alaska. Its equivalent horizon in the

n Dall, W. H., Report on coal and lignite ol Alaska: Seventeenth Ann. Kept. U. S. Geol. Survey, pt. 1, 1896, pp. 783-784.

''Spurr, J. E., A reconnaissance in southwestern Alaska: Twentieth Ann. Kept. U. S. Geol. Survey, pt. 7, pp. 263-264.

( Martin, Q. C., The petroleum fields of the Pacific coast of Alaska: Bull. U. S. Qeol. Survey No. 250, p. 15.

rt Bull. U. S. Geol. Survey No. 84, pp. 252-259.

< Twentieth Ann. Kept. D. S. Qeol. Survey, pt. 7,1900, pp. 173-174.

/The Yukon gold district: Eighteenth Ann. Kept. D. S. Qeol. Survey, pt. 3,1898, pt. 196-197.

s Ibid., pp. 199-200.

A Prof. Paper U. S. Qeol. Survey No. 20, 1904, p. 83.
244 GEOGRAPHY AND GEOLOGY OF ALASKA.

Copper River basin is the Gakona formation, and in the Arctic slope region the 

lower Colviile series. It is usually characterized by conglomerates, sandstones, 

shales, and lignite seams, and the fossil plant remains show a fresh-water origin for 

most of these beds. One locality alone, and that on the Alaska Peninsula, has yielded 

marine Eocene fossils.

The Miocene is represented by some marine deposits which are found along the 

Pacific coast as far north as Bristol Bay. To the Pliocene have been assigned the 

upper Colviile, made up of silts, and, with less definite evidence, some cemented 

gravels on the Yukon.

QUATERNARY.

The Pleistocene and Recent terranes of this province are lithologically nearly 

identical, sometimes grading into each other, and geologic studies have in most cases 

not gone far enough to differentiate them. Therefore on the geologic maps (Pis. 

XX and XXI) the Quaternary is indicated as a stratigraphic unit. The Recent 

deposits, except the soil and ground ice, which are not mapped, cover relatively small 

areas, and the Quaternary of the map can be regarded as all Pleistocene except along 

the valleys, deltas, and seabeaches, where the younger sediments are included.

Much of the Pleistocene is directly or indirectly connected with the epoch of 

glaciation, and in a general way is divisible into the englacial deposits, which are the 

older, and extraglacial deposits, which are the younger. The englacial deposits 

include drifts, till, and a little morainic material, as well as other forms of washed 

gravel deposits; the extraglacial material is composed of the gravels, sands, and silts 

which were spread out as a mantle during the retreat of the ice. Though there are 

undoubtedly pre-Glacial Pleistocene deposits, the definite proof of their occurrence 

is still wanting. The Recent deposits are composed of fluvial and littoral sands, 

gravels, and silts of the present waterways, the ground ice, peat, muck, and soil, and 

the moraines of the existing glaciers, which are of relatively small import. In the 

following pages the present glaciers -will receive first consideration, to be followed 

by an account of the former glaciation, as well as of the materials which were 

deposited during the advance and retreat of the ice, and the section will be closed by 

a brief reference to the Recent deposits.

PRESENT GLACIERS.

In the popular mind Alaska is not infrequently associated with limitless expanses 

of snow and ice, but glaciers and permanent snow fields are almost entirely limited to 

the Pacific Mountain system. (Pis. XII and XXII.) The existing glaciers have been 

mentioned in the systematic geography, and further details can be found in Gilbert's" 

report, for only a few broader features of their occurrence will here be noted. 

Gilbert 6 states that glacial ice now covers 15,000 to 20,000 square miles distributed 

over about three-tenths of Alaska, and is found only in the Pacific Mountain system. 

(Pis. XII and XXII.) It seems probable that this latter statement needs slight modification, for Schrader" reports the small remnant of a glacier in the John River basin

a Gilbert, G. K., Glaciers: Harriman Alaska Expedition, vol. 3. New York, 1904.

t> Ibid., pp. 7-9.

« A reconnaissance in northern Alaska: Prof. Paper U. S. Geol. Survey No. 20, 1904, pp. 86 and 91.
U.S.GEOLOGICAL SURVEY PROFESSIONAL PAPER NO 45 PL XXII

178° 174° 170° 166- 162" ISfl" 154° 150° 146° 142° 138° 134" 130°' 122° 118"

in part above icr sli«et 

' during maximum " : ' :

gravpls.rlih'flyposl- X ,/ ! Direrlion ol'ii-t-inovcnicnl 

Olac'ial '

166° 154" "West of Greenwich ISO"

SKETCH MAP OF ALASKA SHOWING GLACIAL GEOLOGY

COMPILED BY ALFRED H .BROOKS 

Scale

JUUUS BIENftcO UTH N.v

1904
GLACIEKS. 245

of northern Alaska (PI. XXIV, £), and on the authority of prospectors larger 

glaciers in the higher mountains to the northeast. Lingering remnants of glacial ice 

are also to be found in the Kigluaik" Mountains of the Seward Peninsula, while 

Spurr* also reports a dying' glacier on the Ahklun Mountains near Bering Sea.

The large glaciers are on the seaward slope of the Pacific ranges, where they 

are fed by the extensive snow fields which find origin in the abundant precipitation 

from moisture-laden winds of the ocean. Many of the glaciers on the Pacific side 

reach far out from the mountains and some discharge directly into the sea, while 

those of the inland slopes are small and seldom reach the mountain fronts. (XXIII, 

A and _B). A rough measure of the relative intensity of the glacial-producing conditions between the coast and inland faces of the ranges may be had by comparing 

the general altitude of snow line and ice fronts. According to Hayes c the neve line 

of glaciers on the seaward slope of the St. Elias Kange has an altitude of 2,000 feet 

against 6,000 feet on the inland slope. Furthermore, while on the seaward side 

glaciers stretch into the sea, on the north side of the range they retreat rapidly at 

altitudes of 4,000 to 5,000 feet. A similar ratio of ice and snow line is found on 

the north and south slopes of the Wrangell Mountains, though here the altitudes on 

both sides are higher. On the south and east slope of the Alaska Range the snow 

line is between 4,500 and 5,000, and the ice fronts reach within 1,000 feet of sea level, 

while on the west and north slope the snow line is between 7,500 and 8,000 feet, and 

few of the glaciers reach even the front of the range, which stands at 2,500 feet.

FORMER GLACfATION.

The present glaciers of Alaska are but the remnants of far larger ice masses 

which mantled considerable areas but did not compare in extent with the former ice 

sheet of northeastern America, or even the present ice cap of Greenland. The accompanying map (PI. XXII) expresses the general features of the glacial geology, though 

few of the details are yet known.

Four areas were in comparatively recent times in part covered by glacial ice, and 

each of these had a more or less central source in highlands, which furnished the 

n£vo fields from which the ice flowed in directions determined, to a large measure, by 

the pre-Glacial topography. The glaciation of Alaska is to be regarded rather as an 

extension of the present system of alpine and piedmont glaciers than as a continental 

ice sheet. Each high range was the lociw of an accumulation of snow and ice, and 

from each radiated a distinct system of glaciers, which often did not leave the main 

lines of drainage. The present snow and ice fields of the St. Elias Range (Pis. XII 

and XXII), which fill the valleys and often no doubt cover divides and crest lines, 

and yet leave considerable areas not affected by ice, illustrate on a small scale the 

probable character of the former ice fields. The older glacial system was, howev7 er, 

far more extensive, and in southeastern Alaska approached the continental type.

On the map (PI. XXII) the mountains, which furnished the neVe fields and 

whose higher summits and crest lines towered above the snow and ice, are distinguished from the adjacent regions of lesser relief that were more completely

(i Reconnaissance of the Cape Nome and Adjacent Gold Fields of Seward Peninsula, Alaska, p. 43.

J'Spurr, J. E., A reconnaissance in southwestern Alaska: Twentieth Ann. Kept., U. S. Geol. Survey, pt. 7,1900, p. 253.

"Hayes, C. W., An expedition through the Yukon district: Nat. Geog. Mag., vol. 4, 1892, p. 153.
246 GEOGRAPHY AND GEOLOGY OF ALASKA.

covered by ice. Even in much of the regions of less relief the ice was confined 

to the valleys, and there were large uncovered areas. The lack of the detailed 

field observations and the small scale of the accompanying map has made it 

impossible to indicate the driftless areas within the glaciated region, about which 

some facts will be presented.

The advance and retreat of these ice sheets were probably, broadly speaking, 

synchronous throughout the province with the movements of the oordilleran 

glacier to the south. During the retreat the flood of waters, caused by the 

melting of the ice, carried a large amount of gravels, sands, and silts, which was 

deposited in broad mantles. There are now found in the gravel piedmont plateaus, 

and in the terraces, remnants of these deposits which are such prominent features 

of Alaska topography. This epoch of ice invasion from the highlands to the 

lowlands is of comparatively recent date, for the remnants of the larger ice sheet 

are still preserved in the many glaciers of the Pacific ranges of Alaska, and 

Pleistocene fossils are found in the overwash deposits.

The glacial geology is known only in its broader aspects, for no detailed 

mapping of these Pleistocene terraces has been carried on, but it is probable 

that the ice movements were not simply as have been outlined, but included a 

number of advances and retreats.

The great cordilleran ice sheet of northwestern America, which, according to 

Dawson," swept north and south from its source in British Columbia, probably 

only reached into southeastern Alaska, where it passed through the Coast Range 

gaps, and, uniting with the local glaciers from these mountains, helped to scour 

out the extensive system of waterways of the Pacific shore and covered a good 

part of the Alexander Archipelago. The evidence of glacial erosion in this 

southeastern province indicates a great thickness of ice, and here, unlike other 

parts of Alaska, the ice overrode considerable altitudes. The large unmapped 

areas in the islands make it impossible to indicate the limits of the ice sheet, but 

it probably covered most of the archipelago and dumped its de'bris directly into 

the Pacific beyond. It is certain, in any event, that the larger channels, such as 

Chatham Strait and Lynn Canal, were occupied by glaciers (PI. IV, A).

The northern front of the cordilleran ice* sheet formed a very irregular line 

extending northeast from the White River across the Yukon basin to the Rocky 

Mountains, for along the valleys of the larger river the ice extended north far 

beyond the general front as great tongues (map, PL XXII). It is probable that 

detailed studies may show even a still greater irregularity of ice front, for the 

glacial limit has been chiefly determined by journeys along the water courses, and 

it may be found that many of the interstream areas were never covered by the 

ice. Almost throughout this northern ice limit there is a striking absence of

anawson, G. M., On the later physiographical geology of the Rocky Mountain region in Canada: Trans. Roy. Soc. 

Canada, vol. 8, sec. 4,1890.

fcDawson, G. M., Exploration in the Yukon district: Geol. Nat. Hist. Survey Canada, vol. 3, pt. 1., 1889; Report on the 

later physiographical geology in the Rocky Mountain region of Canada: Trans. Roy. Soc. Canada, vol. 8, sec. 4,1890.

Russell, I.e., Notes on surface geology of Alaska: Bull. Geol. Soc. America, vol. 1, 1889, pp. 99-154.

Hayes, C. W., An expedition through the Yukon district: Nat. Geog. Mag., vol. 4,1892, pp. 117-162.

Tyrrell, J. B., Glacial phenomena in the Canadian Yukon district: Bull. Geol. Soc. America, vol. 10, 1898, pp. 193-198.

Brooks, A. H., A reconnaissance in the White and Tanana river basins: Twentieth Ann. Rept., TJ. S. Geol. Survey, 

pt. 7,1900, pp. 429-494; Keconnaiaance from Pyramid Harbor to Eagle City: Twenty-first Ann. Rept. TJ. S. Geol. Survey, pt. 

2, 1900, pp. 331-391.
U, S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 45 PL. XXIII

A. OCONNOR GLACIER FROM SLIMS RIVER VALLEY. 

A typical valley glacier on the north slope of the St. Elias Range.

B DALTON GLACIER, DISENCHANTMENT BAY. 

A typical tide-water glacier from south slope of St. Elias Range.
GLACIERS. 247

moraiiHc material, indicating the presence of a system of valley glaciers whose 

dumping ground was soon removed by the floods which accompanied the retreat.

The Pacific Mountains to the north had several centers of glaciatiou. The 

St. Ellas Range sent one ice sheet northward, which probably united with the 

cordilleran glacier and another one southward which discharged into the Pacific.

Schrader and Spencer" have shown that all three of the ranges which bound 

the Copper River basin and plateau were feci for the accumulation of ice which 

eventually overrode the entire basin, and that the Chugach Mountains on the 

south poured down their seaward slope great masses of glacial ice which scoured 

out the iiords of Prince William Sound.

The Alaska Range to the northwest also contributed glacial ice which moved 

southward across the Copper River Plateau and down the Sushitna Valley and 

filled, in part at least, the upper end of Cook Inlet. On the north and west of 

the same range the glaciers stretched well out into the lowland of the upper 

Kuskokwim. In these mountains the upper limits of glaciation is between 4,000 

and 5,000 feet.

During this epoch both slopes of the Aleutian Range were the breeding 

grounds of glaciers which discharged into the sea; their scouring helped to 

produce the irregularities of shore lino of the Alaska Peninsula.

The higher valleys of the Ahklun Mountains near Bering Sea are U-shaped, 

and there is other evidence of their having been occupied by glaciers,* but this 

ice accurnmulation was evidently very local.

Throughout most of the interior plateau province glaciation was limited to the 

margin, but in the Seward c Peninsula the Kigluaik and Bendeleben mountains were 

the sources of comparatively small valley glaciers, some of which reached the sea.

The mountains of northern Alaska are less well known, but it is certain that 

their higher parts were the loci of ice accumulation, which stretched out from the 

base of both slopes. Schrader d found that this ice extended southward along some 

of the valleys nearly 50 miles from the base of the range. In the John (PI. XXIV, 

A and B) and Chandlar valleys he noted the presence of till to a depth of 100 feet, 

but these glaciers, like those of the Pacific Mountains, seem to have left but little 

morainic material. The upper limit of this valley system of glaciers is between 

2,500 and 3,500 feet.

On the north side of the Rocky Mountains, where the fall-off to the lowland is 

more abrupt (PI. XXIX, B) and the climatic conditions were probably more 

favorable, the ice seems to have accumulated over a larger area, and probably had a 

fairly well-defined front 30 to 40 miles from the base of the mountains, while long 

tongues extended still farther north along the larger river valleys. Evidence of 

glaciation has been found up to an altitude of 3,000 to 4,000 feet, near the Arctic 

front of the mountains. The mountains to the east are almost unexplored, but there 

is no reason to believe that they are any less glaciated.

uSehrader, F. C., and Spencer, A. C., The geology :,nd mineral resources of a portion oi the Copper River district 

pp. 76-79.

f'Spurr, J. E., A reconnaissance in southwestern Alaska: Twentieth Ann. Kept. U. S. Geol. Survey, pt. 7, 1900, 

pp. 253-254.

c Brooks. A. H., Reconnaissance of Nome and Adjacent Gold Fields, pp.

d Prof. Paper U. 8. Geol. Survey No. 20, 1904, pp. 84-94.
248 GEOGRAPHY AND GEOLOGY OF ALASKA.

Mendenhall found evidence of valley glaciation to the west of Schrader's route 

of travel, and ascribes a glacial" origin to several of the lakes which are tributary to 

the head of the Kobuk, and is inclined to the belief that in,the mountains between 

the Kobuk and the Noatak was an accumulation of glacial ice which spread out into 

the valleys from both slopes.

On the glacial map these fragmentary data have been generalized, and considerable 

areas have been included in the glacial limits. The map should not be interpreted 

as indicating the presence of an ice cap comparable to that of southeastern Alaska, 

but rather as showing an area in which there was an extensive development of alpine 

and piedmont glaciers.

PLEISTOCENE SEDIMENTS.

The Alaska Pleistocene, as a rule, has not been differentiated into distinct horizons, and it is not possible to give detailed descriptions. The deposits near the 

limits of glaoiation are characteristically heavy beds of gravels and sands, which are 

cross-bedded and present every indication of having been fluvial deposits in swift 

water. Away from the source of the material the deposits become gradually finer, 

eventually grading into fine silts, with horizontal bedding and every evidence of 

sluggish water deposition (PI. XXV, £). A good example was observed at 

the northern base of the Alaska Range, in the valley of the Cantwell River, where a 

coarse gravel and sand deposit, aggregating probably 800 feet in thickness, mantles 

the base of the range. These terranes, which have a very perceptible dip away 

from the mountains, and probably represent an initial plain of deposition, rapidly 

decrease in thickness and merge gradually into finer deposits; and finally, 50 miles 

away, are replaced by fine silt deposits less than 100 feet thick. It appears as if 

'Schrader's 6 Goobic sand, which mantles the upper Tertiary beds north of the limit 

of glaciation in the Arctic slope province, may have a similar history. These latter 

are of fine sands with some silts and an occasional layer of gravel, and appear to 

resemble closely the Pleistocene silts of the Yukon Valley.

Fine silt deposits occur throughout the length of the Yukon and on many of 

its tributaries and are typically buff colored, with a thickness of 50 to 200 feet, and 

often rest on a layer of gravel (PI. XXV, J2). On the upper Lewes these silts 

overlie glacial till, showing them to have been deposited after the retreat of the ice. 

The large bowlders occurring in the silt must have been ice borne, suggesting 

deposition during the floods which accompanied the retreat of the ice. Spurr, c who 

described the Recent deposits of the Yukon Valley in considerable detail, grouped 

all of the fine material together under the name Yukon silts. It appears that he 

has included in this formation not only the sediments which accumulated during the 

post-Glacial floods, but also the recent alluvium of the present rivers, and it seems 

desirable to limit the formation to include only the older silt deposits. He 

suggested that these silts were deposited in lake basins, but this hypothesis seems 

to be only locally applicable. He also discusses a number of other theories d

a Mendenhall, W. C,, A Reconnaissance from Fort Hamlin to Kotzebue Sound: Prof. Paper U. S. Geol. Survey No. 

10, 1902, pp. 45-48.

!>Prof. Paper U. S. Geol. Survey No. 20, 1904, p. 93.

c Geology of the Yukon gold district: Eighteenth Ann. Kept., U. S. Geol. Survey, pt. 3, 1898, pp. 200-221.

<ilbi<3., p. 222.
IGNEOUS ROCKS. , 249

advanced by various writers as to their origin. These will not be discussed here, as 

it appears desirable to obtain more facts in regard to the occurrence of the silts 

before speculating further on their genesis. At a number of localities these silts 

have yielded both vertebrate and invertebrate Pleistocene fossils.

In most of the Alaska geologic reports mention is made of widely distributed 

sands and gravels, but as it is yet impossible to establish any system of correlation 

between them they will here be passed over in a few words. A marine bench has 

been found by Spencer at about 200 feet above sea level near Juneau, in southeastern Alaska, and Russell found Pleistocene marine fossils in unconsolidated 

material 5,000 feet above sea level on the southern slope of St. Elias. Extensive 

gravel benches occur around the head of Cook Inlet, 100 to 300 feet above sea level, 

while high glacial benches are found on both sides of the Alaska Range, and similar 

features are present in the Aleutian Range. The great Copper River basin is 

filled to depths of several hundred feet by silts and sands, with some gravel, up to 

an altitude of about 3,000 feet (PI. XXV, A). In the Yukon basin, ancient 

stream gravels are found to an altitude of several hundred feet above the present 

water courses. The Seward Peninsula has well-marked fluvial and marine benches 

up to an altitude of 800 or 1,000 feet, and some less well-marked features have been 

observed at still higher altitudes (PI. XXX, A). All these facts have bearing on 

the recent orographic movements in the province and will be referred to again in 

the discussion of the geomorphology.

RECENT DEPOSITS.

The distribution and origin of the ground ice, which is found in all parts of 

the Territory north of the Pacific coastal belt, is an important but unsolved problem. While it has been supposed to form a practically 'continuous layer below 

the thick coating of moss, such has not been found to be the case. In the Seward Peninsula, where the mining operations have pierced the surface coating at 

many places, the ground ice has not by any means been universally met with, 

for though in places it extends to the extreme depth of excavation of 100 to 150 

feet, in other localities near-by it is often entirely wanting.

IGNEOUS ROCKS. 

INTRUSIVES.

References have been made in the foregoing pages to the igneous rocks which 

are associated with the various sedimentary horizons. It seems worth while to 

briefly summarize these facts, though it is beyond the scope of this paper either 

to enumerate the many rock types which have been reported or to discuss the 

petrography of this province.

The so-called Archean gneisses are partly made up of altered igneous rocks, 

and dikes and stocks of massive acidic and basic rocks are not uncommon in the 

gneissic areas. These could not be shown on the map (PL XXI) because it is 

impossible with the meager data at hand to draw boundaries between the massive 

igneous rocks and the gneisses.
250 GEOGRAPHY AND GEOLOGY OF ALASKA.

In the metamorphie rocks, including- the undifferentiated Paleozoic, stocks, 

dikes, and sills are almost equally common. These intrusives are of varied types, 

though chiefly acidic, and belong to different periods of injection, for some have 

been rendered quite schistose, while others are entirely massive. Intrusives occur 

in the Devonian and Carboniferous, though here they are less prominent than in 

the older terranes. Schrader's researches have brought out the important fact 

that intrusives are apparently entirely absent from the Paleozoic terranes of the 

northern axis of the Rockv Mountains.

The largest intrusions took place probably during Jurassic times, when the 

great granite and granodiorite batholith was injected, which is traceable as an almost 

unbroken mass from southern British Columbia into Alaska, a distance of over a 

thousand miles. Beyond the point where the granite ceases to occur in continuous 

outcrops the same period of injection seems to maintain itself to the west and 

southwest by a series of large granodiorite stocks which occur along the axis of the 

Alaska Range. In the same range are dikes of more basic rocks, which seem to 

belong to a later dynamic revolution. Another large granitic intrusion is exposed 

in a belt along the axis of the Alaska Peninsula. Granite stocks and dikes are also 

not uncommon in the Cretaceous rocks of the Kuskokwim Valley. In the Seward 

Peninsula are many stocks of granitic rocks which are entirely massive. Basic dikes 

of later age have been found in the Eocene beds of the Yukon.

VOLCANICS.

Though petrographic work may reveal effusives among the metamorphic rocks 

of the older terranes, up to the present they have not been definitely recognized 

below the Devonian.

The Rampart series (Devonian) of the Yukon-Tanana region includes a great 

thickness of volcanic rocks, chiefly of a basic character. The pre-Permian Nikolai 

greenstone of the Copper River region is entirely composed of a succession of 

basaltic flows. The greenstones of the Permian beds of southeastern Alaska are 

known to be in part of volcanic origin. The same horizon in the Copper basin, 

called the Mankomen group, contains a large amount of effusive material.

As Mesozoic extrnsives can be counted the Kasaan greenstone (?) of the Prince 

of Wales Island and the extensive Triassic, Jurassic, and Cretaceous volcanics of 

the Alaska Peninsula. In all these extrusives andesitic rocks are the prevalent type.

Little has been learned of these older volcanic phenomena, but the history of 

more recent volcanic activity is somewhat better known. Since early Tertiary times 

volcanism has been active in the Copper River basin and probably in the Alaska 

Peninsula, and in both districts it still persists in the present volcanoes. Here, too, 

andesite is the most abundant type, but basalts are not uncommon.

In the Wrangell region an extensive mountain group has been built up entirety 

of extrusive material, chiefly andesitic, and the limit of distribution of the volcanics 

is well marked by lowlands surrounding the mountains on all sides except on the 

south, where they are coextensive with the unexplored part of the St. Elias Range.

The Aleutian volcanics, in which, as far as known, andesites dominate, can 

probably be regarded as a southwestern extension of the same zone, though they 

are not geographically connected with the Wrangell Mountains. The Aleutian

&
U. S. GEOLOGICAL SURVEV PROFESSIONAL PAPER NO. 45 PL. XXIV

A. GLACIATION IN UPPER JOHN RIVER VALLEY, ENDICOTT MOUNTAINS, 

Looking S. 25° W.

£. ICE REMNANT OF JOHN RIVER VALLEY GLACIER IN ENDICOTT MOUNTAINS.

Looking southwest.
U. 8. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 46 PL. XXV

A. EASTERN MARGIN COPPER RIVER PLATEAU. 

Showing silt deposits.

£, LEWES VALLEY AT WHITE HORSE. 

Showing silt terraces.
U. 8. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 45 PL. XXVI

WHITE HORSE RAPIDS OF THE LEWES. 

Caused by recent lava flow.

B. MILES CANYON, LEWES RIVER, CUT IN RECENT LAVA FLOW
U. 8. GEOLOGICAL SURVEV

Longitude 1M' ~Vfea. from____1ST_____Greenwich 150' IS*" ISO100 1 00 2QO 3QO 4QO miles

MAP SHOWING METEOROLOGIC STATIONS.
PROFESSIONAL PAPER NO. 45 PL. XVIII

400 miles

 1C STATIONS.
IGNEOUS KOCKS. 251

Range, forming the backbone of the Alaska Peninsula, consists of a series of 

volcanic cones scattered on a northeast-southwest axis. Liko the Wrangell volcanics, many of them are still more or less active, probably a survival of the more 

intense volcanism of Tertiary-Mesozoic times.

Mount Edgecumbe, which lies a few miles northwest of Sitka, is the only 

volcano known in southeastern Alaska. According to F. E. Wright, basic andesite 

is the prevalent rock type. This mountain seems to mark the southern termination of that broken zone of volcanoes which lies on a crescentic axis, on one 

arm of which are the Wrangell volcanoes, and on the other those of the Alaska 

Peninsula and the Aleutian Islands. Its western end lies near Kamchatka, and 

may have some connection with the volcanoes of that isthmus.

The inland and northern regions of Alaska are marked by au absence of 

volcanoes, but evidence of volcanism is not entirely lacking, for throughout the 

Yukon basin and in the Soward Peninsula small areas of Pleistocene or Recent 

volcanic flows are not uncommon. Some of these have been extruded so recently 

that they have affected the present drainage system (PI. XXVI, A and /?). The 

distribution of the larger of these areas is indicated on the accompanying map 

(PI. XXI), and it will be noted that none of them has yet been found in the 

northern Rockies, where, as has already been indicated, intrusive rocks are also 

absent. These recent outpourings of lava are especially noticeable in the Bering 

Sea littoral, for nearly all the islands of the sea arc, made up largely of these 

volcanic rocks. Among these recent extrusions basaltic rocks appear to dominate.

One other phase of volcanic activity deserves mention; that is the extensive 

deposit of volcanic " tufa of the upper White River basin, in many places 

entirely bare or overlain by only a few inches of soil. This tufa is of andesitic 

character and seems to have been ejected from a vent lying in the St. Elias 

Range near the international boundary. It has been traced northward as far as 

Fortymile River, westward to about the one hundred and forty-second meridian, 

and northeastward to near latitude 62° 30'. It covers an area of about 90,000 

square miles. Near its outward margin the layer of tufa is only a fraction of 

an inch in thickness, whereas near its source in the White River basin it is 

found in drifts upward of 100 feet deep. This volcanic deposit is the only one 

of the district which appears to have had an explosive origin.

SUMMARY OF STRATIGRAPHIC SUCCESSION.

The Pelly gneisses form the basal complex of the province. They are made 

of crystalline rocks, believed to be of Archean age, occur in but small areas, and 

their relations to sedimentary beds are not definitely determined. The oldest 

sediments include a great thickness of phyllites and related elastics, succeeded

aSchwatka, Frederick, Along Alaska's great river: New York, 1SX8, p. 196.

Dawson, G. M., An exploration in British Columbia and Northwest Territory: Ann. Rept. Geol. Nat. Hist. Survey 

Canada., new series, vol. 3. pt. 1, 1889. pp. 43B-46B.

Russell, I. 0., Notes on the surface geology of Alaska: Bull. Geol. Soc. America, vol. 1, 1899, p. 145.

Hayes, C. W., An expedition through the Yukon district: Nat. Geol. Mag., vol. 4, 1892, p. 146.

Spurr, J. E., Geology of the Yukon gold district: Eighteenth Ann. Rept. U. S. GeoL Survey, pt. 3, 1898, p. 223.

Brooks, A. H., A reconnaissance in the White and Tanana river basins: Twentieth Ann. Rept. U. S. Geol. Survey, 

pt. 7, 1900, p. 475: Reconnaissance from Pyramid Harbor to Eagle City: Twenty-first Ann. Rept. U. S. Geol. Survey, 

pt. 2, 1900, pp. 365-366.

17211 No. 45 06 17
252 GEOGRAPHY AND GEOLOGY OF ALASKA.

bv calcareous deposits which in places carry Silurian fossils, the oldest organic 

remains, except a few Ordovician which have been found in Alaska. This extensive 

limestone horizon, usually highly altered, is provisionally referred to Silurian, 

but has yielded fossils at only a few localities. Though some of these limestones 

may prove to be of different age, it seems to be probable that there is in Alaska 

a Silurian horizon, represented by heavy limestones, which has a very wide 

distribution and which is underlain by a great series of argillaceous and arenaceous 

rocks, which are here assigned to the Paleozoic, though they may be in part 

pre-Cambrian.

The Devonian, which is probably everywhere separated from older terranes 

by an unconformity, includes a heavy conglomerate, also shales and limestones, 

and, in part of the territory, extensive masses of igneous rocks.

Of the Carboniferous divisions, the Permian is best represented, but some 

heavy limestones have been found which are referred to a lower horizon in the 

system. The Permian beds include limestones and slates, and, in the Copper 

River basin, where this series reaches a thickness of 6,000 to 7,000 feet, 

considerable volcanic material. There is evidence of local unconformities between 

the Carboniferous and Devonian, but a wide-reaching erosional interval has not 

been established.

Triassic fossils have been found in the Copper River basin and on the 

Alaska Peninsula in limestones and shales. In the same districts, as well as in 

northern Alaska, Jurassic beds of diverse composition, aggregating many thousand feet in thickness, have been found. The Jura-Cretaceous is represented 

nearly throughout the province, usually as a limestone and shale series, but 

often carrying sandstones and conglomerates. It rests unconformably on the 

older horizons.

Both Lower and Upper Cretaceous rocks, usually limestones and shales, occur 

on the lower Yukon basin and in northern Alaska. Upper Cretaceous beds have 

been found in the Alaska Peninsula and in southeastern Alaska. The Kenai, 

the oldest member of the Tertiary, typically a fresh-water deposit, including 

conglomerates, sandstones, and shales, with lignite seams, is very widely distributed. Some marine Eocene beds have been found on the Alaska Peninsula. 

Miocene, including sandstones, limestones, and shales, has been found along the 

southern base of the St. Elias Range in southwestern Alaska. Pliocene beds 

have been reported at some localities, but appear to have a very limited development. The Pleistocene is represented by deposits of glacial origin in the two 

mountain systems, and by more extensive terranes, including unconsolidated 

gravels, sands, and silts throughout the territory. The glaciation, except in 

southeastern Alaska, must be considered due to a former wider extension of the 

present alpine and piedmont glaciers rather than to a general ice sheet.

STRUCTURE.

INTRODUCTION.

References to structure have, as far as possible, been omitted from the preceding 

discussion for the sake of presenting a clearer conception of the stratigraphic sequence 

by disregarding the complexities introduced by deformation. This arrangement,
STRUCTURE OF PACIFIC MOUNTAIN SYSTEM. 253

however, involves a certain amount of repetition. As it seems desirable to avoid 

constant use of qualifying phrases, the geologic sequence, already fully discussed, 

will be regarded as definitely established. It will also not be deemed necessary to 

cite all authorities to which full references have already been made.

There will here be no attempt to indicate more than the barest outline of the 

larger structural features, and the following pages will be largely devoted to a 

discussion of nine geologic cross sections (see PI. XXVII) of various parts of the 

province. The location of these sections has of necessity been determined by the 

districts which have been investigated rather than by those which might be expected 

to elucidate the dynamic history. For example, there are no data upon which a 

section through the St. Elias Range can be constructed, though this would form the 

key to the relation of the structural features of southeastern Alaska to those of the 

Copper River region.

A few of the dominant structural axes are indicated on the geologic map (PL 

XXI), but these must be regarded as largely hypothetical. They represent chiefly 

the results of the deformation during Mesozoic times, for the older structural axes 

are not well known, and the Tertiary and later crustal movements were rather of the 

character of broad uplifts and depressions than of plications. That some of these 

later disturbances were accompanied by important deformations is indicated by the 

close folding and faulting of some of the Eocene beds, but these seem to have been 

rather local in their effect.

The general trend of the structural lines parallel to the coast and to the mountain 

systems has been repeatedly dwelt upon. All of the dominant structures in southeastern Alaska strike northwest; following the coast they swing gradually to the 

west, and near the one hundred and fiftieth meridian turn southwest and continue in 

this same general direction to the Bering Sea. Most of the important lines of 

deformation throughout the province are parallel to these structures.

STRUCTURE OF PACIFIC MOUNTAIN SYSTEM.

Though the axes of the four great ranges of the Pacific Mountain system have a 

marked parallelism, their geologic history has been by no means uniform. The 

rocks of the Coast Range are igneous, intruded as a great batholitic mass, while the 

St. Elias Range proper seems .to be built up of complexly folded sedimentaries, 

probably chiefly Paleozoic, together with many intrusives. The component strata of 

the Chugach and Nutzotin mountains, the two main forks of the St. Elias Range, are 

closely folded sediments (Mesozoic?), while the Wrangell Mountains consist of great 

series of Recent and Tertiary volcanics resting on the beveled edges of folded Mesozoic beds. In the Alaska Range, Mesozoic and Paleozoic terranes are found closely 

infolded as a great synclinorium, interspersed by large stocks of granodiorite. The 

Aleutian Range is formed of a series of volcanoes and their ejecta, resting on folded 

Mesozoic strata and Tertiary sediments.

In southeastern Alaska there is a complex of metamorphic sediments, ranging 

in age from Silurian or older to Permian and possibly Triassic, and bounded on 

the east by the intrusives of the Coast Range. In some places these metamorphics 

are mantled by less altered and less deformed sediments, in part Tertiary (Eocene)
254 GEOGRAPHY AND GEOLOGY OF ALASKA.

and in part assigned to the Mesozoic. The metamorphic sediments, usually 

intensely plicated, have a general northwest strike and steep westerly dips. The 

oldest of these terranes are believed to lie in a belt which extends southward from 

Glacier Bay through the western part of the Alexander Archipelago to Dixon 

Entrance. The general structural relations in this district are illustrated in the 

section AA (PL XXVII), which is drawn at right angles to the strike from Prince 

of Wales Island eastward, through the Ketchikan region, traversing the Coast 

Range, and extending into British Columbia. The closely folded limestones and 

phyllites of the Wales series, together with some intrusives, are shown at the 

western end of the section. Though the dips of these beds are concentric the 

structure is probably anticlinal and fan shaped. The Wales rocks are supposed 

to be Silurian and hence older than the Vallenar series (Devonian), which lie to 

the east and apparently dip underneath them. The Mesozoic (?) volcanics (Kasaan 

greenstone) rest horizontally on the beveled edge of the Vallenar beds.

The Ketchikan schists, made up of argillites and greenstones, with some 

limestones, separate the Devonian rocks from the Coast Range intrusives to the 

east, and are probably in part Carboniferous in age. The schists all dip westerly 

at high angles, and, as the oldest beds are on the west, indicate an anticline overturned toward the east. To the east the Ketchikan schists become more highly 

crystalline, are broken by granite masses, which are injected parallel to the bedding, and finally give way to a broad belt of the Coast Range intrusives 30 to 40 

miles in width, which probably consists entirely of massive rocks, though it has 

not been explored throughout. Metamorphosed Paleozoics bound the igneous rocks 

on the east and are unconf orrnably overlain by less highly folded Mesozoic beds.

Though prevalent^ the dips are westerly, suggesting a monocline, the age 

determinations indicate that the oldest horizons are on the west, and therefore 

there has been an overturn to the east. There is also a suggestion of an anticlinal 

axis along the medial line of Prince of Wales Island, though this is largely 

hypothetical. It also seems quite probable that there may be duplication in beds 

in the Ketchikan series, and that these are 'made up of a succession of closed 

folds overturned to the west. The tnctamorphic sediments which lie adjacent to 

the Coast Range intrusives on the east are of undetermined age, and furnish no 

clew to the structures.

As the post-Triassic Mesozoic beds of this section are com para tively little 

deformed, the, extensive dynamic revolution must have taken place before their 

deposition. There can be little doubt that the major structures are the result of 

more than one period of deformation. The Coast Range batholith was probably 

injected in late Jurassic times.

The same general geologic features are shown in the section BB (PI. XXVII), 

which is constructed on rather fragmentary a data, and extends from Sitka through 

Juneau and across the Coast Range into British Columbia. As in* the southern 

section, the metamorphic sediments have the same westerly monoclinal dip, but 

the evidence here also points to an anticline overturned to the west. The closely 

folded limestones and phyllites of Admiralty Island, provisionally correlated with 

the Wales series to the south, are believed to be identical with those of Glacier

j Wright has recently made a detailed ptudy of this section, but his results are not yet available.
STRUCTURE OF PACIFIC MOUNTAIN SYSTEM. 255

Bay to the north, which carry Silurian fossils. Though a Devonian fossil has 

been found in this district, no well-defined group of rocks has been mapped which 

can be correlated with the Vallenar series. The equivalents of the Ketchikan 

.schists are found in the raetamorphic rocks exposed near Juneau, with which the 

Ketchikan schists have a close lithologic similarity, and which have yielded a few 

ill-defined organic remains which are probably Permian. The Coast Range intrusives have the same character in both sections, between which they have been 

continuously traced. In the Juneau section (BB) are some flat Eocene beds 

resting on the upturned edges of the older rocks, and on Admiralty Island another 

group of sediments rest unconformably on the older rocks and have yielded 

Jura-Cretaceous fossils.

The two sections AA and BB, nearly 400 miles apart along the strike, show 

enough similarity to make it probable that the general geologic features of the 

intervening belt are much the same. What appears to be a closely folded 

anticline overturned toward the mainland brings up Silurian rocks in the westernmost of the islands of the Alexander Archipelago, east of which is a belt of 

limestones (Devonian), which give way still farther east to phyllites and schists of 

Carboniferous and possibly Triassic age. All of these groups of strata probably 

include some duplication by folding or faulting, and all are overturned to the 

east. A broad belt of granodioritic rocks, which crosses diagonally the strike of 

the, sediments to the east of the schists, separates them from another belt of 

Paleozoics. At several localities little-disturbed Mesozoic and Tertiary beds are 

found resting on the upturned edges of the metamorphic sediments.

The strike of the Silurian limestones and phyllites at Glacier Bay would carry 

them into the heart of the St. Elias Range, but little is known of the component 

strata of this great mountain mass. Mesozoic and Tertiary beds have been found 

along its southern flank, and metamorphic terranes are known to occur toward 

its center, while a fairly well-defined belt of Permian strata has been traced along 

its inland front. Mount St. Elias itself is known to consist of a great intrusive 

mass of dioritic rock, which may likely belong to the same period of injection as 

that of the Coast Range. These fragmentary data and the topographic continuity 

suggest that the general sequence and structures of southeastern Alaska and the 

St. Elias Range may be the same.

In the Copper River basin the succession and structure are so different from 

those to the south that it is hopeless to yet attempt correlations. It has been 

shown that west of the one hundred and forty-first meridian the mountains appear 

to break into three distinct ranges the Chugach along the coast, the Wrangell, 

forming the central mass, and the Scolai or Nutzotiri Mountains, constituting 

the inland limit of the system. The section CC, from Controller Bay to the 

Tanana Valley, is an expression of the general structural features of the three 

highland masses. A comparison of this with the Juneau section (BB) indicates 

the futility of correlating between the two districts unti1 the intervening area 

has been examined.

Sandstones and shales, probably Mesozoic, closely folded and faulted, but with 

a general westerly dip, are represented at the western end of the section. These 

are underlain on the east by the closely folded gravwacke, slates, and phyllites of
256 GEOGRAPHY AND GEOLOGY OF ALASKA.

the Valdez series, which go to make up the Chugach Mountains of unknown age, 

but here provisionally assigned to the Mesozoic. On the north the Valdez rests 

probably uncomformably on the crystalline limestones and schists, provisionally 

referred to the Paleozoic, under the name Kluttna series. The Valdez rocks are 

thrown up into a series of folds, indicated diagrammatical ly on the section.

A strong contrast between the geology on the north and that on the south side 

of the Chitina Valley suggests faulting, for on both walls the strata dip away from 

the axis and appear to be of different ages. North of the Chitina the Nikolai greenstone, a succession of lava flows, forms the basal member, and is overlain by the 

Chitistone limestone (Permian ?), on which rest conformably several thousand feet 

of Triassic shales, which are succeeded unconformably by the Kennicott series, of 

Jura-Cretaceotis age. The higher parts of the Wrangell Mountains are made up 

entirely of a great complex of Recent and Tertiary lavas, which on the southwest lie 

unconformably on the Kennicott series and on the northeast are in contact with 

shales which can probably be referred to the Triassic or Jura-Cretaceous. These 

shales of the northeastern slope are in turn underlain by Permian limestones, which 

also dip to the southwest.

This Permian limestone seems to be separated by faulting from the closely 

folded graywackes, limestones, and slates (Mesozoic) which make up the component 

strata of the Nutzotin Mountains. This fault separates the southerly dipping Permian limestone at the base of the Wrangell Mountains from the northerly dipping 

Nutzotin rocks (Mesozoic?), which comprise a closely folded series, ending in the 

north at the alluvial-floored Tanana Valley, beyond which the section shows westerly dipping metamorphic sediments (Tanana schists) resting on a gneissic complex 

(Archean?).

The beds of the Wrangell Mountains seem to lie in a syncline bounded on both 

sides by faults which have broken the adjacent anticlines and beyond which are 

broad synclinoriums of Mesozoic beds. The central syncline of the Wrangell 

Mountains is then faulted on both margins and forms an uplifted block. On the 

west the Wrangell Mountains break off to the alluvium-filled Copper River basin 

and afford no further clew to the structure.

The succession of dynamic events in this district is perhaps as follows: The 

supposed lower Paleozoics were probably deformed and metamorphosed at some 

time previous to deposition of the Permian. After Triassic beds had been laid down 

another crustal movement took place, followed by erosion and the accumulation 

of the Jura-Cretaceous sediments. These latter were then thrown up into the 

broad syncline of the Wrangell Mountains, which was at the same time blocked 

out by faulting along both arms. The later crustal movements seem to have been 

not sufficiently localized to bring about any considerable deformations.

