DEPARTMENT OF THE INTERIOR

BULLETIN

OF THE

UNITED STATES

GEOLOGICAL SURVEY

No. 158

WASHINGTON

GOVERNMENT PRINTING OFFICE

1899

UNITED STATES GEOLOGICAL SUEVET

CHARLES D. WALCOTT, DIRECTOR

THE

THEIR ATTENDANT DEPOSITS

BY

JAMES EDWARD TODD

WASHINGTON

GOVERNMENT PRINTING OFFICE 

1899

CONTENTS.

CHAPTER I. INTRODUCTION ................................................ 13

History of work........................................................ 13

Limits of region ........................................................ 14

Sketch of older formations.............................................. 14

Elevations............................................................... 16

Acknowledgments ...................................................... 16

CHAPTER II. FIRST (OUTER) OR ALTAMONT MORAINE ....................... 18

Course of the moraine................................................... 18

From Turtle Point to Pratt Creek ................................... 19

From Pratt Creek to Eunning Water ................................ 25

Emanuel Creek Gap................................................. 28

From Bonhomme to Spirit Mound ................................... 29

Turkey Eidge................................................... 31

Vermilion Gap ...................................................... 32

From Brule Creek to Canton ........................................ 32

Big Sioux Gap ...................................................... 34

From the Big Sioux to Vermilion Point.............................. 35

General characteristics of the moraine................... ................ 36

Structure and position ...... ........................................ 37

Height .............................................................. 38

Stoniness and distribution of bowlders .............................. 39

CHAPTER III. THE DRIFT REGION OUTSIDE OF THE OUTER MORAINE........ 42

Bed Lake region ........................................................ 42.

Ancient channels ................................................... 46

Bowlder ridges ..................................................... 47

Old water line ...................................................... 47

Elevations ........................................................... 48

Notes from wells and other exposures................................ 49

Explanatory hypotheses ............................................ 51

Ponca reach, or region from mouth of Pratt Creek to mouth of Niobrara.. 53

Loess region ............................................................. 56

Boundaries and surface.............................................. 56

Western boundary of glacial drift............................... 56

Eastern boundary of glacial drift................................ 58

Description of surface .......................................... 58

Elevation................................................... 58

Basins and knolls.................'.......................... 60

Elevated ridges............................................. 60

Ancient channels.............................................. 60

Areas sloping away from principal streams .................. 61

Principal streams................. .......................... 62

Terraces.................................................... 63

Sandhills .................................................. 64

5
CONTENTS.

CHAPTER III. THE DRIFT REGION OUTSIDE OF THE OUTER MORAINE Cont. 

Loess region Continued.

Drift deposits of the loess region..................................... 64

Till, its color, structure, etc..................................... 65

Ked clay..-...--................................................ 66

Gravel and sand depo'sits........................................ 66

Relation of the drift to the underlying formations ..............'. 67

Striation of underlying rocks........... ......................._. 68

Distribution of the drift ........................................ 69

In Nebraska .......................................... '...... 69

Volcanic ash stratum ................................... 70

In South Dakota............................................ 81

In Iowa ...................... ...... . ;.... ............ .....'. 85

Elevation of surface of drift of loess region..:....;........'...... 91

Eolations of drift to loess ............"........................... 93

The " old soil" and the charcoal streak..1....................... 93

Summary ..............................___"___...........:....... 94

Loess............................................................... 95

Structure and composition ...................................... 95

Extent. .................................. ...................... 96

Fossils.............................. .......'.-..:....I........... 98

Concretions............................... ...................... 98

Origin.......................................................... 99

Thickness .............................................. I....... 99

Relation to the outer moraine ............V...................... 100

Coteau des Prairies region ......................................... '. ..,.. 103

Boundaries..................................................:.. 103

Surface................................................. ........ 103

Valleys............................ ............................. 104

The Dells at Dell Rapids.-........-.....---..--....-..-..-...... 107

Great Bend of the Big Sioux .................................... 108

Bowldery knolls ............................ 1. .................. 109

Hummocks ....... ................ .... .......... ................. 110

Strisz........................................................... 110

CHAPTER IV. THE DRIFT REGION INSIDE OF THE OUTER MORAINE ............ 113

Second or Gary moraine. ..............................- -. - H3

Region between the second and principal moraines ...................... 117

General characteristics.......... ...... .............................. 117

Western region ................................... 1................. 117

Ancient lakes................................................... 119

Ancient channels................................................ 119

Wells........................................................... 120

An ancient tamarack swamp ............'...'..'.".....'.'.'........... 121

Spotted surface of the country .................................. 121

James Valley ....................................................... 122

Exposures of older rocks........................................ 122

Vermilion Valley ......................1............................ 123

Region inside the second moraine....................................... 124

Flowing wells .......... ^....................................... 125

Cause of Lake Dakota.......................................... 125

Buried wood.... ....................~............................ 126

Striae within the moraine....................................... 126
CONTENTS. 7

Page.

CHAPTER V. TERRACES OF THE MISSOURI AND BIG Sioux, AND HYDROLOGY

OF THE REGION ....................................................... 128

Terraces of the Missouri and its tributaries............................. 128

Silt terraces ......................................................... 128

Lower bowldery terraces............................................ 130

Composition .............. ....... .............. .............. .... 133

Higher bowldery terraces........................................... 135

Terraces along the Big Sioux........................................... 138

Silt and lower bowldery terraces.................................... 138

Higher bowldery terraces........................................... 139

Terraces along other streams............................................ 140

Present slopes of the Missouri and Big Sioux............................ 140

Age of the terraces..................................................... 140

Diagram of the trough of the Missouri.................................. 141

Westward elevation of the region. ........................ .............. 141

Northward elevation of the region...................................... 144

Age of the trough of the Missouri....................................... 146

Is the trough of pre-Glacial origin?................................. 146

The trough still deepening .......................................... 150

Was the trough excavated previous to the loess epoch ?.............. 153

Elevations.............................................................. 154

INDEX ...................................................................... 169

ILLUSTRATIONS.

PLATE I. Pleistocene deposits of southeastern South Dakota and adjacent

regions......................................................... 14

II. View of Turtle Ridge from the east............ .................... 20

III. View of old overflow channel in Turtle Ridge ..................... 22

IV. Lake Andes Outlet, from the north................................ 26

V. James Ridge, from the north ...................................... 28

VI. The attenuated moraine and Spirit Mound......................... 30

VII. Mapof Turkey Ridge............................................. 32

VIII. Details of the moraine in Union County........................... 34

I.. Chaunel, lake, and osar ridges northeast of Montrose.............. 36

X. Continuation of osars east of Montrose............................ 38

XI. Near view of volcanic ash stratum in bluff above West Point,

Nebraska....................................................... 70

XII. Bluff ab.ove Florence, Nebraska, showing ash stratum............. 72

XIII. Base of drift near Coleridge, Nebraska............................. 74

XIV. Eastward view from north edge of the loess south of Herrick,

Nebraska....................................................... 102

XV. Ice sheet occupying the principal moraine......................... 120

XVI. Ice sheet occupying the second moraine ........................... 122

XVII. Photograph of striae on the quartzite near Bridgewater, South

Dakota......................................................... 126

XVIII. Great bend of the Missouri, from the east ......................... 128

XIX. Lower bowldery terrace opposite Fort Randall .................... 132

XX. Lower bowldery terrace, from the old bank north of Greenwood,

South Dakota................................................... 134

XXI. Upper bowldery terrace southwest of Santee Agency, Nebraska .... 136

XXII. Big Sioux River near Fairview, South Dakota ..................... 138

XXIII. Diagram of main features of the trough of the Missouri........... 140

XXIV. Sections across the glaciated region east and west................. 144

XXV. Sections radiating across the moraines............................. 146

XXVI. Sections across the Missouri at Chamberlain, Sioux City, and Blair.. 148 

XXVII. Sections across the Missouri at Omaha, Plattsrnouth, and Nebraska

City............................................................ 150

FIG. 1. Turtle Point, from the northwest ................................... 19

2. Map of Turtle Ridge and southwest Wessingtons.................... 20

3. Transverse section of Turtle Ridge.................................. 21

4. Map of osar-like ridges near Crow Lake............................. 23

5. Portion of the moraine near Bijou Hills............................. 24

6. Cedar Creek Hills, from the north .................................. 25

7. The moraine half eroded by the Missouri............................ 26

8. General view of the moraine from 2 miles south of Grandview....... 27

9. James Ridge, from the west......................................... 30

10. Inner slope of the moraine south of Wall Lake....'................. 35

11. Section of southwest Wessingtons .................................. 37

9
10 ILLUSTRATIONS.

FIG. 12. Bijou Hills, from the north.. ........................................

13. Buttes south of White River, from the north .........................

14. Exposure showing base of the till north of Pacific Junction, Iowa.. .

15. Exposure showing base of the till near Berks, Nebraska. . ...........

16. Section of south bluff of Missouri River near Herrick, Nebraska ....

17. First railroad cut east of Osmond, Nebraska ... 1 .................... 7&

18. Cuts east of Osmond, Nebraska. .................................... 76

19. Sandpit section east of McCook, South Dakota ...................... 86

20. Summit cut between Silver and Keg creeks '. .......................... 94

21. Cut on Omaha and St. Louis Railroad west of Walnut Creek, Mills

County, Iowa .................................................... 94.

22. Section from Boonsboro, Iowa, to the Missouri.... ......... '.1. ... ..".'." 101

23. Section near south line of Carroll County, Iowa. . . .................. 101

24. Section near junction of Middle Raccoon River and Willow Creek, .

Iowa............................................................. 102"

25. Sections at Sioux Falls, South Dakota ............................'.. 102

26. Sections at Sioux Falls, South Dakota .............................. 103

27. Various markings on Sioux quartzite.... ........................... Ill

28. Pony Hills near Woonsocket, South Dakota ......................... 114

29. Enemy Creek Hills, from the northeast. ............................. 115

30. A "gouge" from quartzite exposure near Bridgewater, South Dakota. . 126-

31. Record of s'oundings at Blair bridge, 1883. .......................... 151
LETTER OF TRANSMITTAL.

DEPARTMENT OF THE INTERIOR,

UNITED STATES GEOLOGICAL SURVEY,

Chicago, III, August 22,1898.

SIR : I have the honor to submit herewith a report by Prof. James 

E. Todd on The Moraines of Southeastern South Dakota and their 

Attendant Deposits, which will be found to contain a large amount of 

valuable data relating to the later formations of that State. 

Very respectfully, yours,

T. C. CHAMBERLIN,

Geologist. 

Hon. CHARLES D. WALOOTT,

Director of the United States Geological Survey.

11

THE MORAINES OF SOUTHEASTERN SOUTH DAKOTA 

AND THEIR ATTENDANT DEPOSITS.

By J. E. TODD

CHAPTER I. 

INTRODUCTION.

HISTORY OF WORK.

At the reorganization of the United States Geological Survey in 

1881, the author, under the direction of Prof. T. C. Chamberlin, geologist in charge of the glacial division, was instructed to explore the 

Dakota loop of the great moraine. At that time very little was known 

of the distribution of drift in Dakota. Aside from certain theoretical 

considerations which had been expressed by Professor Chamberlin and 

Mr. Warren Upham, little had been presented upon the subject. A few 

topographical notes by Nicollet in 1842, and a more direct treatment of 

the subject from wide but incomplete observation, presented by Gen. 

G. K. Warren in 1868 before the Chicago meeting of the American 

Association for the Advancement of Science, were the more important 

statements of observation. The latter distinctly makes the limit of 

glacial action to coincide with the Missouri River from the forty-eighth 

to the forty-third parallel. Dr. F. Y. Haydeu also, in the American 

Journal of Science for January, 1867, published a very interesting 

account of a trip taken by him to Rockport, Dakota, and Pipestone, 

Minnesota, in the previous October. His notes refer mainly to the 

older formations, but incidentally he records features of the drift.

After an examination of the field during the summers of 1881, 1882, 

and 1883 it was considered better to delay a report upon the whole 

region, and to present a preliminary report in the form of a bulletin 

upon a limited portion. The portion chosen, and to which this bulletin 

relates, was thought to bear most directly upon certain important questions and to be likely to furnish the most important results; moreover, 

it was the most accessible portion, because more generally occupied by 

settlers.

13
14 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

LIMITS OF REGION.

The limits chosen in the regular course of the moraine the axial 

limits are Turtle Point in Jerauld County, and a corresponding point 

in the northwestern part of Lake County. For convenience in reference we will name the latter Vermilion Point. Turtle Point is a conspicuous landmark, which forms a natural point of division on the west 

side of the loop, while Yermilion Point is on the east side of the loop 

in about the same latitude, and, although it is not so prominent a point 

of division,; it is the most marked point near the northern limit of the 

writer's acquaintance with the moraine upon the east side. Turtle 

Point is upon the eastern edge of what is commonly known as the 

Coteau du Missouri, a region between the James and Missouri rivers 

spoken of by the early French explorers as the Plateau du Coteau du 

Missouri. The term " plateau," however, is a misnomer, for instead of 

a continuous plateau, it is merely the skeleton of one. The peripheral 

limits are, briefly, as follows: On the north, the parallel of Turtle Point, 

which is arbitrarily taken. On the other sides the limit theoretically 

coincides with that of the extreme dispersion of erratics from the portion of the moraine under consideration. On the west this boundary 

is most definite and is near; on the east it is confused with that of the 

.Iowa lobe; on the south the theoretical limit is so remote that we shall 

need to fix an arbitrary limit, which we will take as not more than 100 

milet.,from the moraine. A map of the region under consideration is 

shown on PI. I.

Some of the advantages which may be derived from a careful presentation of this porti6n of the moraine are the following:

First. It gives opportunity to present in a natural and consecutive 

manner several typical features of drift deposits, moraines, berg drift, 

drainage outlets, gravel terraces, qsars, etc.

Second. It furnishes important data upon several of the open questions connected with certain Pleistocene problems, viz: The origin of 

loess, the distribution of glacial and glacio-natant deposits, oscillations 

of the earth's crust in the post-Pliocene, besides several minor questions 

. connected with the physics and history of the. glaciers.

Third. It forms a convenient introduction to the larger subject which 

it was first proposed to present.

SKETCH OF OLDER FORMATIONS.

Though our work pertains especially to the recent deposits formed 

during the Pleistocene period, a brief consideration of older deposits 

seems important, for the underlying rocks have influenced in several 

ways the distribution of the drift.

The older formations belong to widely separated epochs. So far as is 

yet known, the region under consideration exhibits only strata belonging to the Algonkian and the Cretaceous, with scattered fragments of
U.S.GEOLOGICAL SURVEY BULLETIN NO. 158 PL. I

t_ >rf""l/n^ V S r j. ia 

^SV. ^.VoWitflorito, ,.4 -.. -- ?£»»*. 'fT$&,. Trlrf?* «.«*('!;

PLEISTOCENE DEPOSITS OF SOUTHEASTERN DAKOTA AND ADJACENT REGIONS

BY J.E.TODD.I898

TERRACES AND OLD CHANNELS. "^C^WOSAR RID6ES. - LIMIT OF NORTHERN OR GLACIAL DRIFT.

Note : Numbers on this map denote 

comparative a£e of moraines
.TODD.] ' .".' OLDER FORMATIONS. . \ 15

.Tertiary deposits. The Algonkian or, as it has been considered by 

Prof. 1ST. H. Winchell, the lower Cambrian is represented only by the 

red quartzite, .which is conspicuously exposed along the Big Sioux, and 

was named several years since by Dr. C. A. White the Sioux quartzite. 

The exposures in this region appear to be portions of an irregular syncline, extending from southwestern Minnesota to the James Eiver. An 

enumeration of localities will be found on another page (p. 122). The 

strata have usually but slight dip, rarely more than 6°. Eipple marks are 

frequent, but no fossils, except a few .of doubtful character, have yet been 

found.1 The rock bears evidence of ebb-and-flow structure. Oblique 

stratification, inclining in; different directions, abounds in some strata. 