The structure of the Chugach Mountains is still more uncertain, for its extension lies in the ^unexplored western part of the range.

The Nutzotin Mountains merge to the northwest into the Alaska Range, but 

the Mesozoic beds seem to end near Mentasta Pass, beyond which, at the head of 

the Chistochina and along the valley of the Delta River, metamorphic schists (Paleozoic?) appear to be the component strata of the range. The supposed syncline of
U. 8. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 45 PL. XXVHI

A. SUMMITS OF COAST RANGE FROM POINT NEAR JUNEAU. 

Showing dissected plateau feature.

SUMMITS OF CHUGACH MOUNTAINS. 

Showing dissected plateau feature.
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 45 PL. XXIX

A- SUMMITS OF ENDICOTT MOUNTAINS (ROCKY MOUNTAIN SYSTEM). 

Showing dissected plateau featuie. *

B. NORTH FRONT OF ENDICOTT MOUNTAINS. 

Showing relations to Anaktuvuk Plateau and planated surface of plateau.
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 4& PL. XXX

A. WAVE-CUT ROCK BENCH, NORTH SIDE OF PORT CLARENCE, SEWARD PENINSULA.

V, YUKON PLATEAU, 

From altitude of about 5,000 feet at north base of Nutzotin Mountains,
STRUCTURE OF PACIFIC MOUNTAIN SYSTEM. 257

Mesozoic rocks has therefore been indicated as ending near Mentasta Pass. (Map, 

PL XXI.)

Mendenhall has mapped a great fault" near the head of the Chistochina, which 

brings up the Permian rocks on the south against the metamorphic schist (Silurian?) 

on the north, with a throw estimated at between 8,000 and 10,000 feet. The eastward extension of this fault lies in the Nutzotin Mountains, where no detailed 

surveys have been made, while its projection to the west lies in an almost unexplored 

district.

The Nutzotin Mountain syncline probably continues into the eastern end of the 

Alaska Range, beyond which the structure is in doubt, but, following the same 

mountain mass westward for about 200 miles, evidence of synclinal structure is again 

found along the upper part of the Cantwell River Valley. (See section DD, PI. 

XXVII). This suggests that the general structure may be synclinal throughout 

this belt.

The section DD, transverse to the Alaska Range, extends from the Sushitna 

River on the south to the Tanana Valley on the north. The presence of a broad 

synclinorium is inferred from the fact that metamorphic sediments, probably chiefly 

Paleozoic, dip toward the axis of the range from both its margins, but between are 

probably many subordinate folds. Near the center of the mass is a syncline of 

sandstones and conglomerates, probably of Tertiary age, which is faulted on the 

north arm. In this section* again there is at least a suggestion of the same synclinorium structure of the Nutzotin Mountains.

The section includes a part of the Tanana Valley, near which it intersects an 

area of gneisses (Art-bean '.) overlain on the north by Pleistocene and on the south 

by metamorphic sediments (Paleozoic ?). For about 10 miles to the south the 

Paleozoic are covered by nearly horizontal Tertiary sandstone, and these are in 

part buried in Pleistocene gravels.

From the Cantwell Valley the Alaska Range and the bed-rock structures swing 

gradually to the south. For nearl}' 200 miles the structure has been inferred only 

from what is known of the geology of the mountains along the northwestern front, 

where a highly deformed series of Paleozoic sediments have been found with some 

infolded Eocene beds. The higher peaks, such as Mount McKinley, are probably 

stocks of granodiorite. The remarkably straight front of the range for 200 miles 

suggests sharp flexures or faulting.

The fact that the cross section of the Alaska Range (EE, PI. XXVII) at the 

Skwentna River, 200 miles southwest of the Cantwell, also shows a synclinorium 

suggests that this structure may be persistent throughout this belt. Here the 

closely folded Paleozoics, including Ordovician and Devonian strata on the west, 

are unconformably overlain by the sandstones, graywackes, slates, and limestones 

of the Tordrillo series (middle Jurassic), which are closely folded and faulted, 

and often cut by granodioritic igneous rocks similar to those of the higher peaks 

of the range. On the east the Jurassic beds rest unconformably on an intricate 

succession of igneous intrusives and lavas, with some sediments called the

a This fault has not been indicated on the accompanying map.

t part of the section south of the Cantwell River is generalized from very incomplete data.
258 GEOGRAPHY AND GEOLOGY OF ALASKA.

"Skwentna complex" and provisionally assigned to the Triassic. It will be noted 

that the Paleozoic beds which should underlie the Skwentna are not shown in 

this section on the east side of the range, but are probably present about 50 

miles to the northeast. On the west side the absence of the Skwentna rocks is 

explained by the period of erosion which preceded the deposition of the Jurassic. 

The central syncline of Jurassic rocks is supposed to narrow down to the north 

and to end near Mount McKinley. To the southwest the extension of this structure lies in the unexplored region west of Cook Inlet.

If the evidence of these three widely separated sections is to be correlated it 

would suggest a synclinorium structure for the entire Alaska Range. At its 

southern end broad belts of Mesozoic strata are included in the synclinorium, which 

seems to die out to the north only to appear again in Nutzotin Mountains. The 

presence of infolded Eocene sediments indicates that the last extensive deformation 

dates from Tertiary times.

Intrusions of granodiorite occur in large stocks along the axis of the range, 

and these are identical in composition arid probably in age with the batholiths of 

the Coast Range. As indicated on the geologic map (PI. XXI), these intrusions lie 

along the same general axis, while there appears to be a second zone of intrusions 

to the east along the Sushitna Valley.

A broad anticline appears to be the dominant structure of the Alaska Peninsula 

broken by extensive faults on the eastern area. This arch occurs in Mesozoic beds, 

chiefly Jurassic, which on the west overlie a complex of granitic igneous rocks of 

undetermined age. Along the crest of the arch a series of volcanic vents forms the 

higher peaks of the Aleutian Range. Like the Wrangell Mountains, the Aleutian 

Range owes its relief to the constructive action of Tertiary and Recent volcanoes 

which lie along an axis of crustal deformation. This axis is probably in part 

determined by movements in the earth's crust as early as the middle Mesozoic, 

but there is reason to believe that the folding has continued up to very recent time. 

The western extension of this anticlinal fold probably forms the submarine ridge 

along which the Aleutian Islands are strung.

STRUCTURE OF CENTRAL PLATEAU REGION.

No detailed structural features have been worked out in the great intermontane 

region where the bed-rock succession includes Archean gneisses, probably terranes 

of every division of the Paleozoic, Lower and Upper Cretaceous, Eocene beds, and 

probably some Pliocene. Several unconformities have been noted in this succession, 

and the pre-Upper Cretaceous rocks are closely folded and faulted while the Eocene, 

beds are locally often considerably deformed.

The zone of Archean gneisses which crosses the one hundred and forty-first 

meridian is flanked on either side by metamorphic sediment, indicating a broad 

anticline, and the same axis may find an extension along the gneissic area of the 

Cantwell Valley. To the north the metamorphic sediments are probably duplicated 

by an infinite number of closed folds overturned to the south. The structures of 

most of the younger beds along the upper Yukon remain to be determined, but the 

Eocene beds probably lie in synclinal basins.
STRUCTURE OF ROCKY MOUNTAIN SYSTEM. '259

The Cretaceous beds of the lower Yukon basin probably rest on Paleozoic 

terranes somewhere east of the Kuskokwim, and thence stretch to the northwest, to 

where they overlap on the Paleozoic or older sediments at the southern flank of the 

Rocky Mountains. It has been indicated that the central part of this area along the 

lower Yukon is occupied by Upper Cretaceous and Tertiary rocks. If such are the 

facts the Cretaceous beds occupy a broad syncline between two areas of older rocks.

The succession in the Seward Peninsula includes Silurian as well as older and 

younger metamorphosed Paleozoic sediments with some small basins of Tertiary or 

Mesozoic rocks, together with more extensive areas of recent lavas. The dominant 

structural feature of the central part of the peninsula is shown in the section FF 

(PI. XXVII), which shows that the oldest terranes occur in the Kigluaik Mountains. 

The axis of this range, which makes a horseshoe bend from the northeast to the east, 

and finally almost due south, appears to be a line of anticlinal uplift. The Kigluaik 

series is the oldest, and is made up of a basal member consisting of heavy crj-stalline 

limestones, with mica-schists, succeeded by a great thickness of mica-schists and 

gneiss, and the entire succession is cut by large granite dikes. These rocks are 

overlain by the Kuzitrin formation, mostly graphitic slate and quartzite, with a 

thickness of probably 1,000 feet. The next horizon is the Nome series, whose basal 

member includes micaceous and calcareous schists, with some limestone, succeeded 

by several thousand feet of massive limestone called the Port Clarence limestone, 

containing Upper Silurian fossils. In a larger way the Nome series shows rather 

broad, open folding, but where opportunities are given for detailed studies there are 

known to be many minor plications and often extensive faulting. In the northern 

part of the peninsula there are some indications of east-west structural lines, but 

these have not yet been followed up. Extensive intrusives of granite have taken 

place since the last extensive deformation.

STRUCTURE OF ROCKY MOUNTAIN SYSTEM.

The one cross section made by Schrader along the one hundred and fifty-first 

meridian atfords the only clew to the structure of the Rocky Mountain system. 

It appears that in its broader features the system can be regarded as anticlinal, 

for it is flanked on both the north and the south by Cretaceous beds (map, PI. 

XXI), but the details are complex. The generalized section (GG, PI. XXVII), 

after Schrader, shows two anticlinal axes, with sharp flexures and faulting, separated by a broad syncline. The southern anticline exposes the mica-schists of 

the Totsen series, succeeded by the Skagit formation, a heavy crystalline limestone. These rocks probably lie in the protaxis of the range. In the northern 

anticline, which is not nearly as well denned, only Devonian rocks are exposed, 

and Schrader's studies indicate a zone of block faulting rather than anticlinal 

structure. This faulting increases in complexity toward the northern escarpment, 

where it culminates in so intricate a S3^stem that Schrader's rapid journey of 

exploration can not be expected to yield final results regarding the structure. 

Between these two zones of maximum uplift a broad belt of rocks of diverse 

lithologic composition, called by Schrader the Fickett series, and provisionally 

assigned to the Carboniferous, appear to lie in a broad synclinorium.
260 GEOGRAPHY AXD GEOLOGY OF ALASKA.

The range, then, is bounded by Mesozoic beds on both sides, which on the 

south are sharply flexed, but on the north seem to be less plicated. The three 

axes recognized within the range strike east and west, and along the two outer 

there has been anticlinal folding, separated by a broad syncline. Schrader characterizes the general structure as consisting of broad folds, with faulting. The 

folds are sometimes accompanied by overthrusts.

There is some indication that the same anticlinal structure of the northern axis 

of the range extends westward to the Arctic coast to Cape Lisburne. No geologic 

work lias been done to the east of this section, except by S. J. Marsh, whose journey 

from Camden Bay to Chandlar River has already been referred to. Through the 

courtesy of Mr. Marsh, it is possible as this report goes to press to insert a part of 

his geologic and geographic notes relating- to northeastern Alaska. Though this 

material does not all properly belong to this part of the report, it seems worth while 

to publish all the notes on bed rock, both because they-include the only scientific 

observations made in this part of the territorj7 and because it gives opportunity to 

make record of a journey almost unique in the annals of Alaskan exploration. The 

notes have previously been published only in some of the Nome newspapers.

" The section of country of which this report treats lies between the meridians 

of 141° and 150° of west longitude and the parallel of 68° north latitude and the 

Arctic Ocean, and also includes the headwaters of the Chandlar River lying between 

146° and 148° west longitude south to its confluence with the west fork at about 

67C north latitude.

"The region actually explored lies between 144C 30' and 149° west longitude, 

and embraces a strip of country 114 miles in width and about 241 miles in length, 

stretching southward from the Arctic coast. This is the first exploration made of 

this district.

"The trip was under somewhat peculiar circumstances and, owing to a lack of 

proper means of transportation of supplies into the interior, I could make only 

cursory examinations.

"I arrived at Collinson Point, Camden Bay, September 21, 1901, in company 

with Mr. F. G. Carter, having taken passage on the schooner Helen from Port 

Clarence. Here we built winter quarters of driftwood and remained until the following April. During the winter all the dogs in the vicinity died of an epidemic of 

hydrophobia.

"The 7th of April, 1902, I left the coast alone, hauling 1,250 pounds by relays, 

and reached Cache Creek on June 1. at which time the snow disappeared. Mr. Carter 

also started a few days later, taking a similar route, intending' to make a short trip 

into the mountains and return to the coast in May, but I did not see him after leaving the coast.

"After building a cache of rock to protect my supplies 1 proceeded up the 

Kooguru [Canning] River and to the eastward along the northern slope of the main 

watershed, packing my supplies on my back. During the summer I sank many 

prospect holes and explored the mountain sides, studying the rocks as far as possible.

" The latter part of August I again descended the Kooguru to about 25 miles from 

its mouth, where I met Carter, Ned Carey, two Japanese, and a number of natives 

ascending the river with skin boats, the first human beings I had seen for a period
STRUCTURE OF KOOKY MOUNTAIN SYSTEM. 261

of one hundred and twenty-eight days. I accompanied them back to about 15 miles 

above Cache Creek, where we all built winter quarters, using willows, the only 

available timber.

"After hauling my supplies from the cache and making a short trip to the westward I settled down for a much-needed rest, spending some of the milder weather in 

surveying for map data and spare time in teaching two native children.

"On February 21, 1903, Carter left me, intending to cross the mountains to the 

Koyukuk, taking with him a native and his wife.

"On the 8th of April 1 again started with about 375 pounds, went up Right Fork 

and crossed the main watershed by a very low pass, which I named for Carter, as I 

found he had taken the same route.

" On April 30 1 overtook Carter and his natives about 30 miles down a river which 

1 afterwards found to be the Chandlar. As the river was now beginning to break 

up, I laid over three weeks, helping Carter to build a cabin and doing some prospecting, and again started out, packing my supplies and tools, prospecting along the 

main range. By the 4th of Juhr my supplies were practically exhausted and the 

country I was in was devoid of game. I was therefore forced to turn toward civilization, and taking what appeared to be the easiest route to the southeast, I finally 

came to a large river. Here I built a raft, on which 1 floated but a short distance 

when I encountered some bad rapids and came near losing my life. I was finally 

forced to abandon the raft and again take to packing, but soon becoming exhausted 

because of having been on practically a flour diet for some time, I built another raft, 

on which I floated for three days, when I came to an Indian village and found I was 

on the Chandlar. Here I obtained some dried moose meat, and a short time after 

Jack Carr, mail carrier from the Koyukuk to Fort Yukon, came along with a canoe 

bound for the latter place, to which I accompanied him, arriving there July 28.

"The watershed which divides the Yukon and Arctic drainage systems is formed 

by a continuous range of mountains, extending from Cape Lisburne slightly north 

of east to Mackenzie River. A subrange (designated on the maps as the Franklin 

Mountains) stretches eastward from the one hundred and forty-sixth meridian nearly 

along the sixty-ninth parallel, which is part of the main system and includes a number of large valleys. The elevation of the mountain at Carter Pass is about 4,000 

feet, and of some of the higher peaks 5,000 to 8,000 feet above the sea.

"A slightly rolling plateau, rising from banks of 12 to 35 feet along the Arctic 

Ocean to an elevation of 250 to 490 feet at the base of the ranges, stretches from the 

coast line to the Franklin Mountains, a distance of 19 to 34 miles, and west of the 

Kooguru [Canning] to the main range 60 to 140 miles.

"Till is found along the bays of the coast line. The most prominent points con' 

sist of large bowlders, rough masses of rock, chiefly of' granites and diorites, and 

heavy sands, all foreign to the vicinity.

"At Sunset Pass, a low gap through the Franklin Mountains, leading from the 

head of Ooselik [Kuselik] Creek to the head of the Barter River, alternate bands or 

layers of sandstones, conglomerates, and limestones are exposed. The limestones 

contain some fossils, mostly crinoids, and are but little changed by metamorphic 

action.
262 GEOGRAPHY AND GEOLOGY OF ALASKA.

"South and southeast of Sunset Pass and between the Franklin Mountains and 

the main range is a large basin which appears to have been formerly occupied by a 

lake and is now drained by the Barter River, which traverses a subrange through a 

narrow valley.

"In this basin slates are exposed which are generally soft, colored dark brown 

to black, and lie in a series of folds with a general nearly east and west strike. In 

places they are siliceous, and in a few localities are tilled with a network of small 

veins of quartz, generally much stained with oxide of iron. Near the center there 

occur several large bands of quartzite, also considerably stained by the decomposition of iron-bearing minerals.

"A series of these basins appears to occupy a similar position in relation to the 

two ranges to the east, and these are drained by the Hoola-Hoola, Bathhouse, and 

Turner rivers, all of which cut through the subrange.

"The same slates seem to continue to the west, except that the higher mountains 

are made up of limestones arid soft slates, lying generally nearly horizontal. These 

latter are rich in fossils, those in the limestones being generally crinoids. while the 

slates contain numerous worm burrows and many species of shells, none of which 

were determined. The higher mountains in the whole region, as far as a line running easterly and westerly near latitude 68° 10', are generally covered by the abovedescribed fossiliferous'limestones and slates; therefore, only a description of the 

rocks cut by the streams will follow.

"On lower Cache Creek and the Kooguru [Canning], from Carey Creek to a 

point some 12 miles above winter quarters of 1902-3, the streams have not cut down 

through the above-described rocks. From above point to the junction of the east 

and south forks the Kooguru has incised alternate bands of slates, quartzites, sandstones, and conglomerates, in places slightly stained by the decomposition of ironbearing minerals.

''The south and east forks of the Kooguru [Canning] rise in small basins well 

up in the main range and which are partially filled with glaciers.

"From the mouth of Right Fork to Carter Pass the rocks are principally slates 

and .sandstones, their structure indicating an immense anticlinal. At a point about 

10 miles above Hyaks Creek and at what appears to be the axis of this anticlinal 

occurs a large band of siliceous slate, carrying seams of graphite and bunches of 

calc-spar much stained by oxide of iron. On the south side of this band there are 

chloritic slates. This band can be traced for a long distance. It is cut by the head of 

the Sawanukto and its principal branch, the Evasha. Westerly from the Kooguru 

[Canning] the rocks under the universal limestone capping are more sandstones and 

conglomerates. Near the mouth of the Evasha occurs a large cropping of lignite. 

Little work was done, however, in this direction, and limited time did not admit of 

much examination. Westward from the Chandlar, between the sixty-seventh and 

sixty-eighth parallels of latitude, the rocks are largely mica-schists, with some crystalline limestones." ,, i , It would appear from Mr. Marsh's notes that this section is very similar to the 

one described by Schrader along the Colville on the south a belt of metamorphic 

schists and limestones, succeeded to the north by less altered fossiliferous limestones 

and slates. Approaching the Arctic coast are found sandstones, slates, and con-
GEOLOGIC HISTORY. 263

glomerates, which would appear to be of Mesozoic age. The latter would seem to 

belong to the same general horizon as the Cretaceous beds described by McConnell 

along his portage route from the Mackenzie to the Porcupine.

The Rocky Mountains where crossed by McConnell," along the Rat River 

portage, also seem to have a general anticlinal structure with numerous faults. 

The rocks, as far as known, all belong to the Cretaceous, and trend northwest and 

southeast parallel to the axis of the range. The relief is not as great as to the 

west, and for that reason erosion probably has not cut deep enough to expose the 

underlying Paleozoics found by Sclirader.

GEOLOGIC HISTORY.

To complete thin account of the geology it will be necessary to pass in brief 

review the succession of events from the earliest times up to the present, and in 

so doing to muster, as far as possible, all the facts of the stratigraphy and structure 

in one systematic scheme. The matter is so fragmentary that it will be possible 

to touch only the main facts of the history in outline, and the conclusions must 

remain in large measure speculative. Errors can not be avoided, and many false 

deductions will doubtless be made, yet a systematic treatment of the geologic 

evolution may not be without value. The pre-Tertiary history will here be treated 

at greater length than that of later date, which will receive more detailed consideration under geomorphology.

The gneisses (Archean 1) of the Yukon-Tanana district probably contain the 

oldest geologic records of the province, but these are very obscure, for the original 

character of the complex has been entirely destroyed during the repeated dynamic 

revolutions to which it has been subjected, and its genesis must for the present 

remain in doubt. There are probably elastics, as well as intrusives, included in 

the gneissic complex, which is largely made up of the rocks of undetermined 

origin which are usually classed as metamorphic, but all must for the present be 

placed in one group, which can be conveniently called Archean, though it may 

eventually, in whole or in part, find a much higher place in the stratigraphic 

column.

Whatever the origin of the gneissic series, it is certain that its typical members 

are much more highly crystalline than those of the known sediments. This fact is 

usually interpreted as indicating extensive deformation and metamorphism before 

the later sediments were laid down. It is not to be overlooked, however, that 

original Hthologic character, localization of deformation, and the intrusion of large 

igneous bodies may also bring about differential metamorphism, and that the 

relative degree of crystallization between rock masses is in itself alone not a safe 

criterion for age determination.

That some of these so-called Archean rocks are older than the undoubted elastics 

is indicated by the presence at several localities of a basal conglomerate resting 

unconformably on the gneisses from which it has derived its detrital material. 

These occurrences go to show that the gneisses were metamorphosed and eroded 

before the conglomerate, probably the basal member of the stratigraphic column,

« McConnell, R. G., Report on an exploration of the Yukon and Mackenzie basins, Northwest Territory, Ann. Kept. 

Geol. Nat. Hist. Survey Canada, vol. 4,1888-89, p. 120D.
264 GEOGRAPHY AKD GEOLOGY OF ALASKA.

was laid down. It seems then fair to assume that at sometime in the early 

geologic history there was a crustal movement which brought gneissic rocks above 

sea level. What little is known of the distribution of the conglomerate which 

resulted from this erosion suggests that the land mass or land masses were insular 

rather than continental, but beyond this and its probable pre-Silurian age, nothing 

is known of its form or size, or at what period it was elevated above the sea. 

It may have been a northwestern extension of the insular group, supposed to 

have existed in western North America at the close of the Archean, or it may have 

emerged from the sea at a much later date. Since this earliest denudation the 

gneissic areas have been deeply buried in accumulated sediments, and have been 

revealed only as a result of crustal movements which again brought them above the 

sea where they were uncovered by erosion. These later movements seem to have 

taken place along the same protaxis, and the present outline of the gneissic rocks 

may in a measure correspond with that of the first land mass exposed.

The cj'cle of sedimentation inaugurated with the deposition of the conglomerate 

which rests on the gneisses seems to have continued without any considerable 

interruption by dynamic revolutions to about the end of Silurian time. The 

deposits of this period which were laid down upon the conglomerate throughout the 

Yukon basin seem to have been of an arenaceous and argillaceous character and 

accumulated to a thickness measured by thousands of feet. If the stratigraphic 

correlations made of the pre-Silurian sediments are correct, there was a decrease of 

clastic material toward the northwest, which would indicate that it had been derived 

from a land mass to the southeast. The age of these early sediments being 

unknown, there are little data for speculations in regard to this land mass. As 

sedimentation went on the proportion of clastic material gradually decreased, and 

the deposits became more calcareous, indicating a subsidence of the sea floor and an 

accompanying retrogression of the shore line. These conditions seem to have 

persisted until late Silurian times, when the sea probably covered the greater part 

of Alaska, and the deposition of thousands of feet of comparatively pure limestone 

took place.

In short, the earlier sedimentary record indicates the deposition of thousands 

of feet of argillaceous and arenaceous matter followed by the accumulation of 

calcareous material also to a thickness of thousands of feet. Though the earlier 

sediments have yielded no organic forms, the latter on fossil evidence are assigned 

to the upper Silurian, and the entire conformable succession has been assigned to 

the Paleozoic. It is quite probable that volcanism was at times active during this 

long period of sedimentation, but of this there is no definite proof. It seems more 

certain that while the later sedimentary rocks of this epoch were being deposited, 

the earlier were so deeply buried as to have become indurated and were intruded by 

eruptive rocks.

Throughout the province, except possibly in the panhandle, an extensive 

dynamic revolution seems to have put an end to deposition in late Silurian or early 

Devonian time and brought about deformation and metamorphism to such an extent 

as to render the thin-bedded sediments as well as some of the eruptive rocks 

schistose, and to cause a recrystallization of calcareous and other material. This 

disturbance was accompanied by the injection of a large amount of igneous rock 

which also played a part in the metamorphism.
GEOLOGIC HISTORY. 265

As a result of these movements, a land area emerged from the sea, of whose 

extent little is known. Jn the middle Yukon basin an erosional interval gives a 

sharp line of demarcation between this and later crustal movements, and the same is 

probably true in northern Alaska, but in the panhandle no physical break has yet 

been found between the Silurian and Devonian, though the relative degree of metamorphism suggests that such a one did exist. As a matter of fact, however, this 

post-Silurian dynamic revolution, though regional in its effect, locally differed very 

much in intensity, a fact strikingly illustrated in the Seward Peninsula, where in 

some places the Silurian rocks are semicry stall ine, while in other near-by localities 

they are almost entirely unaltered.

The length of the period of denudation is entirely unknown, but in the Yukon 

basin it was of sufficient extent to bevel the upturned edges of the older terranes.

Sometime before the middle of the Devonian a gradual subsidence took place, 

which continued until the sea covered the entire province. In the Yukon-Tanana 

district, and possibly in the Copper River region, at about the time of this invasion, 

volcanic vents opened and poured out great masses of lava, together with extensive 

beds of tufa. This lava was deposited in part on land and in part in the sea. In 

the near-by waters extensive coral reefs furnished the calcareous matter for limestone deposits. In other parts of the province the aggregations of this period were 

entirely of a calcareous nature, and there was a marked absence of all eruptive 

material. The limestones thus deposited are of the most widely distributed Alaskau 

formations, having been identified nearly throughout the province by their corals of 

middle Devonian age.

The records of the succeeding epoch are obscure, but indicate that limestone 

deposition continued in some places during early Carboniferous times, while in 

others a considerable land area was exposed to erosion. Deposition was probably 

almost entirely checked by a crustal movement which took place about the beginning of the Permian and this was followed by subsidence. On the Yukon there 

is evidence of an extensive period of erosion which immediately antedated the deposition of the Permian sediments, but this has not been recognized elsewhere.

The Permian sea seems to have covered much the larger part of the province, 

for its sediments have been found along the Yukon, in the panhandle, and in the 

Copper basin, where they aggregate 7,000 to 8,000 feet, in the two latter districts 

the deposition was accompanied by the extrusion of volcanic rocks. In part of the 

province deposition apparently continued unbroken into the Triassic and was characterized by a gradual change from limestones to shales. It was ended by a crustal 

movement which deformed the beds, exposed a considerable land mass, and thus 

began another period of erosion. This uplift seems to have begun in Permian times 

in northern Alaska and progressed gradually southward during Triassic times, for 

the latter period does not seem to have left any sedimentary record north of the 

Pacific Mountains. In southeastern Alaska the indications are that the PermianTriassic cycle of deposition was closed by an extensive dynamic revolution which 

metamorphosed and deformed the Paleozoic sediments and probably left them very 

much as they are now.

Volcanism seems to have been active in the southern part of the Alaska Range 

and in the peninsula to the southwest during the Triassic, for this epoch is repre-
266 GEOGRAPHY AND GEOLOGY OF ALASKA.

sented in those regions by an igneous complex, in part made up of volcanic rocks 

which were deformed and eroded before the deposition of the Jurassic beds.

During Jurassic times deposition continued in the region of the Alaska Range 

and Alaska Peninsula and in northern Alaska until many thousand feet of sandstones, slates, and some limestone were laid down. As these are the only Jurassic 

sediments of Alaska, except the Jura-Cretaceous and possiblj' a narrow belt of elastics, which fringe the St. Elias Range on the south, it is probable that much the 

larger part of the province was dry land during this epoch.

A crustal movement in late Jurassic times interrupted ail sedimentation and was 

followed by large injections of igneous rocks. These intrusions, which embrace the 

great batholiths of the Coast Range, are the most extensive of any in Alaskan 

history.

At the close of this dynamic revolution a considerable area was above water and 

there began what was probably a short cycle of erosion followed by a far-reaching 

depression in Jura-Cretaceous times, when the entire land mass seems to have been 

submerged. The sediments which followed were coarsest in the panhandle and 

Copper River region, where they included considerable conglomerate, but to the west 

and northwest were largely impure limestones. This may indicate the existence of 

a land mass in northern British Columbia during this epoch.

The close of the Jura-Cretaceous deposition may be conveniently regarded as 

the end of the older geologic history of the province, for the later epoch had for the 

most part a more or less direct influence on the development of the present topography, and, as this subject will be treated in some detail below, only its salient features 

will here be recounted.

The various crustal movements of the late Paleozoic and Mesozoic were mostly 

of far-reaching character, but appear to have been intensified along the zones now 

marked by the mountain ranges, and the post-Jura-Cretaceous later deformations, 

though they have affected all parts of the province, seem also to have been most 

intense along the same zones where previous folding had taken place.

The Jura-Cretaceous deformation again revealed a considerable land mass and 

active degradation began. Much of Alaska has probably not been below sea level 

since the close of this epoch. A transgression of the sea, however, took place 

along the present Yukon Valley during Upper Cretaceous times, and this may have 

extended up to the Porcupine and northward to the present base of the Rockies. 

A part of the Arctic Slope region and possibly some of the Pacific littoral were 

submerged during this period. Deposition continued in the lower Yukon basin up 

into the Eocene, but in the upper Yukon basin the Eocene is represented only by 

fresh-water beds which seem to have been laid down in isolated basins.

In late Eocene or early Miocene times folding took place, which to some degree 

affected the entire province and is the last which has caused any considerable 

deformation, for all the subsequent movements were of an orographic character 

and had little or no local effect on the rock strata. This was accompanied by 

intrusions of igneous rocks. Uplift followed and during a long period of stability 

extensive erosion took place, during which the exposed land surface nearly throughout the province was reduced to a peneplain which was subsequently uplifted and 

dissected.
GEOLOGY. 267

G^IOMORPilOLOGY. « 

INTRODUCTION.

As the consideration of the origin of physiographic features demands a comprehensive knowledge of the lithology, structure, and distribution of the rock 

masses, as well as of the successions of recent earth movements, it is evident that 

the groundwork is yet very incomplete. There are almost endless varieties of land 

forms in the province, every part of which offers a host of physiographic problems, 

but only a few of them have been investigated. This writing must, perforce, be 

limited to the general features of geomorphology, and these will be treated only in 

brief outline. It is hoped that the tentative conclusions which will be advanced may 

at least serve as working hypotheses until the surveys now in progress may yield 

more definite results.

Though a full account of physiographic features has been given under the 

heading "Descriptive geography," it will be well to review this matter briefly 

before taking up the consideration of the origin of the topography. This will 

be followed by a genetic classification of the more important topographic types, 

while the last subdivision of this section will be devoted to a systematic discussion of the geomorphology.

TOPOGRAPHY

The broad cordillera which stretches northwestward through the western 

United States traverses western Canada, and extends into Alaska, where it swings 

west and southwest parallel to the great bend in the, shore line of the northern 

Pacific (see Pis. 1 and VII). This crescentic sweep has a wide import, for in Alaska 

the tread of the cordillera maintained from Mexico for 3,000 miles to the northwest changes its direction and turns to meet the northeastern extension of the 

Asiatic continent, and, as this feature is repeated in the bed-rock terranes, it can 

be said to mark the change from American to Asiatic structure. The extension 

of the structural and physiographic provinces of Alaska are to be sought in 

Siberia to the west of Bering Sea and Strait.

This cordillera is outlined by two mountainous zones separated by a broad 

upland of relatively low relief, called the Central Plateau region. The southern 

highland belt the Pacific Mountain system is a rugged mass 100 to 200 miles 

wide, which in many places rises almost sheer from the waters of the Pacific, 

while inland it often descends with almost equal abruptness to the upland region. 

The northern highlands, a northwestern extension of the Rocky Mountain system, 

are of lesser relief, though they also form a rugged mass 100 to 200 miles in 

width. Their inland slopes appear to merge with the highlands of the central 

upland region, but on the north they fall off abruptly to the fourth province 

the Arctic Slope region.

The coasts of northern and southern Alaska are in striking contrast. 

Innumerable waterways and islands break the shores of the Pacific, and the land

a An abstract of a part of this section has been published by the writer in a paper entitled " The (Geography of Alaska 

with aa Outline of the Geomorphology." Eighth International Geographic Congress. Washington, 1905. pp. 204-230.

17211 No. 45 06 18
268 GEOGRAPHY AND GEOLOGY OF ALASKA.

ascent is usually steep from tide water, while seaward the descent to deep water is 

equally abrupt. On the other hand, the shores of Bering Sea and the Arctic Ocean 

are even, the land slopes up gently inland, and the sea is shoal for a long distance 

from the coast.

The Pacific Mountain system of Alaska trends northwesterly to about the one 

hundred and forty-ninth meridian, where it makes an almost right-angled bend, continues southwest, but with decreased relief, to Bering Sea. The system comprises 

four dominant ranges the Coast, St. Elias, Alaska, and Aleutian together with 

some lesser highland masses and two areas of low relief, the Copper River Plateau 

and the Sushitna Valley.

The Central Plateau region is very different from the bordering mountains, 

for here bold ranges and sharp peaks give way to a much dissected rolling upland 

with flat-topped, interstream areas having a general accord of summit level. These 

mark the surface of a dissected plateau, which has given to this province its 

name (PI. VII).

In its narrowest part, near the one hundred and fifty-second meridian, the plateau province has a width of but 200 miles, but broadens out both to the southwest, 

where it presents a frontage to Bering Sea of nearly 500 miles, and to the southeast 

in Canada, where it widens to 300 or 400 miles. The altitude of the plateau remnants, 

varying from 1,500 to 6,000 feet, is greatest along the margin, and its surface also 

shows a general incline to the north and west. Several broad lowlands lie within 

the plateau region, and near Bering Sea it gives way to a wide coastal plain.

The Rocky Mountain system of Alaska, called the Endicott Mountains by 

Schrader, is formed of several high ranges which stretch from the international 

boundary westward to the Arctic Ocean, and constitute the divide between the polar 

and Bering Sea waters. These ranges are little explored, but near the boundary 

probably reach altitudes of 5,000 to 8,000 feet, while to the west they decrease 

in height and near the Arctic appear to be separated into a number of minor ranges 

by broad valleys.

On the north the Rocky Mountains fall off abruptly to the Arctic Slope region, 

which is of relatively low relief and divisible into two subprovinces, the Anaktimik 

Plateau and the Coastal Plain. The Anaktuvuk Plateau has an altitude of 2,500 

feet at the base of the mountains and slopes gently for 60 miles to the north to a 

scarp which marks the beginning of the Coastal Plain.

The drainage of Alaska flows southerly to the Pacific Ocean, westerly to Bering 

Sea, and northerly and westerly into the Arctic Ocean. Several trunk streams, such 

as the Stikine, Taku, Chilkat, and Alsek rivers, which rise in broad, open valleys 

within the Central Plateau region and then traverse the coastal ranges by steepwalled canyons, drain the southern part of the Pacific Mountain system. A broad 

depression lying within the Pacific Mountains is drained by another group of rivers, 

including the Copper, Matanuska, and Sushitna.

The Central Plateau region sends nearly all its waters to Bering Sea through the 

Yukon, the master stream, but the Kuskokwim also drains a part of this province. 

These and their many large tributaries usually occupy broad valleys, with gently 

sloping walls, sometimes opening out into large lowland basins.
CLASSIFICATION OF TOPOGBAPHIC TYPES. 269

The waters of the southern slope of the Rocky Mountain system go to tributaries of the Yukon, while those of the northern slope flow into the Arctic Ocean 

through north-south valleys which traverse the Arctic Slope region. The western 

drainage of these mountains goes to the Arctic through the Noatak and Kobuk 

valleys.

GENETIC CLASSIFICATION OF TOPOGRAPHIC TYPES. 

(GENERAL STATEMENT.

The descriptive geography took account only of form and grouping of the 

topographic features, entirely disregarding their genesis and evolution. Such a 

classification is essential for the purposes of geographic description, for it-emphasizes 

the orographic continuity of some of the forms and shows the interrelations of 

others, but a discussion of their origin calls for a genetic grouping, and this will 

here be attempted.

Some of the land forms, such as the volcanic mountains, are of comparatively 

simple origin, and lend themselves well to such a genetic classification, while the 

evolution of others, such as the Yukon Valley, is so complex that it can only in part 

be determined from the facts in hand. The size of the province and the variety of 

its land forms will make it impossible to here describe all of the topographic types, 

and therefore only those will be considered which seem to have a close connection 

with the general geomorphologic problems.

MOUNTAINS.

GENERAL TYPES.

Mountains and ranges, or areas of greatest relief, are the most striking of the 

topographic forms and often among the most complex. In general terms they are 

areas in which erosion has not kept pace with elevation, and usually mark zones of 

rapid recent uplift. Of equal or greater height, though in this province of far less 

extent, are the mountains which owe their relief to the accumulation of volcanic 

material faster than it is removed by erosion. Some of these volcanic ranges lie in 

zones of recent crustal movement, and their altitudes may in part be due to uplift. 

A third type of mountains of subordinate importance, though it probably includes 

the highest individual peaks of the province, are the residuary masses left by differential erosion, whose preservation is determined either by the Hthologic composition 

of component rocks, or by accidents of erosion and remoteness from the main 

drainage channels.

MOUNTAINS OF RECENT UPLIFT.

To this class belong most of the highland areas, the greater part of which lie in 

zones of recent crustal movement and are the resultants of the interaction of uplift 

and erosion. As these mountains are carved by erosion from an uplifted area, their 

contour is determined in a measure by the older topography, but to a still greater 

degree by the character and structure of the exposed bed rock. Unfortunately, 

often all vestiges of the older topography have been removed, and in many cases the
270 GEOGRAPHY AND GEOLOGY OF ALASKA.

bed-rock geology of the highland areas is almost unknown. Glaciation, too, has 

played an important part in the sculpturing of the high ranges, for the\* are, or have 

been within recent times, the loci of the accumulation of glacial ice.

The character of the uplift, whether rapid or slow, uniform or differentiated, 

will determine the topography. To properly trace the evolution of the mountains, 

all of these factors should receive consideration, though here but a few are imperfectly understood, while many are entirely unknown.

The Coast Range is an irregular aggregate of peaks and crest lines with 

little symmetry of arrangement, except a rough alignment along a northwestsoutheast axis. The whole aspect of this range is precipitous and rugged, with 

needle peaks, knife-edged crests, and sharply incised drainage channels, but this 

young topography was carved out of older highlands whose surface was base-leveled 

(PI. XXVIII, A).

Evidence of this old base-level is preserved in the summits of the present 

mountains, which rise to a strikingly uniform altitude ranging from about 7,500 

feet in British Columbia to about 5,000 feet in Alaska. Viewed from a point at 

least as high as the general level, the summits fall into the same plane with an 

even sky line, broken here and there by pyramidal peaks rising above the general 

crest line, the fast disappearing remnants of unreduced areas.

On the inland side at its northern end the Coast Range merges with the 

Yukon Plateau, while seaward it is not sharply differentiated from the highlands 

of the Alexander Archipelago. The uplift was greatest in the southern part of 

the range, where the summits are 8,000 to 9,000 feet above the sea, and several 

thousand feet higher than the surface of the interior plateau. It decreased to 

the north, for at Lynn Canal the summit level is only about 5,000 feet, while 

at Cape Spencer 50 miles to the northwest, Gilbert" recognized the same degradational surface in an upland only 2,500 to 3,000 feet high, which here abuts 

abruptly against the southern slope of the Fairweather Mountains. Passing 

inland of the St. Elias Mountains to the north, the Coast Range decreases in 

altitude, and its upland surface seems to merge with that of the interior plateau 

near the northern boundary of British Columbia. The relations of the Coast Range 

to the interior plateau will be considered in a later paragraph.

The irregularity of the Coast Range topography is what might be expected 

in a dissected plateau, but the lack of symmetrical arrangement of crest lines is 

also largely due to the character of the bed rock. Here there are no hard and 

soft layers to be emphasized by degradation, nor are there any dominant 

structural lines to determine lines of erosion, for nearly the whole mountain 

mass is made up of massive granodiorite of considerable lithologic uniformity. 

As all parts of this highland mass offer about the same resistance to erosion, no 

dominant crest lines were established and the drainage channels must have been 

determined by antecedent conditions. Though this holds true of the larger features 

of the land sculpturing the detailed dissection has been in a measure influenced 

by lines of weakness caused by fracturing of the homogeneous rocks. Glacial 

erosion, too, has played an important part, for all of the larger drainage

a Harriman Alaska Expedition, vol. 3, p. 125,
TOPOGRAPHIC TYPES MOUNTAINS. 271

channels have been ice scoured, while the many cirques are characteristic features 

of the topography.

The Stikine and Taku rivers traverse tho range in steep-walled valleys, which 

are in strong contrast to their open headwater basins. They have the characteristics of antecedent water courses, and as such bear evidence of the slowness of 

the uplift of the land mass from which the Coast Range was carved.

The elevation was markedly differential, for in British Columbia the altitude 

of the old dogradational surface is 8,000 or 9,000 feet, while at Lynn Canal it is 

5,000 feet, and at Cape Spencer, near at hand, it is less than 3,000 feet above 

the sea. The elevated plateau from which the present Coast Range was carved 

had then a warped surface with a general northerly tilt. There is reason to 

believe that a profile transverse to the present mountains would everywhere show 

a slope of the old peneplain to the east and west from what is now about the 

axis of the highland mass.

The Pacific coastal zone has been the scene of many recurrent dynamic 

revolutions from early Paleozoic to Mesozoic times, but though these arc recorded 

in the bed-rock structure, whatever expression they found in the topography has 

been nullified by subsequent degradation, for the present relief is due entirely 

to comparatively recent uplift. The granodiorite batholith was intruded in 

Jurassic times underneath a heavy blanket of strata, which were displaced and 

possibly in part absorbed/' and the resulting relief on the earth's surface was 

removed by erosion, tho igneous core exposed, and finally during a long period 

of stability the present mountain belt, together with the adjacent regions, was 

reduced to a peneplain, across which the rivers flowed to the Pacific. Differential 

uplift raised this lowland area, and it became an undulating plateau from which 

the rejuvenated drainage system carved out the present Coast Range. So slow 

was the uplift that the larger water courses maintained their valleys across it.

The axis of the Coast Range, which had been a locus of previous disturbances, 

was uplifted higher than the interior region, so that while the latter preserved to a 

large extent its plateau character, the Coast Range, by reason of the greater 

relief, was extensively dissected and thus became the present rugged, irregular 

mountain mass, which has preserved its plateau features only in the even crest lines.

The rugged highlands, 80 to 100 miles in width, stretching from Cross Sound 

to the Copper River, and forming the main mass of the St. Elias Range, are almost 

unsurveyed and geologically unexplored. With a mean altitude of probably over 

10,000 feet, embracing many peaks over 12,000 feet, and culminating in Mount St. 

Elias (18,100) and Mount Logan (19,500), it is the greatest neve field of the North 

American continent. On the south it descends through a series of foothills to a 

steep-shelving coastal plain, often buried in huge piedmont glaciers, while inland it 

ends in a great scarp at the margin of the Yukon Plateau (PI. X, B).

It has been shown that on the southeast, at Cape Spencer, the summit level of 

the Coast Range abuts abruptly against the flank of the Fairweather Mountains 

(a part of the St. Elias Range), and, as Gilbert has indicated, the two provinces are 

sharply differentiated.

" Lawson, A. C., The Oordillerau Mewozoit' revolution: Jour. Geol., vol. 1, 1,S93, pp. 579-586.
272 GEOGRAPHY AND GEOLOGY OP ALASKA.

To the west of Mount St. Elias the range splits, and the Skolai and Nutzotin on 

the north and the Chugach Mountains on the south diverge to inclose the Mount 

Wrangell volcanoes and the Copper River basin. The Chugach Mountains are a 

broad, rugged, highland belt, whose summits reach a uniform altitude of about 

6,000 feet, with occasional peaks of 7,000 and 8,000 feet (PL XXVIII, £). This 

upland surface, like that of the Coast Range, is interpreted as evidence of a former 

surface of degradation. The topography of the northern wing of the St. Elias 

Range also bears evidence of base-leveling at about the same altitude.

Tracing the southern coastal mountains westward and around the bend into the 

Kenai Peninsula there is here also an upland surface, which, according to Gilbert," 

is probablv the remnant of an ancient peneplain. He recognized a similar feature 

in the upland of Kodiak Island, 100 miles to the south. The altitudes of the 

planated surfaces at the two latter localities have not been determined, but are 

probably only a few thousand feet.

The St. Elias Range is broken by one broad water gap through which the Alsek 

River finds its way to the sea. The walls of this valley, which is unsurveyed, are 

reported to be interrupted by a broad bench above which the slopes rise gradually 

and below which the river has incised a narrow channel. Similarly, the Chugach 

Mountains are bisected by the Copper River which traverses them in a narrow 

valley.

The St. Elias Range can then be defined as a block of rugged topography, 

with a mean altitude of probably 8,000 to 10,000 feet, bounded on the south, 

north, and west by scarps which fall off to uplands of lower altitude, whose 

summits mark dissected plateaus. It is bifurcated by the Alsek Valle3', which 

will be shown to be probably in part of an antecedent character.

It seems certain that the axis of the range has been a zone of crustal 

movement since early Paleozoic times or older. Mount St. Elias itself appears 

to be a great intrusive stock of a dioritic* rock. Its great altitude is due 

probably in part to the greater resistance offered to erosion by this hard rock 

than by the adjacent schists, and in part to the fact that it and the adjacent 

high peaks appear to be in the locus of maximum uplift. Along the southern 

flank much folded and faulted beds have been found, which Russell c reports may 

be of early Tertiary age, but of more physiographic interest is the proof of 

very recent uplift which he found in the occurrence of Pleistocene or Recent 

marine organisms at an altitude of 5,000 feet.

These facts, together with the high relief and jagged character of the range, 

all point toward an extensive upward movement. The Pleistocene and Recent 

glaciation has been very active in the St. Elias Range, but the resulting 

topography is still in a large measure buried under the present glaciers and 

neve fields.

The Alaska Range, the third of this type, attains its maximum altitude in 

Mount McKinley (20,300) and Mount Foraker (17,000), which tower above the 

well-defined crest line of 8,000 to 10,000 feet (PI. VIII, £). These majestic

a Harnman Alaska expedition, vol. 3, p. 177.

i'Filippi de Pilippo, The ascent of Mount St. Elias, New York, 1900, pp. 234-236.

c Russell, I. C., Expedition to Mount St. Elias. Nat. Geog. Soc, Mag., vol. 3, 1891, pp. 170-175.
TOPOGRAPHIC TYPES MOUNTAINS. 273

peaks lie near the center of the axis of the range, near where it swings from 

northeast to east. From this central mass its mean altitude decreases in both 

directions along the axis. This rugged mass, which defines the northern boundary 

of the Pacific Mountain system, is extended to the east by the Nutzotin 

Mountains. The crest line lies close to the western margin, where the mountains 

fall off abruptly to a gravel-floored piedmont plateau, with the sharp line of 

demarcation which is such a striking topographic feature for upward of 200 miles 

along its northern front. (Pis. XI and XXXII.) The main mass of the range, 

which stretches for about 40 miles east of the crest line, has been but little explored, 

but probably includes many high transverse ridges separated by glacial-scoured 

valleys, some of which are still filled with ice.

In the geologic discussion it has been noted that the component strata of the 

Alaska Range date back at least to the Ordovician and include Jurassic, but the 

plication of these older horizons has had no direct effect on the present topography. Of more import is the presence of infolded Eocene beds in the heart of 

the mountains, indicating extensive dynamic revolution since early Tertiary times. 

It was probably after this Eocene deformation that an area was uplifted from 

which the present mountains were carved. Though this movement may have 

begun in Middle Tertiary times, the present altitude of the range must be due to 

more recent elevation, for the youthful character of the topography as well as its 

great relief indicate that erosion has not been active for a long period.

Mount McKinley and Mount Foraker both lie in the zone of maximum uplift, 

but, like Mount St. Elias, their extreme heights may be in part accounted for by the 

fact that they, too, are formed of stocks of granodiorite, which offer greater 

resistance to erosion than do the adjacent sediments.

The facts presented suggest that the mountains have been carved from an 

uplifted area whose culminating crest corresponded in a general way with the 

present crest line of the range, and that the maximum upward movement was 

near Mount McKinley. This highland mass sloped off gently to the east and 

south, but fell off abruptly to the west, like the present range, which would indicate a sharp flexure or fault along the western margin. What is known of the 

bed-rock geology bears out these suggestions, for the oldest strata along the axis 

of the range are found near Mount McKinley, and along the western front there 

is every evidence of intense deformation.

The rugged highland belt stretching across northern Alaska is an extension of 

the Canadian Rockies. Westward from the international boundary the axis of the 

ranges has a direction a little south of west, and the relief gradually decreases from 

7,000 to 8,000 feet on the east to 5,000 and 6,000 feet at the one hundred and fiftyfirst meridian, and to probably 1,000 or 2,000 feet in the highlands north of 

Kotzebue Sound. On the north the mountains probably fall off abruptly to the 

Anaktuvuk <l Plateau (PI. XXIX, jB) throughout their extent, but on the south the 

descent to the interior plateau seems more gradual.

This highland belt, which probably includes several distinct ranges, is but little 

explored. The western end of the system is known to be broken into distinct

aSchrader, F. C., A reconnaissance in northern Alaska: Prof. Paper r. 3. Geol. Survey No. 20,1904, pp. 39^15.
274 GEOGRAPHY AND GEOLOGY OF ALASKA.

ranges by the broad longitudinal valley's of the Kobuk and Noatak rivers, but except 

for these two rivers the drainage as far as known is carried north and south by 

large transverse streams, fed by smaller tributaries having- longitudinal courses. 

The watershed lies close to the northern front, and from this the main drainage 

channels flow almost due north or duo south. During recent times the higher parts 

of the range were the collecting ground of glaciers, which helped to scour out 

the valleys, and in some cases reached far out from the mountains into the adjacent 

lowlands.

In the central part of the range an even sky line and accordance of summit 

levels has been noted by Schrader and interpreted as indicating an uplifted and 

dissected base-level of erosion. (PL XXIX, A.) He first noted this feature in 

the Chandlar 0 and Koyukuk basins, at an altitude of 6,000 feet, and later was able to 

trace it northward along the John 6 River Valley and across the divide. The degradational surface seems to maintain a remarkable uniformity of altitude (6,000 feet) 

throughout the area in which it has been recognized. The base-leveling seems to 

have been very complete, for Schrader observed practically no unreduced areas 

standing above the peneplain.

As regards the structural geology, there is little to be said which would throw 

light on the genesis of the present topography. Of the two anticlinal axes c which 

have been described the southern is probably the older, and probabty dates from 

early Paleozoic times. The Carboniferous is the youngest horizon which has been 

found within the mountainous belt, but the evidence of the absence of Mesozoic is 

purely negative. Only Cretaceous beds have been found along the PorcupineMackenzie divide of the Rockies, and in Alaska the Cretaceous beds lying both north 

and south of the mountains are deformed, and seem to have been involved in the last 

important dynamic revolution.

These facts indicate that the component strata of the Rocky Mountains have 

passed through many recurrent epochs of deformation, the last of which was probably in late Mesozoic or early Tertiary time. These movements have in no direct 

way affected the topography of the only part of the range which is known, for the 

relief induced by this deformation was abraded to base:level, and a succeeding uplift 

gave a highland mass out of which the present topography has been carved. The 

uplifted Eocene strata on the north side of the range are gently folded and somewhat faulted, while the succeeding Pliocene are entirely undisturbed, indicating 

that the last crustal disturbance followed the deposition of these lower or middle 

Eocene and antedated the deposition of the Pliocene. The whole aspect of this 

highland suggests a maximum uplift along the present northern axis of the range, 

from which the main watercourses took consequent courses to the north and south.

In the preceding discussion, incomplete as it is, certain facts regarding the 

probable genesis of the highland masses have been developed. First, erosion has 

probably removed any areas of high relief which may have resulted from the many 

recurrent crustal disturbances which antedate late Mesozoic or early Tertiary times;

« Schrader, F. C., A reconnaissance in the Chandlar and Koyukuk basins: Twenty-first Ann. liept. U. S. Geol. Survey. 

pt. 2, 1900, p. 463.

6 Prof. Paper D. B. Geol. Survey No. 20, p. 42. 

c See Structure, p. 259.
TOPOGRAPHIC TYPES MOUNTAINS. 275

second, in early or Middle Tertiary time several of the areas now in high relief 

were reduced to a peneplain; third, this cycle of erosion was followed by differential 

uplift and from the highlands which resulted the present topography was carved.

VOLCANIC MOUNTAIN KANGES.

Of volcanic ranges largely of constructive origin there are only two in Alaska 

the Aleutian Range, which stretches through southwestern Alaska, and is continued 

in the highlands of the Aleutian Islands, and the Wrangell Mountains, which 

lie between the two forks of the St. Elias Range. Besides these there are some 

isolated volcanoes, such as Mount Edgecumbe, near Sitka. in southeastern Alaska.

The Aleutian Range is composed essentially of a series of typical volcanic cones 

distributed along a northeast-southwest anticlinal axis, which was a zone of deformation as early as the Triassic, and along which there may have been recent uplift. 

The extrusion of the volcanic material probably began in Tertiary time, and some 

of the volcanoes are still active. Many of these have the beautifully symmetrical 

forms typical of ash-built cones (PI. X, A).

The Wrangell a Mountains, an irregular group of volcanoes, form a rugged 

highland mass, having an area of about 100 by 50 miles and a mean altitude of 

probably over 10,000 feet, with some individual peaks rising to 15,000 feet. The 

mountains are built up of volcanic extravasations, which appear to rest on the 

surface of the same elevated plateau, which is defined by the summit level of 

the Chugach Mountains. Volcanism has been active probably since late Mesozoic 

times, but the present relief is largely due to outflows of lava since middle or late 

Tertiary times. The individual peaks are of the unsymmetrical type of lava cones 

(PI. IX), and are in contrast with the ash cones of the Aleutian Range (PI. X, A).

RESIDUAL MOUNTAINS.

The residual mountains form a third group, which, though subordinate from 

the standpoint of dimensions, is of physiographic import. These embrace a few 

small highlands and innumerable individual peaks, whose relief is due either to 

position relative to main drainage channels or because the resistance to abrasion 

of their component rocks has left them unreduced during the erosion of adjacent 

areas. Many of these mountains are true monadnocks, as their surrounding areas 

have been base-leveled, but the group as a whole will hardly fall within the definition of a monad nock, and hence they are here termed residual mountains. In not 

a few instances the relief of these residuary mountains is in part due to the fact 

that they lie in loci of maximum uplift. Highlands of this type are very common in 

the Central Plateau region, but attain no great altitude. The Glacier Mountains 

of the Fortymile region, which stand considerably above the general altitude of 

the Yukon Plateau, are examples, and there are many more. It is probable also 

that the Kigluaik Mountains, of the Seward Peninsula, have a similar origin. 

Many of the highest peaks of Alaska are of the residual type, though this relief 

is usually emphasized by differential uplift (PI. VIII, A and B).

aSchrader, F. C., and Spencer, A. C., The Geology and Mineral Resources of a Portion of the Copper Kivcr district: 

Special publication U. S. Geol. Survey, p. 67.
276 GEOGRAPHY AND GEOLOGY OF ALASKA.

PLATEAUS.

GENERAL TYPES.

The plateaus of Alaska, like the mountains, fall into two general types first, 

areas planated by erosion and subsequently elevated; and, second, constructional 

plateaus. Those of the first type do not differ genetically from the highland areas, 

whose summits mark degradational surfaces already grouped with the mountains. 

Though the distinction between these two land forms is to a certain extent 

arbitrary, it seems desirable to retain the name plateau only for such uplands 

as actually preserve something of the plateau features, besides the accordance of 

summit levels.

The plateaus of the degradational type are of far greater extent in Alaska 

than those of the constructional type. The first can be conveniently classed as 

"plateaus of the dissected peneplain type," and the second as "constructional 

plateaus."

PLATEAUS OF THE DISSECTED PENEPLAIN TYPE.

These can be further subdivided into those whose planated surface is due to 

subaerial erosion and those of marine abrasion. The first is well represented in 

the province, but of the second type there is only one example known and that is 

of small extent.

The Central Plateau region has been described as a great upland, diversified 

by numerous drainage channels, whose interstream areas mark the surface of a 

dissected plateau in Alaska called the "Yukon Plateau." It has a general slope 

to the northwest, and its surface is rolling and varies locally in altitude. The 

plateau is best seen from a summit which stands at about the level of its surface, 

where the observer will be impressed with the even sky line sweeping off to the 

horizon (PI. XXX, £), and broken only here and there by isolated residuary masses, 

which stand above the general level. So even and flat-topped are the interstream 

summits that the plateau closel}' resembles a constructional surface. The plain, 

however, bears no constant relation to rock structures, and erosion has beveled 

the upturned edges of hard as well as soft strata. In fact its surface is entirely 

discordant to the highly contorted metamorphic rocks which make up much of 

the plateau.

Some of the flat-topped summits which mark this plain include smooth and 

unbroken areas several square miles in extent, but as a whole the plateau surface 

is by no means a horizontal plain, but rather, as has been shown, a gently rolling 

upland.

The plateau is deeply dissected by its drainage system, which has carved out 

broad valleys several thousand feet below the summit level. In most instances the 

valley slopes rise gently to the plateau surface, and the exceptions can be explained 

by recent local elevations, which have caused an acceleration of stream cutting.

The surface of the plateau falls off gently to the north from about 6,000 feet 

in central British Columbia to 5,000 feet near the head of the Lewes River. Along 

the northern base of the Pacific Mountains it retains this altitude as far as the Tanana 

basin, whence it falls off northward to about 4,500 feet at the mouth of the White
TOPOGRAPHIC TYPES PLATEAUS. 277

River and to less than 4,000 feet in the Fortymile basin. Toward the west it 

continues to decrease in altitude, and the interstream areas which mark the plateau 

level have an altitude of about 3,500 feet in the Birch Creek region, and of probably 

less than 2,000 feet near the mouth of the Tanana.

The divide between the Yukon and the Koyukuk lies in an upland region whose 

summits have an altitude of between 2,500 and 3,500 feet. The summits are 

probably remnants of the plateau and indicate a general rise northwest of the 

Yukon.

Schrader" recognizes throe base-levels of erosion in northern Alaska. The 

highest is the summit level of the Endicott Mountains (6,000 feet) already described, 

which falls off on the south to an upland area which has an altitude of about 3,000 

feet and is correlated by him with the Yukon Plateau. The third is the so-called 

Koyukuk Plateau, which is traced in a general accordance of the summit levels 

(1,200 feet) of the lower hills and ridges of the Koyukuk Valley. There is here an 

excellent example of the difficulties of studying physiographic forms with the aid of 

the incomplete maps based on reconnaissance surveys. While Schrader's field 

observations lead him to note that the lower plateau is easily recognized, and the 

higher plateau is obscure, a diametrically opposite conclusion is obtained from a 

study of the contour maps. On these the flat-topped summits between 2,500 and 

3,500 feet show a general accordance in altitude rising gradually toward the base of 

the mountains, but the lower 1,200-foot level is recognizable only in some gentle 

valley slopes whose lower relief might be due to more rapid erosion, as they lie near 

the main drainage channels and appear to be cut on softer rocks.

As the Koyukuk Plateau has been traced over only a small area it can be 

disregarded in this general discussion. It is worthy of note, however, that there 

is some evidence of degradational surfaces of a later date than the Yukon Plateau 

in other parts of the plateau region, and more detailed work may yet lead to a 

recognition elsewhere of this later planation.

According to Schrader the Yukon Plateau has an elevation of 2,500 to 3,000 

feet in the upper Koyukuk and Chandlar basins, and a study of the map suggests 

that it may rise still higher as the mountains are approached. Its relation to the 

summit level of the Endicott Mountains will be a subject for further scrutiny, 

when facts will be presented which suggest the identity of the two peneplains.

There is little clew to physiographic features of the northeastern part of the 

Yukon, but the plateau probably rises toward the base of the Rocky Mountains. 

McConnell* has described a plateau of 5,000 feet altitude at the Porcupine-Mackenzie 

divide, which may represent the same level. There is also a hiatus in topographic 

mapping in the lower Yukon basin, but the ridges and hills are known to decrease 

as Bering Sea is approached, and it appears that the plateau level slopes gradually 

toward tide water, and possibly passes beneath the coastal plain.

In the Seward Peninsula several distinct base-levels of erosion are recorded 

in the topography. The most striking is found in the general accordance of summits (1,500 to 2,000 feet) (PL XI11) in the rolling upland region of the northern

(iSehrader, F.. C., A reconnaissance in northern Alaska: Prof. Paper U. S. Geol. Survey No. 20, pp. 44-45. 

bMcConnell, E. G., An exploration in the Yukon and Mackenzie basins: Ann. Kept. Geol. Nat. Hist. Survey Canada, 

new .Her., vol. 4, 1889.
278 GEOGRAPHY AND GEOLOGY OF ALASKA.

section of the peninsula, but there are at least one younger and probably one or 

more older planated surfaces. It will be shown elsewhere that in recent times 

the peninsula has been a locus of instability. Rock-cut terraces found up to an 

altitude of l,700 a feet are interpreted as evidence of recent elevation, while tidal 

estuaries afford equally strong evidence of recent depression. That these movements of the earth's crust have been differential is made evident by local warping/' 

which has had an important influence on the topographic development.

The surface of the Yukon Plateau, in a general way, has the form of a broad, 

shallow trough, pitching to the north, whose axis, coinciding with the valley of the 

Yukon, trends northwest to the Arctic Circle, and then bends to the southwest. In 

other words, the trough makes a nearly right-angled bend and pitches toward Bering 

Sea. Along the base of the Coast and St. Elias ranges the plateau stands at an altitude of 4,000 or 5,000 feet; it then falls off near the center to 3,000 feet, probablv 

to rise again as it approaches the Rockies.

While these are the general altitudes the plateau surface rises and falls locally. 

In the ramparts of the Yukon, there is a doming which brings the plateau 300 to 

500 feet above the general level, and this is but an example 0 of many irregularities. 

The plateau has in fact a warped surface, with many minor ridges, troughs, domes, 

and basins.

Along a part of its southwestern margin the plateau abuts almost directlv against 

the slopes of high mountain ranges (PL X, J?), and so abrupt is this change from 

the smooth flat summits of the upland to the rugged mountains that it is very suggestive of fault scarps. This sharp transition has been noted by Hayes and by the 

writer (in reports cited) along the northern slopes of the St. Elias Range, and similar 

relations probably prevail along the north base of that part of the Alaska Range 

which fronts on the Tanana Valley, but the west front of this range is so deeply 

buried in a mantle of gravel that the plateau feature is not recognizable.

In the discussion of the structural geology it has been shown that the oldest 

formations of Alaska occur in this province, and that in it probably lies the 

protaxis of the northwestern part of the continent. Paleozoic rocks of various 

horizons are closely infolded and with them occur beds of Upper and Lower 

Cretaceous age. In the Yukon Valley fresh-water sandstones, conglomerates, and 

.shales of Eocene age occur in isolated basins to thicknesses x>f several thousand 

feet, and these are indurated and sometimes closely folded and faulted, the 

deformation representing the last extensive dynamic revolution of this district. 

Miocene'' or Pliocene beds have not been definitely recognized, but are probably 

represented at several localities on the Yukon by some unconsolidated gravels and 

horizontal sands, while silt deposits of Pleistocene age are found along the entire 

length of the valley.

The Eocene beds (Kenai) were deposited and deformed before the erosion of 

the Yukon Plateau surface, and the later Tertiary beds seem to have been

a Brooks, A. H., A reconnaissance of the Cape Nome and adjacent gold fields: Special publication U. S. Geol. Survey, 

pp. 48-64.

ft Ibid., pp. 62-64. 

Collier, A..!., A reconnaissance in northwestern Alaska: Prof. Paper U. S. Geol. Survey No. 2,1902, pp. 38-42.

< Brooks, A. H., Reconnaissance from Pyramid Harbor to Eagle City, Alaska: Twenty-first Ann. Kept. U. 8. Geol. 

Survey, pt. 2, 1900, p. 347.

'iSpurr. J. E., Geology of the Yukon gold district: Eighteenth Ann. Kept. U. S. Geol. Survey, pt. 3, ]898, pp. 87-392.
TOPOGRAPHIC TYPES PLATEAUS. 279

deposited in channels incised in the plateau. This would place the period of 

erosion of the peneplain in the late Eocene or in the Miocene, which corresponds 

in general with the age determination made by Dawson and others.

These facts show that during late Eocene or early Miocene time a large area, 

whose limits will be further discussed, was elevated above sea level, and that 

during a long period of stability which followed it was reduced by erosion to a 

featureless plain which sloped gently toward sea level with some monadnocks 

which stood above the general level. The altitude of these remnants which now 

stand above the plateau surface affords a measure of the minimum amount of 

this erosion. About the middle of the Tertiary this cycle of erosion was terminated 

by a differential elevation which was greatest along the present margins of the 

plateau and was probably both gradual and intermittent. This elevation revived 

the activities of the streams, and the present drainage system was gradually 

developed.

The Anaktuvuk Plateau seems to be even a better example of peneplanation 

than the plateau above described, but its features are known only along Schrader's 

route of travel in northern Alaska. According to his descriptions 3 this plateau 

stretches from the seaward scarp of the Rocky Mountains, where it has an altitude 

of about 2,500 feet northward, for about 100 miles to where it merges into the 

constructional Tertiary plateau at an altitude of 800 feet. For 50 to 60 miles 

from the base of the mountains the plateau is a gently rolling upland, diversified 

by broad, shallow drainage channels. Flat-topped ridges rise several hundred 

feet above the general level, but the aspect of the plateau as a whole, both from the 

descriptions and the photographs, indicates an erosional surface (PI. XXIX, />). 

Collier has recognized what appears to be the same surface of erosion in the flattopped upland, about 1,500 feet high, which stretches inland from Cape Lisburne.

The bed rock includes sediments of Upper and Lower Cretaceous *> age, thrown 

up into broad open folds, and succeeded unconforrnably by slightly indurated 

shales and limestones of Eocene ago, which have suffered some deformation, the 

beds being folded and faulted. These are overlain by unconsolidated Pliocene (?) 

silts, which are entirely undisturbed and probably rest unconformably on the 

Eocene beds. The broad open folds of the Cretaceous strata and the minor 

plications and faults of the lower Tertiary beds are all beveled by the plateau 

surface, which is undoubtedly a plain of erosion, and probably passes with gentle 

dip underneath the constructional plateau formed by the younger horizontal 

Tertiary silts. This seems the most probable explanation, though Schrader's 

hasty exploration could not establish the relation of the planation surface and the 

youngest Tertiary beds. The Anaktuvuk Plateau is then a peneplain which was 

formed in late Eocene or Miocene time and elevated to 2,500 feet at the base of 

the mountains. Its age seems to correspond closely with that of the Yukon Plateau.

The surfaces of the two plateaus described are believed to have been the result 

of denudation under subaerial conditions, but the York Plateau in the Seward 

Peninsula appears to be an elevated plain of marine erosion. The York Plateau c

aSchrader, F. C., Reconnaissance in northern Alaska: Prof. Paper IT. S. Geol. Survey No. 20, 1904, pp. 45-46.

Mbid., pp. 50-97.

( Reconnaissance of the Cape Nome and Adjacent Gold Fields of the Seward Peninsula, p. 52.
280 GEOGRAPHY AND GEOLOGY OF ALASKA.

(fig. i) embraces about 40 or 50 square miles near the extreme western point of the 

Seward Peninsula (PL VI). Its surface, which is about 600 feet above sea level, is 

perfectly smooth, but is interrupted here and there by a few remnants of unreduced 

areas. A broad, rock-cut bench extends the plateau level to the east around the 

southern face of the York Mountains (PI. XXX, A), and is undoubtedly an example 

of the result of marine abrasion. The material produced b}T the wave cutting1 of such 

a small area could easily have been removed by the current sweeping through the 

strait, which probably then as now separates the Seward Peninsula from the Asiatic 

Continent.

CONSTRUCTIONAL PLATKAUS.

Constructional plateaus are of two kinds those of sedimentary and those of 

igneous origin, but the former are of far greater areal extent and phjrsiographic 

importance.

The northern part of the Anaktuvuk is probably built up of horizontally 

bedded late Tertiary sediments, and hence is constructional. To the same type 

belong plateaus which are formed of horizontally bedded Pleistocene sands and 

gravels. Small table-lands of this character are very common as coastal features, 

but only those which lie inland are of sufficient extent to deserve special mention.

CAPE MOUNTAIN. ELEV. 2300 FT. YOR 

OF WALES

FIG. 4. Sketch of the coast from Cape York- to Cape Prince of Wales, showing York Platejm.

The northwestern front of the Alaska Range falls off abruptly to a gravelfloored plateau from 2,000 to 2,500 feet high, which slopes gently to the north and 

has been dissected by the larger streams (PI. XXXII, A). Near the mountains it 

is often covered by glacial erratics and sometimes by moraines. This plain appears 

to have been built up of bedded sands and silts which have already been described 

as glacial overwash deposits.

Of similar character is the Copper River Plateau, which stretches westward 

from the Copper River Valley, meeting the headwaters of the Sushitna. This has 

been described by Mendenhall,a as a great flat upland region which is floored with 

gravel, and near its margin is covered with glacial debris (Pis. XIV, A, and 

XXV, A). So far as known, it is everywhere underlain by gravel, sands, and 

silts, but recent investigations have shown that these in some places mantle Tertiary 

sediments.

Small plateaus of lava type are not uncommon, but are usually of low relief 

and small extent. The plateau at the junction of the Lewes and Pelly rivers is 

formed by a Pleistocene extrusion of lava, and many similar features are found on

"Reconnaissance from Resurrection Bay to Taiiana River: Twentieth Ann. Kept. U. S. Geol. Survey, pt. 7, 1900, 

pp. 297, 316, and 331-335.
TOPOGRAPHIC TYPES LOWLANDS. 281

the lower Yukon. Some of these formed temporary obstructions to stream courses, 

such as at the Miles Canyon on the Lewes (PL XXVI, B). More extensive 

examples occur in the Mount Wrangell region, where Mendenhall and Schrader have 

discovered lava plateaus of considerable extent.

The lowlands fall into two general groups. One embraces the coastal plains, and 

is essentially a constructional type; the other, which will be called the basin lowland, 

is primarily a degradational form.

COASTAL PLAINS.

The coastal plains are very simple land forms, being essentially featureless 

lowlands which stretch along the coast and extend inland for a greater or less 

distance. They are characterized by meandering drainage lines, abundance of lakes 

and monotonous relief, and are often only a few feet above sea level. Their inland 

margin is often bounded by an escarpment.

The coastal plains are, for the most part, the result of alluviation at the mouths 

of larger rivers, which has extended the deltas seaward and, in some instances, has 

been aided by a seaward tilting of the land. Of less extent are the coastal plains 

which were formed by marine benching and subsequent elevation.

Extensive coastal plains occur in northern Alaska, where they border the southern 

Arctic and the eastern coast of Bering Sea. These have been built of fluvial 

deposits, aided in some instances by seaward tilting, and are usually bounded inland 

by a more or less abrupt scarp.

The silted estuary, another type of coastal plain, is well exemplified by the 

lower part of the Sushitna Valley, where a broad lowland extends inland for 150 

miles and stretches eastward so as to include the lower Matanuska drainage, and is 

represented on the west side of Cook Inlet by a slightly elevated plain which reaches 

to the base of the foothills.

BASIN LOWLANDS.

Broad, flat depressions, separated from the encircling highland areas by almost 

unbroken scarps, are a very common topographic type in Alaska, and to these the 

name " basin lowlands" has been given. A basin of this kind always forms a part of 

a drainage system, but is in fact distinct from any valley type. These land forms 

are well illustrated by a typical example in the Fish River Valley, of which a 

contoured map is reproduced in fig. 5. The basin shown has a flat floor, rather steep 

walls, and is drained by the Fish River through a constricted valley with steep 

grade. One of the characteristic features of this lowland type is that within it the 

water courses are sluggish and aggradation is going on, while the comparatively 

narrow channels of -^xit are being rapidly cut down. In the basin of Fish River the 

floor is only about 100 feet above sea level. But there are other examples, the floors 

of which are known to be much higher.

The Yukon Flats (pp. 74-78), with its area of probably 20,000 square miles, is the 

largest of these basin lowlands, but except in size it is in every way similar to the Fish
282 GEOGRAPHY AND GEOLOGY OF ALASKA.

Kiver basin. Similar types occur on Koyukuk and Kuskokwin rivers, and many 

smaller ones have been noted in the Soward Peninsula (PI. XXXIII, A).

The basin lowlands are believed to be due to changes in the cutting power of 

streams brought about by barriers, and in the examples cited these barriers are

Scale

FIG. 5. Upper basin of Fish Kiver, Seward Peninsula, a typical basin lowland.

believed to be warpings of the crust of the earth. It has alreadj' been shown that 

there is evidence of a local doming of the Yukon Plateau at the Ramparts of the 

Yukon. This arch has brought about a local base-level, above which has been cut 

the broad basin called the Yukon Flats. The uplift kept pace with the cutting
LAKES AND COASTAL FEATURES. 283

power of the Yukon, which flows across it, and the base-level conditions abovj e the 

barrier resulted in an accumulation of alluvium.

LAKES.

The lakes of Alaska are probably chiefly of glacial origin, but some, similar 

to the basin lowlands, may have been formed b}^ the damming of drainage channels 

by local warpings. The lakes of glacial origin have been scoured out by ice action 

or dammed by moraines. The many smaller lakes in regions of volcanic activity 

or of glaciation and in the flood plains of rivers will not be here considered.

The largest Alaska lakes. Clark and Iliamna, lie just west of Cook Inlet, and 

are separated from Pacific waters by the northern end of the Aleutian Range. 

They drain southwestward into Bristol Bay, but have not been accurately mapped. 

Spurr" has suggested that lakes Clark and Iliamna may be due to a rock barrier 

caused by a local crustal movement. Lake Iliamna seems, however, up to very 

recent times to have been an arm of the sea, and may owe its origin to the 

damming by river deltas.

Lake Minchumina, tying northwest of the Alaska Range, is probabty of glacial 

origin, for though it is unsurvej'ed it is known to lie close to the northern limit 

of glaciation. Mendenhall * has described a number of large lakes in the upper 

Kobuk Valley and assigned a glacial origin to them. Chandler Lake, at the headof the Colville. in the absence of evidence to the contrary, may also be provisionally 

classed with the glacial lakes.

The origin of Lake Kluane and the lakes lying east and north in adjacent 

regions of Canada is probably closely connected with the extensive changes in 

drainage which have taken place in this region during and since the Glacial epoch. 

The larger lakes through which the Lewes River flows are probably caused by 

local warpings.

COASTAL FEATURES.

In regard to the coastal topography northern and southern Alaska are in 

strong contrast. The Pacific coast line is of great irregularity, being broken by 

innumerable inlets and diversified by many islands, while the mountains often rise 

steeply directly from the water. The coast of Bering Sea and the Arctic Ocean 

is characterized by a monotonous uniformity, with its long, straight beaches and 

gentle inland slopes, often broken by a series of steplike benches which mark 

old sea beaches.

These two types of shore line are usually believed to indicate, respectivety, 

recent elevation and recent depression. The barrier beaches and coastal plains 

show that the land has been elevated relative to the sea, while the deep estuaries 

and broken coast line are interpreted as a depression which has led to invasion 

of the sea.

In northern Alaska there is abundant confirmatory evidence of recent elevation besides the contour of the actual shore line. Along the Bering and Arctic

«Spurr, J. E., A reconnaissance in southwestern Alaska: Twentieth Ann. Kept. U. S. Geol. Survey, pt. 7, 1900, p. 258. 

''Prof. Paper U. S. Geol. Survey No. 10, 1904, pp. 45-48.

17211 No. 45 06 19
284 GEOGRAPHY AND GEOLOGY OF ALASKA.

coast terraces of unquestionable marine origin have been found at many localities 

up to an altitude of 600 feet, and on the Seward" Peninsula some rock-cut 

benches at altitudes of 1,000 to 1,700 are also believed to be wave-cut. The evidence of the depression of the Pacific littoral rests entirely in the contour of the 

coast. It is certain that the fiords of southeastern Alaska seem to have all the 

characteristics of a drowned topography, but Gilbert 6 has pointed out that much 

of the erosion of channels now below tide water was the result of glaciation.

DKAINAGE.

The physiographic history of the drainage is too varied and complex to permit 

any categorical classification, such as has been used for some of the land forms. 

It is proposed, therefore, to here give only a general account of the development 

of some of the larger rivers.

In a broad way, the Yukon, and probably the Kuskokwim, follow directions 

determined by structural lines, and the same may be true of the Noatak and Kobuk 

rivers, whose valleys are parallel to the general trend of the Rocky Mountains. 

Of the Pacific drainage the Sushitna River alone is of this type, for the lower 

courses of the Copper, Taku, and Stikine lie in valleys which are transverse to 

the main lines of height. The streams flowing northward to the Arctic are at 

right angles to the dominant structural lines, but it will be shown that their 

direction was consequent on a line of recent maximum uplift.

The great southwesterly bend of the Yukon is in harmony with the general 

structural features of this part of northwestern America, being parallel to bends of 

the southern coast line, and of the Pacific and Rocky Mountain systems. In a general 

way the Yukon follows the line of minimum uplift of the Yukon Plateau. The 

upper Yukon flows in a rather narrow valley, which makes broad, sweeping curves, 

very similar to the oxbows of a mature drainage system. These curves were probably a heritage from a previous cycle, when the region stood at or near base-level, 

and during subsequent gradual elevation were sunk in the old valley floor. Similar 

curves in the valley of the Yukon occur in the Rampart region. The great bend of 

the Yukon, near the mouth of the Koyukuk, parallel to the coast line, has riot been 

explained, and it may be that at one time the Yukon found a more direct route to 

Norton Sound.

Reference has been made to a system of abandoned valleys which form a series 

of broad depressions stretching parallel to the mountains in the upper Yukon basin. 

These valleys lie in a northwest-southeast direction and belong to an older drainage 

system of which little is known (fig. 6, PL XXXII, B). The writer has suggested 

elsewhere" that these are part of a drainage system tributary to the Alsek, which 

traverses the St. Elias Range and empties into the Pacific. The intermontane portion of the Alsek Valley has not been mapped, but from the descriptions there seems 

to be an old valley floor, possibly 8 to 10 miles in width, below which the river has

t Brooks, A. H., Nome and adjacent gold fields, a special publication IT. S. Geol. Survey, pp. 57-58. Compare Coast 

of Bering Sea and vicinity, by G. M. Dawson: Bull. Geol. Soc. America, vol. 4, 1894, pp. 117-146.

Dawson was the first to recognize the evidence of general elevation in the Bering Sea province.

("Gilbert, G. K., Glaciers and glaciation: Harriman Alaska Expedition, vol. 8, pp. 119-139. New York, 1904.

i Reconnaissance from Pyramid Harbor to Eagle City, Alaska: Twenty-first Ann. Kept. II. S. Geol. Survey, pt. 2, 

1900, pp. 354-355.
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 45 PL. XXXI

WAVE-CUT ROCK BENCH ON SOUTH SIDE OF KING RIVER VALLEY, SEWARD PENINSULA.
U. 8. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 45 PL. XXXII

A. GRAVEL PLATEAU AT NORTHWEST BASE OF ALASKA RANGE.

. VIEW ACROSS DONJEK RIVER, 

Abandoned valley in middle distance.
U. S. GEOLOGICAL SURVEY

PROFESSIONAL PAPER NO. 45 PL,

A. UPPER NIUKLUK BASIN, SEWARD PENINSULA. 

A typical basin lowland.

B. LOWER GORGE OF KOBUK RIVER. 

Draining a basin lowland.
TOPOGKAPHIC TYPES DRAINAGE. 285

incised a channel several hundred if not thousands of feet deep. The older and 

higher valley is interpreted as marking the outlet of the older drainage system which 

has been referred to.

FIG. 6. Sketch map, showing former drainage courses.

The Kuskokwim Valley indicates a maturely developed drainage system, but 

little is known of its history. Below the flats it takes a winding course, making a 

series of right-angled bends, one of which has a striking parallelism to the bend of
286 GEOGRAPHY AND GEOLOGY OF ALASKA.

the Yukon at the mouth of the Koyukuk. An examination of the map (PL XXXIV, 

in pocket) shows that there is also a striking parallelism of parts of the valleys 

of a number of the Yukon tributaries, suggesting a unity of cause, probably of a 

structural character.

The Sushitna Valle3T , broadly speaking, follows the strike of the bed rock. 

Changes of drainage have taken place, which will not here be discussed in detail, 

which have diverted some of its headwater tributaries to the Tanana (see map, 

PI. XI).

Mendenhall r< has stated that a recent uplift has accelerated the cutting power 

of the Matanuska River, which has incised a steep-walled valley in an older floor 

which remains- as a series of benches 200 feet above the water (PI. XV. A). He 

has also called attention to the influence of the recent warpings on the drainage of 

this region.

The history of the Copper, Alsek, Taku, and Stikine rivers is probably alike in 

its broader features, and the details will not here be recounted. These, together 

with the other large rivers of British Columbia, seem to traverse the coastal 

mountain barrier along valleys determined by antecedent conditions. 6 Their lower 

valleys at least have the same direction as before the present coastal mountains were 

elevated, and the streams maintained their courses across the barrier during the 

slow uplift.

Spencer conceives that the Copper River basin is due to headwater erosion of 

the present river, which maintained its course across the uplift of the Chugach 

Mountains. .Mendcnhall's 0 more recent studies of this field lead him to assign a 

structural origin to the Copper River basin that is, that this great depression is a 

"grabon."

CORRELATION OF PENEPLAINS. 

INTRODUCTION.

The matter presented makes it clear that in the correlation of the several 

peneplains lies the key to the entire physiographic history of the province. The 

writer is well aware that in attempting correlations on such fragmentary data he is 

treading on dangerous ground, for the results of surveys now in progress may 

entirely overturn any conclusion arrived at before it can appear in print. He 

believes himself fortunate, therefore, to be able to share the burden of responsibility 

with Spencer, who has already broken the ground for speculations by his very 

suggestive paper entitled "The Pacific Mountain systems in British Columbia and 

Alaska,'''' which contains the first attempt at any general conclusions regarding the 

origin of the physical features of Alaska. What here follows is largely an exposition of Spencer's theory, but with a somewhat broader application.

THE PENEPLAINS.

It will be well to pass in brief review the facts already recited in regard to the 

recognized planation surfaces. In British Columbia the summits of the Coast

« Reconnaissance from Kesurrection Bay to Tanana River: Twentieth Ann, Rept. U. S. Geol. Survey, pt. 7, 1900, pp. 331- 

335.

fi Spencer, A. C., The Pacific Mountain system in Alaska: Bull. Geol. Soc. America, vol. 14, pp. 117-132, 

c Geology of the central Copper River region: Prof. Paper U. S. Geol. Survey No. 41. 

d Bull. Geol. Soc. America, vol. 14, pp. 117-132.
CORBELATION OF PENEPLAINS. 287

Range rise to a uniform altitude of 8,000 to 9,000 feet, but to the north gradually 

decrease in height, and in Alaska stand between 3,000 and 5,000 feet. Though the 

change in altitude is apparently great it is so gradual as not to break the general 

uniformity of summit level. This summit level bears no constant relation to 

structural features, and appears to admit of no other explanation than an elevated 

surface of erosion (PI. XXVIII, ^1).

To the north, and along a part of its inland front, the summit level of the Coast 

Range merges with that of the Yukon Plateau in a way which seems to prove the 

identity of the two peneplains. On the other hand, it has been shown that the Coast 

Range peneplain abuts abruptly against the southern slope of the St. Elias Range. 

The valleys of the Stikine and Taku rivers, as well as those of other streams of 

British Columbia to the south, which lie transverse to the Coast Range, have 

probably inherited their courses from a former mature drainage system which was 

developed on the old peneplain.