Thin seams of metamorphosed clay occur occasionally, the more notable 

being the "pipestone," at Pipestone, Minnesota. The lower stratum 

exposed on Wolf Creek is a bed of uhconsolidated sand, evidently once 

consolidated but now decomposed. ..

- The Cretaceous rocks all belong to the Dakota group and to the 

three members separated by Hayden, but combined by King into the 

Colorado group.

The first, the Dakota sandstone, is exposed along the James River 

and its tributaries in Hutchinson, Hanson, and Davison counties and 

along the Missouri below Ponca, Nebraska. .

The Benton group, comprising dark pyritiferous clays, is certainly 

found exposed only along the bluffs of the Missouri, from near the 

mouth of the James Eiver to the vicinity of the Big.Sioux.2 Slight 

exposures near Milford, Nebraska, and Eockport, Dakota, also possibly belong to this group.

The Niobrara of Hayden, the chalkstone, forms a more conspicuous 

and important deposit, which extends very widely under the drift. It 

is exposed along the Missouri from Chamberlain to Sfc. Helena; along 

the James and its tributaries in Hanson and Davison counties; at several localities along Clay and Turkey creeks; upon Beaver Creek, near 

Canton; on the Split Eock, north of Brandon; along the Big Sioux, at 

Akron and below, comprising the Inoceramus beds of White, and along 

Brule Creek, in Union County. : .

The Pierre group, consisting of clays of different colors and qualities, probably occupies four-fifths of the surface underneath the drift. 

It is exposed along the Missouri from near the mouth of the Niobrara to 

the northern limits of the region. It is this formation which is struck 

in wells which pass through the drift in all localities in the Dakotas east 

of the Missouri, except those that have been already indicated.

The Tertiary rocks are represented by the greenish quartzite well 

shown at the Bijou Hills and various beds of sand, gravel, and clay 

that are associated with it. These are ascribed, to the Loup Eiver 

'group by Dr. Hayden, and no reason for questioning the determination

1 Prof. 'N. H. Winchell, Thirteenth Ann. Kept. Geol. Nat. Hist. Survey Minnesota, 1884. 

2 Cf. Hayden, 1870, p. 87. .
16 MORAINES OF SOUTHEASTERN SOUTH DAKOTA [BULL. 158.

has come to the writer's knowledge. 1 Distinct fossils were not noticed 

by him in it, though pieces of petrified wood and of mammalian 

bones have been noticed upon it, which may have been derived from 

it. It contains greenish pebbles of pitchstone at many points. In 

northeastern Nebraska the Loup River Tertiary is represented by over 

-80 feet of sands, marls, and clays containing petrified shells and bones 

of animals. From similarly situated beds north of Sioux City teeth of 

Equus major have been reported by Mr. Bain, who referred the beds 

to the Pleistocene.2

The Cretaceous clays have contributed largely to the mass of the 

till. The Tertiary rocks have been influential in the formation of buttes 

which have had an important limiting and directing influence upon the 

ice sheet. The Archean rocks have been less influential, not having 

been prominent enough to limit or deflect the ice, nor sufficiently 

yielding to contribute material of much volume. In a few cases, as at 

Eockport and near Alexandria, they seem to have exercised considerable directing power upon the lower portion of the ice.

ELEVATIONS.

The elevations which form an important portion of this paper were 

mostly taken with an aneroid barometer. A few are derived directly 

from railroad profiles. The more important elevations have been taken 

either several times or on days when the barometer showed little 

fluctuation. In general their accuracy corresponds to their distance 

from important streams or from railroads. A few are taken from the 

topographic surveys of the United States Geological Survey. At the 

beginning of our work the number of railroad elevations in the region 

under consideration was quite small, on account of its recent settlement. But the rapid railroad building of the last few years has been 

favorable to the work, both by furnishing exposures and in affording 

fresh and accurate information concerning elevations. The accuracy 

of the survey has been materially aided through the generous response 

on the part of railroad engineers to requests for profiles. In the 

appendix several of these are published for the first time.

, ACKNOWLEDGMENTS.

I would hereby gratefully acknowledge my indebtedness to Mr. D. J. 

Whittemore, chief engineer of the Chicago, Milwaukee, and St. Paul 

Eailway Company, for a carefully prepared list of elevations of all 

stations and bridges over important streams along its lines in the 

States of North and South Dakota; to Mr. E. Gerber,assistant engineer 

of the Fremont, Elkhorn and Missouri Valley Eailroad Company, for 

elevations upon all its lines in Nebraska, a section of the Missouri 

Eiver at Blair, and other favors; to Mr. C. W. Johnson, chief engineer

1 Gen. G-. K. Warren's preliminary report on Nebraska and Dakota, p. 78. 

'Iowa Geol. Survey, Vol. V, p. 277.
TODD.] ACKNOWLEDGMENTS. 17

of the Chicago, St. Paul, Minneapolis and Omaha Eailway Company, 

for elevations of all stations on its lines in* Nebraska, and a section of 

the Missouri at Sioux City; to Mr. B. B. Colborne for a profile of a 

preliminary survey from Chamberlain, Dakota, to Lemars, Iowa; to 

Mr. George A. Lederle for a section of the Missouri at Omaha; and 

to Mr. J. H. Charles, of Sioux City, for obtaining elevations on the 

Sioux City and Northern Eailway and the Pacific Short Line. I would 

also express gratitude to Hon. Alexander Mitchell, of the Chicago, Milwaukee and St. Paul Eailway Company, and to Hon. Marvin Hughitt, 

general manager of the Chicago and Northwestern Eailway Company, 

for favors shown in transportation. 

Bull. 158 2
CHAPTEE II. 

FIRST (OUTER) OR ALTAMONT MORAINE.

This is first presented because it furnishes a convenient line of reference in the further treatment of the area under consideration. It is 

also the best denned and most constant feature.

I COURSE OF THE MORAINE.

The accompanying map, PI. I, with a brief explanation, will give a 

comprehensive view of the direction and divisions of the moraine.

Beginning at Turtle Point, in Jerauld County, the? head of a prominent interlobular portion, the moraine extends in a south and southwest direction past the Bijou Hills, nearly to the junction of Pratt 

Creek with the Missouri, where there is a gap a few miles in breadth. 

The more notable variation from a direct course is a small loop pushed 

westward toward Bed Lake.

East of Pratt Creek the moraine appears again in the Cedar Creek 

Hills, which, lying on both sides of Cedar Creek, form a high V-shaped 

reentrant angle, pointing northeast. From the eastern end of the V 

the moraine extends in a general southeasterly direction, nearly to the 

junction of Wet Choteau and Dry Choteau creeks, where it crosses 

the former, turns sharply northward, and forms a long interlobular 

portion around the latter stream, being known as the Choteau Creek 

Hills. Below the junction of the Choteaus the moraine lies along the 

west bank of the stream nearly to its mouth, where it crosses and continues close along the bluffs of the Missouri to a point opposite the 

mouth of the Niobrara, whereat develops a slight reentrant angle.

From this point no trace of it is found on either side of the Missouri 

until we pass below Bonhomme. A little east of that place, on the 

north side of the Missouri, it appears again, and, after forming a, long 

and much-eroded loop to the east, reaches Lesterville, where, after 

forming a much smaller similar loop, it takes a southeasterly direction. 

About 6 miles east of Yankton it swings more to the east, crosses the 

James Eiver, and continues to a broad gap through which Clay Creek 

passes. East of the Clay Creek Gap it reappears along the east bank 

of that stream and runs north and northwest to the vicinity of Childstown, where it again doubles upon itself and takes a quite direct course 

southeast to Spirit Mound, 6 miles north of Yerrnilion, forming Turkey 

Eidge.

East of Spirit Mound no trace of it is found until Brule Creek is 

reached, 10 miles east. There it reappears, running northward to Beres18
TODD.] COURSE OF OUTER MORAINE. 19

ford, and thence north-northeast to the vicinity of Canton. From that 

place to the vicinity of Sioux Falls it seems not to have been formed, 

except at three or four isolated points. About 5 miles east-southeast 

of Sioux Falls it reappears on the west bank of the Big Sioux, and 

curves around the bend of the Big Sioux at Sioux Falls, and thence 

west and northwest to the vicinity of Montrose. From there it lies 

along the east side of the East Vermilion Elver to Vermilion Point, 

about 12 miles northwest of Madison. There it forms a reentrant angle 

by turning sharply to the east.