The uniformity of summit levels (PI. XXVIII, S>) of the Chugach Mountains, 

which form the coastal barrier of the Copper basin, has been explained by assuming 

that these mountains form an elevated erosional surface which now stands at about 

6,000 feet, with occasional residual peaks rising to 8,000 feet. The same base-level 

finds expression in conformity of altitude of a highland on the south side of the 

Wrangell Mountains, as well as in a general uniformity of summit levels of the 

Skolai Mountains to the north, and probably in the Nutzotin Mountains, where it 

seems less well marked.

This dissected plateau varies in altitude by gradual slopes from 6,000 to 8,000 

feet, while its eastward projection abuts against the, higher mountain mass of the 

main St. Elias Range. The same relation seems to exist between the westward 

extension of the summit level of the Skolai and Nutzotin mountains and the Alaska 

Range, for the latter rises as a rugged mass above the level of the dissected plateau. 

The relation at the north base of the Nutzotin Mountains is less well known, though 

a study of the topographic reconnaissance maps makes it appear at least that here, 

as along the inland slope of the Coast Range, there is a transition between the 

summit level of the Nutzotin Mountains and that of the Yukon Plateau. In any 

event there is no such sharp line of demarcation as between the Yukon Plateau and 

the northern base of the St. Elias Mountains."

The Chugach Mountains are broken by the Copper River, which traverses them 

in a rather sharply cut valley. This drainage course, like the drainage courses 

transverse to the Coast Range, has been explained by Spencer as antecedent, beinginherited from former base-leveled conditions which now find expression in the 

elevated peneplain.

The Yukon Plateau (PI. XXX, B) is the third and by far the most extensive 

of the Alaskan peneplains, and is in fact of the same age as that recorded in 

the Coast Range summits. Its general altitude along the inland front of the Pacific 

Mountains is between 5,000 and 6,000 feet. It has been shown that it merges into the 

Coast Range summit level, abuts abruptly against the northern face of the St. Elias

«It should be noted that the sharp transition between the rugged mountains of the Pacific system and the upland of 

tlie interior, which has been so often emphasized iu descriptions of Alaskan topography, is true only of the St. Ellas and 

Alaska ranges, and along the southern part of the Const Range.
288 GEOGRAPHY AND GEOLOGY OF ALASKA.

Range, possibly merges into the summit level of the Nutzotin Mountains, and that 

there is a sharp line of demarcation between it and the northern front of the Alaska 

Range.

The Yukon Plateau level falls off toward the north and west to less than 2,000 

feet near the Yukon, and probably rises again near the Rocky Mountains in the 

upper Porcupine basin. Sohrader recognized it in the Koyukuk basin, and believes 

it to be sharply differentiated from the Rocky Mountains, though a study of the 

topographic reconnaissance maps hardly bears out this view, for the plateau seems 

to rise gradually toward the summit level of the mountains. A lower peneplain was 

recognized by Schrader and called the Koyukuk Plateau. The following statement 

by Schrader seems to find support in the contoured maps, and points toward a 

gradual transition between planated summits of the Endicott Mountains, the Yukon 

Plateau, and the Koyukuk Plateau, and does not accord with his conclusions:

"The higher level (Yukon Plateau)/8 which also suggests a former plateau, now 

dissected and largely removed by erosion, lies at about 3,000 feet, but is indefinite. 

Its best expression occurs along the base of the mountain, where portions of nearly 

flat-topped ridges, rising gently northward, soon merge into the foothills of the 

mountains, while to the south they become lost in irregular ridges and hills, 

descending to the lower or Koyukuk Plateau."

It thuri seems possible that more detailed studies may here show a gradual 

transition between the plateau and mountain provinces.

The highest level is preserved in uniform summits of the mountains, which 

stand at an altitude of about 5,000 to 6,000 feet, and is believed to mark a peneplain. 

(PI. XXIX, A.) On the north these summits fall off abruptly to a second peneplain, which finds expression in the Anaktnvuk Plateau. (PI. XXIX, J3.) The 

surface of the plateau is a gently rolling upland, which slopes from 2,500 feet at the 

base of the mountains, and 60 miles to the north appears to merge into a constructional plateau of Tertiary (Pliocene 1) sediments.

A careful analysis of the rather fragmentary data of the stratigraphic and 

structural geology already presented goes to show that the Yukon, Coast Range, 

Endicott, and Anaktuvuk peneplains were formed during post-Kenai (Eocene) prePliocene times; in other words, that they appear to be practically of the same 

age. Of the Chugach peneplain there is less definite evidence, but it is certainly 

post-Mesozoic and pre-Pleistocene.

CORRELATION.

The correlation of the southern peneplains the Coast Range, the Chugach, and 

the Yukon has already been suggested by Spencer in the paper cited. The writer 

must confess to having at first maintained considerable skepticism toward this 

correlation. The topographic surveys of recent date in the headwater region of the 

Copper and Tanana rivers, however, appear to indicate a transition between the 

Chugach-Nutzotin and Yukon Plateau peneplains, and seem to lend support to 

Spencers theory, as do also the stratigraphic studies which point toward the conclusion of a synchronism of all of the peneplains recognized in Alaska.

"Reconnaissance in northern Alaska: Prof. 1'aper U. S. Geol. Survey No. 20, ]904, p. 44.
CORRELATION OF PENEPLAINS. 289

Spencer's argument, a which was based almost entirely on the topographic 

evidence, is summarized by him as follows:

"I. The interior and Yukon plateaus of British Columbia, Yukon, and Alaska 

have been previously recognized as uplifted peneplains, and in the Copper River 

region the summits of the high mountains have been described as upraised base-level 

surfaces. It now appears that the uniform summits which are found over the greater 

portion of the Pacific Mountain system in the north are also representative of 

elevated peneplains which have suffered deep dissection.

"II. The peneplains of the different portions of the coastal mountains and the 

inland plateaus can be correlated one with another. The antecedent nature of the 

rivers which cross the present coastwise barrier demonstrates the identity of the 

ancient erosion surfaces throughout the region outlined.

"III. The Pacific province was raised after the production of the peneplain by 

erosion extending through Eocenei time, mainly through uplifts of a continental 

character. Regional elevation was accompanied by warping, flexure, or displacement, raising tectonic blocks which have been effaced by subsequent erosion, but 

there has been no mountain building due to tangential compression."

Spencer's contention then is that the Pacific Mountain system of Alaska, with 

the exception of the Alaska and parts of the St. Elias ranges, was planated at the 

same time with the Yukon Plateau, and the present relief is largely due to subsequent 

differential uplift.

It has been indicated by Schrader that the summits of the Endicott Mountains of northern Alaska also mark a planation surface which he believes to be 

of the same age as the Chugach peneplain but older than the Yukon peneplain. 

In other words, Spencer recognizes but one extensive peneplain in the portion 

of the Alaskan cordillera considered by him, while Schrader believes there must 

be two distinct surfaces. One objection to Schrader's interpretation of these 

features lies in the improbability that any remnants of an older peneplain should 

be preserved during the long period of erosion while the second was being cut, 

for it must be remembered that the second erosion level has been traced through 

an area 500 by 2,000 miles in extent. If there were two peneplains it would 

be expected that the younger would be cut only in the soft strata and the older 

recorded in the more durable rocks, but nothing of this kind has been noted. 

Moreover, this older period of planation must have been pre-Eocene in age, and 

would have been distorted if not entirely destroyed by the marked epoch of deformation which is known to have taken place throughout Alaska in post-Eocene 

times. It seems at least improbable that any pre-Eocene land surface should still 

be preserved.

A logical extension of Spencer's correlation of the peneplains noted in the 

Chugach Mountains, Coast Range, and Yukon Plateau would include the peneplain of the Endicott Mountains, and even that represented by the Anaktuvuk 

Plateau. The little that is known of the geology of the Arctic Slope region 

points toward such a correlation, though it is evident that it is impossible now

a Bull. Oeol. Soc. America, vol. 14, p. 132.
290 GEOGRAPHY AND GEOLOGY OF ALASKA.

to give it any more weight than that of a working hypothesis. If the Anaktuvuk and Endicott peneplains are identical in age, there must have been a 

sharp flexure or fault at the northern front of the mountains during or subsequent to the uplift which brought the plateaus in their present position.

RECENT GEOLOGIC HISTORY. 

INTRODUCTION.

In the foregoing pages the chain of geologic events from the earliest stratigraphic records has been passed in brief review, the topography has been described, 

and the genesis of its dominant types has been discussed. It remains to present a 

summarj' of the recent geologic history, and thus outline the development of the 

existing land forms, as far as the evidence at hand will permit. Many of the details 

of the topographic evolution will necessarily be entirely neglected. Briefly stated, 

the topography is believed to be the result of the following succession of events, 

which, for the sake of brevity, will be presented categorically.

1. Some time in the late Jurassic or early Cretaceous there was a dynamic 

revolution which seems to have affected the entire province, and can be conveniently 

taken as the beginning of the recent geologic history. At the close of the disturbance much of Alaska was above the sea and a long cycle of degradation began. 

Volcanic vents opened in the Alaska Peninsula and in the Wrangell Mountains.

2. A partial submergence followed during Upper Cretaceous time, and the sea 

invaded the lower Yukon and Kuskokwim regions, the Arctic Slope province, and 

probably a part of the Pacific littoral. This submergence in certain districts 

continued well into the Eocene. The Eocene deposition was in part in open ocean, 

in part in embayments, and in part probably in lakes.

3. Sedimentation was terminated late in the Eocene or early in the Miocene by 

an uplift accompanied by widespread deformation. After this disturbance Alaska 

had about its present shore line, and its two mountain systems were probably 

marked by areas of considerable relief. A long period of relative stability followed, 

during- which a large part of the province was reduced to a peneplain. At the close 

of this cycle some kind of a mountain barrier was probably left along the present 

St. Elias Range and this was bisected by the ancestor of the Alsek River. Volcanism 

continued in the Wrangell and Alaska Peninsula regions.

4. In late Pliocene or early Pleistocene time the region was again elevated by 

an uplift, differential and probably intermittent, to about its present altitude, and 

the previously developed peneplain was deeply dissected. The Yukon drainage 

system was developed in part along lines determined by the previous base-leveled 

conditions. The Alsek, Stikine, and other southerly flowing rivers maintained their 

courses across the coastal mountain barriers, which had been uplifted to a greater 

altitude than the interior province. At the same time the Noatak and Kobuk valleys 

were incised in a general way following bed-rock structures. Volcanism continued 

in the Wrangell and Aleutian mountains.

5. The elevated tracts throughout the province became the gathering grounds of 

glaciers, which moved down the slopes, filled up the valleys, and in many instances
RECENT GEOLOGIC HISTORY. 291

stretched out into the lowlands far beyond the mountain slopes. In southeastern 

Alaska the great cordilleran glacier scoured out the preexisting vallej's.

The ice subsequently retreated and the accompanying floods filled the valleys 

and lowlands with extensive alluvial deposits, in which were mingled Pleistocene 

organisms. Gradually, as the waters became less burdened with sediments, they 

began to erode and trenched the extensive mantle of overwash, a process which is 

still going on.

There is evidence that during Pleistocene times there were many local elevations 

and depressions and some of them have affected the drainage systems.

CONDITIONS ANTERIOR TO UPPER CRETACEOUS TIMES.

It is known that deformation and metainorphism took place in recurrent epochs 

during Paleozoic and early Mesozoic times, but these influenced the development of 

the present land forms only so far as they determined lines of weakness along which 

erosion was subsequently active. The last of these disturbances of sufficient intensity to produce any considerable metamorphism, deformed rocks of late Jurassic or 

early Cretaceous age. " This movement of the earth's crust seems to have been farreaching, for its influence has been observed in the Lower Cretaceous terranes 

throughout Alaska. Its intensity varied greatly, for in one locality, as on the 

upper Yukon, the strata of this age were closely folded and more or less metamorphosed; while in another, in the Copper* River basin, they were only indurated, 

uplifted, and slightly deformed. This epoch of disturbance will be chosen as the 

starting point of the discussion of the recent history of the region, for it seems to 

have been the first to have directly influenced the development of the topography.

At the close of this disturbance much of the province was uplifted above the 

sea, and erosion began on the newly disclosed land surface. During this period of 

degradation volcanism first became active since Paleozoic time in the Copper c River 

region, and probably was also revived in the Aleutian Range.

There is no measure of the duration of this cycle of erosion, but in the Copper 

River basin at least it seems to have continued a sufficient length of time to reduce 

the land nearly to base-level. It seems probable that some parts of the province 

remained exposed to atmospheric agencies much longer than others, for in some 

places the Upper Cretaceous rests on the Lower Cretaceous; in others the former is 

absent and the latter are directly overlain by Eocene beds. The evidence of this 

deformation and subsequent erosion is found in the marked unconformity between 

the Lower Cretaceous and overlying Mesozoic or Eocene sediments which have been 

noted throughout the province.

LATE CRETACEOUS AND EARLY EOCENE DEPOSITION.

A gradual submergence of a part of the province terminated the period of 

erosion and inaugurated sedimentation. In southeastern Alaska, in lower Yukon 

and Kuskokwim valleys, and in the Arctic Slope province the deposition began during

iThe tratigraphic position of the AuceHa-Tje&nng beds of Alaska is still in some doubt, but they are here classed 

as Lower Cretaceous.

t> Geology and Mineral Resources of a Portion of the Copper River District, p. 51. 

cOp. cit., p. 51.
292 GEOGRAPHY AND GEOLOGY OF ALASKA.

Upper Cretaceous times and continued without interruption through a part of the 

Eocene. The fragmentary nature of the evidence" makes it impossible to determine 

what part of Alaska was submerged during this epoch, but it is probable that the 

transgression of the sea in Upper Cretaceous times was gradual from the southwest 

and extended as far inland as the mouth of the Porcupine. Dawson* has suggested 

that during the Laramie times (Upper Cretaceous) much of the lower Yukon basin 

was occupied by the sea, and the stratigraphic studies of Collier 0 would confirm this 

in part at least. He found marine Upper Cretaceous beds on the lower Yukon, 

succeeded by Eocene beds with conformable relations. As these latter are chiefly 

fresh-water deposits and of a coarse character, such as conglomerate and sandstone, 

it is fair to presume that they were laid down in embaj^ments or estuaries. These 

beds of Eocene age are found on the Yukon near the international boundary, which 

makes it probable that deposition was going on throughout the Yukon Valley below. 

It is possible, however, that the fresh-water beds are in part of lacustrine origin, 

and there is no definite evidence that the invasion of the Tertiary sea extended above 

the mouth of the Tanana. Indurated sandstones of Upper Cretaceous or Eocene 

age were observed by the writer as far east as the head of the Cantwell, a southern 

tributary of the Tanana. The surveys in the Copper River region have failed to 

reveal any Upper Cretaceous sediments, but some Eocene beds have been found and 

the Wrangell volcanoes had at this time long been active.

Schrader'' has described marine Upper Cretaceous fossils in a sandstone shale 

series overlain by Eocene beds north of the Rocky Mountains, and presented less 

definite evidence of the occurrence of this horizon on the south slope of the 

mountains. His results suggest at least that these deposits may have been laid 

down in seas separated by a barrier. Some Upper Cretaceous sediments have been 

found in the Pacific littoral, which indicate that a part of this district was submerged 

early in this cycle.

The facts indicate that during late Cretaceous and early Eocene times deposition was going on in western Alaska, probably in part in what was open ocean, in part 

in an embayment, and in part in lakes. During this long period there were probably recurrent vacillations of the land mass, which brought about repeated changes of 

shore line. It seems probable that there was then a land area in the present region 

of the Rocky Mountains and another east of the one hundred and forty-first meridian, 

but with the gradual elevation begun in Eocene times the sea retreated toward the 

present coast line of Bering- Sea.

UPLIFT AND PLANATION (LATE EOCENE OR MIOCENE).

About the close of the Eocene there was a gradual uplift throughout the 

province, which, though of an orographic character, was accompanied by considerable local disturbance of the Eocene beds.

The date of this uplift, though in doubt, is probably late Eocene or early 

Miocene times. Dawson e refers this orogenic movement to the Eocene, but if the

«The Upper Cretaceous and Tertiary succession in Alaska is as yet imperfectly known.

b Late physiographical geology of the Rocky Mountain region: Trans. Royal Soc. Canada, 1890.

a Collier, Arthur J., The coal resources of the Yukon: Bull. U. S. Geol. Survey No. 218.

d Schrader, F. C., A reconnaissance in northern Alaska: Prof. Paper U. S. Geol. Survey No. 20, pp. 79-83.

e Geological record in the Rocky Mountain region of Canada: Bull. Geol. Soc. America, vol.12, p. 79.
UPLIFT AND PLANATION. 293

identification of the upper Eocene beds in the lower Yukon basin, deformed at this 

period, is trustworthy it would show that the dynamic revolution took place 

somewhat later. Further evidence on this point is afforded by some unconsolidated beds which have been found on the Yukon below the mouth of the Tanana, 

which are practically undisturbed, and must have been laid down since this period 

of deformation. As these are Miocene or Pliocene, they go to prove that the 

movements were pre-Pliocene and possibly of pre-Miocene, and as this is in general 

accord with the other evidence they can be regarded as marking the close of the 

Eocene.

It seems probable that this elevation affected all of Alaska and exposed a land 

mass of considerable relief, with a shore line not essentially different from that which 

now exists.

Degradation began on the exposed land mass, and during a long period of stability 

which followed an area including hundreds of thousands of square miles was reduced 

to a peneplain. The limits of this planation surface have been discussed in full, but 

it must be understood that whatever may be the correlations of the higher plains 

there can be no doubt that the Yukon Plateau, the British Columbia Plateau, and 

the Coast Range were base-leveled during this epoch. The evidence which suggests 

the synchronous origin of the Chugach, Endicott, and Anaktuvuk peneplains has been 

presented, and for the purposes of this exposition this will be accepted as proof.

Whatever then may have been the history of the bordering mountain systems, 

a large part of the central region at least was reduced to a peneplain during 

the epoch of erosion which followed the late or post-Eocene deformation. The 

resulting plain sloped generall}' gently toward the sea, and occupied the larger 

part of what is now the Yukon basin. Here and there the featureless lowland 

was broken by a mountain or peak which rose above the general level.

The ancestor of the present Yukon was among the rivers which meandered 

across this lowland, with the tortuous courses characteristic of base-leveled conditions, and it probably occupied very much its present course from the junction 

of the Pelly and Lewes to the sea. Only a part of the present drainage of the 

Yukon flowed to Bering Sea, for some found outlet to the Pacific by a river 

which followed the course of the present Alsek. This stream appears to have 

bisected a low mountain barrier which occupied the present position of the St. 

Elias Range. According to Spencer, another river reached the sea along the 

valley of the present Copper. As the planated surface extended across the present Coast Range, there was there no coastal barrier. The drainage was carried to 

the Pacific by the Taku, Stikine, and other rivers, which during the subsequent 

uplift, like the Alsek, maintained their valley to the Pacific across a gradually 

rising barrier. In northern Alaska the peneplain swept across the present Rocky 

Mountains and stretched northward to the Arctic, where the base-level was 

extended seaward by the constructional surface formed of late Tertiary sediments.

At the close of this extensive period of denudation central Alaska had probably the contour of a broad shallow trough, whose sides sloped gently from the borders to an axial line. A broad flat watershed probably separated the western trough 

from the northerly flowing Arctic drainage, and another similar divide may have 

intervened between the Bering and Pacific drainage somewhere in what is now 

northern British Columbia. This divide appears, however, to have been broken by 

drainage courses.
294 GEOGRAPHY AND GEOLOGY OF ALASKA. 

DIFFERENTIAL ELEVATION AND EROSION.

A gradual elevation of the entire land mass closed the long period of stability 

when this extensive planation took place. The trough-like form of central Alaska 

was emphasized by the uplift, which was greater at the margins than at the axis of 

the trough, forming a broad, shallow depression between two lines of height which 

corresponded in a general way with the position of the present Yukon Valley.

The fact that the several rivers which flowed into the Pacific across that part of 

the peneplain which is now marked by the Coast Range maintained their courses 

shows the uplift to have been very gradual. The tortuous character of the Yukon 

Valley in the Ramparts and above the Flats is interpreted as being- the incised meanders of the previous base-leveled conditions, and also points toward slow elevation.

Coordinate with the increased relief river and stream valleys were incised and a 

drainage system developed, much of which was probably along the lines determined 

by the preceding lowland condition. It has been indicated that the course of the 

Yukon was not very different from what it is now. Its great southwest bend 

appears to have been consequent upon the contour of the uplifted area, a feature 

partly inherited from the configuration of the lowland areas and in part induced by 

differential uplift.

It seems well established that a part of the southern drainage of the upper Yukon 

then found an outlet to the Alsek, whose basin included a valley now represented 

by a series of broad northwest-southeast depressions lying southeast of the one 

hundred and forty-first meridian and south of Yukon River (fig. 6). These indicate 

a well-developed drainage system tributary to the Alsek, which at that time must 

have included the upper part of White and Tanana valleys, as well as several of the 

southern tributaries of the Lewes and upper Yukon rivers. It seems probable 

that the broad northeast-southwest depressions extending southward into British 

Columbia have had a similar history, and mark the position of a drainage system 

tributary to rivers emptying into the Pacific through transverse vallej's.

The differential uplift was greatest along the margins of the province, and these 

differences in places brought about sharp flexures or possibly faults. In British 

Columbia, for example, there is a difference of several thousand feet in the summit 

level of the Coast Range and of the Yukon Plateau. This flexure or fault finds 

topographic expression in the steep front vhich the Coast Range presents toward 

the plateau.

If the correlations of peneplains be accepted, there are many similar examples in 

Alaska, of which the most striking is the escarpment marking the Rocky Mountain 

front toward the Arctic. Here the mountains descend abruptly from an altitude of 

about 5,000 feet to the Anaktuvuk Plateau (2,500 feet). Later movements m&y 

have taken place along the same lines, but it seems probable that the escarpments 

are in a large measure due to the differential character of the initial uplift.

Attention has been directed to irregularities of the surface of the Yukon 

Plateau. This also may in part be due to the irregularities of the initial elevation, 

though they are also accounted for by subsequent deformation of the peneplain. 

Stratigraphic evidence of recent deformations is found in the Pleistocene deposits, 

which in some places show broad plications. Of greater import is the evidence of
THE GLACIAL EPOCH. 295

extensive uplift and probable fracture along the western front of the St. Elias 

Range, where Russell" found Pleistocene fossils in unconsolidated beds 5,000 feet 

above sea level.

There is also physiographic evidence of recent minor deformation in the 

plateau region, as well as in the Seward Peninsula. Near Rampart, on the Yukon, 

the plateau surface shows a marked doming, and this is believed to have caused 

the erosion of the broad basin above, known as the '"Yukon Flats." It appears 

that there has been here a local base-level during the period while the Yukon 

was channeling out its valley through the uplift athwart its course. Such local 

domings may account for some of the other lowlands and even lakes of Alaska 

and adjacent portions of Canada. Evidence of recent deformations in the Seward 

Peninsula is found in the general character of the coast line and in the warped 

marine benches, which have been fully discussed* elsewhere.

The Aleutian Range and Wrangell Mountains have been ascribed to extravasations of volcanic material which took place after the last stage of deformation, 

and probably during and subsequent to the abrasion of the peneplain. The date 

of the beginning of the volcanic activity has not been determined, but it is safe to 

say that it was post-Eocene and it has continued up to the present time. In these 

mountains erosion has lagged far behind the upbuilding, hence their present high 

relief.

The uplift was probably not a single movement, but the total effect is the 

result of a number of recurrent elevations, interrupted by periods of stability. 

Nor was the movement necessarily all upward, for the land may have oscillated, 

but the algebraic sum of these disturbances was elevation. These orographic 

movements have left records in the topography, but are not yet sufficiently well 

known to be correlated, and will not here be discussed.

INFLUENCE OF GLACIAL EPOCH ON TOPOGKAPHY.

Glaciatijn in the larger part of Alaska was of limited extent, and except in 

the panhandle had no very marked effect upon the topography, but it contributed 

a large amount of material, which formed extensive overwash deposits bej^ond the 

limits of the ice.

The cordilleran glacier, uniting with the ice from the Coast and St. Elias 

ranges, effectually blocked the channels of the southward flowing streams, such as 

the Alsek, and their drainage was for a time diverted to the Yukon. It has been 

shown elsewhere c that probably one of the effects of this ice blockade was thus 

to divert some of the former drainage of the Alsek to the Tanana and White 

rivers. This same cordilleran glacier traversed the valleys transverse to the Coast 

Range, and uniting with the local glaciers covered the greater part of southeastern 

Alaska and the adjacent islands. It has been indicated that probably much of the 

erosion of the fiords and channels of this coast may have been brought about by

«Russell, I. C., Expedition to Mount St. Elias: Nat. Geog. Mag., vol. 3, 1891, pp. 170-175.

''Brooks, A. H., A reconnaissance of the Cape Nome and adjacent gold fields of Seward Peninsula, Alaska, in 

1900: U. S. Geol. Survey, 1901, pp. 56-62.

Collier, A. ,T., A reconnaissance of the northwestern portion of the Seward Peninsula, Alaska: Prof, Paper U, S. 

Geol. Survey No. 2, 1902, pp. 34-42.

c Brooks, A. H., Reconnaissance from Pyramid Harbor to Eagle City: Twenty-first Ann. Kept. U. S. Geol. Survey, pt. 

2, 1900, p. 354.
296 GEOGRAPHY AXD GEOLOGY OF ALASKA.

ice erosion when the land stood at about its present level. According to Gilbert,® 

the flooded shore line is due rather to this glacial erosion than to an extensive 

depression, and the glacial scouring followed the channels of an older drainage 

system.

Other districts afford nothing to compare with southeastern Alaska for extent 

of glacial erosion, except possibly the irregularities of shore line of Prince William 

Sound. In all the higher ranges, where there has been ice accumulation, cirques 

and U-shaped valleys are typical topographic forms, but these are regarded as 

comparatively slight modifications of a preexistent topography.

The overwash deposits of the glacial epoch embrace the silts which are found 

in the entire length of the Yukon Valley, the gravel plateaus in the upper Kuskokwim basin, as well as on Cook Inlet, together with many deposits of lesser 

extent. After the ice disappeared the streams gradually lost their burden of 

glacial debris, soon began actively cutting the aggradational surfaces, and the 

remnants remain as silt and gravel bluffs along the walls of the present valleys.

In previous reports the author had advocated the view of a marked postGlacial uplift, but he is now inclined to interpret the terraces as the result of 

changes in the erosive powers of the streams. It is impossible, however, to deny 

that some uplift has taken place since the retreat of the ice, for even in southeastern Alaska, where the topography suggests a depression, marine benches have 

been found 200 feet above the present sea level, and in other districts the evidence 

all points toward elevation. It seems then probable that there has been and now 

is a general upward movement relative to sea level throughout the interior and 

in northern Alaska. Of this there is undeniable evidence in the terraces and 

marine benches along the shores of both the Arctic Ocean and northern Bering 

Sea. The retreat of the several ice sheets and the deposition and incision of their 

overwash material left the topography essentially in its present form.

DESCRIPTION OF TOPOGRAPHIC MAP OF ALASKA. 

By R. U. GOODB.

Prior to 1898 knowledge of the geography of the interior of Alaska useful 

for map-making purposes was fragmentary, being practically confined to information derived from a few reconnaissance expeditions sent from time to time, for 

various purposes, by different branches of the United States Government. In 

the year above mentioned systematic geographic and topographic work was 

commenced by the United States Geological Survey, and has been uninterruptedlyprosecuted during the field seasons from 1898 to 1902, inclusive. As a result of 

the above work the following maps have been published or are in course of 

publication:

E. 0. BARNABD. Portymile quadrangle; scale 1:250,000. 

E. C. BABNABD. Cape Nome and adjacent gold fields; scale 1:250,000. 

ROBERT MULDROW. Sushitna River and adjacent territory; scale 1:625,000.

W. S. POST. Region from head of Cook Inlet to Kuskokwim River and down the Kuskokwim to 

Bering Sea, Bristol Bay, and a part of Alaska Peninsula; scsile 1:625,000.

" Gilbert, G. K., Glaciers and glaciation: Harriman Alaska Expedition, vol. 3, 1904, pp. 134-139.
TOPOGEAPHIC MAP. 297

WALTER C. MENDENHALL. Head of Cook Inlet to the Tanana via Matanuska and Delta rivers,

also part of Kenai Peninsula; scale 1:625,000.

Lieut. P. G. LOWE, EMIL MAHLO, and F. C. SCHRADEK. Copper River region; scale 1:376,000. 

EMIL MAHLO. Prince William Sound and vicinity; scale about 1:376,000. 

W. J. PETERS. Portion of Tanana and White rivers; scale 1:625,000. 

W. J. PETERS. Routes from Lynn Canal via headwaters of White and Tanana rivers to Eagle

City; scale 1:625,000.

VV. J. PETEKS. Norton Bay region; scale 1:625,000. 

W. J. PETEKS. From Koyukuk River to mouth of Colville River, including John River; scale

1:625,000.

W. J. PETEKS. The Juneau special district; scale 1:62,500. 

T. G. GERDINE. Portions of Koyukuk and Chandlar rivers; scale 1:625,000. 

T. G. GERDINE. Northwestern part of Seward Peninsula; scale 1:250,000. 

T. G. GERDINE. Upper Copper and Chistochina rivers; scale 1:250,000. 

T. G. GERDINE. Fairbanks and Birch Creek districts; scale 1:250,000. 

T. G. GERDINE. Yukon-Tanana region; scale 1:625,000. 

T. G. GERDINE. Nome special; scale 1:62,500. 

T. G. GERDINE. Grand Central special; scale 1:62,500.

T. G. GERDINE and D. C. WITHERSPOON. Chitina and lower Copper River regions; scale 1:250,000. 

ALFRED H. BROOKS. Sketch maps of York and Kugruk regions. 

D. L. REABURN. From Fort Yukon to Kotzebue Sound, including Call, Alatna, Kanuti, and Koyuk

rivers; scale 1:625,000.

D. L. REABURN. Mount McKinley region; scale 1:625,000.

D. C. WITHERSPOON. Headwaters of Copper, Nabesna, and Chisana rivers; scale 1:250,000. 

D. C. WITHERSPOON. Northeastern part of Seward Peninsula; scale 1:250,000. 

IX C. WITHEHSPOON. The Seventymile and Circle region; scale 1:250,000. 

ARTHUR J. COLLIER. The Cape Lisburne region; scale 1:625,000. 

L. M. PHINDLE and F. L. HESS. Sketch map of Rampart region; scale 1:625,000.

The map of Alaska is principally based upon the above maps, but other 

available maps have been consulted and drawn upon for information, especially 

those published by the Coast and Geodetic Survey, from which the entire coast 

line has been taken, as well as those by the Army, the Navy, the Revenue-Marine 

Service, and the Russian, British, and Canadian governments. When exact cartographic data were lacking, the compiler has been forced to rely on such information as has been collected by the Geological Survey parties from prospectors, 

traders, and natives. The different sections of the map therefore have very 

unequal value, for it is in part based on accurate surveys, in part generalized 

from verbal descriptions and sketch maps. In every case the most reliable source 

of information has been used, and though the map will be subject to many 

corrections in the future, the demand for a general map of Alaska has been so 

great as to justify the publication of one based only in part on accurate 

mensuration.

There are many general maps of Alaska, but none of them show anything 

except the horizontal relationships. The map published herewith embodies the 

first attempt to represent the vertical element, or in other words to show the 

inequalities of the surface. For this purpose contour lines are used, which appear 

on the map in brown. Each contour line passes through points which are 

supposed to have the same altitude, that is, if one would follow a contour on the 

ground he would go neither uphill or downhill, but on a level, the line of the 

sea coast at mean tide being the zero contour. The first contour line indicated
298 GEOGRAPHY AND GEOLOGY OF ALASKA.

on the map is that which would be the coast if the sea were to rise 1,000 feet. 

When the contours are far apart or close together gentle or steep grades are 

respectively indicated, and thus the slopes of the plains and the shapes of the 

mountain masses are shown within the limits of the contour interval employed, 

which is 1,000 feet. For convenience in reading the maps every fifth contour is 

accentuated, those corresponding to 5,000, 10,000, 15,000, and 20,000 being drawn 

with a heavier line than that employed for the intermediate contours.

The map was compiled for the most part by Mr. E. C. Barnard, but material 

assistance was rendered by Messrs. W. J. Peters, T. G. Gerdine, D. L. Reaburn, 

D. C. Witherspoon, F. C. Schrader, W. C. Mendenhall, Arthur J. Collier, and 

Alfred H. Brooks, who have been engaged in the Alaskan geologic and topographic 

work. Mr. A. F. Hassin assisted in the drafting.

It was originally planned to include in this publication an exhaustive catalogue 

of Alaskan maps and such a task was begun, but it was found that owing to the great 

number of recent accessions the preparation of the catalogue involving as it will 

some 1,500 or more entries of maps in various languages required so much time 

that it was concluded that a corresponding delay in the issuance of the map of Alaska 

would not be justified. Moreover, the catalogue is considered to be of sufficient 

importance to warrant its presentation as a separate publication. Work is progressing on the catalogue as rapidly as circumstances will allow.

PUBLICATIONS ON ALASKA AND ADJACENT REGIONS.

There has been no bibliography of Alaska compiled since the exhaustive one by 

Dall and Baker", which was published in 1879. The following list of works on 

Alaska makes no pretense at being complete, but it includes all the reports consulted 

in the preparation of this report, and, it is believed, will form a convenient catalogue 

of the more important publications relating to the geology, geography, and development of Alaska. Publications relating to the fisheries, botany, zoology, or 

ethnology, and many short papers relating to mineral resources, have, as a rule, 

been omitted. With a few exceptions all of the works listed are in the English language. It has been the intention to make this a fairly complete list of the United 

States Government publications relating to Alaskan surveys. Purely administrative 

reports on surveys and investigations have, however, for the most part been omitted.

ABERCROMME, W. R., and GLENN, EDWIN F. Reports of Explorations in the Territory of Alaska, War 

Department, Adjutant-General's Office, No. 25, 1899, pp. 464. (Maps.)

 Copper River Exploring Expedition, 1899. Washington, 1899. Washington, War Department, 1900. pp. 561-626. (Maps.)

ALLEN, Lieut. HENRY T. Glaciation of Alaska. Glacial action in Copper River: Science, vol. 8, 1886, 

pp. 145-146.

 An Expedition to the Copper, Tanana, and Koyukuk Rivers, in the Territory of Alaska, 1885.

Washington, 1887, pp. 1-172. (Maps.)

ANONYMOUS. Scientific expedition to Alaska: Lippincott's Mag., Nov., 1868, pp. 467-485. 

AUSTIN, 0. P. Commercial Alaska in 1901. Summary of Commerce and Finance for May, 1902,

pp. 3937-4038. 1902. (Maps.)

a Dall, W. H., and Baker, Marcus, Partial list of books, pamphlets, papers in serial journals, and other publications on 

Alaska and adjacent regions: Pacific Coast Pilot, Appendix I, U. S. Coast and Geodetic Survey, Coast and Islands of 

Alaska (second series), pp. 225-374.
PUBLICATIONS ON ALASKA AND ADJACENT RKGIONS. 299

BAKEH, MARCUS. Alaskan geographic names. In Twenty-first Ann. Rept. U. S. Geol. Survey, pt. 2, 

1900, pp. 487-509.

 Geographic dictionary of Alaska: Bull. LT . S. Geol. Survey No. 187, 1902, pp. 1-446. 

BALCH, THOMAS WILLING. The Alaskan Frontier. Philadelphia, 1903. pp. 1-198. (Maps.) 

BANCROFT, HERBERT HOWE. History of Alaska, 1730-1885. San Francisco, 1886. pp. 1-775. (Maps.) 

BARXABD, E. C. Report of the Fortymile expedition. Maps and descriptions of routes of exploration in Alaska in 1898, with general information concerning the Territory: U. S. Geol. Survey,

1899, pp. 76-84. (Map.) 

BECKER, GEORGE F. Reconnaissance of the gold fields of southern Alaska, with some notes on the

general geology: Eighteenth Ann. Kept. U. S. Geol. Survey, pt. 3, 1898, pp. 7-86. (Maps.) 

BEBCIIEY, Capt. FKBDERIC WILLIAM. Narrative of a Voyage, to the Pacific and Bering Strait, to cooperate

with the polar expeditions, performed in H. M. S. Blossom, in the years 1825-1828. 2 parts.

XXIII, 392 pp.; VIII, 393-742 pp. 3 maps, 23 pi. 1831. 

BOWMAN, AMOS. Geology of the mining district of Caribou, British Columbia: Ann. Bept. Geol.

Nat. Hist. Survey Canada, new ser., vol. 3, pt. 1, pp. 66A-69A. 1888. (Maps.) 

BREWER, W. T. The Ketchikan mining district, Alaska: Engineering and Mining Journal, Nov. 16,

1901, p. 630. (Maps.) 

BROOKS, ALFRED H. The coast from Point Barrow to the Mackenzie. Maps and descriptions of routes

of exploration in Alaska, in 1898, with general information concerning the Territory: U. S. Geol.

Survey, 1899, pp. 130-131. (Maps.)

 The Yukon district. In maps and descriptions of routes of exploration in Alaska, in 1898, 

with general information concerning the Territory: U. S. Geol. Survey, 1899, pp. 85-100. (Maps.)

 Reconnaissance from Pyramid Harbor to Eagle City, Alaska: Twenty-first Ann. Rept. U. S. 

Geol. Survey, pt. 2, 1900, pp. 331-391. (Maps.)

 Reconnaissance in the Tanana and White river basins, Alaska, in 1893. In Twentieth Ann. 

Rept. U. S. Geol. Survey, pt. 7, 1900, pp. 425-494. (Maps.)

An occurrence of stream tin in the York region, Alaska: Mineral Resources TJ. S. for 1900,

U. S. Geol. Survey, 1901, pp. 267-271. Published also as a separate. Washington, Government 

Printing Office, 1901. Cover and pp. 1-5.

 The coal resources of Alaska: Twenty-second Ann. Rept. I*. S. Geol. Survey, pt. 3, 1901, pp. 

515-571. (Map.)

 The placer gold fields of the Nome region: Mining and Metallurgy, vol. 24, 1901, pp. 249-252. 

(Map.)

 Northwestern America and northeastern Asia. A Criticism: Science, vol. 15, 1890, pp. 909-910.

 Geological reconnaissance in southeastern Alaska: Bull. Geol. Soc. America, vol. 13, 1902, 

pp 253-266. (Map.)

 Proposed surveys in Alaska in 1902: Nat. Geog. Mag., vol. 13, 1902, pp. 131-134. (Map.)

 The copper deposits of the White, Tanana, and Copper River regions, Alaska: Engineering and 

Mining Jour., vol. 74, 1902, pp. 13-14. (Map.)

 Preliminary report on the Ketchikan mining district, Alaska, with an introductory sketch of 

the geology of southeastern Alaska: Prof. Paper U. S. Geol. Survey No. 1, 1902, pp. 1-120. 

(Map.)

 Placer gold mining in Alaska in 1902: Bull. U. S. Geol. Survey No. 225, 1903, pp. 41-48.

 A reconnaissance in the Mount McKinley region, Alaska: Science, vol. 16, 1902, pp. 985-986.

 - Stream tin in Alaska: Bull. I'. S. Geol Survey No. 225, 1903, pp. 92-93.

 Placer gold mining in Alaska in 1903: Bull. IT. S. Geol. Survey No. 225, 1904, pp. 43-59.

 An exploration to Mount McKinley, America's highest mountain: Jour. Geog., vol. 2, 1903, 

pp. 441-469. (Map.) Reprinted in Smithsonian Report, 1903, pp. 407-425.

 The mining industry in Alaska: Eng. Min. Jour., vol. 77, 1904, pp. 75-78. (Map.) Reprint 

in Mineral Industry, 1903, New York, 1904, pp. 420-428.

 The geography of Alaska illustrated by a new map: Nat. Geog. Mag., vol. 15, 1904, pp. 213- 

219. (Map.)

 The investigation of Alaska's mineral wealth: Trans. American Inst. Min. Eng. Lake Superior 

meeting, Sept., 1904, pp. 1-20. (Map.) Reprinted in Am. Geog. Soc. Bul., vol. 37, pp. 26-40. 

1905. Another reprint in Appendix to Report of Governor of the District of Alaska, 1904. Washington, pp. 95-105.

17211 No. 45 06 20
300 GEOGRAPHY AND GEOLOGY OF ALASKA.

BROOKS, ALFRED H. Alaska: The Eng. and Min. Jour., vol. 79, pp. 16 and 17. 1905. (Map.)

 The outlook for coal mining in Alaska: Trans. Am. Inst. Min. Eng. Washington meeting, May, 

1905, pp. 1-17. (Map.)

 The geography of Alaska, with an outline of the geomorphology: Eighth International Congress of Geography, 1905, pp '204-230. (Map.)

 An exploration in the Mount McKiuley region, Alaska: Prof. Paper U. B. Geol. Survey, in 

preparation. (Maps.)

 The Alaska Range. A new field for the mountaineer: Bull. Am. Geog. Soc., vol. 37, 1905, 

pp. 468-479. (Map.)

 Krrors about Alaska: The Outlook, July, 19C5, pp. 249-250.

 and others. Report on progress of investigations of mineral resources of Alaska in 1904: Bull. 

U. S. Geol. Survey No. 259, 1905, pp.-1-196. "(Maps.) 

See also Schrader, Hayes, and Peters.

 Geologic survey of Alaska: Pop. Sci. Monthly, Jan., 1906, pp. 42-54. (Maps.)

 and others. Report on progress of investigations of mineral resources of Alaska in 1905: Bull. 

U. S. Geol. Survey No. 284. (In preparation.) (Maps.)

RICHARDSON, G. B., and COLLIER, A. J. A reconnaissance of the Cape Nome and adjacent

gold fields of Seward Peninsula, Alaska, in 1900. In a special publication of the United States 

Geological Survey, entitled " Reconnaissances in the Cape Nome and Norton Bay Regions, 

Alaska, in 1900." Washington, Government Printing'Office, 1901. pp. 1-180. (Maps.)

BRUCE, MINER W. Alaska: Its History, Resources, Gold Fields, and Scenery. Seattle, 1895. Pp.128. 

(Maps.)

CANTWELL, Lieut. J. C. Exploration of the Kowak River, Alaska: U. S. R. M., cruise of the Corurin in 

the Arctic, 1885, pp. 21-52. (Maps.)

 Report of the Operations of the United States Revenue Steamer Nunivak on the Yukon River 

Station, Alaska, 1899-1901. Washington, Government Printing Office, 1902. pp. 1-325.

CASTNER, Lieut. J. C. Reports of explorations in the Territory of Alaska, 1898. Adjutant-General's 

Office, War Department, No. 25, 1899. (Maps.)

COLLIER, ARTHUR J. A reconnaissance of the northwestern portion of Seward peninsular, Alaska: 

Prof. Paper U. S. Geol. Survey No. 2, 1903, pp. 1-70. (Maps.)

 Placer mines of Seward Peninsula, Alaska: U. S. Geol. Survey, in preparation. (Maps.)

 The coal resources of the Yukon, Alaska: Bull. U. S. Geol. Survey No. 218, 1903, pp. 1-71. 

(Maps.)

 Coal resources of the Yukon basin, Alaska: Bull. U. S. Geol. Survey No. 213, 1903, pp. 276-283.

 Tin deposits of the York region, Alaska: Bull. U. S. Geol. Survey No. 225, 1904. pp. 154-167. 

(Maps.)

 Tin deposits of the York region, Alaska: Bull. U. S. Geol. Survey No. 229, 1904, pp. 1-61. 

(Maps.)

 Geology and coal resources of the Cape Lisburne region, Alaska: Bull. U. S. Geol. Survey No. 

278, 1906. (Maps.)

 , HESS, FRANK L., and BROOKS, ALFRED H. Gold placers of a part of the Seward Peninsula, 

Alaska: Bull. U. S. Geol. Survey No. . (In preparation.) (Maps.) 

Bee also Brooks.

COLLINSON, Capt. C. B. Proceedings of Captain Collinson in H. M. S. Enterprise, Bering Strait Division of Arctic Search, 1851-1854. (Blue Book.) (Maps.)

COOK, FREDERICK A. America's unconquered mountain: Harper's Monthly Magazine, vol. 108, 1904, 

pp. 230-239 and pp. 335-344.

 Round Mount McKinley: Am. Geog. Soc. Bul., vol. 36, 1904, pp. 257-264. (Map.)

 Results of a journey around Mount McKinley: Rept. Int. Geog. Gong., 1904, pp. 758-762.

COOK, Capt. JAMES. Voyage to the Pacific Ocean in the years 1776-1780. 3 vols. London, 1782, 1784, 

and 1785. (Maps.)

COXB, Rev. WILLIAM. Account of the Russian Discoveries between Asia and America, London, 1780, 

1787. Pp. 1-456. (Maps.)

DALL, WILLIAM H. Die Telegraphen-Expedition auf dem Jukon in Alaska. Mit Karte. N19. Peterman' s Geographlsehe Mitteilungen, 1869, Heft X. Gotha, Justus Perthes. pp. 361-365. (Maps.)
PUBLICATIONS ON ALASKA AND ADJACENT REGIONS. 301

DALL, WILLIAM H. Note on the geology of Alaska: Am. Jour. Science and Arts, January, 1868.

 Alaska and its Resources. Boston, 1870, pp. 1-627. (Map.)

 Geology and topography of the St. Elias region: California Acad. Sci., vol. 5, 1873-1875, 

].. 401.

 Pacific Coast Pilot. Coast and Islands of Alaska. Appendix I. Meteorology and Bibliography. Washington, 1879. Pp. 1-375. (Maps.)

 Pacific Coast Pilot, Alaska, pt. 1. Coast from Dixon's Entrance to Yakutat Bay, with the 

Inland Passages: V. S. Coast and Geodetic Survey, Washington, 1883, pp. 1-333. (Maps.)

 Rnsso-American Telegraph. Project of 1864-1867: Nat. Geog. Mag., vol. 3, 1891, pp. 110-111.

 Alaska as it was and is, 1865-1895: Philos. Soc. Washington, 1895-1899, pp. 123-161.

 Report on the coal and lignite of Alaska: Seventeenth Ann. Kept. II. S. Geol. Survey, pt. 1 

1896, pp. 763-906. (Maps.)

 The future of the Yukon gold fields: Nat. Geog. Mag., vol. 9, 1898, pp. 117-120.

 A Yukon Pioneer. Mike Lebarge: Nat. (ieog. Mag., vol. 9, 1898, pp. 137-139.

 The discovery and exploration of Alaska: Harriman Alaska Expedition, vol. 2, 1902, 

pp. 185-204. New York. (Map.)

and HAKKIS, G. D. Summary of knowledge of Neocene geology of Alaska: Bull. U. S. Geol.

Survey No. 84, 1892, pp. 232-268. (Maps.) 

DAVIDSON, GEORGE. Coast Pilot of Alaska. First part from southern boundary to Cook Inlet. Pacific 

coast. U. S. Coast and Geodetic Survey, Washington, 1869, pp. 1-251. (Maps.)

 Pacific Coast Pilot, Alaska, pt. 1. Coast from Dixon Entrance to Yakutat Bay, with inland 

passages. U. S. Coast and Geodetic Survey, 1883, pp. 1-333. (Map.)

 A chapter in the physical geography of southeastern Alaska: Bull. Geog. Soc., Philadelphia, 

vol. 2, 1900, pp. 108-114. (Map.)

Glaciers of Alaska: Trans. and Proc. Geog. Soc. Pacific, vol. 3, 2d ser., June, 1904, pp. 1-98.

(Maps.)

DAWSON, GEORGE M. Note on some of the more recent changes in level of the coast of British Columbia 

and adjacent region: Canadian Nat., new series, vol. 8, 1878, pp. 241-248.

 Report on the Queen Charlotte Islands, 1878: Rept. Prog. Geol. Nat. Hist. Survey Canada, 

1878-79, pp. 101B-189B. (Maps.)

 Report on an exploration from Port Simpson on the Pacfic coast to Edmonston on the 

Saskatchewan, embracing a portion of the northern part of British Columbia and the Peace 

River country: Rept. Geol. Nat. Hist. Survey Canada, pp. 1B-142B. 1881. (Map.)

 Sketch of the geology of British Columbia: The Geological Magazine, new series, decade 2, 

vol. 8, 1881, pp. 156-162 and 214-227. (Maps.)

 Preliminary report on the geology of the Bow and Belly River region, Northwest Territory, 

with special reference to the coal deposits: Geol. Nat. Hist. Survey Canada, pp. 1B-23B. 1883. 

(Map.)

 Report on a geological examination of the northern part of Vancouver Island and adjacent 

coasts: Ann. Rept. Geol. Nat. Hist. Survey Canada, new series, vol 2, 1887, pp. 1-107. (Maps.)

 Report on an exploration in the Yukon district, Northwest Territory, and adjacent northern 

portion of British Columbia, 1887: Ann. Rept. Geol. Nat. Hist. Survey Canada, new series, 

vol. 3, pt. 1, 1889, pp. 5B-277B. (Maps.)

 Report on a portion of the West Kootenay district, British Columbia, 1889: Ann. Rept. Geol. 

Nat. Hist. Survey Canada, new series, vol. 4, 1890, pp. 5B-65B. (Maps.)

 On the later physiographical geology of the Rocky Mountain region in Canada, with special - 

reference to changes, elevation, and history of the Glacial period, Canada: Trans. Royal Soc. 

Canada, vol. 8, sec. 4, pp. 3-74, 1890. (Maps.)

 Report on the area of the Kamaloops map sheet, British Columbia: Ann. Rep. Geol. Survey 

Canada, new series, vol. 7, 1894, p. 10B. (Maps.)

Geological record in Rocky Mountain region in Canada: Bull. Geol. Soc. America, vol. 12,

1901, pp. 57-92.

DENNIS, ALFBED PIERCE. Life on the Yukon Trail: Nat. Geog. Mag., vol. 10, 1899, pp. 458-466. 

DIXON, GEORGE, and PORTLOCK, NATHANIEL. Voyage Around the World, but more particularly to the

Northwest Coast of America. London, 1789. 360pp. (Maps.)
802 GEOGRAPHY AND GEOLOGY OF ALASKA.

DUNHAM, SAMUEL C. Yukon and Nome gold regions: Bull. Dept. Labor. No. 29, July, 1900, 

pp. 832-872.

 The Goldsmith of Nome. Washington, D. C., 1901. pp. 1-80.

ELURIDHE, GEOKGE H. The extreme southeastern coast. Maps and Descriptions of Routes of Exploration in Alaska, in 1898, with General Information Concerning the Territory. U. S. Geol. Survey, 

1899. pp. 101-103. (Maps.)

 The coast from Lynn Canal to Prince William Sound. Maps and Descriptions of Routes of 

Exploration in Alaska in 1898, with General Information Concerning; the Territory. U. S. Geol. 

Survey, 1899, pp. 103-104. (Maps.)

 The Sushitna drainage area. Maps and Descriptions of Routes of Exploration in Alaska 

in 1898, with General Information Concerning the Territory. U. S. Geol. Survey, 1899, pp. 111-113. 

(Maps.)

 Reconnaissance in the Sushitna basin and adjacent territory in Alaska, in 1898: Twentieth 

Ann. Rept. II. S. Geol. Survey, pt. 7, 1900, pp. 1-29. (Map.)

and MULDROW, BOBEBT. Report of the Sushitna expedition. Maps and Description of Routes

of Exploration in Alaska in 1898, with General Information Concerning the Territory. U. S. Geol.

Survey, 1899, pp. 15-28. (Maps.) 

EMERSON, B. K., and GII.BEKT, G. K., and PALACHE, CHARLES. General Geology of Alaska: Harriman

Alaska Expedition, vol. 4. New York, 1904. pp. 11-64. (Maps.) 

EMMOXS, S. F. Map of Alaska, showing known gold-bearing rocks, with descriptive text containing

sketches of the geography, geology, and gold deposits, and routes to the gold fields: U. S. Geol.

Survey, 1898, pp. 1-44. (Map.)

 Alaska and its mineral resources: Nat. Geog. Mag., vol. 9, 1898, pp. 139-172. (Map.) 

EVANS, WALTER H., and KILUAM, BEKTOX, and JACKSON, SIIELDON. A report to Congress on agriculture in Alaska: U. S. Dept. Agriculture, Office of Experiment Stations, Bull. 48, 1898, pp. 1-30.

 Some of the conditions and possibilities of agriculture in Alaska: Nat. Geog. Mag., vol. 9, 1898,

pp. 178-187. 

FERNOW, B. E. Forests of Alaska: Harriman Alaska Expedition, vol. 2. New York, 1902,

pp. 235-266. (Map.) 

FILIPPO, FILIPPI J)E. The Ascent of Mount St. Elias (Alaska). By H. R. H. Prince Luigi Amedeo.

Di Savoia. Duke of the Abruzzi. Translated by Signora Linda Villari. London, 1900.

pp. 1-240. (Maps.)

FOSTER, JOHN W. The Alaska boundary: Nat. Geog. Mag., vol. 10,1899, pp. 425-456. (Maps.) 

FRANKLIN, Sir JOHN. Narrative of a Second Expedition to the Shores of the Polar Sea from 1825 to

1827. London, 1828. 4to. pp. 1-322. (Maps.) 

GAKNETT, HENRY. Harriman Alaska Expedition: Nat. Geog. Mag., vol. 10, 1899, pp. 507-612. (Map.)

 Altitudes in Alaska: Bull. II. S. Geol. Purvey No. 169, 1900, pp. 1-13.

 General geography, Alaska: Harriman Alaska Expedition, vol. 2. New York, 1902.

pp. 257-277. (Maps.) 

GARSIDE, G. W. The mineral resources of southeast Alaska: Trails. Am. Inst. Mm. Eng., vol. 21,

1893, pp. 815-823. (Map.) 

GEORGESON, C. C., and EVANS, WALTER H. Second report to Congress on agriculture in Alaska: U. S.

Dept. Agriculture, Office of Experiment Stations, Bull. 62, Washington, 1899, pp. 1-51.

 Report on agricultural investigations in Alaska in 1899: II. S. Dept. Agriculture, Office of 

Experiment Stations, Bull. 82, pp. 1-55.

 Fourth Report on the Agricultural Investigations in Alaska, 1900.

 Annual report of the Alaska agricultural experiment station for 1901: U. S. Dept. Agriculture, Office of Experiment Stations, Bull. No. 5)4, 1901, pp. 1-83.

Report of the Alaska Agricultural Experiment Station for 1902: Ann. Rept. of the Office of

Experiment Stations, IT. S. Dept. Agriculture, for the year ending June 30, 1902, pp. 239-359. 

GiLBEBT, G. K. Glacier3:HarrimanAlaskaExpedition, vol. 3. New York, 1904. pp. 1-231. (Maps.) 

E. J. Pioneer pack horses in Alaska: Centnry Mag., Sept., 1892, pp. 671-681, and Oct., 1892, 

pp. 869-881. (Map.)

MABTTN W. Ice cliffs on White River, Yukon Territory: Nat. Geog. Mag., vol. 2, 1900, 

pp. 113-117.
PUBLICATIONS ON ALASKA AND ADJACENT REGIONS. 303

GRINNELL, Joseph. Gold Hunting in Alaska. Chicago, 1901. pp. 1-96.

GWILLIM, J. C. Report on the Atlin mining district, British Columbia: Ann. Kept. Geol. Nat. Hist. 

Survey Canada, new series, vol. 12, 1899, pp. 5B-48B. (Map.)

 Glaciation in the Atlin district: Jour. Geol., vol. 10, 1902, p. 182.

HAYES, C. W. An expedition through the Yukon district: Nat. Geog. Mag., vol. -1, 1892, pp. 117-162. 

(Maps.)

 Yukon district and basin: Jour. School Geog., vol. 1, 1897, pp. 238-241, 269-274.

 and BROOKS, ALFRED H. Ice cliffs on White River: Nat. Geog. Mag., vol. 11,1900, pp. 190-201.

HEALEY, Capt. M. A. Cruise of the Revenue Steamer Cm-win in the Arctic Ocean in 1885. Washington, 1887. pp. 1-102. (Map.)

HERRON, First Lient. JOSEPH S. Explorations in Alaska in 1899. Adjutant-General's Office, War 

Department, No. 31, pp. 1-77. (Maps.)

HOWAUD, Lieut. W. L. Expedition to Point Barrow, Naval Exploration in Alaska, 1900. (Map.)

HUNT, WILLIAM 0. Twelfth Census United States. Population. vol. 1. Washington, 1901. 

pp. 1006.

JACKSON, SHELUON. Report, on Education in Alaska. Twenty-three annual reports from the years 

1880 to 1902, contained in Annual Reports of Commissioner of Education, Dept. of Interior. 

(Maps.)

 Report on introduction of domestic reindeer into Alaska. Thirteen annual reports from years 

1890 to 1902. Bureau of Education, Dept. of the Interior. (Maps.)

JAHVIS, Lieut. I). H. Report of the Cruise of the Revenue Cutter TJwraud the Overland Relief Expedition. Washington, 1899. pp. 1-144.

 Coast Pilot Notes on the FOX Island Passes, Unalaska Bay, Bering Sea and Arctic Ocean, as 

far as Point Barrow: Bull. No. 40, II. S. Coast and Geodetic Survey, 2d edition, 1900, pp. 1-60.

JOHNSON, ANDREW. Message from the President of the United States in answer to a resolution from 

the House of the 19th of December last, calling for information relative to Russian America, April 

21, 1868: 40th Congress, 2d session, Executive Document 177, pt. 2, pp. 1-361.

 Message from the President of the United States in relation to the transfer of territory from 

Russia to the United States: 40th Congress, 2d session, House of Representatives, Executive Document No. 125, June, 1868, pp. 1-65. (Map.)

KEELE, JOSEPH. Duncan Creek mining district (Stewart River, Yukon Territory): Summary Report, 

Geol. Survey Dept. of Canada for the calendar year 1904. Ottawa, 1905. pp. 18-42. (Map.)

KENNICOTT, ROBEKT. Russian America: The Atlantic Monthly, vol. 19, 1867, pp. 731-750.

KNOWLTON, F. H. Report on fossil plants from Pinnacle Pass, near Mount St. Elias, Alaska: Nat. 

Geog. Mag., vol. 3, 1891, pp. 199-200.

 Review of the fossil flora of Alaska, with descriptions of new species: Proc. U. S. Nat. Museum, 

vol. 17, 1894, pp. 20-240.

 Report on fossil plants collected in Alaska in 1895, as well as an enumeration of those previously known from the same region, with a table showing their relative distribution: Seventeenth Ann. Kept. U. S. Geol. Survey, 1896. pt. 1, pp. 876-897.

Report on a collection of fossil plants from the Yukon River, Alaska: Eighteenth Ann. Rept.

U. S. Geol. Survey, 1898. pt. 3, pp. 194-196. 

KOTZEBUE, Lieut. OTTO VON. Voyage of Discovery into the South Sea and Bering Straits, for the Purpose of Exploring a Northeast Passage, in 1815-1818. Translated by H. E. Lloyd. London, 1821.

3 vols. (Maps.) 

LANSING, ROBERT. The question settled by the award of the Alaskan boundary tribunal: Bull.

American Geog. Soc., vol. 36, 1904, pp. 65-80. (Map.) 

LtjTKE, Capt. FREDERIC. Voyage autour du Monde sur la Corvette le Reniavine,, dans les Annees 1826

to 1829. Paris, 1835-1836, pp. 1-58. (Maps.) 

MARTIN, G. C. Geology of the Controller Bay coal field, Alaska: Bull. IT. S. Geol. Survey No. .

(In preparation.) (Maps.) 

 Preliminary report on the Matanuska coal field, Alaska: Bull. U. S. Geol. Survey No. .

(In preparaiion.) (Maps.)
304 GEOGRAPHY AND GEOLOGY OF ALASKA.

McCoNNELL, R. G. Report on the geological structure of a portion of the Rocky Mountains, accompanied by a section measured near the fifty-first parallel: Ann. Kept. Geol. Nat. Hist. Survey 

Canada, new series, vol. 2, 1887, pp. 7D-40D. (Maps.)

 Report on an exploration in the Yukon and Mackenzie basins, N. W. T.: Ann. Rept. Geol. 

Nat. Hist. Survey Canada, new series, vol. 4, 1890, pp. 5D-144D. (Maps.)

Report on a portion of the district of Athabasca, comprising the country between Peace River

and Athabasca River north of the Lesser Slave Lake: Ann. Rept. Geol. Survey Canada, new 

series, vol. 5, 1893, pp. 1D-62D. (Maps.)

 Report on an exploration of the Finley and Ornenica rivers, British Columbia: Ann. Rept. 

Geol. Survey Canada, new series, vol. 7, 1896, pp. 1C-40C. (Maps.)

 The Yukon district: Summary Rept. Geol. Survey Canada for 1900. pp. 39 and 40.

 The old valley gravels of the Klondike: Jour. Canadian Min. Inst, vol. 3, 1900, pp. 124-172.

 Preliminary report on the Klondike gold fields, Yukon district: Geol. Survey Canada, Ottawa, 

Canada, 1900. pp. 1-44. (Map.)

 Salmon River gold fields: Summary Rept. Geol. Survey Canada for 1901.

 Notes on the so-called basal granite of the Yukon Valley: Am. Geol., vol. 30, 1902, pp. 55-62.

 Kluane mining district (southwestern portion of Yukon district): Summary report, Geol. 

Survey Dept. of Canada for the calendar year 1904, pp. 1-18. (Map.) 

 Report on the Klondike gold fields: Part B, Ann. Rept. Geol. Survey of Canada, vol. 14, 1905,

pp. 1B-71B. (Maps.) 

MCGBATH, J. E. The boundary south of Fort Yukon: Nat. Geog. Mag., vol. 4, 1892-93, pp. 181-188.

See also U. S. C. and G. S. Ann. Rept. for 1891, pt. 1. p. 86. 

McKEE, LAINIEB. The Land of Nome. New York, 1902. pp. 1-260. 

McLENEQAN, S. B. Exploration of the Noatak River, Alaska. Report of the cruise of the Revenue

Cutter steamer Corwin, 1885. Washington, 1887. (Map.) 

MACKENZIE, ALEXANDER. Voyages from Montreal over the Continent of North America to the

Frozen and Pacific Oceans, in the Years 1780-1793. London, 1801. 4to. pp. 1-412. (Maps.) 

MARTIN, G. C. Petroleum fields of the Pacific coast of Alaska and the Bering River coal deposits:

Bull. TJ. S. Geol. Survey, No. 250, 1905. pp. 1-64. (Maps.)

MENDENHALL, T. C. The Alaskan boundary survey: Nat. Geog. Mag., vol 4, 1892-93, pp. 177-180. 

MENDENHALL, W. C. The Kenai Peninsula. Maps and Descriptions of Routes of Exploration in

Alaska in 1898, with General Information Concerning the Territory. U. S. Geol. Survey, 1899.

pp. 109-111. (Maps.)

 The Kodiak Islands. Maps and Descriptions of Routes of Exploration in Alaska in 1898, with 

General Information Concerning the Territory. U. S. Geol. Survey, 1899. pp. 113-115. (Maps.)

 The Alaska Peninsula and the Aleutian Islands. Maps and Descriptions of Routes of 

Exploration in Alaska in 1898, with General Information Concerning the Territory. U. S. Geol. 

Survey, 1899. pp. 115-118. (Maps.)

 Report on the region between Resurrection Bay and the Tanana River. Maps and Descriptions 

of Routes of Exploration in Alaska in 1898, with General Information Concerning the Territory. 

U. 8. Geol. Survey, 1899. pp. 40-51. (Maps.)

 Reconnaissance from Resurrection Bay to the Tanana River, Alaska, in 1898: Twentieth 

Ann. Rept. U. S. Geol. Survey, pt. 7, 1900, pp. 265-340. (Map.)

 Reconnaissance in the Norton Bay Region, Alaska, in 1900. In a special publication of the 

United States Geological Survey, entitled "Reconnaissances in the Cape Nome and Norton Bay 

Regions, Alaska, in 1900." Washington, Government Printing Office, 1901. pp. 181-218. (Maps.)

 A Reconnaissance from Fort Hainlin to Kotzebue Sound, Alaska: Prof. Paper U. S. Geol. 

Survey No. 10, 1902. pp. 1-68. (Maps.)

 The Chistochina gold field, Alaska: Bull. U. S. Geol. Survey No. 213, 1903. pp. 71-75.

 The Wrangell Mountains, Alaska: Nat. Geog. Mag., vol. 14, 1903, pp. 395-407.

 Geology of the central Copper River basin: Prof. Paper TJ. S. Geol. Survey No. 41, 1904. 

(Maps.)

 and SCHRADEH, F. C. Copper deposits of the Mount Wrangell region, Alaska: Bull. II. S.

Geol. Survey No. 213, 1903. pp. 141-148.
PUBLICATIONS ON ALASKA AND ADJACENT REGIONS. 305

MENDF.NHALL, W. C., and SCHBADER, F. C. The Mineral Kesources of the Mount Wrangell district, 

Alaska: Prof. Paper U. S. Geol. Survey No. 15, 1903. pp. 1-71. (Maps.)

MOFFIT, F. II. The Kotzebue placer gold field of Seward Peninsula, Alaska: Bull. TJ. S. Geol. Survey 

No. 225, 1904. pp. 74-80.

 The Fairhaven gold placer district of the Seward Peninsula: Bull. TJ. S. Geol. Survey No. 247, 

1904, pp. 1-85, (Maps.)

 and STONE, R. W., Mineral resources of the Kenai Peninsula, Alaska: Bull. TJ. S. Geol.

Survey No. 277. (In preparation.) (Maps.)

Mum, JOHN. The Discovery of Glacier Bay: Century Mag., June, 1895. pp. 234-247. (Map.) 

NELSON, E. W. Notes on the Wild Fowl, Game, and Animals of Alaska: Nat. Geog. Mag., vol. 9,1898,

pp. 121-132. 

OGILVIE, WILLIAM. Exploratory survey of part of the Lewes, Tatonduc, Bell, Trout, Peel, and

Mackenzie rivers, 1887-88. Ottawa, 1890, Dept. of the Int. (Maps.)

 The Klondike Official Guide. Buffalo, 1898. 7-144 pp., 21 pi., 5 pis. (Map.)

Toronto, 1898. pp. 1-144. (Maps.) 

OSGOOD, WILFEED H. Natural History of the Queen Charlotte Islands, British Columbia. Natural

History of the Cook Inlet Region. TJ. 8. Dept. Agriculture, Division of Biological Survey, North

American Fauna, No. 21, 1901. p. 87. (Map.)

 and BISHOP, Louis B. Results of a Biological Reconnaissance of the Yukon River Region. 

II. S. Dept. Agriculture, Division of Biological Survey, North American Fauna, No. 19, 1902. 

pp. 100. (Map.)

Biological reconnaissance of the base of the Alaska Peninsula, U. S. Dept. Agriculture,

Division of Biological Survey, North American Fauna, No. 24, 1904, pp. 81-86. (Maps.) 

PAIGE, SIDNEY. A growing camp in the Tanana Gold Fields, Alaska: Nat. Geog. Mag., vol. 16, 1905,

pp. 104-111. 

PALACHE, Dr. CHAELES. Geology about Chichagof Cove, Stepovak Bay: Harriman Alaska Expedition,

vol. 4, New York, 1902. pp. 69-88. (Map.)

PEEKINS, GEOEGE C. The civil government of Alaska: Nat. Geog. Mag., vol. 9, 1898, pp. 172-178. 

PETERS, W. 3., and BEOOKS, ALFEED H. Report of the White River-Tanana Expedition. Maps and

Descriptions of Routes of Exploration in Alaska in 1898, with General Information Concerning

the Territory. II. S. Geol. Survey, 1899. pp. 64-76. (Maps.) 

PETEOFF, IVAN. Report on Population, Industries, and Resources of Alaska. Tenth Census United

States, vol. 8, pp. 1-189. (Maps.) 

POOLE, FRANCIS. Queen Charlotte Islands. A Narrative of Discovery and Adventure in the North

Pacific, 1872. pp. 1-377. 

POETEE, ROBEET P. Population and Resources of Alaska at the Eleventh Census, 1890. Census Office.

Department of the Interior, 1893. pp. 1-282. (Maps.)

PEESTON, E. D. The Copper River delta: Nat. Geog. Mag., vol. 11, 1901, pp. 29-31. 

PEINDLE, L. M. Gold placers of the Fairbanks district, Alaska: Bull. U. S. Geol. Survey No. 225,

1904. pp. 64-73. (Map.) 

 The gold placers of the Forty mile, Birch Creek, and Fairbanks gold districts: Bull. TJ. S.

Geol. Survey No. 251, 1904. pp. 1-84. (Maps.) 

 and HESS, F. L. The Rampart gold-placer region, Alaska: Bull. U. S. Geol. Survey No. 280.

(In preparation.) 

RAY, Lieut. P. H. Report of the International Polar Expedition to Point Barrow, Alaska, 1881-1884,

U. S. War Department. Executive Document No. 44, House of Representatives, 48th Congress.

2d session. (Maps.) 

RAYMOND, Capt. CHAELES W. Report of a Reconnaissance of the Yukon River, Alaska Territory, 1869,

Corps of Engineers, TJ. S. Army. Senate Executive Document No. 12, 42d Congress, 1st session.

113pp. (Map.) 

REID, H. F. Glacier Bay and its glaciers: Sixteenth Ann. Rept. U. S. Geol. Survey, 1896. pt. 1, pp.

415-461. (Maps.) 

ROHN, OSCAE. Reconnaissance of the Chitina River and the Skolai Mountains, Alaska: Twenty-first

Ann. Rept. TJ. S. Geol. Survey, 1900. pt. 2, pp. 393-440. (Map.) 

Rbss, Capt. JOHN. Narrative of a Second Voyage in Search of a Northwest Passage. London, 1835.

4to, three volumes.
306 GEOGRAPHY AND GEOLOGY OF ALASKA.

ETISSELL, FRANK. Explorations in the Far North. Published by the University of Iowa, 1898.

pp. 1-290. (Map.) 

RUSSELL, I. C. Ice cliffs on Kowak Eiver observed by Lieutenant Oantwell: Am. Geol., vol. 6, 1890.

pp. 49-50.

 Notes on surface geology of Alaska: Bull. Geol. Soc. America, vol. 1, 1890. pp. 72, 99, 154, 155.

 Expedition to Mount St. Elias, Alaska: Nat. Geog. Mag., vol. 3, 1890. pp. 53-194. (Maps.)

 Account of an expedition to the Yukon Valley in 1889: Eleventh Ann. Eept. U, S. Geol. 

Survey, 1891. pt. 1, pp. 57-58.

 Account of an expedition to the vicinity of Mount St. Elias in 1890: Twelfth Ann. Eept. U. S. 

Geol. Survey, 1891. pt. 1, pp. 59-61. (Maps.)

 Explorations in Alaska: Am. Geol., vol. 7, 1891. pp. 33,38.

 Second expedition to Mount St. Elias, 1891: Thirteenth Ann. Kept. TJ. S. Geol. Survey, 1893. 

pt. 2, pp. 1-91. (Maps.)

 Mount St. Elias and its glaciers: Am. Jour. Sci., 3d ser., vol. 43, 1892. pp. 169-182.

 Alaska: its Physical Geography: Scottish Geog. Mag., vol. 10, 1894. pp. 393-413. (Maps.) 

RUSSIAN TREATS, ALASKA. Fortieth Gong., 2d sess., House of Representatives, Ex. Doc. No. 125,

1-361. Fortieth Cong., 2d sess., House of Representatives, Ex. Doc. No. 177, 1-65. 

SCHRADEH, F. C. Eeport on Prince William Sound and the Copper Eiver Region. Maps and Descriptions of Koutes of Exploration in Alaska in 1898, with General Information Concerning the 

Territory. U. S. Geol. Survey, 1899, pp. 51-64 and 105-109. (Maps.)

 Reconnaissance of a part of Prince William Sound and the Copper Eiver district, Alaska, in 

1898: Twentieth Ann. Rept. U. S. Geol. Survey, 1899. Pt. 7, pp. 341-423. (Maps.)

 Preliminary report on a reconnaissance along Chandlarand Koyukuk rivers, Alaska, in 1899: 

Twenty-first Ann. Rept. U. S. Geol. Survey, pt. 2, 1900, pp. 441-486. (Maps.)

 and BEOOKS ALFRED II. Preliminary report on the Cape Nome gold region, Alaska: U. S. 

Geol. Survey, 1900. pp. 1-56. (Maps.)

 and SPENCER, ARTHUR C. The Geology and Mineral Resources of a Portion of the Copper 

River district, Alaska. A special publication of the United States Geological Survey, Washington, Government Printing Office, 1901. pp. 1-94. (Maps.)

 Eecent work of the United States Geological Survey in Alaska: Bull. American Geog. Soc., 

vol. 34, 1902, pp. 1-145.

 A reconnaissance in northern Alaska across the Rooky Mountains, along the Koyukuk, 

John, Anaktuvuk, and Colville rivers, and the Arctic coast to Cape Lisburne, in 1901: Prof. 

Paper U. S. Geol. Survey No. 20, 1904. pp. 1-134. (Maps.)

Geology of the upper Copper and Tanana rivers: U. S. Geol. Survey, in preparation. (Maps.) 

Geological section of the Rocky Mountains in northern Alaska: Bull. Geol. Soc. America.

vol. 13, 1902, pp. 232-252. (Map.)

See also Mendenhall.

SCHWATKA, FREDERICK. Military Reconnaissance in Alaska, with maps, in 1883. Executive Document 

No. 2, 48th Cong., pp. 282-362, 20 pi. (Maps.)

 Along Alaska's Great Eiver. New York, 1885. pp. 360. (Map.)

 Expedition of the New York Times: The Century Magazine, April, 1891, with sketch map. 

SCIIJMORE, ELIZA RniAMAH. Handbook to Alaska. New York, 1899. Alaska, the Sitkan Archipelago. 

Boston, 1885. (Maps.)

 The discovery of Glacier Bay: Nat. Geog. Mag., vol. 7, 1896, p. 143.

 Northwest passes to the Yukon: Nat. Geog. Mag., vol. 9, 1898, pp. 106-116.

SENATE, U. S. Hearings before subcommittee of Committee on Territories, appointed to investigate

conditions in Alaska. Fifty-eighth Congress, 2d session, Senate Report No. 282, Nos. 1 and 2.

(Map.) 

SIMPSON, THOMAS. Narrative of the Discoveries on the North Coast of America, effected by the officers

of the Hudson's Bay Company, during the years 1836-1839. London, 1843. pp. 419. (Maps.) 

SPENCER, ARTHCR C. The Pacific Mountain System in British Columbia and Alaska: Bull. Geol. Soc.

America, vol. 14, pp. 117-132. (Maps.)

 The Juneau gold belt, Alaska: Bull. U. S. Geol. Survey No. 225, 1904. pp. 28-42.
PUBLICATIONS ON ALASKA AND ADJACENT REGIONS. 307

SPENCER, AETHUR C. The Geology of the Juneau gold belt, Alaska: U. S. Geol. Survey, in preparation.

(Maps.)

See also Schrader. 

STANTON, T. W., and MARTIN, G. C. Mesozoic section on Cook Inlet and Alaska Peninsula: Bull.

Geol. Soc. America, vol. 16, pp. 391-410. (Maps.) 

SPURR, JOSIAH EDWARD. Geology of the Yukon gold district, Alaska, with an introductory chapter

on the history and conditions of the district to 1897 by Harold B. Goodrich: Eighteenth Ann.

Kept. U. S. Geol. Survey, 1898, pt. 3, pp. 87-392. (Maps.)

 Lakes Iliamna and Clark. Maps and Descriptions of Routes of Exploration in Alaska in 

1898, with General Information Concerning the Territory: IT. S. Geol. Survey, 1899. p. 118. 

(Maps.)

 The Kuskokwim drainage area. Maps and .Descriptions of Routes of Exploration in Alaska 

in 1898, with General Information Concerning the Territory: U. S. Geol. Survey, 1899. pp. 

122-123. (Maps.)

 The Noatak River. Maps and Descriptions of Routes of Exploration in Alaska in 1898, with 

General Information Concerning the Territory. U. S. Geol. Survey, 1899. p. 129. (Maps.)

 From the Yukon mouth to Point Barrow. Maps and Descriptions of Routes of Exploration 

in Alaska in 1898, with General Information Concerning the Territory. U. S. Geol. Survey, 1899. 

pp. 124-126. (Maps.)

 The Kowak River. Maps and Descriptions of Routes of Exploration in Alaska, in 1888, with 

General Information Concerning the Territory. U. S. Geol. Survey, 1899. pp. 127-129. (Maps.)

 and POST, W. S. Report of the Kuskokwim Expedition. Maps and Descriptions of Routes of 

Exploration in Alaska in 1898, with General Information Concerning the Territory. U. S. Geol. 

Survey, 1899. pp. 28-40. (Maps.)

 The coast from Bristol Bay to the Yukon. Maps and Descriptions of Routes of Exploration 

in Alaska in 1898, with General Information Concerning the Territory. U. S. Geol. Survey, 1899. 

pp. 120-121. (Maps.)

 The Nushagak River. Maps and Descriptions of Routes of Exploration in Alaska in 1898, with 

General Information Concerning the Territory. U. K. Geol. Survey, 1899. p. 119. (Maps.)

 Through the Yukon Gold Diggings. Boston, 1900. pp. 1-276.

Reconnaissance in southwestern Alaska in 1898: Twentieth Ann. Rept. U. S. Geol. Survey,

pt. 7, 1900, pp. 31-264. (Maps.) 

STELLER, GEORGE WILHELM. Beschreibung der See-reise von Kamschatka nach Amerika. Frankfurt,

1774.

STEVENS, JOHN J. Some notes on southeastern Alaska and its People: Scottish Geog. Mag., February, 1893, vol. 9. pp. 66-83. (Map.) 

STONE, R. W. Coal Fields Kachemak Bay and Vicinity: Bull. U. S. Geol. Survey. In preparation.

(Maps.)

STONEY, GEORGE M. Naval Exploration in Alaska. [J. S. Naval Institute, 1900. pp. 1-105. (Map.) 

SWINEFOHD, A. P. Alaska, its History, Climate, and Natural Resources. Chicago, 1898. pp. 1-256.

(Maps.) 

TEBENKOFF, Capt. MICHAEL. Hydrographic Atlas and Observations. With 48 charts. St. Petersburg,

1848 and 1852. (Maps.) 

TITTMANN, 0. H. United States Coast Pilot, Pacific coast, Alaska, Part I, Dixon Entrance to Yakutat

Bay, with inland passage from Juan de Fuca Strait to Dixon Entrance. 4th edition, 1901, pp.

1-246. (Maps.) 

TURNER, J. H. The Alaskan Boundary Survey: Nat. Geog. Mag., vol. 4, 1892. Also U. S. Coast and

Geodetic Survey, Ann. Rept., 1891, pt. 1. 

TYKRELL, J. B. Yukon district: Ann. Rept. Geol. Survey Canada, new series., vol. 11, 1898, pp.

36A-55A. 

 Glacial phenomena in the Canadian Yukon district: Bull. Geol. Soc. America, vol. 10, 1899,

pp. 193-198. (Map.)

Gold mining in the Klondike district, Alaska: Abstract, Am. Geol., vol. 23, 1899, p. 102.

 The geology of the Klondike region: Abstract, Scientific Am. Supplement, vol. 49, 1900, 

p. 20101.

 A peculiar artesian well in the Klondike, Eng. and Min. Jour., Jan. 31, 1903, vol. 75, p. 188.
308 GEOGRAPHY AND GEOLOGY OF ALASKA.

ULKICH, E. O. Fossils and Age of the Yakutat formation: Harriman Alaska Expedition. New York,

1904. vol. 4, pp. 124-126. 

VANCOUVER, Capt. GEOBGE. Voyage of Discovery to the North Pacific Ocean, etc., in the years 1790.

1795. London, 1798. 3 v. (Maps.) 

WALCOTT, C. D., Director. [Account of an investigation of the gold and coal deposits of southern

Alaska]: Seventeenth Ann. Kept. U. S. Geol. Survey, pt. 1, 1896, pp. 56-59.

 [Account of a reconnaissance of the gold district of the Yukon region]: Eighteenth Ann. Kept. 

U. S. Geol. Survey, pt. 1, 1897, pp. 52-54.

 [Account of operations in Alaska in 1898]: Nineteenth Ann. Kept. U. S. Geol. Survey, 1898. 

pt. 1, pp. 20, 53, 116, 117.

 [Account of operations in Alaska in 1899]: Twentieth Ann. Kept. U. S. Geol. Survey, 1899. 

pt. 1, pp. 12, 52, 53, 97, 126-134.

 [Account of operations in Alaska in 1900]: Twenty-first Ann. Kept. U. S. Geol. Survey, 1900. 

pt. 1, pp. 17-18, 86, 145-149.

 [Account of operations in Alaska in 1901]: Twenty-second Ann. Kept. U. S. Geol. Survey, 1901. 

pt. 1, pp. 35, 95-99, 144, 166-170.

 [Account of operations in Alaska in 1902]: Twenty-third Ann. Kept. U. S. Geol. Survey, 1902. 

pt, 1, pp. 20, 21, 57, 71-82, 161. (Maps.)

[Account of operations in Alaska in 1903]: Twenty-fourth Ann. Kept. U. S. Geol. Survey, 1903.

pp. 78-107, 167, 256. (Maps.) 

WAK DEPARTMENT. Explorations in Alaska. Washington, 1900. 856pp. (Maps.) 

WHITE, JAMES. Altitudes in the Dominion of Canada, with a relief map of North America; Geol.

Survey Canada, 745. Ottawa, 1901. Pp. 262, 1 map. (Map.)

 Dictionary of altitudes in Dominion of Canada, with a relief map of Canada. Dept. of the Int.,

Ottawa, 1903. 1-143 pp. (Map.) 

WHYMPER, FREDERICK. Travel and Adventure in the Territory of Alaska, and in various other parts

of the North Pacific. London, 1868. 5-353 pp., 17 pi. (Maps.) 

.WILLIAMS, WILLIAM. Climbing Mount St. Elias: Scribner's Mag., April, vol. 5, 1889, pp. 387-403.

(Maps.)

WILSON, BECKLES. The Great Fur Company, 1667-1871. London, 1900. 2 vols. (Maps.) 

WOOD, C. E. S. Among the Thlinkits in Alaska: Century Mag., vol. 24, 1882, pp. 323-339. 

WOODMAN, ABRIE JOHNSON. Picturesque Alaska. The journal of a tour among the mountains, seas,

and islands of the Northwest from San Francisco to Sitka. 1889. pp. 1-225. (Maps.) 

WEIGHT, C. W. The Porcupine placer mining district, Alaska: Bull. U. S. Geol. Survey No. 225,

1904. pp. 60-63. (Map.)

 The Porcupine placer mining district, Alaska: Bull. U. S. Geol. Survey No. 236, 1904. 

(Maps.)

A reconnaiaaance of Admiralty laland: Bull. tl. S. Geol. Survey. In preparation. (Maps.)

WRKSHT, F. E., and C. W. Mineral resources of the Wrangell and Ketchikan mining districts, Alaska:

Bull. U. S. Geol. Survey, No. . (In preparation.) (Maps.) 

WEIGHT, G. FEEDERIOK. The Ice Age of North America. New York, 1889. (Maps.) pp. 662,

incl., 38 pis., 1 pi., 3 maps. 

ZAGOSKIN, Lieut. L. Travels on Foot and Description of the Russian Possessions in America, from

1842-1844. St. Petersburg, 1847. (Russian.) (Maps.) Also in German in "Erman's Archiv

fur wissenschaftliche Kunde von Russland," vols. 6 and 7. (Maps.)
INDEX.

A-. Pago. 

Abandoned valleys. See Streams. 

Abbe, Cleveland, jr., section on climate by........... 133-200

Abercrombie, W. R., explorations by ....... 122,127-128,130

Abercrombie Glacier, location of.................... 56

Aborigines, character of................ 20,82,91,107,108,110 j

food of, sources of........................ 20,04,82,86,88 [

fur-trade interests of............................ 67-68

groups of...............-.-......---...-.-....-.. 88

intercourse among............................... 58,

60,61,62,64,74,91,95,97,102,120-121 

routes and trails followed by.................... 31,

35, 50-51, 56, 58, 61, 64, 71,74,76,82, i 86,88,91,97,100,101,102-103,121,125 i 

llussian conflicts and dealings with ..... 108,110,113,114

settlements of................................. 75,95,100 j war weapons of.................................. 108

waterways traversed by...... 64,71,82,86,91,100,102-103

See also^navies of native tribes. 