The map represents also the course of the moraine for some distance 

outside the limits chosen.

FROM TURTLE POINT TO PRATT CREEK.

We have found it convenient to begin at the prominent headland 

in Jerauld County known as Turtle Point. A view of this from the

FIG. 1. Turtle Point, from the northwest.

northwest is given in fig. 1. This forms the northern end of a high, 

even-topped ridge which extends from sec. 35, T. 108, E. 65, to the 

southern portion of T. 106, E. 65, a distance of 12 miles.

The point derives its name from the unique figure of a turtle, 1 rod in 

length, formed upon a mound capping the summit of the point. This 

figure is formed of small bowlders placed at short intervals so as to 

describe the outline of a turtle. The range extending south we shall 

call Turtle Eidge (PI. II). Its height above the plain to the east is 

nearly 500 feet. Its eastern face is quite abrupt, and along its northern 

portion is much marked by gulches, which arise from springs issuing 

from beneath the drift. One of them is known as Wessington Spring, 

which pours forth a copious supply of slightly sulphurous water.

These gulches seem very subject to landslides, which have repeatedly changed the location of the springs. This tendency to slide is 

probably the effect of water softening the clays below. Some of
20 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

these springs are connected with long, trough-like ridges. One, in 

particular, running east from an old exit of the Wessingtou Spring, 

is extraordinarily large. It extends eastward from the face of the 

ridge, 1£ to 2 miles, with a height midway of from 50 to 75 feet above 

the adjacent slope.

The western side of the Turtle Eidge subsides with a gentle slope to 

a broad, undulating plain, around the heads of Smith and Crow creeks.

FIG. 2. Map of Turtle Ridge and southwest Wessingtons.

This plain is considerably eroded near these streams. The top of Turtle Eidge is in several places rough and very stony, exhibiting the 

characters of a typical moraine. This is especially true toward its 

western side at the north end, and along the eastern side farther south. 

&mong these knobs are frequent basins, some of them containing water. 

A very remarkable feature in this ridge is a long, deep, narrow val-
U. S. GEOLOGICAL SURVEY BULLETIN NO. 158 PL. ll

VIEW OF TURTLE RIDGE FROM THE EAST, 

v Wessington Spring Gulch, vv Gulch connected with ancient channel (see fig. 2 and PI. III).
TODD.J COURSE OF OUTER MORAINE. 21

ley, with abrupt sides, extending from near the north end through the 

center of the ridge 6 or 7 miles toward the south. It then turns abruptly 

to the southwest and flows into Crow Lake. Tributary valleys beginning at the face of the hills, on either side, form with this central valley a complete drainage system. In the main channel are a few isolated 

domes 25 or 30 feet in height, apparently composed of gravel and 

bowlders. At different places in the channel are basins containing 

water which form considerable lakes, and are not improbably the 

sources of supply for the springs before mentioned. Muskrat Lake is 

possibly the principal supply of the Wessingtou Spring. Some of the 

ancient water channels have recently been eroded by water flowing 

eastward, either upon the surface or by springs cutting backward into 

the hills. A conspicuous example is represented in Pi. III.

The general arrangement of the drainage system is shown in the 

accompanying map, fig. 2.

An interesting question which may be conveniently discussed at this 

point is: How much of these high portions of the moraine is due 

to glacial action and how much to pre-Glacial topography? Turtle

FIG. 3. Transverse section of Turtle Kidge. v Turtle Point, w Ancient channel leading to Crow 

Lake, wv Crow Lake, ww Smith Creek.

Bidge affords several features which indicate that the glacial action 

has been the lea.st efficient of the two in other words, that the position 

and the greater portion of the mass are due to erosion antedating the 

glacier. As will be seen from the accompanying section fig. 3, there 

are exposures of sandstone in the east front of the hills in sec. 12, T. 

107, R. ,65. This sandstone is evidently similar to that capping the 

Bijou Hills and the buttes farther west. The deposit is not consolidated into a quartzite, as is usual in such localities, but shows similar 

structure even to the occasional occurrence of beds of grit between the 

finer layers.

Below the beds of sandstone are lead-colored clays, occasionally 

exposed in the deepest portions of the gulches. A more striking 

evidence of their existence is seen in the numerous landslides which 

have occurred near the various springs. The sulphurous ingredients 

of the waters are probably traceable also to the pyrites in the clays. 

Along the east foot of the ridge the drift is thin, arid wells frequently 

reach the Cretaceous clay 15 to 20 feet below the surface.
22 MORAINES OF SOUTHEASTERN SOUTH DAKOTA.

Another evidence of the influence of pre-Glacial topography is seen 

in the configuration of the country north of Turtle Ridge. Extending 

northwest is the edge of a terrace, quite distinctly marked, about 250 

feet above the level of the plain on the east. This terrace is covered 

with drift, and its edge is seamed with gulches, which are faint imitations of those in Turtle Eidge. It also abounds in bowlders, some of 

considerable size. A ready explanation of this feature would be that 

it marks the former edge of a great valley, more commonly known as 

the James Eiver Valley, and that the force of the ice sheet was 

sufficient to override this portion because of its lower altitude, while 

Turtle Eidge was able to hold its own against it.

Before proceeding further we may find illustrated in Turtle Eidge 

an iuterlobular moraine, as defined by Professor Chamberlin. It 

occupies the space between the shallower western lobe and the main 

body of the great Dakota lobe on the east. The internal drainage 

system already described was evidently occupied by super-glacial 

streams which entered it from either lobe and drained through Crow 

Lake into the present valley of Smith Creek. That these streams 

were of considerable size is indicated by the fact that the breadth of 

some of the outlets upon the face of the moraine is from 150 to 200 

yards. These valleys are flat bottomed, 90 to 100 feet in depth in the 

deepest portions. The gravel mounds before mentioned were .possibly 

formed by eddies in the stream. A similar internal drainage is found 

in the Eee Hills, Bald Mountains, and other interlobular moraines. 

Muskrat Lake is apparently formed by the partial filling of the principal channel by material brought in by the main western branch.

Among the bowlders found scattered in the Turtle Eidge two very 

large limestone bowlders were noted on the east brow of the hills, one 

9 by 7 by 2 feet, the other 20 by 9 by 2 feet. There are no bowlders of 

red quartzite, nor of local Tertiary quartzite and sandstones. Ordinary 

granite and greenstone bowlders abound.

Extending southward from near the middle of the east side of Turtle 

Eidge is a low morainic ridge, leaving it at a very small angle, and 

running 3 or 4 miles farther south, and subsiding gradually to the level 

of the eastern plain in the northern part of T. 105, E. 65. Between 

this and the principal range is a shallow valley occupied by the headwaters of the west branch of the Firesteel. This subordinate ridge 

is very stony. Whether the explanation of its existence may be 

similar to that of the terrace north of Turtle Eidge is uncertain. It 

seems not unlikely that it is a portion of a faint minor moraine found 

between the first moraine and the second, or it may be a subglacial 

moraine due to some uuevenness in the floor over which the ice was 

moving.1 Extending from a point about a mile south of Crow Lake to 

a point 3 or 4 miles west of White Lake, in a nearly direct line, is the 

axis of another high and massive ridge, which we will call the south.

1 Of. Dana, Am. Jour. Sci., 3d series, Vol. XXVIII, p. 230.
U. S. GEOLOGICAL SURVEY BULLETIN NO. 158 PL. Ill

VIEW OF OLD OVERFLOW CHANNEL IN TURTLE RIDGE. 