Adams Lake series, age and equivalents of........ 206 (table)

Admiralty Island, description of.................... 19

geology of....................................... 254-255

lignitic coal of................................... 239

section across.......................... 254 (PI. XXVII)

Alognak Island, location of......................... 22

Agiapuk River, location of.......................... 94

Agriculture, experiment-station service in.......... 134

possibilities of, in Tanana Valley................ 87

Ahklun Mountains, description of...----.......-.... 38-39

drainage of...................................... 64

glaciation in..................................... 245,247

Aishihik Lake, outlet of............................. 53

Alaska Peninsula, climatic province of, meteorologic

stations and climate in ........ 140-141,150-151

climatic record from stations in................. 138,

158-170,172,186-188,190,196,199 I 

coal-bearing beds on............................. 240 |

Cretaceous rocks 011............................. 237,252 j

drainage of...................................... 58,61 I

Eocene rocks on................................. 240,252 !

forest growth on................................. 145 '

glacial action on................................. 247 ;

intrusive rocks on............................... 210,250 i

location of....................................... 15 I

route across..................................... 128

Russian exploration of.......................... 108,109

stratigraphy of, table showing.................. 232

structure of...................................... 258

surveys of................................... 108,109,115

volcanic rocks in............................. 206,250,251

volcanism in................................. 250,251,290

Alaska Range, altitudes of.................... 34-30,272-273

base-level marked by summits of................ 287,288

drainage of...................... 34,57,58,59,61,82,86,87

glacial altitudes and snow line in................ 245

Page. 

Alaska Range,glaciation in........... 55,85,245,247,249,280

gravel plateau at northwest base of, plate showing..................................... 280

intrusives along............................. 204,232,250

sections across................. 254 (PI.XXVII),257,258

stratigraphy in.................................. 206,207

surveys through................................. 130

topographic features of.................... 33-36,272-273

trend of.......................................... 268

volcanic rocks in................................. 232

woodland in..................................... 36

Alaska-Siberia Railway, tunnel requirements of .... 27

Alatna River, exploration of................ 123,129,215-216

location of....................................... 89

routes to or along............................ 90,101,129

source and course of............................ 90,96,98

Alder River, location of............................. 94

Aleutian Islands, climate of..................... 141,145-146

climatic province of, extent of................... 141

climatic records from stations in................ 138,

151-152,158-170,173,189,195,200 

description of....-..--....--....---...---...----- 22

discovery of..................................... 107

explorations among................. 105,109,114,117,132

forest growth on.--........---....-.-..---....--. 145

fossils on........................................ 243

lignite-bearing beds on.......................... 241

longitudinal extent of........................... 140

topography of..-...................-.--..---.... 58

Aleutian Range, description of......--...---....---- 32-33

drainage of..................................... 58,59,61

glaciation in.....-....-.......-.....--....-.--... 247,249

origin of.........-........---...---....--...-- 33,258,275

structure of................................... 33,258,275

trend of.......................................... 268

volcanoes and volcanism in...................... 33,

250-251,258,275,290,291,295 

Aleuts, conflicts of Russian fur traders with........ 108

Alexander Archipelago, climate of................... 144

description of.................................... 19-20

Devonian rocks of............................... 218-219

glacial action in.---...--..-...----..---.----.---- 52,246

lignitic coal of................................... 238-239

Mcsozoic rocks of...........-.....-...----..-.... 226

metamorphic rocks of........................... 210,211

surveys in...........--.....--...--......-..--.-- 114

Alien, II. T., explorations by........................ 90,122

on geography................................ 43,84,88,92

Alsck River, course of, present and past. 272,285,290,293,294 

description of................................ 48,52-54,58

drainage system of (former), map showing...... 285

exploration of................................... 125,126

Ambler River, description of.........-...-...-....-- 97

American occupation, exploration under, history of- 119-132

309
310 INDEX.

Page. 

Amphibolite-schists, stratigraphic position of ...... 214-215

Anaktuvuk Pass, description of..................... 102

Anaktuvuk peneplain, age of........................ 288

Anaktuvuk Plateau, altitude of.............. 46,268,288,294

drainage of....................................... 100,101

location and general features of.......... 46,102,268,288

origin of..................................... 279,288,294

structure of...................................... 280

view showing................................ 260

Anaktuvuk River, description of.................... 102

geology of region near........................... 223

Anaktuvuk series, age and distribution of... 206 (table),237 

Andesitic rocks, occurrence of....................... 250,251

Anvik, climatic records from................ 158-170,175,189

climatic records from, period covered by........ 138,189

location of....................................... 138

Anvik River, description of......................... 91

navigation season on............................ 175

Apoon Pass, description of......................... 79,81-82

discharge at..................................... 66

Archean rocks, character and distribution of........ 205,

200 (table), 208,210,249,251,258,263 

Arctic coast, climate of.................. 141,146-147,153-154

climatic records from stations on.... 138,158-170,173,197

marine terraces on............................... 283-284

topography of.............................. 18,25-26,283

Arctic coastal plain, description of.................. 46,268

Arctic Ocean, drainage into............... 48,95-103,269,284

overland trip to.......-......-.------...-------. 125

tidal currents in................................. 26

whaling industry in............................. 116-117

Arctic River, location of............................. 95

Arctic Slope province, description of........... 17,46-47,267

physiographic relations of....................... 17,46

subdivisions of............................. 17,46-47,268

unmapped areas of---.....--------.--....------- 12

Area of Alaska, comparison of, with that of United

States, map showing.................. 15

Areas surveyed, map showing..-.....--------....... 131

Army officers, exploration by....................... 120,

121,122,124,125,126,127,128,130,131,132 

government by..........------.......----------. 119

routes established by......... 30,55,56,84,91,127,130,132

weather records kept by......................... 133,135

Army posts, establishment of ...................... 119,127

Arteaga, Ignacio, expedition led by.................. Ill

Astoria beds, fossils in.............................. 243

Atka Island, climate of.............................. 151

climatic records from......... 148 (PI. XIX), 158-170,189

period covered by..-..........------.-...... 138

location of--.....___-------........--------...... 138

Attu Island, climate of.............................. 151-152

climatic records from.................... 158-170,173,189

period covered by.......-.--.-....-.-------. 138

location of---.......---.---...-.......-----...... 13S

Aucella beds, age, range of........................... 235

distribution of................................... 234-235

occurrence of, in Koyukuk series................ 237

on Yukon River............................. 235

Augustine Volcano. See Mount Augustine.

Austin, O. P., on fur-seal fisheries................... 27

Azacharak Hill, discharge measurements at........ 65

B.

Baird Mountains, description of..................... 44-45

drainage of...................................... 97,99

Baker, Marcus, cartographic work done by......... 120

Baker, Marcus, and Dall, W. H., bibliography by... 104,298

Page.

Baker, Marcus,and DaII,W. H.,on Mount St.Elias. 124 

weather observations compiled by.............. 134,135

Baker Creek, description of.......................... 87

Bancroft, II. II,, history of Alaska by, mention of... 104 

Baranof, A. A., work of, as director of Shclikof Company ................................... 113-114

Baranof Island, description of....................... 19

Russian settlement of........................... 20

section across.......................... 254 (PI. XXVII)

Barnard, E. C., work of...................... 13,127,129,298

Barrow. See Point Barrow.

Barter River, drainage basin of..................... 103,262

Basaltic rocks occurrence of.................... 220,250,251

Basargin, Vladimir, survey by....................... 117

Base-levels of erosion, ancient, correlation of........ 272,

277,286-290,293 

plates showing................................... 256,260

Basin lowlands, features of.......................... 281-283

sketch of, on Fish River......................... 282

type of, plate showing........................... 282

Bassanof, , Copper River visited by........-.-.. 114

Bassof, Emelian, fur-hunting expeditions of......... 107

Bates Rapids, description of........................ S5

Bathhouse River, drainage basin of................. 262

Batzulnetas River, location of...................... 55

Bays, opening and closing of, table showing......... 176

Bean, Edmund, journey by......................... 121

Beardslee, L. A., native opposition to exploration

overcome by........................... 121

Beaver Creek (tributary of Kobuk River),location of. 97 

Beaver Creek (tributary of Yukon River) .location of. 77 

Becker, G. F., investigations by.-........--....--... 126

Beechey, F. W., coast charting by................... 115

Belcher, Edward, cruise by.......................... 124

Bell River, portage route to Rat River from........ 76

Beluga River basin, lignite beds in.................. 240

Bendeleben, Otto von, exploration by............... 118

Bendeleben Mountains, altitude of.................. 39

drainage of.....--.--....--------...-.---..----.. 93

glaciation in..................................... 247

Bennett, Lake, abandoned valley near.............. 67

location of....................................... 66

Bergman series, age, character, and distribution

of ...............................206 (table),237

Bering, Vitus, explorations by.......... 106-107,124,132,202

Bering Island, Bering shipwrecked on............... 107

climatic records from........................ 158-170,189

period covered by............................ 138

location of....................................... 138,189

Bering Sea, climate of........................... 146,152-153

coast of, marine terraces on..................... 284

topography of...................... 18,23-25,283-284

volcanic rocks on............................ 206

See also Bering Sea coast climatic province.

drainage into.............................. 59-95,268-269

ice in.......................................... 27,140,153

islands of........................................ 26-27

tidal currents in................................. 26

Bering Sea coast climatic province, climatic records

from stations in. .. 138,158-170,173,190,191,197 

extent of......................................... 141

sea ice in...................................... 27,140,153

Bering Sea Islands, climatic province of, extent of... 141 

climatic records from stations in................ 138,

158-170,173,176,192,198 

features of....................................... 26-27

volcanic rocks of................................. 251

Bering Strait, discovery of.......................... 106
INDEX. 311

Page. 

Bering Strait, exploration of........................ 109

oceanic current in................................ 26

visibility across.................................. 104

width and depth of............................. 16,26-27

Bering-Arctic watershed on Howard Peninsula, description of............................ 92-93

Bethel Mission, climatic records from............... 158-170

climatic records from, period covered by........ 138

location of....................................... 138

Bottles series, age and stratigraphic place of..... 206 (table),

215,221

Bibliography of geographic and geologic literature.. 298-308

Big Salmon River, description of.

Billings, Joseph, voyages of. --.-........-......-.---

Birch Creek, description of ..........................

fossiliferou s limestone on........................

gold mining on...................................

67

113

76-77

213

77

95

116

118

Birch Creek schists, age and character of ....... 206 (table),

213,214,215,218,220 

Black River, description of.......................... 75

Blake, T. A., geologic work by...................... 201

Blake, W. P., reconnaissance by .................... 117

Blossom (H. M. S.), voyage of....................... 115

Bluefisli River, location of........................... 75

Bluestone, River, description of...................... 94

Bluff Point, slfales at................................ 240

Bodega y Quadra, discoveries of................. 109,110,111

Boundaries of Alaska, statement of................. 14

Bowlders, ice-borne, occurrence of................... 248

Bremner River, location of..-........-...-....-..--- 56

Bristol Bay, description of-.-..-.-...-...-..--.-..-- 23

drainage into.................................... 59-61

exploration of.................................... 109,115

British Columbia Plateau, location of............... 37

British explorers, work of........................... 119

British Mountains, description of................. 43,44,103

British sovereignty claims, basts of................. 110

Broca, George, explorations by...................... 124

Brooks, A. H., on geography and geology.-....-.-.. 24,

35, 50, 52, 53, 58, 62, 70, 82, 84, 86, 92, 206, 210, 

211, 212, 214, 216, 217, 219, 221, 222, 226, 231, 232, 

234, 235. 241, 242, 245, 246, 247, 251, 278, 284, 295

work of....................... 35,127,128,129,130.131,289

Buckland River, description of....................

exploration of. .................................

location of.-._._-..-._.....--_-.--....-.....-.- 

Buckley. C S., surveys under.....................

Cable, ocean, connections of..................... 132 (note).

Cache Creek, exploration at......................... 260,2B2

Cache Creek group, age and correlation of ....... 206 (table)

Cambrian rocks, occurrence of.................. 20fi (table),

210,211,212,213,214, 215, 216,218, 220,256,259 

Camden Bay, location of............................. 26,103

Camp Oolonna, climate at. --.-......-......-.-....-. 155,156

climatic records from.....................158-170,173,189

period covered by............................ 138

location of....................................... 138

Camp Pavidson, climate at ......................... 155.156

climatic records from................ ... 158-170,173,190

period covered by............................ 138

location of-................-....--..-...,-.....-. 138

Campbell, Robert, explorations 'of................... 70,117

Canadian Geological Survey, work of................ 203

See also Dawson, G. M., find McConnell, R. G. 

Canning River, description of........................ 103

Page. 

Cantwell, J. C., explorations by..................... 123

on Hotham Inlet................................ 96

on Kobuk River................................. 98

Cantwell conglomerate, age, character, and distribution of..................... 206 (table),219,241

Cantwell River, coal beds on......................... 87,241

description of.................................... 85-86

geology of region near....................... 209,241,257

survey of......................................... 130

Canyon Creek, location of........................... 94

Cape Beaufort, coal-bearing rocks at................ 233

topography of shore near........................ 25

Cape Belcher, topography of shore near............. 25

Cape Collie, tidal estuary near....................... 100

Cape Darby, topography near._..___._.,........._._ 93

Cape Kspenberg, rivers west of...................... 95

topography near................................. 25.95

Cape Fairweather, topography near................. 52

Cape Hope, coast line near........................... 100

Cape Krusenstern, location of ....................... 25

Cape Lisburne, carboniferous rocks near............ 217

cowl horizon at................................... 242

fossils from, age of............................... 241

old peneplain near............................... 279

structure at..................................... 260

surveys at....................................... 13,129

topography near.............................. 25,100,279

Cape Mountain, sketch of............................ 280

Cape Nome, topography of coast near............... 24

Cape Prince of Wales, coast charting near........... 115

fossiliferous rooks near.......................... 217,221

topography of coast near...................... 24-25,280

Cape Rodney, topography of coast near....-....-... 24

Cape Smyth, weather records kept at............... 134

See also Utkiavi. 

Capo York, topography of coast near............... 24,280

Capital Mountain, altitude of....................... 32

Carboniferous fossils, occurrence of............. 206 (table),

210,217,222,223,224

Carboniferous rocks, character and distribution of.. 206

(table), 208,214,215,217,218,

219-225,229,230,254,256,259.

correlations of............................... 200 (table)

formations composing....................... 206 (table)

intrusives in.......-..-..-..-.-.--.-..-.--.-..--. 250

mapping of...................................... 205

stratigraphy of.................................. 221-225

summary of..................................... 224-225

unconformity in. -......--.-.....-....--.......-. 223

Carboniferous times, history of...................... 265

Carey Creek, structure near......................... 262

Caribou Pass, description of........................ 35,57,58

Caribou River. See Cutler River.

Carinack, G. W., gold discovery by.................. 126

Carinel mission, climate at.......................... 153

climatic records from................ 158-170,173,176,190

period covered by............................ 138

location of....................................... i;«,190

Carter, F. G., explorations by....................... 260-261

Carter Pass, altitudes at............................ 261

rocks near-...................................... 262

Cartographic catalogue, preparation of.............. 298

Cartographic data, sources of....................... 296-298

Casadepaga River, description of....--...-....-..... 94

Cassiar gold district, location of..................... 49

Castner, J. C., explorations by...................... 128

on Goodpaster River............................ 84

.Cenozoic fossils, occurrence of- 206 (table), 236,238,240,242,243
312 INDEX.

Page. Page.

Cenozoic rocks, description of....................... 237-249 Civil code, enactment of............................. 120

Census Office, map published by ..-....-...--.---.-- 121 (Mark, Lake, altitudes near......................... 34

Central Plateau region, description of................ 17, location and general features of ................ 59,60,61

36-42,104,258-259,267,268,276-277 origin of- ..-....--..--..-..-........--..----..--. 283

forests in........................................ 41-42 Clark Peak, location of.............................. 68

Chagavenapuk River, locationof..-..-..-....--.--.- B3 Clarke, F. \V.,on Yukon River water................ 80-81

Chamisso, L. A., early notes on Alaskan natural his- Climate, comparisons of ............................ 11,144

tory by...-..---..--.-----..-....--....-----.-- 201 data concerning, sources of...................... 134

Chandlar Lake, exploratory trip to................... 123 features of, by provinces......................... 148-157

glacial origin of.................................. 283 general features of............................ 11,144-148

location of-..-----------.--.--..-.......---..-... 70,101 interests affected by............................. 133

Chandlar River, description of...................... 76 observations concerning, methods of............ 134-137

explorations on.......................... 103,129,207,261 section on....................................... 133-200

geologic structure on. ........................... 260 Climatic provinces, description of................... 140-141

glacial deposits in valley of-,....-..-.....-.--.-- 247 Climatic tables, description ot............... 137-140,177-178

granites and schists in valley of................. 210 Coal, occurrence of. ... 87,200 (table) ,237,233,239,240,241,242

Charlie River, location of............................ 74 supply station for, at Unalaska.................. 22

Chatham Strait, glacial action in.................... 246 Coal-bearing beds, occurrence of..................... 87,126,

location of....................................... 19 206 (table) ,208,219,232,233,236-242

Chedotlothna River, description of.................. 63 Coal Harbor, climate at.............................. 150

Chcna River, description of.......................... 85 climatic records from .................... 148 (PI. XIX),

navigability of................................... 87 158-170,172,176,186-188,190

Chernofski, climatic record from.................... 190 period covered by............................ 138

Cheshina River, location of.......................... 55 location of....................................... 138

Chetaslina Rh'cr, location of........................ 55 Coast, general features of............... 17-18,23,104,267-268

Chibukak. See Oambell. mapping of, work done on....................... 119

Chichagof Island, description of..................... 19 topography of.......................... 18,23,24,283-284

Silurian fossils on................................ 211 northern Alaska, plate showing............. 24

Chignak Bay, coal horizon of........................ 241 southern Alaska, plates showing............ 18,20,22

Chilkat, climatic records from....................... 190 Coast and Geodetic Survey .weather records kept by 134

Chilkat Indians, fur trade interests of............... 67-68 work ot ................. 119,120,124,125,127,132,134,201

Chilkat River, description of.................... 48,50-51,58 Coast Range, altitudes of............................ 19

Chilkoot, climatic records from...................... 171,190 base-level marked by summits of............ 286,287,288

Chilkoot Indians, opposition of, to immigration.... 121 description of.................................... 28-29

Chilkoot Pass, altitude of........................... 51 drainage of.................................. 29,51-52,55

route over........................... 51,67-68,121,125,128 erosional origin of............................... 270

Chilkoot River basin, explorations in................ 122 glaciation in..................................... 246

Chipp River, descent of.............................. 123 intrusive rocks of.................... 204,253,255,258,266

description of.................................... 101 date of intrusion of.............. 206 (table) ,254,266

outlets of, locationof. .......................... 26 peneplain remnants in....................... 286,287,288

Chirikof, A. I.,discoveries of........................ 107,132 routes across.................................... 51,64

Chisna group, age and stratigraphic place of. 206 (table), 219 structure section through.............. 254 (Tl. XXVII)

Cbjsana River, description of....................... 82-83,87 summits ot, altitudes of......................... 286,287

Chistochina River,course of......................... 55 plate showing................................ 256

geology of region at headwaters of....... t ...... 256-257 trend of.......................................... 268

Chitanatala Mountains, location of.................. 39 uplift of area covered by, character of........... 271

Chititia River, description of....................... 55,87,207 Coastal plains, description of................... 39-40,81,281

faulting in valley of ............................. 256 Coastal tundra belt, features of.......... 47,63,90,92,100,147

mouth of, location of............................ 87 Code of civil law, enactment of...................... 120

section across valley of................ 254 (PI. XXVI t) Coldwater group, age and equivalents of......... 206 (table)

stratigraphy in valley of......................... 206,207 Collier, A. J., on geography and geology........... 46,92,146,

Chitistone limestone, age and character of...... 206 (table), 208 (table) ,210,216,220,223,224,

219,222,229,230,256 ) 233,235,236,242,278,279,292,295

Choris Peninsula,location of....................... 25 weather observations published by.............. 142,143

Christiania, climatic records from................... 142-143 work of....................... 13,127,1:50,207,236,241,298

Chuckchee Peninsula, position of.................... 16 i Collins, P. M. D.,telegraph project of................ 117-111

Chugach Mountains, altitudes of.................... 272,287 , Collinson, Richard, voyage by....................... 116

base-level marked by summits of............ 272,287,288 | Colville River, description of................ 48,98-99,101-103

description of................................... 29,30-31 j exploration of................................... 123,129

glacial actionin................................. 247 | navigation of......,.....'........................ 100

location of.....-..-..-..--.-.......-..---.-...--.. 29 i routes to.-..-..--.-...--..-.-...--........--. 100,101,102

routes over...................................... 5\i,130 , sources of....................................... 96,98,99

structure of.................... 229,253,254 (PI. XX VII) unmapped areas near............................ 12

summits of,plate showing....................... 256 I Colville series,correlation of................. 206 (table) ,244

Chulitna River, description of....................... 57,60 | ' deformation of.................................. 243

Circle,climatic records from............. 158-170,173,174,190 Commander Islands, climatic records from. See Berclimatic records from, period covered by......... 138 ing Island.

location of....................................... 138 Russian sovereignty over........................ 107
INDEX. 313

Page. 

Communication. See Navigation; Railroads; Routes

and trails; Telegraph lines. 

Conglomerates, basal, significance oi................ 263-204

Constructional plateaus, types of.................. 280-281

Contour lines, explanation of........................ 297-298

Controller Hay, coal at.............................. 240

location of....................................... 21

petroleum near.................................. 228

section from Tanana to................ 254 (Pi. XXVI [)

Convicts, importation of............................ 113

Cook, James, explorations of.................... 109-110,132

Mount St. Elias noted by........................ 124

sovereignty ceremonies by....................... ill

Cook Inlet, ash cone on, plate showing-............. 34

climate at........................................ 145,149

coal at........................................... 239

description of--..-.-.-......-.---.-.-.--.-..-.... 21

drainage into.................................... 57,58

exploration of................................... 12,109

forest growths at. ............................... 145

glacial action at................................. 247

gravel benches at................................ 249

route traverse from.............................. 127-128

Copper Center, climatic records from.. ......... 158-170,191

climatic records from, period covered by........ 138

location of....................................... 55,138

Copper Glacier, description of....................... 55

Copper River, delta of.............................. 21,54,56

description of................................... 54-55,56

discovery of..................................... 110

drainage basin of............................... 48,58-59

exploration of....................... 122,128,129,130,207

mountain erosion by......................... 58,272,287

route traverse of................................. 127-128

routes to or along.............................. 56,83,84

valley of, antecedent character of............... 287

Copper River basin, basaltic flows in ............... 250

description of................................ 54-56,58-59

glacial action in.................................. 247

origin of......................................... 286,287

sedimentary rocks in............................ 229,249

stratigraphy in.................................. 208

surveys in................................... 128,205,207

uplift and deformation in........................ 291

volcanic rocks in............................. 225,241,251

view of..........-...-----.....--------....... 32

volcanism in................................. 225,241,250

Copper River Plateau, climate of.................... 145,155

climatic province of..-.....-....-...-.-.--....... 141

records from..... 138,159-161,163-165,167,169,170,191

description of............................... 30-31,54,268

drainage of..................................... 58-59,85

glacial action on................................. 247

northern margin of, plate showing.............. 42

origin of...-....-.--........----.--...-...------. 280

silt deposits of, plate showing................... '250

traverse across.................................. 127-128

Corals, Devonian, occurrence..---....-.----.-....... 205

Cordillera, correlations of, formations of............ 203-204

creseentic sweep of, import of................... 267

Cordilleran Glacier, influence of, on topography. 246,295-296 

Correlation, stratigraphic, table showing........... 206

table showing, discussion of..................... 206-207

Corwin Bluff, coal-bearing rocks near............... 233

Corwin series, age and distribution of.... 206 (table), 232-233

Cosna River, description of.......................... 86-87

portage route from.............................. 62

Cossack adventurers, explorations by............... 10,5-106

Page. 

Cotter, R. D., exploration by........................ 118

Cretaceous coal, occurrence of....................... 241

Cretaceous fossils,occurrence of.. 206 (table), 234-237,242,292 

Cretaceous rocks, character and distribution of.... 203,205,

206 (table),208,220,222,225,226,230,231,232,

234-237,239,242,250,252,254,255,259,263,279

intrusions in..................................... 250

structure of...................................... 258,259

summary of..................................... 237

Cretaceous time, metamorphism during............. 291

sea invasion duri ng.............................. 266,290

Cripple River, location of............................ 94,95

Cross Sound, climate near........................... 145

drainage west of................................. 52

explorations near................................ 107,109

orographic features near......................... 29-30

Croto River. See Peska River.

Crustal movements, history of .. 202,256,258,264-266,290-295

Cutler River, location of............................. 99

D.

Dadina River, location of........................... 55

Dadina schists, age arid distribution of...... 206 (table), 212

Dagelet, Lepante, on altitude of Mount St. Elias ... 124 

Dakli River, headwaters of, location of............. 97

Ball, W. II., on geography and geology.............. 88,104,

136,137,142,155,229,231,238,239,240,242,243 

researches by............................ 118,120,126,201

Dall, W. H., and Baker, Marcus, bibliography by,

reference to............................ 104,298

on Mount St. Elias.............................. 124

weather observations compiled by.............. 134,135

Dall, W. II., and Harris, G.D., on coal -bearing beds . 236,238 

Dall City, abandoned settlement at................. 77

Dall River, description of........................... 77-78

| exploration of.......-.-..............-.-.-.-.-.. 129

location of---.......-.-.-.-...--.-.---........... 90

' Dalton, Jack, explorations by.................... 51,125,126

Dalton Glacier, plate showing....................... 246

Dalton House, location of........................... 53,54

Darby Mountains, description of.................... 39

Davidof, G. 1., explorations by...................... 114

Davidson,George, investigations by................. 120

Davidson Mountains, location of -..---.............. 43

Dawson, telegraphic communication with........... 132

view of Yukon Valley at......................... 58

Dawson, G.M., on geography and geology of Alaska.. 16,

28,38,49, 65,203, 206,209, 211, 218,

225, 226-227, 238, 246,251, 284, 292

researches by................................ 125,201,203

Dcase, P. W., exploration by........................ 116

Dease Bay, drainage into............................ 101

Dease Inlet, location of.............................. 26,101

Deformation, epochs of.............................. 291

Delarof, E. I., Russian occupation claims presented

by...................................... Ill

Do Long Mountains, description of.................. 44,99

Delta River, cross section at......................... 205

description oJ................................... 35,84-85

metamorphic rocks on........................... 256

route traverse of.......................-.------.. 128

Densmore, Frank, explorations by_........----.-.. 120

Deposition, cycles of................................. 290-292

Dcshnef, Simeon, discoveries of...................... 106

Devonian coral reefs, extent of....................... 265

Devonian fossils, occurrence of.................. 206 (table),

207,208, 210, 219,220, 221,225,255,265
314 INDEX.

Page.

Devonian rocks, character and distribution of . . . 206 (table) ,

207, 208, 210, 211, 214, 215, 218-224,

226, 236, 252, 254, 255, 2.56, 259, 265

intrusives in... ....-..---.....................-.-- 250

mapping ol. .--.------------------.-------------- 205

metamorphism of .._..__.___.._.__--.--.---...... 218

Devonian time, crustal movements during-...------ 264-265

De Witt rain gage, use of ............................ 135

De^adeasli, Lake, location of... ...___.--------.....-. 53,71

Dickey, W. A., exploration by. ...................... 35

Dillingcr River, location ___........_...-.--..-------- 62

Diomede Islands, account of. ........................ 26, 106

Disenchantment Bay, gold seeker's travels from. . ..

location of... ..................................... 21

survey of. ........................................ 124

tide-water glacier on, plate showing ............. 246

Dixon, George, Mount St. Elias, noted by........... 124

Dixon Entrance, climate at. ......................... 144

timber limits near. .-..-....-.......-..--.-.-..... 29

Dog teaming, climatic limits of ...................... 147

Dome Mountain, altitude of... ....................... 73

Donjek Iliver, description of. .-.-.-.-.-------........ 70-71

view across.. ..................................... 280

Drainage systems, changes in. ............... 284-286, 293, 294

changes in, sketch map showing ................. 285

description ol. ....................--.-.--- 47-103, 268-269

development ol.. ......................... 284-286. 290-291

Dry Bay, location of. ................................ 52, 53

Dyea River, drainage basin of ....................... 29

Dyer, J. T., exploration by .......................... 118

Dynamic movements. See Crustal movements.

Eagle, climate at. ................................ 137, 155, 156

climatic records from ........................... 142-143,

148 (PI. XIX), 158-170, 173, 174, 191 

period covered by ............................ 138, 191

location of... ..................................... 138, 191

view of Yukon Valley at ......................... 78

Eldorado River, description of.. ..................... 94

Eldridge, G. H., on geography and geology. ... 30,57,219,240

work of... ................................. 35, 127, 128, 131

Elson, Thomas, coast charting by. ...,.'............. 115-116

Emerson, B. K., stratigraphic correlation by.. ...... 226-227

Endicott Mountains, base-level represented by summits of................................. 277.288

description of .................................. 43, 45, 268

drainage of. ...................................... 76, 90

exploration of. ................................... 129

glaciation in, plate showing. ..................... 248

north front of, plate showing .................... 260

Englacial deposits, composition of. .................. 244

English pioneer traders, explorations of. . . 64, 69, 105, 110, 120 

English explorations, summary of. .-..-----......... 119-132

Ennis, W. H., exploration by. ....................... 118

Enochkin formation, age and character of. .......... 231, 232

Enterprise (II. M.S.), voyage of. .................... 118

Eocene coal-bearing beds, distribution of. ........... 208

Eocene fossils, occurrence, of ......... 206 (table) , 238, 240, 242

Eocene rocks, character and distribution of . .204,206 (table) ,

219, 235, 236, 238-242, 243-244, 252, 278, 279, 290

deformation of ................................... 2.53

formations composing... . ........................ 240

fresh-water beds of.. ............................. 266

predominance of, in the Tertiary. ................ 205

stratigraphy of... ................................ 238-242

structure of.... ................................... 258

Page. 

Eocene time, history of.............................. 266,292

Erosion, cycles of ............................ 264-266, 290-291

Eschscholtz Bay, location of... ........--------.-.... 25, 95

Eskimo, coast habitat ol- ........................... 27, 82

fuel supply of, in Arctic Slope region.. ........... 47

hunting routes of... .............................. 102-103

relations of, writh other tribes.. ...-...---........ 91

See also Aborigines. 

Etivluk River, description of... ...................... 102

Etolin, A. K., explorations by.. ..................... 115

Evasha River, lignite outcrop on. ................... 262

Experiment station, agricultural, establishment of . 134 

Exploration, extent of, map showing- .............. 131

history of ........................................ 104-1 32

Extra-glacial deposits, composition of .............. 244

Extrusive rocks, occurrence of.... .. 204206 (table) , 250-251

See also Volcanic rocks. 

Eyak River, location of ............................. 56

Fairview River, location of .......................... 94

Fairway Rock, location of ........................... 27

Fairweather Mountains, altitudes of ................ 29-30

explorations of .......--.----.......-----........ 121

topography near. ................................ 270,271

Falls Creek, shale and coal beds near.. . .............. 239

Feather River, location of ........................... 94

Fenimore Cooper (schooner), voyage of ............. 117

Fickett River, location of ........................... 89

Fickett series, age and equivalents OL. .............. 206,

206 (table), 215,220, 259

character and distribution of ........ 215,220,223,224,259

Filippo, Filippi de, on Mount St . Elias .............. 272

Fiords, glacial erosion in. ............. 18-19,246,284,295-296

Fish Commission, coast charting by. ................ 119

Fish Creek, drainage area of ......................... 90

Fish River, basin lowland in valley of ............... 281-282

basin lowland in valley of, map of ............... 282

description of .................................... 93

navigation season on, table showing. ........... 176

Five Finger Rapids, cause of... ..................... 67

Fogs, areas of. .................................. 144,146,147

Forest fires, aboriginal indifference to ............... 42

Forests, character and distribution of ............... 29,32,

33,36,41-42,45,46,54,72,78,82,86,87,90,99,144-145,147

distribution of, map showing .................... 38

exploitation of ................................... 54

Formations. See Sedimentary rocks.

Fort Adams, climatic records at. See Tanana.

Fort Alexander, climate at .......................... 152, 153

climatic records from. ....................... 158-170,191

period covered by. ._._.....___...._.__..___.. 138

location of ...................................... 138

Fort Archangel Gabriel, destruction of .............. 114

Fort Constantine (Nuchek), climatic records from. 158-170,

172,196

climatic records from, period covered by. ....... 138

location of ....................................... 138, 196

Fort Egbert, climatic records from. See Eagle.

Fort Gibbon, climatic records from. See Tanana.

Fort Liscum, climate at. ............................ 148

climatic records from. ................... 158-170,172,191

period covered by ............................ i;jg

location of. ...................................... 138

See also Valdez. 

Fort Reliance, climate at ............................ 155, 156

climatic records from. ............... 158-170,173.174,191
INDEX. 315

Page. 

Fort Reliance, climatic records from, period covered

by ..................................... 138

location of ....................................... 138

Fort Selkirk, history of. ............................. 20,117

Fort Tongass, climate at. ........................... 148

climatic records from .............-.--------.... 142-143,

148 (PI. XIX), 158-170,171, 176,192 

period covered by ............................ 138

location of ....................................... 138

Fort Wrangell, climate at. .......................... 148

climatic records from ........ 142-143, 158-170, 171 , 175, 192

period covered by. ........................... 138

location at.. ..................................... 138

Fort Yukon, altitude of ............................. 129

building of ....................................... 117

climate at. ....................................... 155, 156

climatic records from ................ 142-143, 173, 174, 192

period covered by ............................ 138

location of. ...............-...---.--------.--...- 138

Fortymilc Creek, andesitic tufa near. ............... 251

description of .................................... 73-74

headwaters of, location of ....................... 84

surveys on ....................................... 129

valley of , view of .------------------------------. 92

Fortymile series, age and correlation of --....-. 206 (table) ,

214,215,218 

character and distribution of. ........... 212,213,214,220

Fossils, occurrence of, Carboniferous ........... 206 (table) ,

210,217,222,223,224 

occurrence of , Cretaceous .... 206 (table), 234-237,242,292

Devonian. .............................. 206 (table) ,

207,208,210,219,220,221,225,258,265 

Eocene...................... 206 (table) , 238, 240, 242

Jurassic. ......................... 228,232, 233, 234, 236

Miocene ...................................... 236, 243

Ordovician... ........ 206 (table), 207,208, 212, 217, 218

Permian......................... 206 (table), 222, 226

Pleistocene'..................... 227,246,249,272,295

Pliocene......................... 206 (table), 242, 243

Silurian. ................................ 206 (table) ,

208,210,211,215,216,217,218,252,255 

Tertiary............. 206 (table), 236,239,240,242, 243

Triassic .......................... 226, 229,231 ,234, 252

undetermined. ....................... 213,221,261,262

Fox River Valley, topography of, plate showing. ... 92

Frank Leslie's Weekly, expedition sent out by. ...... 125

Franklin, Sir John, explorations by ................. 115, 116

Franklin Mountains, location of ..................... 44,261

Franklin relief expeditions, explorations by. ...... .'. 116

Frazer Falls, location of ............................. 71

French sovereignty claims, basis of ................. 105,111

Frequency tables, object and use of ................. 177-178

Freshwater Bay, Silurian fossils at .--.------........ 211

Fresh-water deposits, occurrence of ................. 292

Friends' Mission, climatic records from. ........ 158-170,176

climatic records from, period covered by ........ 138

location of. -------------------------------------- 138

Frost, perpetual, depth of earth zone of......... 147-148,249

Frosts, last and first, records of, discussion of. ..... 137,139

records of, tables showing ....................... 171-174

Fur seals, breeding place of .......................... 27

Fur trade, aboriginal interests in.. 67-68,108,110,113,114,121 

inception of ...................................... 107-108

rivalry in. .......................... 105, 110, 117, 120, 121

Gakona group, age and distribution of... 206 (table), 241, 244 

Gakona River, location of ........................... 55

17211 No. 45 0(i 21

Gambell, climate at.......

climatic records from. 

period covered bylocation Of-....-.-----

Page. 

............ 153

158-170,173,176,192 

............ 138

............ 138

Gastineau Channel, shore topography at, plates

showing........----.------------..... 18,20,22

Geographic knowledge, development of............. 12,132

Geographic position of Alaska, world map showing. 14 

Geographic provinces, plates showing............... 16,28

Geography, general features of...................... 15-17

relation of development and.........-..--------- 104-105

work on, bibliography of........................ 298-308

Geologic history, review of.................. 263-266,290-296

Geologic map, description of........................ 204-206

Geologic structure, diagrammatic sections showing . 254 

Geological Survey, work of.. 120,124-132,134,201,206,passim

work of, map showing extent of................. 131

Geology, section on.................................. 200-296

works on, bibliography of....................... 298-308

Geomorphology, section on.......................... 267-296

Georgeson, C. C-, weather observations published by. 142 

Gerdine, T. G., work of................... 13,127,129,130,298

Gerstle River, location of............................ 84

Gibson, Arthur, acknowledgment to................ 103

Gibson, William, explorations by..---...-.---...... 117

Gilbert, G. K., on geology........... 227,244,270,272,284,296

Glacial deposits, occurrence of... 206 (table), 247,248,283,296 

Glacial geology, map showing....................... 244

Glaciation, character and extent of.................. 18-19,

50,52,55,85,244-249,261,270,271,280,283,284,290-291,296

plates showing................................... 246,248

Glacier Bay, description of.......................... 18-19

exploration of................................... 121

Silurian fossils at........................ 206 (table) ,211

Glacier Mountains, location of....................... 38

residuary origin of ............................ 275

Glacier Point, view up Matanuska Valley from..... 58

Glaciers, distribution of, map showing.............. 38

character and distribution of. .. 12,19,30,49,50,52,54,55, 

57,62-63,70,82,83,85-86, 87, 244-245, 247, 249, 271

neve fields of............................ 245,247,271,272

studies of........................................ 201

tide-water discharge cf......................... 19,52,57

types of, plates showing......................... 246,248

Glasanof, Andrie, explorations by................... 115

Glave, E. J ., explorations by........................ 125,126

Olenn, K. F., explorations by................... 127-128,131

Gneisses, occurrence of.......................... 203,

204,205,206 (table), 208,209,210,249,251,263-264 

Gold, discovery of........................ 77,117,121,125,241

sources of........................................ 213,218

Gold Ranges, location of............................ 38

Golikof, Ivan, fur-trading operations cf.------...... 110

Golofnin, V. M., investigations by................... 114

Golofnin Bay, topography of shore of ............... 24,93

Golofnin Sound, location of......................... 93

Goobic sands, age and distribution of....... 206 (table), 248

Goode, R. U., map description by................... 296-298

work of.......................................... 12,296

Goodhopc River, location of......................... 25,95

Goodpaster River, location.......................... 84

Goodrich, II. B., investigations by.................. 126

on Fortymile Creek.............................. 73

Gorman, M. W., acknowledgment to................ 60

Graham Island, lignite seams on.................... 238

Granite, occurrence of....................... 209,210,250,259

Grantley Harbor, drainage into..................... 94

topography of shore of.......................... 24
316 INDEX.

Page.

Gravel plateau at base of Alaska Range, plate showing 280 

Gravels, distribution of............................. 249

See also Pleistocene rocks. 

Gravina series, age and distribution of...... 206 (table), 220

Grazing, regions oJ............................. 36,51,87,147

Great Plains province, definition of................. 17

Greenville series, systematic affinities of ------------ 209

Grewingk, C., geologic mapping by.................. 201

on geology....................................... 201,217

Griffith, C. E., explorations by...................... 131

Ground ice, occurrence of........................ 147-148,249

Growing season, limits of.................... 139,150-151,181

limits of, tables showing......................... 171-174

Gulkana River, location oJ .......................... 55

Gwosdef, Michael, mainland discovered by ---------- 106

Owyndyr Bay, location of........................... 26

H.

Haidas, habitat and character of.................... 20,108

Hall Island, location of.............................. 27

Hann, J., on scheitelwerte........................... 177,184

Hanna, James, voyages of.......................... 110

Harbors, occurrence of.............................. 22,82

opening and closing of, table showing........... 176

Haro, Gonzalez, explorations by.................... ] 11

Harper, Arthur, explorations by.................... 120

Harpers Bend, location of........................... 87

Harris, G. D., and Dall, W. H., on coal-bearing beds. 236,238 

Harrison Bay, location of........................... 26

Hart, Fred, explorations by......................... 120

Hartman River, location of......................... 62

Hassan, A. F., cartographic work by................ 298

Hayes, C. W., on geography and geology............ 28,

37,49,67,245,246,251

work of.................................. 125-126,201,203

Hayes Riverbeds, age and distribution of... 206 (table), 240 

Help-me-Jack Creek, location of..................... 97

Herald (II. M. S.), expedition of...................... 95,116

Herendeen Bay. See Mine Harbor.

Herron, J. S., on geography........................ 39,63,86

work of.......................................... 35,131

Herron Glacier, description of....................... 63

Herron River, location of............................ 63

Hess, F. L., work of............................ 13,80,213,223

Hess, F. L., and Prindle, L. M., on Yukoii-Tanana 

stratigraphy...................................... 214

Hess Creek, location of.............................. 78

History of the Territory, summary of.............. 104-132

Hogatza River, location of........................... 91

Holiknuk River, location of......................... 63

Holiknuk scries, occurrence of....................... 236

Hollick, Arthur, work of.......................... 13,236,242

Holt, George, prospecting by......................... 121

Holy Cross Mission, climate at....................... 156

climatic records from........ 142-143,158-170,174,175,193

period covered by........................... 138

location of....................................... 138

Homan, C. W., observations by...................... 122

Hoola-IIoola River, drainage basin of............... 262

Hootalinqua River. See Teslin River.

Horsefly gravels, age and equivalents of ........ 206 (table)

Horses, use of, in exploration.................... 126,127,128

Hosiana River, location of........................... 77,78

Hot Springs, upland near, plate showing............ 40

Ilotham Inlet, topography near..................... 25

drainage into.................................... 96-100

Howard, W.L., explorations by..................... 123,12,5

Page. 