Turtle Point on the right.
TODD.] COURSE OF OUTER MORAINE. 23

west Wessingtons. Its eastern face, like that of Turtle Eidge, is steep 

for about two-thirds of its height, then descends by gentle slope to 

the plain southeast. This range is highest in the middle, where it has 

an elevation of about 300 feet, in the vicinity of Ishams Lake. Its 

western slope is not more than half as steep as its eastern, and declines 

gradually to Smith Creek, about 5 miles northwest, where the stream 

is over 100 feet lower than White Lake in the plain east, inside of the 

moraine, fig. 11 (p. 37).. While the range is massive, its summit is 

crowned with a few clusters of knobs, showing at a distance its morainic 

character. Among these knobs are the usual'basins and ponds, the 

largest of which is Ishams Lake, sec. 16, T. 105, E. 66. Between Turtle 

Eidge and the southwest Wessingtons there is a broad sag, the summit 

of its bottom being about 100 feet above the plain southeast. In about 

the center of this pass or sag is a remarkable system of sharp, stony 

ridges from 10 to 30 feet in height, extending from near the southeast 

corner of T, 105, E. 66, in a curve corresponding to the lower portion 

of the sag to the southeastern part of Crow Lake. The general features 

of the system may be more fully understood from the accompanying 

map, fig. 4:

r^^°'x -~-i'

r^' " r^ v '"'4=

Fig. 4. Map of osar-like ridges near Crow Lake.

These stony ridges are osar-like and are probably connected with 

former drainage from the ice sheet.

At the southern end of the southwest Wessingtons is a similar but 

less marked pass through the moraine, by which water probably escaped 

into a valley connecting with the head waters of Smith Creek. From 

this outlet the moraine is less conspicuous, evidently not having so 

high a pre-Glacial surface on which to rest. A scattered series of 

morainic hills may be traced southwest past Kimball to the middle of
24 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

the western side of T. 103, E. 68. This system of hills is from 2 to 5 

miles in breadth, its inner and outer limits not being very clearly 

defined. Along its outer limit west of Kimball is a valley running 

southwest, connecting the valley of American Creek with Eed Lake 

and the Missouri. The inner ranges of the moraine are but little higher 

than the subdued swells of the glacial topography upon that side. 

About 4 miles east of Kimball the railroad crosses two well-defined 

valleys, which head on the inside of the moraine. They doubtless indicate lines of drainage dating back to the time of the ice sheet. One of 

them connects with American Creek and the other with Smith Creek.

From near the middle of the west side of T. 103, E. 68, these morainic 

ridges begin to describe a semicircular curve toward the northwest, 

the outer range of which lies about along the east side of Eed Lake. 

The principal ridge in the curve presents an abrupt and stony inner 

slope and a gentle outer slope, with few bowlders. From the southFIG. 5. Portion of the moraine near Bijou Hills, v Moraine.

ern terminus of this semicircle, near the southern line of T. 103, E. 69, 

the moraine seems still less defined, but as it approaches the east end 

of the East Bijou it regains its character of broad, stony ridges separated by sags with ponds, the ridges being from 30 to 40 feet higher 

than the plain within. Lying against the eastern end of the East Bijou 

is a high north- and-south ridge over 100 feet in height (fig. 5), and apparently composed entirely of drift. South of the East Bijou the glacier 

at some time evidently pushed farther west, perhaps nearly to the western end, but such occupation was comparatively temporary. Masses 

of bowldery clay are found on the highest summit of the East Bijou, 

toward the south side and near the southwest angle of the hill. South 

of the Bijou Hills the moraine is again ill defined. 

On or near the middle of the western line of T. 100, E. 69, is a well-
TODD.] COURSE OF OUTER MORAINE. 25

defined north-and-south ridge extending 2 or 3 miles. Its height is 

over 100 feet. Its northern end terminates rather abruptly amid a 

cluster of ponds of considerable size.

Extending inside of the principal portion of the moraine, from near 

the northwest corner of T. 101, E. 68, 7 or 8 miles, in a south-by-east 

direction, is a remarkable chain of lakes or lake beds occupying a broad, 

shallow valley. Southwest of the east end of the East Bijou is another 

 cluster of lakes, with a valley connecting them with the head waters of 

Snake Creek. It is probable that these two systems of lakes occupy 

an old channel leading into Snake Creek.

Northwest, west, and south from the short ridge last described are 

lower stony ridges, which are doubtless a portion of the moraine. 

Besides these we find no trace of the moraine till we reach the hills 

around Cedar Creek, which occupy the central portion of T. 98, R. 68. 

The-plain on the inside of the moraine is quite even, extending sharply 

down to the east bank of the Missouri. In it Pratt Creek has excavated 

a narrow valley about 200 feet in depth. East of its junction with the 

Missouri there is a high terrace, capped with an abundance of gravel 

and bowlderets.

FROM PRATT CREEK TO RUNNING WATER.

The Cedar Creek Hills receive their name from a very short stream 

called Cedar Creek, which is surrounded by them. They extend some-

. G. -Cedar Creek Hills, from the north, v Pratfc Creek, w Missouri River. v v v Driftless bluff.

what in the form of a V, with its apex pointing northeast and subsiding 

gradually into the plain on or near sec. 15, T. 98, E. 68 (fig. 6). The 

northwestern arm of the V, which is not very prominently developed, 

extends for 2 or 3 miles along the northern side of the stream. The 

southeastern arm extends in an irregular manner southward along the 

top of the east bank of the Missouri, connecting with the hills northeast of Wheeler. This continuation of the moraine has been under-
26 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BOLL. 158.

mined by an east bend of the river above Wheeler until apparently 

half of the moraine has been removed. Its appearance is shown in 

fig. 7. This view presents the nearest approach of the inside of the 

moraine to the Missouri Eiver at any point between Pratt Creek and 

Choteau Creek.

From this point, which is on or near sec. 23, T. 97, E. 68, the inner line 

of the moraine may be described as follows: It extends east-southeast 

to the southwestern end of Lake Andes, thence from the southwest 

corner of sec. 12, T. 69, E. 65, near the south shore of Lake Andes southward along the east side of the township nearly to its southeastern 

corner, and thence south-southeast in nearly direct line to the middle 

of T. 94, E. 62.

The structure of the moraine through this portion is found to be a 

deep deposit of drift, overlapping hills of Cretaceous clay. The moraine

FIG. 7. The moraine half eroded by the Missouri.

presents few knobs upon its surface. It may be described as a broad 

swell, with a somewhat abrupt slope toward the northeast and an irregular gentle slope toward the southwest, which latter is much seamed 

by short streams draining into the Missouri. It is interesting to find 

this portion of the moraine mapped as a ridge on Gen. GL K. Warren's 

map of 1857.

Through it are three important outlets, extending upon or a little 

below the level of the plain northeast. The first of these is now occupied by Pease Creek and another smaller stream. This outlet is from 

one-half mile to 2 miles in width, and is flat-bottomed, especially upon 

the western side, the eastern being occupied largely by a system of 

high, stony hills resembling osars. Another outlet is that extending 

southwest from the end of Lake Andes (PL IV). This also is occupied
U. S. GEOLOGICAL SURVEY BULLETIN NO. 158 PL. IV

^Wgitei!

LAKE ANDES OUTLET FROM THE NORTHEAST, 

v Moraine, v v Bluffs across Missouri River, showing through Lake Andes Gap.
TODD.]. COURSE OF OUTER MORAINE. 27

by a small stream, which flows along the western side, and also a dry 

drainage channel, a few feet in depth, from Lake Andes itself. The 

eastern side of this outlet also presents prominently the effects of running water, in the form of gravel terraces. Another less important 

outlet extends west-southwest from near sec. 25, T. 96, E. 65, till it 

joins the Andes Outlet before it reaches the river. From its relation to 

a grassy lake of considerable size northeast of it in the plain, I have 

called this Grass Lake Outlet. All of these outlets present the features 

of nearly straight troughs, with sides quite abrupt, especially the western. 

Their bottoms are in every case lower than the general level within the 

moraine, and slope more or less rapidly to the surface of the lower 

gravelly terrace described in Chapter Y. Near the head waters of 

Sevenmile Creek, at the southwest corner of T. 96, E. 64, the moraine 

declines in elevation from 75 to 50 feet, and at the same time seems to 

broaden, and continues this character from this point to Choteau Creek.