Howard, W. L., on geography ...................... 98,101

Howell, E. E., relief model by, plate showing......... 16

Howkan, climatic records from...................... 171,193

Hudson Bay Company, Alaskan pioneers of......... 120-121

exploration by................................ 76,116,117

Hunker series, age and stratigraphic place of........ 213-214

Hutlina Creek, description of........................ 87

Hyaks Creek, structure near......................... 262

I.

Ice,erosion by....................................... 52

limits of,in depth............................ 147-148,249

in navigable waters............... 27,137,140,149,153

tables showing.......................... 174-176

See also Glaciation; Glaciers. 

Icy Bay, sedimentary rocks on...................... 243

Igneous rocks, groups of............................. 204,205

occurrence oJ.................................... 202,203,

205,206,208,209,210,218,220,221,224-

225, 229, 249-252, 263-264, 265-266, 275

Ikogmut, climatic records from...................... 133,

148 (PI.XIX), 158-170,175,194 

climatic records from, period covered by......... 138

location of....................................... 138

Iliamna Lake, character and location of........ 59-60,61,283

Imuruk Basin (or Bay), drainage into.............. 94-95

topography near................................ 23,24

Inaru Eivor, description of.......................... 101

Indian pilots, employment of, on Yukon River...... 75

Indian River, description of......................... 72,73

Indian River series, stratigraphic place of........... 213

Indians, relations of, with Eskimos.................. 91

See also Aborigines and names of native tribes. 

Inglutalik River, location of......................... 92

Inmachuk River, location of......................... 25,95

Innoko River, features of.......................... 88,91,115

Interior climatic province, climate of............ 147,154-157

extent of......................................... 141

meteorologic stations in, location of............. 138

records from ............................... 142-143,

158,170,173-174,189-191,193,194 196,199 

periods covered by...................... 138

Interior lowlands, description of, in Central Plateau

region................................. 40

International boundary, location of................. 120,125

White River at.................................. 70

Yukon River at................................. 65

International boundary expeditions, weather records kept by........................... 134

Intrusive rocks, occurrence of....................... 203,

204, 205, 206 (table), 208, 209, 210, 218, 220,

232, 249-250, 231, 253, 255, 258, 263-264, 266

summary of...................................... 249-250

Investigator (II. M.S.), voyage of................... 116

Ipnechuk [Inmachuk] River, location of............. 25

Iskut River, location of ............................. 49

Itvelik River, situation of........................... 102

Jack River, survey of................................ 128

Jackson, Sheldon, weather observations made by.... 142

Jamestown (U. S.S.), intervention of................ 121

Jarvis, D. H., on geography.......................... 26,79

Jarvis River, location of ............................ 53

Jim River, headwaters of............................ 90

John River, course and character of................. 89,102

source of......................................... 102
INDEX. 317

John River, valley of, glaciation in.............. 244-245,247

valley of, glaeiation in, plate showing........... 248

metamorphic rocks in....................... 215

Johnson River, description of....--...-------.....-- 84

Jones River, description of.........-.......------...- 62

Juneau, climate at.....-----.......-.----..---.-.--.. 144,148

climatic records from............ 142-143,158-170,171,193

period covered by............-..-.---....--. 138

location of....................................... 138

marine bench near............................... 249

metamorphic rocks near......................... 255

shore at, plate showing.......................... 22

structure section at .................. 254 (PL X XVII)

topographic surveys near....................... 130

view from, showing dissected plateau........... 256

Juneau mining district, surveys of.................. 130,207

Juneau wharf, climatic records from............ 158-170,193

climatic records from, period covered by......... 138

location of....................................... 138

Jura-Cretaceous fossils, occurrence of........ 230,234,236,255

Jura-Cretaceous rocks, occurrence of............. 229,236,252

Jura-Cretaceous times, sedimentation during....... 266

Jurassic fossils, occurrence of............ 228,232,233,234,236

Jurassic rocks, occurrence of............ 203,205,206 (table),

208,225,227,228-236,239,252,257,266 

stratigraphy of.................................. 226-234

structure of...................................... 257-258

Jurassic times, deposition during.................... 266

intrusions during................................ 250,266

Jurassic volcanics, occurrence of..................... 250

re.

Kachemak Bay, coal measures of ............

Kaiyuh Mountains, drainage of..............

Kaiyuh River, description of................

Kaltag River, location of ....................

portage route to, from Unalaklik River . 

Kalzas Mountain, altitude of................

Kalzas River, location .. of..................

Kanauguk River, location of ................

Kanektok River, location of.................

portage route to, from Togiak Lake. 

Kantishna River, description of .............

Kanuti River, description of ................

portage trail to, from Tozi River ........

Kanuti series, correlation of.................

Karr, M. B., explorations by......__._....--

239

88,91

91

91

92

------ 95

...... 64

...... 61

...... 86

...... 90

..--.. 88

...... 220

-.-... 124 

Kasaan greenstone, age and distribution of. 206 (table),226

structure of...................................... 254

volcanic origin of.---....--...-.-......----...--. 250

Kaskawulsh River, description of._.._._......-..... 53

Katalla formation, occurrence of.................... 239

Katecl River, route to, from Buckland River ....... 95

Kaviruk River, description of.....-.....-.---------. 94

Kawanak Pass, discharge at........................ 66

Kayak Island, discovery of.......................... 107

location of-....-........-.-........-.-.-.....-.-. 21

Kellett, Henry, exploration by...................... 116

Kenai, climate at ---...-.......----.-......--.------. 148

climatic records from. 148 (PI. XIX), 158-170,172,176,194

period covered by........................... 138

location of....................................... 138

Kenai Mountains, description of.-......-.--.--..... 31

Kenai Peninsula, description of.................... 15,57,272

exploration of...----...--.----..----------...... 13, 111

temperatures of................................. 149

Kenai River, navigation season on, table showing .. 176

Page. 

Kenai series, age and atratigraphic place of ...... 206 (table),

240-241,243 

character and distribution of........................ 235,

236,238,240,242,243-244, 252 

Kennicott, Robert, scientific work of................ 118

Kennicott formation, age and correlation of.. 206 (table), 234 

occurrence of............................ 230,234,235,256

Ketchikan, climatic record from..................... 194

Ketchikan district, structure section in............. 254

Ketchikan series, age and distribution of-...-...-... 222,254 

equivalents of............................ 206 (table), 255

Ketchum, Frank, explorations by................... 118

Khwostof, N. A., explorations by................... 114

Kichaiak Creek, location of.......................... 97

Kigluaik Mountains, description of.................. 39

drainage of......--.-....-.--------.-....-...--.- 94,247

glacial ice in..................................... 245

residual nature of...-........-.---.-.........---. 275

section across.................................... 254

structure of...................................... 259

typical outcrop in............................... 216

Kigluaik series, age and correlation of........... 206 (table)

stratigraphy of.............................. 216,218,259

Kikiktak, climatic records from. See Friends' Mission. 

Killisnoo, climate at................................. 148

climatic records from..................... 148 (PI. XIX),

158-170,171,179,182,183,194-195 

period covered by............................ 138

frequency tables for, discussion of.... 178,180-181,183-184

location of...................................... 138

King Island, description of.......................... 27

King River Valley, wave-cut rock bench in, plate

showing........ L ...................... 278

Kiska Island, climate of............................. 151

climatic records from........................ 158-170,195

period covered by............................ 138

location of.--......-..--.....-.-....--.......---- 138

Kivalina River, location of.......................... 100

Kiwalik River, location of........................... 25,95

Klawasi River, location of........................... 55

Klehini River, description of........................ 50

trail along....................................... 50-51

Klondike region, frost zone in....................... 147

location of....................................... 72,126

routes to................................. 51,53-54,67-68

stratigraphy of, table showing................... 213

Klondike River, description of...................... 72-73

Klondike series, character and stratigraphic place of. 213 

Kloochman Canyon, location of-----...............- 49

Klotassin River, description of--...-...--..........- 70

Kluane Lake, description of....-.--.....-..........- 71

origin of......................................... 283

Kluane Kiver, description of........................ 71

Klukwan, navigation to..-......------..........-.-. 50

Klutina River, location of........................... 55

Klutina series, age and distribution of.......... 212,229,256

Klutlan Glacier, location of....---..-..-.-.......--. 71

Klutlan River, description of........................ 71

Knik Arm, drainage into............................ 58

Knik River, location of.............................. 58

Knowlton, F. II., lossil plants identified by.. 235,236,240,241 

Kobuk River, course and character of.... 48,96-97,98,99,284

lower gorge of, pla te showing.................... 282

navigation of......................... 98,123,129,215-216

routes to................................ 90,91,97,100,129

valley of, glacial action in....................... 248

lakes in...................................... 283
318 OTDEX.

Kobuk River, valley of, lignite-bearing beds in ..... 242

Kodiak, agriculture at. .....-...............-----.... 113

climate at. ................................... 145, 148, 149

climatic records from ............ 142-143, 158-170, 172, 195

period covered by -----.................-..... 138, 195

location of ....................................... 138, 195

surveys near ............-...............--------. 114

Kodiak Island, description of ....................... 21

forest growth of .,...----...............--------- 145

peneplain remnants on .......................... 272

settlement of .................................... 21, 110

Spanish exploration of .......................... Ill

Kodiak slates, age and distribution of .............. 232

Kogoluktuk River, location of ...................... 97

Kok River, cuitl horizon at .......................... 242

Kokotena River, description of .............--.---... 89

Kolmakof , Alexander, explorations by .............. 115

Kolmakof, climate at .---------.---..-.---.---------- 156

climatic records at ................... 158-170, 174, 175, 196

period covered by .----......-.-......-.-..... 138

location of ...--...-...--.-....,------...--------- 138

Kolmakof series, occurrence of .............-.-.----. 236

Korsakof, Alexander, explorations by. .............. 115

Kotlo series, abandonment of name of ........... 214 (note)

Kotzebue, Otto von, voyages of ..................... 114,201

Kotzebue Sound, drainage into. ....-.-.....-------.. 95

explorations at and near. ........ 114, 115, 122-123, 129, 207

topography near. .....----....-------...-.---.--- 25

Kougarok River, location of ......................... 94, 95

Kouuk River, description of ......................... 93

Koyukuk Plateau, base-level of erosion marked by. . 277, 288 

Koyukuk River, basin lowlands of ................ 89-90, 282

description of .................................... 88-91

exploration of ....................... 115, 122, 123, 129, 207

routes to ............................. 76, 77, 91, 97, 103, 129

Koyukuk series, age and correlation of ...... 206 (table) , 237

Kramchenko, , explorations by . 

Krause, Arthur, survey and map made by . 

Krenetzin, P. K., exploration by ...........

Krusenstern, A. J. von, surveys by... .....

Krusenstern Island, location of ............

Kruzgamepa River, location of .............

Kruzof Island, location of. ...-.....-.......

Kugerack River, location of .

115 

122

... 108,109 

114 

26

... 93-94 

19 

96 

Kugruk River, location of........------....---...... 25,95

Kuiu Island, Cretaceous rocks on................... 208,239

features of....................-.----....---.-.... 19

Kuiu Mountains, gneisses in......................... 210

Kuk River, location of.............................. 100

Kukpuk River, description of....................... 100

Kulukak Bay, location of........................... 23

Kupowra River, location of......................... 100,103

Kupreanof Island, coal-bearing rocks of............. 238

location of........---------...-....-...------.-.. 19

Kushtaka formation, occurrence of.................. 239

Kuskokwim Bay, drainage into.................... 23,63-64

Kuskokwim Mountains, description of.............. 39,63

Kuskokwim River, basin lowlands of............. 40,62,282

course of, conditions determining........... 284,285-286

description of.........-.-......--.--...'......... 48,61-64

drainage basin of.--....-----.....-............. 59,61-64

East Fork of, character and course of.......... 61,62-63

exploration of ................................... 12,205

navigation of..................... 64,115,127,128,131,175

region of, sea invasion of........................ 290

valley of, glaciation in........................... 247

routes to.............................. 61,62,63,64,88

Section across................................ 254

Page.

Kuskokwim River, valley of, timber in............. 87

Kuskokwim-Skwentna divide, stratigraphy near.... 207

Kuzitrin River, description of....................... 94-95

Kuzitrin series, stratigraphic place of... 206 (table),216,218

structure of...................................... 259

Kvichak River, description of....................... 59

Kwik River, description of.......................... 93

Kwikli River, location of............................ 63

K \vikluak Pass, discharge at........................ 66

location of....................................... 79

Kwikpak Pass, discharge of......................... 66

identity of, with Yukon River, discovery of..... 118

Kwiniuk River, description of....................... 93

L.

La Perouse, J. F,, explorations by.................. Ill, 124

Ladue, Joe, explorations by......................... 120

Lake. See next word of name.

Lake schists, occurrence and stratigraphic place of.. 210,

214-215,218,220 

Lakes, geomorphology of............................ 248,283

Lava cones, location of...---..-.-----..........-.... 275

Lava flow, canyon in, plate showing................ 252

rapids caused by, plate showing................. 252

Lava plateaus, occurrence of........................ 280-281

Lawson, A. C., on Coast Range batholith............ 271

Learnard, II. G., explorations by...... -.......-.-... 128

Lebarge, Lake, description of....................... 66-67

Lebarge, Michael, explorations by................... 118

Ledyard, J ohn, Russians interviewed by............ 109

Lewes River, basin of, extent of..................... 65

canyon in, plate showing..---.....-.......-..... 252

description of.................................... 66-68

exploration of.................................... 121,125

rapids in, plate showing......................... 252

valley of, routes along-......................... 51,67-68

silt terraces in, plate showing............... 250

Liard River, headwaters of, location of............. 48-^9

route along...................................... 69

Libbey, William, exploration by.................... 124

Lignite, occurrence of. 206 (table),237,238-239,240,241,242,262 

Lisburne series, age and correlation of. 206 (table), 220,223-224 

Lisianski, Urey, surveys by......................... 114

Literature, geographic and geologic, bibliography of. 104,

298-308 

Little Canyon, location of........................... 49

Little Salmon River, location of..................... 67

Lituya Bay, description of.......................... 20-21

French possession of.'. ---.--.......-.......--.... Ill

lignites at-----.......----.-.......--............. 239

Lowe, P. G., explorations by........................ 128

Lower Cretaceous times, metamorphism during-..... 291

Lowlands, character and origin of................... 281-282

Luigi, Amedeo, explorations by..................... 124-125

Lutke, F. P., surveys by............................ 115,303

Lynn Canal, glacial occupation of................... 246

surveys near..................................... 125,129

timber limits near............................... 29

topography near................................ 19,28-29

3VT.

McClure, S. M., explorations under................... 116

McConnell, R. G., geologic contributions by......... 201

on geography and geology....................... 42,

68,69,72,74,75,76,125,213,214,233-234,263,277

McGrath, J. E., survey by........................... 125

on Mount St. Eltas.............................. 125

McLenigan, S. B., explorations by................... 98,123
INDEX. 319

Page. ; Pago.

McLonigan, S. B., onNoatak River ................. 46,88 Middleton Island, location of........................ 21

McQuesten, Jack, explorations by................... 120 Miles Canyon, description of......................... 67

Mackenzie, Alexander, explorations by.......... 112,115,132 plate showing.................................... 252

Macmillan Mountains, description of................ 68 Miles Glacier, location of............................ 56

Macmillan River, course of.......................... 68 Military posts, weather observations at.......... 133,134-135

Magnetic station, maintenance of, at Sitka.......... 115 Minehumina Lake location of....................... 63,86

Mahutzu River, location of.......................... 85 origin of......................................... 283

Makushin Volcano, location of...................... 22 Mine Harbor, climatic records from................. 158-170

Malakof, Vassili, explorations by.................... 115 climatic records from, period covered by........ 138

Malaspina, A. M., explorations of................... 111,124 location of....................................... 138

Mankomen group, age and distribution of..... 206 (table), Mineral output, growth of........................... 11

222,225 Mineral resources, investigation of.................. 126

igneous rocks in................................. 222,250 Mineralized rocks, occurrence of.....-....--.-..-.... 213,218

Manning Point, drainage at......................... 103 Mining development, furtherance of, by waterways. 47,64-65

Map, topographic, description of.................... 296-298 Minook Creek, location of........................... 78

Maps of the Territory, list of........................ 296-297 Mint River, location of.............................. 95

Marine benches, altitudes of......................... 249 Miocene fossils, occurrence of........................ 236,243

Marryatt Inlet, location of.......................... 100 Miocene rocks, occurrence of......................... 205,

Marsh, Lake, description of......................... 66-67 206 (table), 208,236,238,240,241,242-243,252,278

Marsh, S. J., acknowledgments to................... 260 stratigraphy of.................................. 242-243

explorations l>y.............................. 103,260-262 Miocene times, history of............................ 266

Martin, G. C., on geology...-.....-...-.. 228,231,234, 239,243 Mission Creek series, abandonment of name of...... 235

work of.......................................... 13 I Missionaries, arrival of.............................. 113

Martin, G. C., and Stanton, T. \V., on Alaska Penin- , weather records kept by......................... 133

sula.................................... 231 Mitkof Island, location of........................... 19

Martinet, Estcvan, explorations by................. Ill , Moffit, F. H., on geology...--...-.........--..... 92,216,228

Masons Narrows, topography near.................. 84 | work of.......................................... 13

Matannska River, description of.................... 58 Monadnocks, occurrence of.......................... 275,278

surveys of....................................... 127-128 Moore, T. E. L., exploration by..................... 116

tidal flats of..................................... 57,281 Moose Hide group, character and stratipjaphic place

valley of, bituminous coal in.................... 240 of...................................... 213

recent uplift in............................... 286 Morzhovoi, climate at............................... J50

view in, from Glacier Point.................. 58 climatic records from.................... 158-170,172,196

Matanuska series, occurrence of..................... 230,235 period covered by........................... 138

Mauncluk Elver, location of......................... 07 location of....................................... 138

Mayo. Fred, explorations by........................ 120 Moss, growth of.................................. 82,147,202

Mcade River, description of......................... 100-101 Mount Augustine, location of....................... 21,33

Melo?.i River, description of......................... 88 i Mount Blackburn, altitude cf....................... 32

gneisses near..................................... 210 j Mount Ball, altitude of.............................. 34

Mcndenhall, W. C., on geography and geology...... 25,30, j Mount Drum, altitude of............................ 32

31, 35, 44,54,77,84,90,92,96,98,206,212,215,216, j view of.......................................... 32

219, 220, 222, 228, 230, 241, 248, 257, 280, 281, 283,286 j Mount Kdgccumbe, location and character of..... 19,109,251

work of................... 13,127,128,129,130,207,217,298 Mount Eoraker, altitude of.......................... 34,272

Mentasta Pass, location of.......................... 36 description of.................................... 34-35

Mentasta scliists, age and correlation of......... 206 (table) origin of......................................... 273

Mesozoic fossils, occurrence of........ 206 (table), 226,228,229 Mount Gordon, altitude of.......................... 32

230, 231, 232, 233, 234, 235, 236, 237,241,242,252,255 Mount Hayes, altitude of............................ 35

Mesozoie rocks, occurrence ol.... 203,204,20.1-206,200 (table), I glaciers near..................................... 86

210,219,225-234,237,239,250,256-257,258,269 j Mount Hubbard, drainage near..................... 53

stratigraphy of.................................. 225-234 Mount Jarvis, altitude of............................ 32

subdivisions of.................................. 205 Mount Juneau, shore topography near, view of...... 20

Sec alKO Cretaceous, Jurassic, and Triassic. Mount Kimball, altitude of.......................... 35

Mesozoic times, deformation during................. 253 Mount Logan, altitude of............................ 30,271

Metamorphic rocks, age of........... 208,210,211,215-216,256 Mount McKinley, altitude of........................ 34,272

character and distribution of.................... 204, description of.................................... 34-35

205,210,211,234,250,256 drainage near.................................... 86

intrusives in..................................... 250 origin of...--...-.-.-.-..-.-..............--..-.. 273

Metamorphism, epochs of........................... 211,291 region near, topographic map of, plate- showing. 36

Meteorologic stations, alphabetic lists of........ 138,189-200 structure near................................... 257,258

location of........................... 133-134,138,189-200 surveys near..................................... 128,130

map showing................................ 136 view of-..--....---..--..---...--..-..---.---..--. 30

observations at.................................. 135,136 Mount Regal, altitude of............................ 32

periods covered by........................... 138 Mount Russell, altitude of........................... 34

tabulated records, of......................... 138, Mount St. Klias, altitude of......................... 30,124

142-143,158-176,179,182,183,185-200 character and origin of.......................... 272,273

Metlakatla, climatic records from................... 171,196 discovery of.....--..---..-.....-...-...--..--... 107

Mica-schists, occurrence of.......................... 203, marine fossils on............................. 249,272,295

206 (table),209,212-216,218,220,251,256 [ orographic features near......................... 29
320 INDEX.

Page.

Mount St. Elias, structure of ..-...-...-.---..--..-- 255 

view of.--..-..---..--..--..--..--..--.---.-.....- 30

Mount Sanford, altitude of.......................... 32

Mount Spurr, altitude of............................ 34

Mount Wrangell, altitude and location of........... 32

plate showing.................................... 32

Mount Zanetti, altitude of.......................... 32

Mountain passes. See Routes and trails.

Mountain ranges, axes of, plate showing............ 28

residual, origin of................................ 275

types of.......................................... 269

uplift of, discussion of................... 269-275,294-295

Muir, John, researches Toy........................... 121,201

Muir Glacier, exploration of......................... 121

Mulchatna River, location of..-...-...-.---..-...... 60

Muldrow, Robert, work of.................... 35,127,128,131

Murray, A. H., Fort "Yukon, built by................ 117

nsr.

Nabesna River, description of...................... 82-83,87

Nabesna series, character and distribution of. 206 (table), 222 

Nadina River, location of........................... 55

Nagaicf, Leontiy, Copper River discovered by....... 110

Nahoclatilten, fossil plants near..................... 241-242

Naknek series, age and character of................. 231,232

Nanaimo group, age and correlation of.......... 206 (table)

Nancy Dawson (yacht), voyaj ;of.

Nanushuk River, location of........................

Nanuslruk scries, occurrence of......................

Nasina series, character and distribution of.........

National Geographic Society, explorations under...

Native tribes, character of.......................... 20,82

Russian oppression of.--..--.--..--..--.---.. 108,110,113 

See also Aborigines, Eskimo, and names of Indian 

tribes.

Naval officers, explorations by .. 117,119-120,121,122-123,132 

government by.................................. 119

Navigation, courses and character of....--..-.. 22, 27,49,50,

57-58,59, 64, 65,67-68,69,71-72,75,76,78,

87, 91,92,98,101,102,104-105,115, 121,123,

127, 128, 129, 131, 144,146,147,175,215,216

season of, tables showing........................ 174-176

See vlso Routes and trails.

Navy Pass, location of.............................. 101

Near Islands, location of.-.--..--.---.---.---.---.-- 22

N6v« fields, location of...................... 245,247,271,272

New Archangel. See Sitka.

Nicola group, age and correlation of............. 206 (table)

Nikolai greenstone, age, character, and distribution

of........................ 206 (table),219,222-223,250,256

Nisconlith series, age and correlation of......... 206 (table)

Nisling River, source and course of.................. 71

Niukluk Kivcr, basin of, plate showing.............. 282

description of.................................... 93-94

Nizina River descent of............................. 126

source of...........-...--..-..--.....-..-..---.- 55

Noatak River, basin of, glacial action in............ 248

description of.................................... 98-100

drainage type of...--..---.--..--.----...-.-.--.- 48,284

source and course of........................ 96,97,99,123

timber on........-...-..--..--..--..--.---....... 46

trails to or along......................... 97,100,102,123

Nogheling River, description of..................... 60

Nome, climatic record from........--.--..--.--..... 196

lack of harbor at..-.....-..--..-..--..-..--..-.. 26

Nome gold field, survey of........................... 126,129

Nome region, frozen ground in, depth of............ 147-148

Page. 

Nome River, source of............................... 94

N ome scries, age and correlation of...... 206 (table) ,217,218

character and stratigraphy of............... 216-217,259

structure of...................................... 259

Nonushuk series, age and correlation of......... 206 (table)

Nootka Sound, Spanish-British controversy over... 111,112 

Nordenskiold River, source of....................... 71

North America, northwestern, geographic provinces

of...................................... 16

geologic sketch map of........................... 202

Northwest passage, first making of.................. 116

Northwestern Fur Company, explorations by....... 112

Norton Bay, coal-bearing beds of................... 242

drainage into.................................... 92-93

explorations near........................ 109,115,118,201

location of....................................... 23

Norton Sound, drainage into........................ 92-93

Nowi River, description of.......................... 88

Nuchek, climate at.................................. 148,149

climatic records from.................... 158-170,172,196

period covered by............................ 138

location of....................................... 138

Nugashik River delta, growing season at........... 151

Nulato, climatic records from............... 158-170,175,196

climatic records from, period covered by........ 138

location of....................................... 138

Nulato sandstone, age and character of............. 236

Nunivak Island, description of...................... 27

Nushagak, climatic records from. See Carmel Mission. 

Nushagak River, description of..................... 60

Nutuvukti Lake, outlet of........................... 97

Nutzotin Mountains, altitudes of................... 83

description of-..--.-.-.-.-..--..-...--..--..--..- 35-36 

drainage of..................................... 82-83,87

location of..................................... 29,35,273

peneplain represented by summits of............ 287,288

section across.................................... 254

structure of........--.......-..--...-...-...-.... 255,257

Yukon Plateau at, plate showing............... 276

O.

Ocean cable, connections of...................... 132 (note)

Oconnor Glacier, drainage from..................... 71

plate showing-................................... 24fi

Oconnor River, source of............................ 53

Ogilvie, William, on Porcupine and Yukon rivers... 65,74,75

surveys by....................................... 125

Oil fields, location of................................. 130,228

Oklune Mountains, Jura-Cretaceous rocks in........ 236

Oklune series, age and features of.................... 236

Okwega Pass, discharge at.......................... 66

Old Crow River, source and mouth of............... 75

Omalik, climatic records from............... 158-170,176,197

climatic records from, period covered by........ 138

location of....................................... 138

Orca, climate at...................................... 148-149

climatic records from........................ 158-170,197

period covered by............................ 138

location of....................................... 138

Orca scries, age and correlation of.............. 206 (table),

227,228,229,239 

Ordovician fossils, occurrence of...--......... 206 (table),

207,208,212,217.218 

Ordovician rocks, character and distribution of..... 20&

(table), 207,208,210-218,256,259
INDEX. 321

Page. 

Orogenic movements, extent and character of...... 269-275,

294-295 

Orographic provinces, definition of.....................27-28

Osgood, W. H., on geography....................... 34,60

3?.

Pacific coast, climate of.............. 133,140,144-145,148-149

climatic province of, extent of................... 140

records from stations in..................... 138,

158-172,176-185,191-195,197-199 

coal-bearing rocks of............................ 126,238

geomorphology of............................... 283-284

oilfields ol....................................... 130 i

shore topography of............................. 18 j

Pacific mountain system, base-level marked by l 

summits ol............................ 289 1

general features of...................... 16,28-36,104,267 ]

glaciers of.................................... 244-245,247

structure of...................................... 253-258 I

subranges of..................................... 268 '

Pacific Ocean, drainage into........................ 29,48-59 i waters of, temperature of....................... 140 1

Pah River, location of............................... 97,123

Palache, Charles, on Stepovak series................ 240

Paleozoic rocks, deformation ol..................... 203,213 ( occurrence ol............ 203,204.205-206,20« (tablo), 207, ,

208,210-226,229,230,232.233,252,254,256,258,259 

stratigraphy of.................................. 210-225 j

structure of.............................. 203,206,258,259 j

Palisade conglomerate, age and correlation of. 206(table),243 

Panhandle. See Southeastern Alaska. [ 

Pelly Banks, pioneer trading post at................ 69 (

Pelly gneisses, age and distribution of....... 206 (table), 251 I

Pelly River, location of............................. 65,68-69 |

Peneplains, ancient, correlation of............... 277,286-290 i

geologic history of........................... 286-290,293 \

Penny River, location of............................ 94

Peril Strait, description of........................... 19 \

Permian lossils, occurrence of............ 206 (table),222,226 j

Permian rocks, occurrence ol.................... 206 (table,

222,225,226,250,252,256 | 

Permian Sea, extent of.............................. 265

Perez, Juan, explorations by......................... 109

Pcska River, location ol............................. 57 !

Peters, W. J., on Colville River...................... 101 ' work of........................ 13,71,127,128,129,130,298 I

Petrof, Ivan, explorations by................... 104,121,132 |

Petroleum, fields ol.................................. 130,228

Pirn, Bedford, exploration by....................... 116 |

Pinguk River, location of............................ 95

Pinnacle system, occurrence of...................... 227-228 '

Pitmegea River, description ol...................... 100 j

Plants. See Forests; Grazing; Moss. | 

Plants, fossil, occurrence of...... 228,232,233,235,236,239-242

Plateaus, types of................................... 276-281 ]

types of,plates showing......................... 256,260

Pleasant River Valley, pass into.................... 62

Pleistocene fossils, occurrence of......... 227,248,249,272,295 [

Pleistocene rocks, character and distribution of.. 54,205,206, 

208,241,243,244,246,248-249.252,278,280,294-295 

delormationin................................... 294-295 ' grouping of...................................... 204 i

Pleistocene times, deposition during................ 291 I

Pliocene lossils, occurrence of........... 206 (table), 242,243 J

Pliocene rocks occurrence ol........................ 205,

206 (table),208,227,238,240-243,252,278 | 

stratigraphy ol.................................. 242-243

Plover (II. M. S.), expeditions of.................... 95,116 '

Page. 

Point Barrow, climate at.................... 146-147.153,154

climatic records from. 142-143,148 (PI. XIX), 158-170,200 

period covered by............................ 138,200

drainage near.................................... 100-103

explorations near........................ 115-116,123,129

location of....................................... 138,200

signal station at................................. 122

topography near.............................. 25,100-103

whaling station at............................... 117

Point Hope, climate at.............................. 154

climatic records from................ 158-170,173,176,197

period covered by............................ 138

location of....................................... 138

topography ol shore near........................ 25

Poling boat, uses of.................................. 74

Popof, Ivan, explorations by........................ 106

Population, growth of............................... 11

Porcupine River, description of..................... 75-76

headwaters of, location of....................... 74

survey of........................................ 125

Porcupine-Mackenzie divide, portage route over .... 233

Port Bncareli, survey ol............................. Ill

Port Clarence, climatic records Irom................ 142-143

drainage into.................................... 93-94

topography of shore near........................ 24

wave-cut rock bench at, plate showing.......... 276

Port Clarence limestone, age and distribution of. .20(> (table),

216-217,259

Port Etches, climatic records from. See Nuchek. 

Port Salety, topography of shore near.............. 24

Port Valdez, route Irom............................. 56,128

Portage Bay, climatic records from................. 190

location of....................................... 57,190

Portage routes. See Routes and trails.

Portland Canal, description of...................... 19

Post, W. S., work of................................ 127,128

Post River, description of...........................' 62

Post-Glacial uplilt, evidences of .................... 296

Powell, J. W., on geographic nomenclature......... 16

Precipitation, character of......................... 29,52,59

days of, tables showing............. 168-170,183,185,188

measurement of, methods of.................... 135-137

tables showing.......................... 162-170,189-200

discussion of................................. !39

typical monthly records of. plate showing...... 148

Pre-Glacial deposits, occurrence of.................. 244

Pribilof Islands, description of...................... 27

Russian landing at.............................. 113

Prince of Wales Island, description of............... 19-20

shore topography at, plate showing............. 20

structure section at............................. 254

surveys of....................................... Ill

Prince William Sound, aboriginal route to.......... 31

description of.................................... 21

drainage into.................................... 57

exploration ol................................... 109,111

forest growth near.............................. 32

glacial action in................................. 247

orographic features near......................... 29,30

Russian landing at.............................. 110

shipyard established at......................... 113

Prindle, L. M., on geography and geology.... 45,206,213,220

work of................................... 13,213,223,226

Prindle, L. M., and Hess, F. I/., on Yukon-Tanana

stratigraphy.......................... 214

Promyshleniki, predatory expeditions of............ 107-108

Ptarmigan Pass, location of...................... 35 (note)

Publications, geographic and geologic, list of........ 298-308
322 INDEX.

Page. 

Puget group, age and correlation of............ 206 (table)

Pullen, \V. J. S., explorations by.................... 116

Purcell, J. L., explorations by....................... 123

Purington, C. W., investigations by................. 126

Putnam, G. R., on Yukon River discharge.......... 65

Pybus Bay, Auoella from............................ 235

Pyramid Harbor, climatic records from............. 190

QQuadra, J. F., discoveries of.................... 109,110,111

Quartz veins, occurrence of...............20 i (table), 213,218

Q,uartKites, age and distribution of............. 20Pi (table),

212,214,216,218,256,259 

Quaternary rooks, occurrence of..... 20:; (table). 244-249,283

stratigraphy of.................................. 244-249

Queen Charlotte group, age and correlation of .206(table),226 

Queen Charlotte Islands, Spanish discovery of...... 109

It.

Railroads, routes of ....................... 51,54,57,64,67,84

Rainfall. See Precipitation.

Rainy Pass, location of........................... 35 (note)

Rampart, climatic records from.................... 158-170

climatic records from, period covered by....... 138

location of....................................... 138

structure at..................................... 282,295

surveys near.................................... 130

Kampart series, age and character of..... 206 (table), 214,220

occurrence of........................ 213,214,218,220,2SO

Ramparts of the Yukon, region near, description of.. 69,

78-79,92 

view of Yukon Valley at........................ 78

Kapid schists, character of.......................... 214

correlation of.................................... 215,218

Rat River, portage route to Bell Kiver from........ 76

Rattlesnake (II. M. 8.), wintering of, at Port Clarence ..................................... 116

Ray, P. IL, magnetic observations by. -..-..-...... 122

on Meade River................................. 100

Ray River, description of........................... 78

Raymond, C. \V.. Yukon trip of.................... 120,132

Reaburn, U. L., work of........ I3,35.89,l27,129!l30.l3l,298

Recent deposits, character of....................... 244

Recent lavas, occurrence of......................... 256

Recent marine fossils, occurrence of, on Mount St.-

Elias................................ 249,272,29."i

Recent volcanoes, distribution of................... 205

Reconnaissance work, progress of............... 130,132,202

progress of, map showing....................... 244

Redoubt Volcano, altitude of....................... 3.1

Redstone River, location of......................... 87

Reed, M. L., explorations by........................ 123

Reed River, location of.............................. 97

Reid, H. F., glacial studies by...................... 201

Eeliel model from base map, plate showing......... 11

Return Reef, explorations near..................... 115

Revenue-Marine Service, explorations by........... 119,

120,122-123,132 

Revillagigedo Islands, description of................ 19-20

Richardson, G. B., work ol......................... 127

Riley Pass, location oj.............................. 102

Rivers. See Streams.

Robertson Kiver, description of..................... 84

Kocky Mountains, description of................ 17,26,42-46

drainage of............................ 88,96,103,268,269

features of....................................... 268,269

geomorphology of.-......-...-..-.-...-..-.-...- 273-275

Page. 

Rocky Mountains, glacial action in................. 246,247

portage route through.......................... 233

section across.................................... 254,259

stratigraphy in.......................... 206 (table), 207

structure of..................................... 259-2f,3

summits of, plate showing...................... 2f 0

See also l-'ndicott Mountains. 

Kodgers expedition, exploration by................. 117

Rodney Creek, shore topography near.............. 24

Bonn, Oscar, explorations by....................... 130

on Triassic rocks................................ 230

Roim River, location of............................. 62

Romanzof Island, description of.................... 26

Romanzof Mountains, location of................... 44

Routes and trails, aboriginal courses of............. 31,

35, 50-51, 56, 58, 61, 64, 71, 74, 76, 82,

86,88,91,97,100,101,102-103,121,125

courses of, established by U. S. Arnry........... 30,

55,50,84,91,127,130,132 

to or via 

Alatna River............................ 90,129

Alsek Valley............................. 53-54

Ambler Hiver............................ 97

Bell River............................... 76

Bucklaud River......................... 95

Caribou Pass............................ 35,58

Chandlar River.......................... 76,129

Chilkat River............................ 50-51

Chilkoot Pass............... 51,67-68,121,125,128

Colville Valley....................... 100,101,102

Copper Kiver........................... 56,83,84

Cosna River............................. 62

Dall River............................... 129

Etivluk River........................... 102

Hogatf.a Kiver.......................... 91

Hosiana River........................... 77

Ilianm.i Lake............................ 60

Innoko Kiver............................ 88

Kaltag Kiver............................ 91,92

Kanektok River........................ 61

Kanuti River............................ 88

Kateel River............................. 95

Kichaik Creek........................... 97

Klehini Eivcr............................ 50-51

Klondike River................... Sl,SS-S4,67-<i8

Klutina River........................... 55

Kobuk River................... 90,91,97,100,129

Koyukuk River.............. 76,77,91,97,103,129

Kruzgarnepa Valley..................... 94

Kuskokwim River................ 61,62,63,64,88

Lake Bennett............................ 67

Lewes River............................ 51,67-68

Liard River.............................. 69

Mackenzie River......................... 233

Mentasta Pass........................... 36

Navy Pass............................... 101

Nizina River ............................ 126

Noatak River..................... 97,100,102,123

Northwest passage...................... 116

Norton Sound........................... 91

Nowi River.............................. 88

Porcupine River....................... 75,76,233

Port Valdez............................. 56

Rat River............................... 76

Reed River.............................. 97

Riley Pass............................... 102

Sinuk River............................. 94

Sixty-mile Creek.......................... 72
INDEX. 323

Page.

Routes and trails Continued. 

Courses of Continued, 

to or via 

Skolai Pass.............................. 126

Snag River.............................. 129

Stewart River.......................... 71-72,94

Stikine Valley........................... 49

Sushitna River.......-.-----.---........ 58

Suslota Pass............................. 30,122

Taku River.............................. 125

Tanana waters.................. 56,83,86,87,129

Teslin Lake.............................. 125

Thomson Pass.......................... 30,55,56

Togiak Lake............................. (il

T07J River............................... 88

Unalaklik River..--...-.-...-........... 91,92

Unimak Pass............................ 22

Unuk River.............................. 51

Valdez Glacier........................... 56,128

White Pass.............................. 51

White River.......................... 71,125,126

Yentna River............................ 58,128

Yukon Valley.......................... 51,56.. 63,

64-65, 68, 69, 72, 74, 75, 76, 77, 78, 84, 91, 92, 115, 121 

Zane Pass............................... 97

Roys, Captain, whaling voyage of..-..--...--.--..-. 116 

Rurik (brig), voyage of-..-...-.-...--.-...-.-.....-. 114

Russell, I. C., on geography and geology............ 30,

80,212,227,246,251,272,295 

work of...............-..---.....-.-...-- 124,125,201,249

Russell, Mark, explorations liy...................... 125-126

Russell Glacier, location of.......................... 70

Russian-American Company, charter privileges of... 113-

114,120 

explorations under.............. 111,114-115,119,132,201

fur-trade operations of.................. 112,113,117,120

Russian explorations, summary of.......... 108-109,119,132

Russian Mission, climatic records from. See Ikogmut.

Russian occupation, exploration under, history of.. 113-119 

Russian officials, weather records kept by........... 133

Russian traders, dealings with natives by... 108,110,113,114 

pioneer explorations of....................... 64,105-107

profits of.................................... 107-108,110

St. Elias Range, altitudes of........................ 70,245

description ol....................... 29-32,52,268,271-272

drainage of....-....-.....--....----..---........ 55,70

glaciers of.................-.....---.-.- 50,52,245,247,271

plate showing................................ 246

inland front of, plate showing................... 34

peneplain of..................................... 287,288

survey along..................................... 129

volcanic vent in...........---......--...--....... 251

St. Elias schists, occurrence of...................... 212

St. George Island, location of....................... 27

St. Lawrence Island, climate of. See Gambell.

description of...................---...----...--.. 27

discovery of..................................... 106

St. Michael, climate at........................... 146,152-153

climatic records from ........................... 142-143,

148 (PI. XIX),158-170,173,170,197 

period covered by............................ 138

harbor at........................................ 82

location of..................................... 23,82.138

Page. 

St. Paul Island, climate of........................... 152-153

climatic records from......... 148 (PI.XIX),158-170,198

period covered by.....--.._.....-.....-...... 138

location ol....................................... 27,138

Salcha River, location of............................ 85

Salmon, aboriginal dependence on................... 88

cannery of, on Yakutat Bay.................... 54

fisheries of, importance of....................... 20

Salmon River, description of........................ 75

Sands and gravels, distribution of................... 249

Sanford River, location of........................... 55

Sannak Islands, location of.......................... 22

Savaovik River, description of.............----..--. 103

Sawanukto River, description of.................... 103,262

Schanz, A. B., explorations by...................... 125

Scheitelwerte, definition of. ......................... 177

discussion of..................................... 184

Schistose rocks, age of............................... 218

Schists, occurrence of ................... 203,205,206 (table),

208, 209, 210,212-216, 218, 220, 223, 251, 256 

Schoonhaven, O. W. V., explorations by............ 131

Schott,C. A., weather observations published by. 134,135,136 

Schrader, F. C., on geography and geology.......... 38,

43, 45, 46, 76, 82, 88, 101, 206, 210, 214, 215, 220, 221,

223-224, 229, 231, 232, 237,242,243,244,247,248,250,

259, 260, 268, 273, 274, 275, 277, 279, 281, 288, 289, 292

work of............... 13,126,127,128,129,130,143,207,298

Schrader, F. C., and Spencer, A. C., on geography and

geology. .. 30,31,55,206,212,219,228,230,247,291 

Schuchert, Charles, Paleozoic fossils identified by.... 217,222

Schwatka, Frederick, explorations by........... 121-122,

124,125-126,132 

on volcanic tufa --..-------.-.--...-.-.----...... 251

Seacoast. See Coast.

Seal fisheries, importance of......................... 27

Sedimentary rocks, age of, range in............. 202,203-204

correlation of.................................... 203-207

table showing-............................... 206

Sedimentation, cycles of........_.................... 290-291

Selawik Lake, description of......................... 96

exploration of................................... 123

Selawik River, description of........................ 96

exploration of................................... 116,123

Selby, Lake, location of............................. 97

Selwyn River, description of........................ 69

Semidi Islands, location of.......................... 22

Serpentine River, location of ____.____._. ........... 95

Scton-Karr, II. W., exploratory trip by............. 124

Settlement, pioneer, location ol............ 20,21,69,104,110

Seventymile Creek, location of...................... 74

Seward, telegraphic connections of............... 132 (note)

Seward Peninsula, basin lowland on, plate showing. 282 

climate of........................................ 146,249

coastal features of............................... 23

plate showing................................ 24

drainage of...................................... 92-95

exploration of........... 108,115,116,118,129,130,205,216

gold fields of..................................... 130

granitic rocks in................................. 250

gravel deposits in...--....--.-........--....-.... 243

glacial ice on..................................... 245,247

lignite-bearing 1 >eds of........................... 242

marine erosion on........................... 249,279,280

position of....................................... 16

stratigraphy of.................................. 207,216

structure section of.............................. 259

topography of, plates showing.................. 40,02
324 INDEX.

Page. 

Seward Peninsula, upland of, description of......... 37

volcanic flows in................................. 250,251

wave-cut rock "benches on....................... 284

plates showing............................... 276,278

Shageluk Slough, location oi........................ 91

Shaktolik River, location of......................... 92

Shelikof, G. I., colonization by...................... 110

Shelikof Company. See Russian-American (Company. 

Shelikof Strait, location of.......................... 21

Shenandoah (private,er), captures by................ 116

Sheridan Glacier, drainage of........................ 56

Sheridan River, location of....-..-..-..-.-..-..-.... 50

Shevlin Creek, location of............................ 78

Shishaldiu Volcano, altitude of...................... 22

Shishmaref Inlet, shore topography of.............. 24-25

Shore line. See Coast.

Shore topography, types of................. 18,23,24,283-284

plates showing............................... 18,20,22,24

Shuinagin Islands, discovery of..................... 107

location of....................................... 22

Shuswap series, age and character of..... 206 (table),209,214

Siberia-Alaska Railway, tunnel requirements of.... 27

Siberian coast, visibility of, across Bering Strait..... 104

Signal Service stations, maintenance of.. 122,132,133-134,135 

Silokh River, location of............................. 85

Silt deposits of Copper River Plateau, plate showing. 250 

Silt terraces at White Horse, plate showing......... 250

Silurian fossils, occurrence of................... 206 (table),

208,210,211,215,216,217,218,252,255 

Silurian rocks, occurrence of......................... 205,

206 (table),211-218,220,221,223,256,259 

Silurian times, sedimentation during................ 204

Simpson, Thomas, exploration by................... 116

Shnpson Pass, location of........................ 35 (note)

Sinuk River, description of.......................... 94

Sischu Mountains, location of....-...-.....--.-.-... 39

Sitka, capital established at......................... 20,114

climate at................................ 144,148,149,151

climatic records at.................. 115,135,142-143,148,

(PI. XIX), 158-170,171-172,177,178,185,198 

period covered by............................ 133,138

location of....................................... 20,138

magnetic observations at........................ 115

structure section at.................. 254 (I'l. XXVII)

Sixtymile Creek, description of...................... 72

Skagit series, age, and correlation of........... 20i> (table)

stratigraphy of..................'.... 21:>,218,221,223,259

Skagway, climate at................................. 148,149

climatic records from.................... 15S-170,171,199

period covered by............................ 138,199

location of....................................... 138,139

telegraphic connections of....................... 132

Skagway-River, description of-.-..-.-...-..---..... 29,51

Skolai Mountains, altitudes of....................... 31

base-level marked by summits of................ 287

drainage of........-..--....--.--.--.....-....... 55,82

Skolai Pass, location of.............................. 70,126

Skwentna River, cross section at............ 205,232,254,257

lignite beds on................................... 240

Skwentna series, age and distribution of....... 206 (table),

232,257-238 

Skwentna-Kuskokwim divide, stratigraphic sequence

near................................... 207

Slana River, location of............................. 55

Slims River, location of............................. 71

valley of, view of, Oconnor Glacier from........ 246

Smith, E. E., surveys by........................... 118

Smith Bay, location of.............................. 26,101

Page. 

Snag River, survey of............................... 128-129

Snake River, location of............................. 94

Snider Peak, altitude of............................. 32

Snow fields, distribution of, map showing........... 38

Solomon River, course of...........----..-..-....... 94

Soolukpowaktoark River, exploration of............ 123

Soonkakat Hiver, location of........................ 88

Spanish sovereignty claims, basis of............. 109,110,111'

Spencer, A. C., acknowledgment to.................. 207

on geography and geology............... 206,280,288-289

work of................................... 13,127,129,249

Spencer, A. C., and Schrader, F. C., on geography and

geology... 30,31,55,200,212,219,228,230,247,291 

Spurr, J. E., on geography and geology............. 38,

60, 61, 02, 206, 207, 210, 212,213,220,223,

231,232,235,236,243,245,247,251,278,283

work of................................... 13,126,127,128

Squirrel River, location of........................... 97

Stanton, T. \V., on Aucella.......................... 234,235

work of....................................... 13,232,236

Stanton, T. \V., and Martin, G. C., on Alaska Peninsula.................................... 231

Stciger, George, analysis of Yukon River water by.. 80 

Steller, G. W., early geologic investigation in Alaska

by..................................... 200

Stcpovak series, occurrence of....................... 240

Stewart River, description of........................ 71-72

route to......................................... 71-72,94

Stikino River, course of, conditions determining..... 280,287

course of, description of ................... 48-49,58,284

drainage area of................................. 29

reconnaissance on............................... 117

route along...................................... 49

tributaries of.................................... 49 

valley of, character of............................ 49,271

Stikine Sound, features of.--.-......-.-......-...... 49

Stone, R. W., on coal measures...................... 239

Stoney, G. M., explorations by...................... 123

on geography and geology......-.-.-.... 44,45,96,98,101

Stratigraphy, discussion of.......................... 203-253

tables showing....................... 206,213,214,224,232

Streams, courses of, changes in...................... 284-285

courses of, changes in, sketch map showing..... 285

economic importance of......................... 47

ice closure of..................................... 137

opening and closing of, tables showing dates of... 174-170 

Structure, geologic, cross sections showing, location

of.................................. 253,257,258

outline of........................... ............ 252-263

plate showing.................................... 254

trend oi.......................................... 203,253

Stuver series, age and correlation of. - 206 (table), 21.5,220,224 

character of...................................... 219,220

Submergence, cycles of.............................. 290-292

Sunrise series, correlation of......................... 228-229

Sunset Pass, fossils near............................. 261

Sulphur (II. M. S.), cruise of........................ 124

Superior (whaler), successful voyage of............. lie

Surveys, character of, in certain areas. _............. 205,207

difficulties of..................................... 132

extent of......................................... 12,127

map showing................................ 131

history of........................................ 104-132

methods of...................................... 123,130

Sushitna River, description of....-.-.-.-.--......... 57-58

drainage basin of......................... 48,268,284,286

lignite beds on................................... 240

navigation of.......................... 57-58,115,127,128
INDKX. 325

Page. 

Sushitna Kiver, structure section at ................ 257

valley of, elimate in.............................. J 45

glacial action in.............................. 247

silted estuary in............................. 281

Suslota formation, age and distribution of...... .. 206,

- 206 (table),222 

Suslota Pass, location of............................ 36,122

Swan River. See Kugruk Kiver. 

Swift Kiver. See Hosiana River. 

Synd, Lieutenant, voyage of........................ 108

Tachat River, location of............................ 63

Tachatna series, age and character of. -.....-..--... 220,236

Tagish Lake, description of............. ------..... 66

Tahkandit series, correlation of..................... 223

Taiya River, description of-..-....,.-..-.---.--..--. 51

Takhin River, location of..............-..--.,--..-.. 50

Takhini River, location of..........--.-.---..-..-..- 67

Taku Inlet, location of.............................. 49

shore topography at, plate showing-............ 18

Taku River, course of, conditions determining...... 286,287

course and character of..................... 49-,~>(), 58,284

drainage basin of......................... 29,48,49-50,58

exploration of...........,....-..-.---.--.---.-.. 49

source of-...,-..-..-..-.......-.-.-..---.------.. 49

valley of, features of........................... 49-50,271

Talkeet Mountains, description of................... 30

southern drainage, of............-..-..--.---.-.. 58

Talkeet River, description of........................ 57

Tanana, climatic records from.-..-.,-.-- 158-17(1,374-175,199 

climatic records from, period covered by........ 138,199

location of....................................... 138,199

Tanana Indians, groups of.......................... 88

intercourse with.......-...._,.._..-..-.-........ 58

Tanana Hirer, description of........................ 82-88

exploration of ....................... 122,125,128-129,205

gneissic areas near............................... 209

valley of, agricultural possibilities of............ 87

lowland area in.............................. 70

structure sections in....... 254 (I'l. XXVII),255,257

topography of...-.,-..-..-..--..-..-.-..-... 79 

Tanana scfiists, ago, character, and distribution

of (table).....................-...-..-..-.--. 206,212,256

Tasnuna River, location of..........,--..-.--.--.... 5(5

Tatlathna River, description of..,..,-..-..-.-...... 63

Tatonduk River, description of..................... 74

Tatslienshini River, description of................... 52-53

Tazlina River, location of........................... 55

Tebenkof, M- IX, explorations by...-.--.--.-..-.... 115

on altitude of Mount St. Elias................... 124

TelograpH Creek, mouth of, altitude of.............. 49

Telegraph lines, construction of.............. 55,118,127,132

routes of-.--.--.---.-----.----.------.--.--.-. 91,118,132

Teller (reindeer station), climatic record from ...... 199

Temperature, extremes of....................... 139,158-161

frequency tables of...................... 179,182,186,1S7

discussion of...................--.--.--.. 178,180-181

observations of, methods of.....-,.-.--..-...... 134-135

Terra Cotta Mountains, location of...,--.--.-....... 34

Terra Cctta scries, correlation of.....,--.-.......... 212

Tertiarj- crustal movements, character of........... 253

Tertiary fossils, occurrence of.-,-.--.--.-.-..-. 206 (table)

236,239,240,242,243 

Tert'ary lavas, occurrence of................ 204,205,241,256

Tertiary plants, occurrence of................... 239,241,242

Tertiary rocks, character and distribution of........ 204,

205,206,206 (table),208,219,235-244,252. 256, 279,280,288

Page. 

Tertiary rocks, stratigraphy of...................... 237-244

Tertiary times, sea invasion during.....-..-..,...-. 273,?92

Teslin, Lake, location of............................ 67,123

Teslin River, description of.......................... 67

Tetling River, description of........................ 83

Thlinkits, habitat and character of............... 20,108,114

Thomson Pass, military trail over................. 30,55, ,56

Three Saints Bay, pioneer settlement at............ 110

Tidal currents, character of......................... 22,26

Tiekel River, location of............................. 56

Tikchik Lake, description of......................... 60

Timber. See Forests.

Times (New York) exploring expedition, account of. 124

Timofeief, Ycrmec, conquests by.................... 105-106

Tisuk Creek, description of.-.--........-----.....-.- 94

Titclna volcanics, a,ge and correlation of......... 206 (table)

Togiak Lake, description of......................... 61

Togiak River, location of----.--.--,--.--.--.-..,..-. 60

Tok River, source and mouth of..................... 84

I Tok sandstone age and correlation of....... 206 (table),241

Tokichitna Kiver, location of........................ 57

Toklat River, description of......................... 86

Tolovana River, description of...................... 86

navigation of.................................... 87

Tonsina River, location of........................... 55

Tonzona River, description of....................... 62

Topham, Edwin, explorations by................... 124

Topliam, W. II., explorations by.................... 124

Topkok Head, topography of shore near............ 24

Topographic map of Alaska-, description of......... 296-298

Topographic maps, enumeration of...-..-.-....,... 130

Topography, character of.......... 11,16,18,23-26,33-36,

52,58,95,100,272-273, 279, 280,283-284, 295, 296 

character of, at shore line, plate showing.... 18,20,22,24

in Fox Kiver Valley, plate showing......... 92

in Mount McKinley region, map showing.... 36

influences determining....... 246,270,290-291,295-296

.nap showing, description of..................... 296-298

plate showing................................ In pocket.

review of......................................... 267-269

types of, classification of........................ 269-286

Tordrillo Mountains, location and altitude of....... 34

Tordrillo series, age and distribution of...... 206 (table), 232

structure of...................................... 257

Totsen scries, age and correlation of.... 206 (table), 215, 218

stratigraphy of.................................. 213

structure of...................................... 259

Townscnd, C. II., explorations 1>y................... 123

Tozi River, description of........................... 88

Trading posts, establishment of..................... 54

Trails. See Routes and trails.

Trangville beds, age a,nd correlation of.......... 206 (table)

Travel. See Routes and trails; Navigation; Railroads. 

Triassic epoch, rolcanism during.................... 265-266

Triassic fossils, occurrence of............ 22(i, 229,231,234, 252

Triassic rocks, deformation of....................... 203

dynamic differentiation of....................... 227

occurrence of............ 203,204, 205,206 (table), 208, 210,

222,223, 225,226, 228, 229,230, 232,234, 250, 257-258 

stratigraphy of.................................. 226-234

Triassic volcanics, occurrence of...........

Trollope, Commander, explorations under. 

Tubutulik River, description of...........

Tuksuk Channel, drainage into............

Tuluga River, location of..................

.... 250 

116

93

94 

.... 102

] Tundra belt,features of................. 47,63,90,92,100,147

Turnagain Arm, location of......................... 21,31

i Turner, J. II., survey by............................ 125
326 INDEX.

Page. 

Turner, J. H., on geography ................... 44,45,76,103

Turner River, description of. ....-.-..-.-.......-.-.- 103

drainage of ...................................... 262

Twelvemile beds, age and distribution of .... 206 (table) , 243

Tyonok, climate at .........--..........-..-..-.----- I*8

climatic records from ................ 142-143, 158-170, 199

period covered by ............................ 138

lignite seams at .....-....-..-.-..............-.-- 240

location of .......-.-..-....-........-..-.-.------ 138

Tyonok beds, age and correlation of ............. 206 (table)

Tyrrell, J. jj.; on geography. ..................... 71,147,246

T7. 

Ugashik, climate at .................................. 150, 151

climatic records from. .... 148 (PL XIX) , 158-170, 172, 199 

period covered by ............................ 138

location of ....................................... 138

Ulrich, E. O., Jurassic fossils identified by .......... 228

Unalaklik River, description of ...................... 92

route to, from Kaltag River......... ............ 91,92

Unalaska, climate at ........................ 133, 145-146, 151

climatic records from. ........................... 142,

143, 148 (PI. XIX), 158-170, 173, 200 

period covered by ............................ 138

coaling station at ................................ 22

location of ....................................... 138

Unga bods, occurrence of .-...--....-..-.....-....-.- 238

Unga Island, climate of ............................. ISO, 151

climatic records from. 158-170, 172, 176, 177-178, 186-188, 190 

periods covered by ........................... 138

coal-bearing rocks of ............................ 240

location of ....................................... 138, 190

Ungalik River, location of ........................... 92

Unimak Island, location of .......................... 22

Unimak Pass, location of ............................ 22

Unuk River, location of ............................. 29, 51

Uplift, cycles of .............................. 280-291, 292-293

diflerential nature of .................... 270. 271, 294, 295

evidences of, in marine benches .................. 296

extent and character of .................. 269-275, 294-295

Upper Colville series, age and correlation of. . . 206 (table) , 244 

Utkiavi, climate at .......................... 148-147. 153, 154

climatic records from ............................ 134,

142-143,148 (PI. XIX), 158-170, 200 

period covered by ............................ 138

location of ....................................... 138

Utukok River, debouchment of ..................... 100

Valdez, climate at ................................... 145

climatic records from ............................ 142-143

See also Fort Liscum. 

military trail from. .............................. 55, 130

telegraphic connections of ....................... 132

Valdez Glacier, route over. .......................... 56, 12g

Valdez series, age and correlation of ............. 206 (table)

stratigraphy of .............................. 228, 229-230

structure of .................................. 232, 255-256

Vallenar series, age and distribution of ...... 206 (table), 226

stratigraphy of .................................. 219

structure of ...................................... 254

Valleys, abandoned. See Streams.

Vancouver, George, coast surveys by ....... 109, 112, 124, 132

Vancouver Island, mountains of .................... 28

Vancouver series, age and distribution of. 206 (table) , 226, 232 

Vasilief , Ensign, explorations by .................... 115

Vegetation. See Forests; Grazing; Moss.

Page. 

Volcanic rocks, mapping of.......................... 205

occurrence of.................... ... 202,206,206 (table),

219,225,232,241,250-251,264,265,266,275 

Volcanism, periods of................ 264,265,275,290,291,295

summary of..................................... 250-251

Volcanoes, location of........... 19,21,22,33,205,250,258,275

Volkmar River, location of.......................... 84

"W.

Wagon roads, construction of.......

Wainwright Inlet, coal horizon at... 

location of.......................

Wales series, age and correlation of.

........... 51

........... 242

.......... 100

........... 206,

206- (table),211,218,219 

structure of...................................... 254

Walker Lake, exploratory trip to................... 123

location and origin of............................ 97,98

War Department, expeditions and surveys by...... 127,130

Waring Mountains, location and altitudes of........ 45,96

Water of Yukon River, analyses of.................. 80-81

sediment in...................................... 79-80

Watercourses, economic importance of.............. 47

Weather Bureau, stations of, location of............ 133-134

stations of, observations at, methods of........ 134-137

See also Meteorologic stations. 

Wellesley, Lake, location of......................... 71

Wellcsley formation, age and correlation of. 206 (table),219 

Wells, S. J., explorations by......................... 125

Western Union Telegraph Company, explorations by 117-

119,132 

weather records kept by......--....--.--.-...... 134

Whaling industry in Arctic Ocean................... 116-117

White Horse, silt terraces at, plate showing........ 250

White Horse Rapids, effect of, on navigation....... 67,68

plate showing.................................... 252

portage around.................................. 122

White Pass, altitude of.............................. 51

White Pass Railway, route of....................... 51,67

White River, basin of, abrupt transition at, plate

showing.........-.--.--..-............ 34

description of.................................... 69-71

exploration of.'.......................... 125-126,128-129

glacial front formerly on........................ 246

gneissoid complex on............................ 209

Whymper, Frederick, exploration by................ 118

Williams, William, exploration by.................. 124

Wingliam Island, location of........................ 21

Witherspoon, D. C., work of................. 13,127,130,298

Wood, C. S. A., explorations by..................... 121

Wood Canyon, description of........................ 56

Wood River, location of............................. 60

Woody Island, climatic records from........ 158-170,172,195

climatic records from, period covered by........ 138

location of........-......................_....... 138

Wrangell, F. P., directorate of-.-..-.-.--.--..-..-.. . 115 

Wrangell lavas, age and distribution of..... 206 (table), 241

Wrangell Mountains, description of................. 31-32

drainage of..................................... 55,83,87

geomorphology of............................... 275

glaciation in..................................... 245

section across.................................... 254,255

snow line in...................................... 245

stratigraphy of.................................. 207

structure of.............................. 230,250,253,256

voleanism in............................. 241,251,290,295

Wrangell Narrows, character of..................... 19

Wright, C. W., on geology................... 208,222,235,239
INDEX. 327

Page. 

W right, C. W., work of ............................. 13,201

Wrigllt, F. K., on geology....................... 208,227,251

work of.......................................... 13,226

Wriglit, F. K., and C. W., acknowledgment to..... 207

on geology....................................... 211

Wullk Elver, location of............................. 100

Yakutat Bay, coastal features of.................... 21,54

exploration of............................... 111-112,124

lignites at........................................ 239

Yakutat series, age and stratigraphic equivalents

of.......................... 227,228,229,232,239

Yanert, William, explorations ]>y................... 128

Yanert Fork, description of--..--------.--.---.----- 80

Yarmouth Inlet, location of......................... 20

Yentna beds, stratigraphie place of................. 240

Yeiitna River, location of........................... 34,57

navigation of.................................... 58,128

York, .shore topography near........................ 24

York Mountains, location of ........................ 39,95

sketch of......................................... 280

York Plateau, geomorphology of.................... 279

location, area, and general features of........... 279-280

shore topograpliy of, plate showing............. 24

sketch of......................................... 280

Young, S. II., explorations by...-...-...-...-....-.. 121

Yukon and White Pass Railway, route of........... 67

Yukon Flats, description of.................. 40,69,74-78,92

origin of.......-...--...--..--...--..--.......-.. 205

plate showing northern margin of, in Chandlar

Valley................................. 42

typical basin lowland of.......-......--....-.-.- 281

Yukon gold fields, route to................... 56,68,69,72,74

Yukon Hills, description of.......................... 88

Yukon peneplain, age of............................. 288

Yukon Plateau, description of............... 276-280,287-288

doming of, at Ramparts......................... 282,295

Page. 

Yukon Plateau, location of .-..-...----.--..---.---- 37

view of..---..--..--..----..--..----.-.-..-------- 267

Yukon poling boat, uses of.-...-----.-----..--..--.. 74

Yukon River, basin of, abandoned valleys in........ 284,285

basin of, ancient stream gravels in.............. 249

erosional interval in _.___...._._ ._.._......_ 265

sea invasion of.............................. 290

course of, conditions determining............... 284

 current velocity of............................... 69,81

delta of.................................... 63,79,92,118

description of............................. 48-49,66,78-92

discharge measurements of...................... 65-66

explorations of.................................. 115,

118,119,120,121,122,125,129,130,132,201,207 

meteorologic stations on ........................ 134

navigation on..................... 64-65,75, 78,92,115,121

tables showing season of.................... 174-175

timber on........................................ 82

valley of, climate of.............................. 11,155

glacial action in.............................. 246

stratigraphy in.............................. 207,208

structure in.................................. 258-259

subprovinces of...-.-.-...-...-.-.-........-. 69

views of...................................... 68,78

volcanic flows in............................. 251

water of, quality of.....--...-.-...-...-......... 79-81

Yukon silts, age and distribution of........ 206 (table),248

Yukon-Tanana region, metamorphic terraces of..... 13

placer fields of................................... ISO

stratigraphy of.................................. 214,215

volcanism in -....--.-.....-...-...-------........ 265

Z.

Zagoskin, L. A., explorations by...........

Zaikof, Potan, expedition of................

Zane, A. V., explorations by...............

Zano Pass, location of......................

91,115

110

123

97
CLASSIFICATION OF THE PUBLICATIONS OF THE UNITED STATES GEOLOGICAL SURVEY.

[Professional Paper No. 45.]

The serial publications of the United States Geological Survey consist of (1) Annual Reports, 

(2) Monographs, (3) Professional Papers, (4) Bulletins, (5) Mineral Resources, (6) Water-Supply 

and Irrigation Papers, (7) Topographic Atlas of the United States folios and separate sheets 

thereof, (8) Geologic Atlas of the United States folios thereof. The classes numbered 2, 7, and 8 

are sold at cost of publication; the others are distributed free. A circular giving complete lists may 

be had on application.

Most of the above publications may be obtained or consulted in the following ways:

1. A limited number are delivered to the Director of the Survey, from whom they may bo 

obtained, free of charge (except classes 2, 7, and 8), on application.

2. A certain number are delivered to Senators and .Representatives in Congress, for distribution.

3. Other copies are deposited with the Superintendent of Documents, Washington, D. C., from 

whom they may be had at practically cost.

4. Copies of all Government publications are furnished to the principal public libraries in the 

large cities throughout the United States, where they may be consulted by those interested.

The Professional Papers, Bulletins, and Water-Supply Papers treat of a variety of subjects, and 

the total number issued is large. They have therefore been classified into the following series: A, 

Economic geology; B, Descriptive geology; C, Systematic geology and paleontology: D, Petrography 

and mineralogy; E, Chemistry and physics; F, Geography; G, Miscellaneous; H, Forestry; I, Irrigation; J, Water storage; K, Pumping water; L, Quality of water; M, General hydrographic investigations; N", Water power; 0, Underground waters; P, Hydrographic progress reports. This paper 

is the seventy-fifth in Series B and the forty-sixth in Series F, the complete lists of which follow. 

(PP=Professional Paper; B = Bulletin; WS=Water-Supply Paper.)

SERIES B, DESCRIPTIVE GEOLOGY.

B 23. Observations on the junction between the Eastern sandstone and the Kuweeuaw series on KPWWTIUW Foil* Lake 

Superior, by R. D. Irving and T. C. Chamberlin. 1885. 124 pp., 17 pis. (Out of stock.)

B 33. Notes on geology of northern California, by J. S. Dillcr. 1886. 23pp. (Out of stock.)

B 39. The upper beaches and deltas of Glacial Lake Agassiz, by Warren Upluim. 1887. 84 pp., 1 pi. (Out of stock.)

B 40. Changes in river courses in Washington Territory due to glaciation, by Bailey Willis. 1887. 10 pp., 4 pis. (Out of 

stock.)

B 45. The present condition of knowledge of the geology of Texas, by R. T. Hill. 1887. 94 pp. (out of stock.)

B 53. The geology of Nantucket, by N. S. Shaler. 1889. 85 pp., 10 pis. (Out of stock.)

B 57. A geological reconnaissance in southwestern Kansas, by Robert Hay. 1890. 49 pp., 2 pis.

B 58. Tlie glacial boundary in western Pennsylvania, Ohio, Kentucky, Indiana, and Illinois, by G. F. Wright, with introduction by T. <:. Chamberlin. 1890. 112 pp., 8 pis. (out of stock.)

B 67. The relations of the traps of the Newark system in the New Jersey region, by N. H. Barton. 1890. 82 pp. (Out of 

stock.)

B 104. Glaciation of the Yellowstone Valley north of the Park, by W. H. Weed. 1893. 41 pp., 4 pis.

BIOS. A geological reconnaissance in central Washington, by I. C. Russell. 1893. 108 pp., 12 pis. (Out of stock.)

B 119. A geological reconnaissance in northwest Wyoming, by (T. II. Eldridge. 1894. 72 pp., 4 pis.

B 137. The geology of the Kori Riley Military Reservation and vicinity, Kansas, by Robert Hay. 1896. 35 pp., 8 pis.

B 144. The moraines of the Missouri Coteau and their attendant deposits, by J. E. Todd. 1896. 71 pp., 21 pis.

B 158. The moraines of southeastern South Dakota and their attendant deposits, by J. B. Todd. 1899. 171 pp., 27 pis.

B 159. The geology of eastern Berkshire County, Massachusetts, by B. K. Emerson. 1899. 139 pp., 9 pis.

B 165. Contributions to the geology of Maine, by H. S. Williams and H. E. Gregory. 1900. 212 pp., 14 pis.

WS 70. Geology and water resources of the Patrick and (ioshen Hole quadrangles in eastern Wyoming and western 

Nebraska, by G. I. Adams. 1902. 50 pp., 11 pis.

B 199. Geology and water resources of the Snake River Plains of Idaho, by I. C. Russell. 1902. 192 pp., 25 pis.

PP 1. Preliminary report on the Ketchikan mining district, Alaska, with an introductory sketch of the geology of southeastern Alaska, by A. H. Brooks. 1902. 120pp., 2 pis.

PI' 2. Reconnaissance of the northwestern portion of Seward Peninsula, Alaska, by A. .1. Collier. 1902. 70 pp., 11 pis.

PP 3. Geology and petrography of Crater Lake National Park, by J. S. Dillcr and H. B. I'atton. 1902. 167 pp., 19 pis.
II SERIES LIST.

PP 10. Reconnaissance from Fort Hamlin to Kotzebue Sound, Alaska, by way of Dall, Kanuti, Alien, and Kowak rivers,

by W. C. Mendenhall. 1902. 68 pp., 10 pis.

PP 11. Clays of the United States cast of the Mississippi River, by Heinrich Ries. 1903. 298 pp., 9 pis. 

PP 12. Geology of the Globe copper district, Arizona, by F. L. Ransome. 1903. 168 pp., 27 pis. 

PP13. Drainage modifications in southeastern Ohio and adjacent parts of West Virginia and Kentucky, by W. G. Tight.

1903. Ill pp., 17 pis. 

B '208. Descriptive geology of Nevada south of the fortieth parallel and adjacent portions of California, by J. E. Kpurr.

1903. 229pp., 8 pis.

B 209. Geology of Ascutney Mountain, Vermont, by R. A. Daly. 1903. 122 pp., 7 pis. 

WS 78. Preliminary report on artesian basins in southwestern Idaho and southeastern Oregon, by I. C. Russell. 1903. 51

pp., 2 pis. 

PP 15. Mineral resources of the Mount Wrangell district, Alaska, by W. C. Mendenhall and F. C. Schrader. 1903. 71 pp.,

10 pis. 

1'P 17. Preliminary report on the geology and water resources of Nebraska west of the one hundred and third meridian,

by N. II. Darton. 1903. 69 pp., 43 pis.

B 217. Notes on the geology of southwestern Idaho and southeastern Oregon, hy I. C. Russell. 1903. 83 pp., 18 pis. 

B 219. The ore deposits of Tonopah, Nevada (preliminary report), by J. K. Spurr. 1903. 31 pp., 1 pi. 

PP20. A reconnaissance ill northern Alaska in 1901, by P. C. Schrader. 1904. 139 pp., 16 pis. 

PP 21. The geology and ore deposits of the Bisbec quadrangle, Arizona, by P. L. Ransome. 1904. 168 pp., 29 pis. 

WS 90. Geology and water resources of part of the lower James River Valley, South Dakota, by J. K. Todd and C. M. Hall,

1904. 47 pp., 23 pis.

PP 25. The copper deposits of the Encampment district, Wyoming, by A. C. Spencer. 1904. 107 pp., 2 pis. 

PP 26. Keonomic resources of the northern Black Hills, by J. D. Irving, with contributions by S. V. Emmons and T. A.

Jaggar, jr. 1904. 222 pp., 20 pis. 

PP 27. Geological reconnaissance across the Bitterroot Range and Clearwater Mountains in Montana and Idaho, by

Waldemar Liudgren. 1904. 122 pp., IB pis. 

PP 31. Preliminary report on the geology of the Arbuckie and Wichita mountains in Indian Territory and Oklahoma, by

J. A. Taff, with an appendix on reported ore deposits in the Wichita Mountains, by H. F. Bain. 1904. 97pp., 8 pis. 

B 235. A geological reconnaissance across the Cascade Range near tlie forty-ninth parallel, by G. O. Smith and F. C. Calkins.

1904. 103pp., 4 pis.

B 236. The Porcupine placer district, Alaska, by C. \V. Wright. 1904. 35 pp., 10 pis. 

B 237. Igneous rocks of the Highwood Mountains, Montana, by L. V. Pirsson. 1904. 208 pp., 7 pis. 

B 238. Economic geology of the lola quadrangle, Kansas, by G. I. Adams, Erasmus Haworth, and W. R. Crane. 1904. 83

pp., 1 pi.

PP 32. Geology and underground water resources of the central Great Plains, by N. H. Darton. 1905. 433 pp., 72 pis. 

WS 110. Contributions to hydrology of eastern United States, 1904; M. G. Fuller, geologist in charge. 1905. 211 pp., 5 pis. 

B 242. Geology of the Hudson Valley between the Hoosie and the Kinderhook, by T. Nelson Dale. 1904. 63 pp., 3 pis. 

PP 34. The Dclavan lobe of the Lake Michigan Glacier of the Wisconsin stage of glaciation and associated phenomena, by

\V. C. Alden. 1904. 106 pp., ]5 pis.

PP 35. Geology of the Perry Basin in southeastern Maine, by G. O. Smith and David White. 1905. 107 pp., 6 pis. 

B 243. Cement materials and industry of the United States, by E. C. Eekel. 1905. 395 pp., 15 pis. 

B 246. Zinc and lead deposits oi noi iueasierr. Illinois, by H. P. Bain. 1904. 56 pp., 5 pis. 

B 247. The Fairhaven gold placers of Seivard Peninsula, Alaska, by F. H. Moffit. 1905. 85 pp., 14 pis. 

B 249. Limestones of southwestern Pennsylvania, by F. G. Clapp. 1905. 52pp., 7 pis. 

B 250. The petroleum fields of the Pacific coast of Alaska, with an account of the Bering River coal deposit, by G. C. Martin.

1905. 65pp., 7 pis.

B 251. The gold placers of the Fortymile, Birch Creek, and Fairbanks regions, Alaska, by L. M. Prindle. 1005. 89 pp., 16 pis. 

WS. 118. Geology and water resources of a portion of east-central Washington, by F. C. Calkins. 1905. 96 pp., 1 pis. 

B 252. Preliminary report on the geology and water resources of central Oregon, by I. C. Russell. 1905. 138 pp., 24 pis. 

PPS6. The lead, zinc, and fluorspar deposits of western Kentucky, by E. O.Ulrich and W. S. Tangier Smith. 1905. 218pp.,

15 pis. 

PP 38. Economic geology of the Bingham mining district of Utah, by J. M. Boutwell, with a chapter on areal geology, by

Arthur Keith, and an introduction on general geology, by S. F. Emmons. 1905. 413 pp., 49 pis. 

PP 41. The geology of the central Copper River region, Alaska, by W. C. Mendenhall. 1905. 

B 254. Report of progress in the geological resurvey of the Cripple Creek district, Colorado, by Waldemar Lindgren and

F. L. Ransome. 1904. 36 pp.

B 255. The fluorspar deposits of southern Illinois, by H. Foster Bain. 1905. 75 pp., 6 pis. 

B 256. Mineral resources of the Elders Ridge quadrangle, Pennsylvania, by R. W. Stone. 1905. 85 pp., 12 pis. 

B 257. Geology and paleontology of the Judith River beds, by T. W. Stanton and J. B. Hatcher, with a chapter on the

fossil plants, by F. H. Knowlton. 1905. 174 pp., 19 pis.

PP 42. Geology of the Tonopah mining district, Nevada, by J. E. Spurr. 1905. 295 pp., 24 pis. 

WS 123. Geology and underground water conditions of the Jornada del Muerto, Ne\v Mexico, by C. R. Keyes. 1905.

42pp., 9 pis.

WS 136. Underground waters of Salt River Valley, Arizona, by W. T. Leo. 1905. 196 pp., 24 pis. 

PP 43. The copper deposits of the Clifton-Morenei district, Arizona, by Waldemar Lindgren. ]905. 372 pp., 25 pis. 

B 265. Geology of the Boulder district, Colorado, by N. M. Fenneman. 1905. 101 pp., 5 pis. 

B 267. The copper deposits of Missouri, by H. Foster Bain and E. O. Ulrich. 1905. 52 pp., 1 pi. 

PP 'A. Underground water resources of Long Island, New York, by A. C. Veateh, C. S. Slichtcr, Isaiah Bowman, W. O.

Crosby, and R. E. Horton. 1906. 394 pp., 34 pis.
SERIES LIST. Ill

WS 148. Geology and water resources of Oklahoma, by 0. N. Gould. 1905. 178 pp., 22 pis. 

B 270. The configuration of the rock floor of Greater New York, by W. H. Hobbs. 1905. 96 pp., 5 pis. 

B 272. Taconic physiography, by T. N. Dale. 1905. 52 pp., 14 pis.

PP 45. The geography and geology of Alaska, a .summary of existing knowledge, by A. H. Brooks, with a section on climate, 

by Cleveland Abbe, jr., and a topographic map and description thereof, by R. U. Goode. 1906. 327 pp., 34 pis.

SERIES F, GEOGRAPHY.

B 5. Dictionary of altitudes in United States, by Henry Gannett. 1884. 325 pp. (Out of stock; see Bulletin 274.)

B 6. Elevations in Dominion of Canada, by J. W. Spencer. 1884. 43pp. (Out of stock.)

B 13. Boundaries of United States and of the several States and Territories, with historical sketch of territorial changes, 

by Henry Gannett. 1885. 135pp. (Out of stock; see Bulletin 226.)

B 48. On form and position of sea level, by E. S. Woodward. 1888. 88pp. (Out of stock.)

B 49. Latitudes and longitudes of certain points in Missouri, Kansas, and New Mexico, by R. S. Woodward. 1889. 133pp.

B 50. Formulas and tables to facilitate the construction and use of maps, by R.S. Woodward. 1889. 124pp. (Out of stock.)

B 70. Report on astronomical work of 1889 and 1890, by R. S. Woodward. 1890. 79 pp.

B 72. Altitudes between Lake Superior and Rocky Mountains, by Warren TJpham. 1891. 229 pp.

B 76. Dictionary of altitudes in United States (second edition), by Henry Garnett. 1891. 393 pp. (Out of stock; see 

Bulletin 274.)

B 115. Geographic dictionary of Rhode Island, by Henry Gannett. 1894. 31 pp.

B 116. Geographic dictionary of Massachusetts, by Henry Gannett. 1894. 126 pp.

B 117. Geographic dictionary of Connecticut, by Henry Gannett. 1894. 67 pp.

B 118. Geographic dictionary of New Jersey, by Henry Gannett. 1894. 131 pp.

B 122. Results of primary triangulatiou, by Henry Gannett. 1894. 412pp., 17 pis. (Out of stock.)

B 123. Dictionary of geographic positions, by Henry Gannett. 1895. 183 pp., 1 map. (Out of stock.)

B 154. Gazetteer of Kansas, by Henry Gannett. 1898. 246 pp., 6 pis.

B 160. Dictionary of altitudes in United States (third edition), by Henry Gannett. 1899. 775pp. (Out of stock: see Bulletin 274.)

B 166. Gazetteer of Utah, by Henry Gannett. 1900. 43 pp., 1 map.

B 169. Altitudes in Alaska, by Henry Gannett. 1900. 13 pp.

B 170. Survey of boundary line between Idaho and Montana from international boundary to crest of Bitterroot Mountains, 

by R. U. Goode. 1900. 67 pp., 14 pis.

B 171. Boundaries of United States and of the several States and Territories, with outline of history of all important changes 

of territory (second edition), by Henry Gannett. 1900. 142 pp., 53 pis. (Out of stock; see Bulletin 226.)

B 174. Survey of northwestern boundary of United States, 1857-1861, by Marcus Baker. 1900. 78 pp., 1 pi.

B 175. Triangulation and spirit leveling in Indian Territory by C. H. Fitch. 1900. 141 pp., 1 pi.

B 181. Results of primary triangulation and primary traverse, fiscal year 1900-1901, by H. M. Wilson, J. H. Rensliavre, 

E. M. Douglas, and R. U. Goode. 1901. 2^0 pp., 1 map.

B 183. Gazetteer of Porto Rico, by Henry Gannett. 1901. 51 pp.

B 185. Results of spirit leveling, fiscal year 1900-1901, by H. M. Wilson, J. H. Renshawe, E. M. Douglas, and R. U. Goode. 

1901. 219 pp.

B187. Geographic dictionary of Alaska, by Marcus Baker. 1901. 446pp. (Out of stock.)

B 190. Gazetteer of Texas, by Henry Gannett. 1902. 162pp., 8 pis. (Out of stock; see Bulletin 224.)

B 192. Gazetteer of Cuba, by Henry Gannett. 1902. 113 pp., 8 pis. (Out of stock.)

B 194. Northwest boundary of Texas, by Marcus Baker. 1902. 51 pp., 1 pi.

B196. Topographic development of the Klamath Mountains, by J. S. Diller. 1902. 69 pp., 13 pis.

B 197. The origin of certain place names in the United States, by Henry Gannett. 1902. 280pp. (Out of stock.)

B 201. Results of primary triangulation and primary traverse, fiscal year 1901-2, by H. M.Wilson, J. H. Renshawe, E. M. 

Douglas, and R. U. Goode. 1902. 164 pp., 1 pi.

B 214. Geographic tables and formulas, compiled by S. S. Gannett. 1903. 284 pp.

B 216. Results of primary triangulation and primary traverse, fiscal year 1902-3, by S. S. Gannett. 1902. 222 pp., 1 pi.

B 224. Gazetteer of Texas (second edition), by Henry Gannett. 1904. 177 pp., 7 ply.

B 226. Boundaries of the United States and of the several States and Territories, with an outline of the history of all important changes of territory (third edition), by Henry Gannett. 1904, 145 pp., 54 pis.

B 230. Gazetteer of Delaware, by Henry Gannett. 1904. 15 pp.

B 231. Gazetteer of Maryland, by Henry Gannett. 1904. 84 pp.

B 232. Gazetteer of Virginia, by Henry Gannett. 1904. 159 pp.

B 233. Gazetteer of West Virginia, by Henry Gannett. 1904. 164 pp.

B 234. Geographic tables and formulas (second edition), compiled by S. S. Ganrett. 1904. 310 pp.

B 246. Results of primary triangulation and primary traverse, fiscal year 1902-3, by S. S. Gannett. 1904. 328 pp., 1 pi.

B 248. Gazetteer of Indian Territory, by Henry Gannett. 1904. 70 pp.

B 258. The origin of certain place names in the United States (second edition), by Henry Gannett. 1905. 334 pp.

PP46. The geography and geology of Alaska, a summary of existing knowledge, by A. H. Brooks, with a section on climate,

by Cleveland Abbe, jr., and a topographic map and description thereof, by R. U. Goode. 1906. 327 pp., 34 pis. 

Correspondence should be addressed to

THE DIRECTOR,

UNITED STATES GEOLOGICAL SURVEY,

WASHINGTON, D. C. 

MARCH, 1906.

17211 No. 45 06 22 O
U.S. GEOLOGICAL SURVEY PROFESSIONAL PAPER NO. 45 PL. XXXIV

MAP OF

lalkettC.

1 farrison 

Bay ALASKA

Compiled under the direction of R.U.Goode, Geographer,

by E. C. Barnard and others.

19O3

Scale 2.500,000 

Approximately 40 miles to 1 inch.

120

Coivtour interval 1000 feet.

Datum is mean sea- leveL.

1904

Note:5%c shaded areas in,&i£ above diagrttfnare those which, have been- mapped fy> tfi& 

Geological Survey and on wfdcft, the, map of A lajsJui- wittutv tfie coast line is principally baaed,. 

The mops of Gte, Cocuft and Geodetic Survey in southeastern, Alaska, and along the coast 

hare&een extensively utilized. Other sources of information have, Iteen, from, the maps 

ofthe'Anny, the Navy, the Revenue-Marine,,Service and, (ht British Government. Large 

areas of Alaska,, cover-ing by far the greater portion of the map have not been surveyed., 

and the topographic, features .ihown in. these, localities are based, upon such general 

o))A _ -

infbrmaiion, n.v ttonM.

\J f i / / _ -^

n r-n^A ^»

SKA

GULF

' /rMarmotT

176 East of Greenwich 178 178 West of Greenwich.

152 West of GreexrwiclL 150