Several streams have their valleys heading in close to the northeast

FIG. 8. General view of the moraine from 2 miles south of Grandvie-w. Numbers indicate degrees

from south.

side of the moraine and probably were minor channels of overflow when 

the ice was forming the moraine. A distant and general view of this 

part of the moraine is shown in fig. 8.

A conspicuous point in this lower portion of the moraine is on or 

near sec. 30, T. 94, E. 62. It is situated some distance outside of the 

inner boundary of the moraine, so that it seems never, or very briefly, 

to have been covered by the ice. It presents the well-marked layers of 

the Bijou quartzite, lying in horizontal position, and scattered upon 

them numerous bowlders of all kinds. Its altitude is quite definitely 

determined to be 1,675 feet.

A view from the summit of the moraine shows, in general, a gentle 

slope down to the level of a high terrace along the left bank of the 

Missouri. This terrace averages over 200 feet above the river.

The valley of Choteau Creek, as it approaches the moraine, is from 1J 

to 2 miles in width and flat bottomed, apparently marking another outlet, which, however, instead of going straight toward the Missouri, turns
28 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

eastward and joins a drainage valley from the interior of the Choteau 

Creek Hills. This latter valley, from the scantiness of water in it, is 

known as the Dry Choteau, while the more extended western branch 

is locally known as the Wet Choteau. The Choteau Creek Hills are a 

system of morainic hills surrounding the Dry Choteau. They extend 

north and south and are estimated to be 3 to 5 miles in width. Their 

northern end occupies the west half of T. 97, E. 61, and is surrounded 

with a broad, semicircular valley, in which rise the headwaters of 

Emanuel Creek on the east and an important branch of the Wet Choteau on the northwest. This valley is most abrupt on its outer side, 

and has a depth of 60 to 100 feet below the plain outside. The plain 

ends in a terrace-like edge, in some places considerably raised above 

the region farther back. This is markedly true of the portion east 'of 

the hills, near Aden post-office, sec. 1, T. 97, E. 61, where the surface 

suggests a minor moraine. The hills terminate southward in narrow 

but prominent ranges near the mouth of Dry Choteau. This is particularly true of hills on the east side of the system. East and southeast of that point there is a broad swell, evidently passed over by the 

ice and suggesting an advance of the ice farther west in its later occupation of the region. Perhaps the erosion of the waters escaping from 

the valley had removed the moraine on that side, so that the ice broke 

over the remainder into the drainage valley itself. That their location 

was probably predetermined by hills of Cretaceous clay is indicated by 

the reported occurrence of chalkstone some distance above their base 

at the northern end. This was not certainly determined to form a 

ledge, but was found in such quantity as to render it quite certain that 

such was the case. Several important lakes and marshes occur in the 

hills.

The ice sheet evidently very nearly surrounded these hills, as the 

small lobe extending east of them pushed through quite to Choteau

Creek in T. 93, E. 61. It also reached nearly to the present course of 

the Missouri. There are, however, high northwest-southeast ridges 

extending from near the mouth of Choteau Creek to sec. 3, T. 92, E. 

61, where they are more developed than farther west, rising over 150 

feet above the plain to the northeast and estimated to be fully 400 feet 

above the river to the north. They are so cut by ravines from the 

river as to make their morainic character somewhat questionable. 

Fortunately, in an old well evidence was found of an ancient pond 

upon this hill, containing specimens of fresh-water shells and having 

every appearance of a morainic basin, which had been filled with 

earth 8 or 10 feet in depth.

EMANUEL CREEK GKA.P.

From this point no trace of anything that can be called a moraine is 

found until we reach the bluffs about 5 miles east of Bonhomme. Over 

this region, on the north side of the river, the plain, gently undulating, gradually subsides to the level of the lower, bowldery terrace,
U. S. GEOLOGICAL SURVEY BULLETIN NO. 158 PL. V

 « *! ;il>^/j^'l'/e|^<>r- ^ ^f^iftv"5

f SV v - I-£i?-f^^-'_ . ^T^.^-^ c'

JAMES RIDGE FROM THE NORTH. 

Mount Pisgah. v Exit of James River through moraine, vv Exit of Beaver Creek. %vv Entrance cf Beaver Creek.
TODD.] COURSE OF OUTER MORAINE. 29

which has an altitude of about 200 feet above the river. The surface 

js somewhat lower in the vicinity of Springfield. North of Bonhomme, 

in the valley of Snatch Creek, the general surface is still more depressed, and abounds in low bowldery knobs. It suggests the filling of 

a pre-Glacial valley. This is further indicated by a gap in the chalk 

bluffs along the north side of the Missouri.

Upon the south side of the river, back from the bars and bottom 

laud immediately adjacent to the channel, is a strip of country from 

2 to 4 miles in width displaying very little drift, and underlain by 

chalkstone below and Cretaceous clays above, with much sand, probably 

of Loup Fork epoch, still higher. This region is very much eroded 

by small streams running north to the river. South of this strip of 

country there rises abruptly the northern edge of a table-land, built of 

beds of sand arid gravel below and of loess with a few scattered bowlders above. The loess is much eroded, but its valleys extend away from 

the river into the branches of Bazile Creek. One peculiar feature of 

the northern edge of this table-land is the projection of high ridges of 

the loess extending 1£ to 2 miles northwest, without diminishing in 

altitude, over the Cretaceous region before described.

It seems clear that in this gap of the moraine we have trace of a 

relation of ice sheet and river similar to that which existed between 

the Bijou Hills and the Cedar Creek Hills, though on a vaster scale: 

with the difference, however, that in that case the water was flowing 

rapidly transversely to the motion of the ice, while in this case it was, 

perhaps, discharging more in the same direction.

FROM BONHOMME TO SPIRIT MOUND.

The moraine appears on the north bank of the river, about 5 miles 

east of Bonhomme, in a high, broad swell, extending from the southwest toward the northeast, past Lakeport, which is situated on the 

inner crest of the moraine; but it rather abruptly turns eastward and 

declines in height near the center of T. 94, E. 57, where there seems to 

have been a broad outlet, or perhaps a tongue of the ice in the place 

now corresponding to the upper valley of Beaver Creek. Later there 

seems to have been much water flowing southeast over this area.

Near Lesterville a considerable cluster of morairiic hills again appears, 

about 50 feet in height above the plain around them. These seem to be 

an interlobular portion of the moraine between the broad valley to the 

south and a narrower valley coming in from the north along their east 

side, or else a local development of a later moraine not usually appearing, possibly an earlier portion of the second moraine.

Again, beginning near the southeast corner of T. 96, E. 57, a high, 

sharp, continuous ridge extends in a nearly direct line to sec. 12, T. 94, 

E. 56, where it quite abruptly declines in height, apparently having 

been washed away by water from the west. Through this range is an 

interesting gap through which Beaver Creek crosses it toward the east,
30 .MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

upon sec. 28,» T. 95, E. 56. South of this is a conspicuous peak, locally 

known as Mount Pisgah. An interesting drainage channel at higji 

level crosses the moraine north of the gap on the west Hues of sees. 16 

and 21, T. 95, E. 66. A conspicuous view of this portion of the moraine 

from the inside is given in PI. V, and from the outside in fig. 9. Another 

drainage channel at higher level runs south obliquely across it along 

the west line of sec. 16, T. 95, E. 56.

A few morainic points in a ridge running east-west, northeast of 

Lakeport, suggests the idea that the broad gap south of Lesterville 

may at one time have been occupied by a small lobe from the ice sheet 

west. The highlands west of Yankton descend in a long, gentle slope 

from the vicinity of Lakeport to Tankton. This slope is traversed by 

valleys extending south of east which bear traces of running water. 

There are gravelly knolls and terraces, especially toward the foot of 

the slope. From the gap east of Lesterville extends a broad valley, 

running southeast. Just southwest of James Eidge this also opens

FIG. 9. James Kidge, from the west, v Beaver Creek, vv Mount Pisgah.

toward the southeast upon a broad gravelly terrace, through which 

Beaver Creek in its lower portion has excavated a deep valley. James 

Eidge in its northern half seems to have been a narrow interlobular 

portion of the moraine. A lower bowldery ridge, somewhat detached, 

skirts its northern end much as in the case of the Choteau Creek Hills.

From a consideration of the topography of the gorge-like character 

of the trough of the Missouri from Bonhomme to Yankton, of the 

occurrence of blowing wells near Utica, and of the finding of fragments 

of quartzite like that of the Bijou Hills at the south end of James 

Eidge, it seems probable that before the advent of the glacier the Missouri, or rather the Mobrara, flowed northeast from Springfield and 

thence eastward north of Lakeport and Yankton to join the main river 

northwest of the latter place.

Extending along the east side of James Eidge, separated from it on 

the south by Beaver Creek, and turning east from the southern end of 

the higher part of James Eidge, is a morainic ridge, at* one time 

thought to be a part of the outer moraine, but a more satisfactory
U. S. GEOLOGICAL SURVEY BULLETIN NO. 158 PL. VI

-,, - v/#:-'" vAr 1 -^^'V.-- 1 ^'-il1\;^'T-'r-^v^-r-': ^V/--'"r- ' :- ^-"^i ?

 i-'-^¥'^^^5|^

THE ATTENUATED MORAINE NEAR VERMILION RIVER, 

v Missouri River, vv Spirit Mound.
TODD.] COURSE OF OUTER MORAINE. 31

interpretation makes it a part of the second moraine, under which head 

it is further discussed.

East of Clay Creek morainic ridges appear again on or near sec. 26, 

T. 95, E. 54, where they are well developed along the east branch 

of Clay Creek.

From this point the more or less morainic west slope of the highland 

runs nearly northwest to the southeast corner of T. 98, E. 55. The west 

branch of Clay Creek flows along southwest of it in a southeasterly 

direction. Along the east branch of Clay Creek the chalkstone of the 

Niobrara group appears high up in the hills, rising some 80 feet above 

the waters of the stream. It is finely exposed as far north as sec. 17, 

T. 95, E. 54.

In the vicinity of Childstown post-office the moraine swings in a 

curve east, northeast, and finally around southeast along the west side 

of Turkey Eidge Creek, extending approximately parallel with the 

moraine just described, and forming with it a broad, high ridge, from 4 

to 6 miles in breadth. Its eastern limit, corresponding to the inside of 

the moraine, extends from Spring Valley post-office, east of Irene, to 

the vicinity of Wakonda, then more southward and then southeasterly 

into the northwest corner of T. 93, E. 52, where it turns more east, 

declines in height, and becomes broken into detached hills, the last of 

which is Spirit Mound (PI. VI).

This is a picturesque peak, rising nearly 125 feet above the level of 

the plain, upon sec. 14, T. 93, E. 52.

Turkey Ridge. Turkey Eidge exhibits the usual features of interlobular moraines. It shows a core of Cretaceous chalkstone and clay, 

above which there generally seems to be a mantle of fine deposits, possibly eolian, probably of Tertiary age. In some places this is a fine 

silt, resembling loess, but more generally it is very fine sand. Some of 

it may have been derived from glacial action, deposited before the ice 

sheet covered this point. Above this rests a much thicker mantle of 

till, 50 to 200 feet thick, except where cut through by erosion. No trace 

of a composite character has been found in this, though it has been 

penetrated at many parts by deep wells. The more reliable source of 

water is the fine sand or chalk below. The water in the two may be 

confluent.

The main internal drainage channel is Turkey Creek, which evidently 

received its waters from the east side, where two prominent cols are 

found, one at an elevation of about 1,450 feet above sea level in sec. 30, 

T. 97, E. 54, another at an elevation of about 1,318 feet, a little south of 

Irene.' Both of these, especially the latter, have been cut down nearly 

100 feet since they were first traversed by the water. Traces of drainage from the west are found at two or three points, but the ice there 

was lower and soon the drainage was along the line of Clay Creek, 

which ran along the west side of the interlobular moraine. These 

two channels converge to the vicinity of Voliu. Turkey Creek has a
32 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

naturally narrow valley, bounded by chalk cliffs rising from 50 to 100 

feet above the water. Turkey Eidge is about 24 miles long and from 

5 to 7 miles wide. Its surface is not very rough. Most of it is 

easily tilled, though in some places it is very stony. The prevailing 

stone is red quartzite. Its highest point is about 1,750 feet above tide, 

on sec. 5, T. 97, E. 55. From that place it declines quite regularly to 

about 1,400 feet for 2 or 3 miles west of Wakonda. A plan of it is given 

in PI. VII j see also sections E-F and I-K with the general map (PI. I). 

This is derived from the topographical survey of the United States 

Geological Survey made in 1896. In the later stages of the occupation 

of the moraine, as the ice thinned, the internal drainage ceased and the 

Vermilion lobe discharged along the line beginning in the eastern part 

of T. 97, E. 59, and extending to 2 miles west of Viborg, passing through 

the west side of T. 92, E. 52, thence nearly due south to sec. 9, T. 94, E. 

52, thence southeast to the Vermilion Eiver, passing just west of Spirit 

Mound.

VERMILION GAP.

From this point there is a gap in the moraine about 8 miles in width. 

It is occupied by the very level plain along the Vermilion Eiver. This 

plain extends southward and ends as a high terrace, the southern eud 

of which extends from the mouth of the Vermilion nearly due east to 

the Big Sioux. It rises about 100 feet above the Missouri. This terrace, 

as exposed by cuts in the vicinity of Vermilion, is composed of blue 

bowlder clay below, containing pockets of sand, and passing above into 

yellow pebble clay, and this is capped in places with a silt indistinguishable from loess. The surface of this terrace frequently exhibits 

basins similar to those found upon till; and from the relation of the 

terrace to the moraine it was probably occupied by a narrow tongue of 

ice running down the pre-Glacial Vermilion Valley into the Missouri.

FROM BRULE CREEK TO CANTON.

Along the west bank of Brule Creek, as far south as sec. 13, T. 92, 

E. 50, and still more prominent in the northwest corner of T. 93, E. 50, 

and the southwest corner of the township north, the moraine appears 

in a few scattered knobs of drift. Between these hills are evidently 

overflow channels from the plain northeast to the valley of Brule Creek. 

Some of their outlets are partially occupied by small lakes. These hills 

toward the north become connected into a broad swell composed of 

bowlder clay, which rises and broadens toward the north and extends 

past Beresford, situated upon its summit, thence north and northeast 

to the middle of the southern line of T. 98, E. 49, where it terminates 

abruptly, overlooking a broad valley, which slopes from the plain northwest down into the valley of the Big Sioux at Canton.

This portion of the moraine is not traversed by overflow channels of 

any considerable size, at least none have eroded the moraine very deeply.
U.S.GEOLOGICAL SURVEY BULLETIN NO. 158 PL.YII

EDGE OF ICE AND I^JMORAINE MarioiX "~ 

/VVWN ED(5E OF ICE AND 2".° MORAINE 

-=^5. ANCIENT DRAINAGE CHANNELS

Contour Interval lOOfeet

MAP OF TURKEY RIDGE, BY J. E. TODD, 1898.
TODD.] COURSE OF OUTER MORAINE. 33

There are, moreover, few knobs or morainic points exhibited by this portion of the moraine. It forms the western edge of a highland region occupying the whole area between it and the Big Sioux River on the east. 

This highland region is uniformly covered, especially upon the hilltops, 

with loess, some of the points of it rising higher than the nearer 

portions of the moraine. Branches of Brule Creek and the Big Sioux 

have eroded the whole surface of this highland so that the height of 

the hills above the valleys is often more than 150 feet. That there was 

more or less overflow across the moraine is indicated by numerous 

broad, marshy valleys extending from the summit of the moraine southward into Brule Creek. This is especially true in the vicinity of Beresford and south of Canton. At the northern end of the highland region 

it rises about 300 feet above the Big Sioux, and the valleys heading 

near the moraine are narrower and deeper than those farther south.

One of the most instructive portions of the moraine in this region, and 

indeed in any region, is that lying along the west side of Brule Creek, 

through Ts. 94, 93, and 92, B. 50. In the northern part of the first 

mentioned the moraine has the same features as near Beresford, and 

passes gradually into the eroded highland region farther east. This 

ends.in sec. 17, and farther south there is an alternation of drainage 

channels with bowlder knobs. This is represented in part in PI. VIII. 

These outlet channels are upon the same level as the plain farther west, 

and from 30 to 50 feet above the water in Brule Creek. In some of the 

wider it would seem that the ice occupied the channel and left ponds 

and bowlders over the surface, as in the common glaciated areas. These 

knobs rise over 100 and 150 feet above the creek and from 60 to 70 feet 

above the surrounding plain. The channels are not all upon the same 

level, but are deeper toward the south. Their eastern surface is 

mantled with loam, indistinguishable from loess. It has not been 

found, however, more than 5 or 6 feet deep, and it is not difficult to 

account for the numerous cases by eolian action in time of northwest 

winds. East of the creek the till rises to about the same level as 

that which forms the body of these knobs. At several points along 

the creek, and 50 to 70 feet above it, there are thick deposits of sand 

and gravel directly underlying the loess, which is much deeper upon 

the eastern side of the creek. The relation is shown in one of the sections in PI. VIII. Between sees. 8 and 9, T. 93, K. 50, the stream flows 

through a narrow gorge which seems to owe its character partly to the 

slipping masses of loess. From that point to sees. 24 and 25, T. 92, K. 

50, there is no morainic material west of the creek, but at the latter 

point the hills again appear very distinctly on the west side of the 

creek. It is evident that Brule Creek began its course when the ice 

occupied the Vermilion Valley as far south as the Missouri, and that the 

ice rose nearly or quite as high as the general level of the loess farther 

east. The question presents itself whether the water during the early 

occupation of the moraine flowed as high as that level, so as to disBull. 158 3
34 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

charge eastward over the loess of Brule Creek. There are some things, 

both at this point and in the vicinity of Fairview, which seem to indicate this condition. For example, the width of Brule Creek between 

sees. 8 and 9, T. 93, E. 50, seems too narrow for the width of the 

valley farther north and the numerous outlets leading to it. Again, 

south of Beresford, but more north of that place, while there are no 

prominent drainage channels, there are shallow ones which cross the 

moraine at a high altitude, some of them as high as and even higher 

than the level of the loess farther east. Moreover, northeast of Beresford there is a peculiar mingling of bowlder knolls and loess, as if the 

loess portion of it had been deposited in the valleys of the till.

BIG SIOUX GAP.

From the northern end of the highland south of Canton to the highland south of Sioux Falls, on sec. 29, T. 101, E. 48, we have again a 

depauperated portion of the moraine. It is only represented by a few 

isolated hills lying along the west bank of the Big Sioux. They present at first sight the peculiar phenomenon of detached portions of the 

table-lands east of the Big Sioux. They rise to nearly the same height 

and are about 150 feet above the plain to the west. The first of these 

is about 1 mile northeast of Canton a low hill composed largely of 

gravel, rising about 150 feet above the river. The second is a much 

more important hill, occupying much of sec. 6, T. 98, E. 48; the third a 

hill occupying sec. 20, T. 99, E. 48; the fourth, in or near sec. 15, T. 

100, E. 49. These hills are composed of drift, and when of any size 

show basins indicating their morainic character. Between the highland 

south of Canton and the hill northeast there is a broad incline from 

lie plain on the northwest to the level of the Big Sioux. Upon this slope 

two or three terraces may be traced. The plain on the northwest rises 

about 130 feet above the river. Continuous with the higher of these 

terraces, which is the more stony, is a long bowldery terrace extending down the Big Sioux, and gradually declining in altitude to the 

valley of the Eock Eiver. It reminds one of the terrace on the Missouri 

extending from the mouth of Pratt Creek southward. The valley of 

the Big Sioux here is narrower, apparently not more than half the 

width of the Eock Eiver. This is especially true in the vicinity of Fairview. This suggests its recent excavation, perhaps during the later 

occupation of the principal moraine.

North of Canton the plain to the west comes up quite sharply to the 

valley of the river, leaving a terrace-like edge, except in the vicinity of 

small streams emptying into the Sioux. East of the Sioux, as before 

intimated, the general level is from 200 to 250 feet above the river. No 

trace of Cretaceous clays was clearly noted along the Big Sioux above 

Canton till the northwest corner of Iowa was nearly reached. It is 

probable that they rise from 25 to 50 feet above the present stream. 

Northwest of Canton the chalkstone of the Mobrara group occupies
U. S. GEOLOGICAL SURVEY BULLETIN NO. 158 PL. VIII

DETAILS OF THE MORAINE IN UNION COUNTY, SOUTH DAKOTA.
TODD.] COURSE OF OUTER MORAINE. 35

the bank of a small stream at a height of nearly 100 feet above the Big 

Sioux. There seems to be no evidence that any portion of the east 

bluffs of the Big Sioux represents any part of the moraine.

FROM THE BIG SIOUX TO VERMILION POINT.

Beginning on the west side of the Big Sioux, about a mile north of 

the northern boundary of Iowa, a high massive ridge begins to extend 

westward and southwestward around the Great Bend of th'e Big Sioux, 

and continues its westerly course to near the southwest corner of 

T. 101, B. 51. Thence curving northward, it crosses the Chicago, St. 

Paul, Minneapolis and Omaha Eailway about 4 miles east of Montrose, 

then closely follows the east side of the East Yermilion, crossing the 

Chicago, Milwaukee and St. Paul Railway west of Winfred, and continues in that direction to a point about 12 miles northwest of MadFio. 10. Inner slope of the moraine south of Wall Lake.

ison. The line indicated marks its inner slope. Its outer slope is less 

distinctly marked, being irregular, but usually with slight descent 

toward the north and east. Of the portion just traced, that immediately south of the bend of the Big Sioux is the lowest, rising only about 

120 feet above the water in the river. It bears traces of several drainage channels, as though considerable water had been discharged northward from this point. About 3 miles southeast of Sioux Falls is the 

highest point east of the bend. It rises about 265 feet above the river to 

the east, or 165 feet above the Chicago, Milwaukee, St. Paul and Omaha 

station at Sioux Falls. In this elevated portion the moraine has been 

least modified, and therefore shows its usual characteristics stony 

knobs and ridges, with ponds. The moraine has been crossed in the 

vicinity of Wall Lake, east of Montrose and east of Winfred. At the 

first of these points its height is 175 feet above the plain to the south-
36 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

west. East of Montrose and east of Winfred the altitude is about 200 

feet. At all of these points the inner'surface of the moraine is very 

stony and unusually marked with knobs, which are more numerous 

upon the inner slope than upon the summit of the moraine (fig. 10).

As one looks from the moraine toward the outside the view is like 

that of a plain, with numerous ponds in places. Elsewhere these ponds 

seem to have been drained by shallow channels of erosion, connecting 

with Skunk Creek. These channels are not uniformly from the inner 

surface of the moraine outward, but often parallel to it, or even 

occasionally flowing toward it. In these shallow valleys are soinetimes 

found systems of elongated, sharp, stony ridges. One example was 

noted along a branch of Skunk Creek in the southwest corner of T. 

101, E. 50. Another and more extensive system is found about 5 miles 

from Montrose, leading from a shallow gap in the moraine and extending to a branch of Skunk Creek. (Pis. IX and X.) A fuller description will be given in a later chapter.

The outer surface of the moraine gently declines to the surface of 

an undulating plain traversed by channels to® large for their present 

streams. This portion of the moraine has no deep outlet channels 

traversing it. Its summit is not very rough, but from Hartford to 

Eussell it is from 8 to 10 miles wide, and its outer slope abounds in 

prominent stony knobs and ridges interspersed with lakes.

Yermilion Point is the termination of Vermilion Eidge, where it 

gradually subsides into the undulating plain on the north. Instead of 

resting upon the edge of an elevated terrace like Turtle Point, it 

lies on a plain running eastward. For this reason it is not nearly so 

prominent.

This completes the tracing of the outer moraine in the region chosen 

for consideration.

From Yermilion Point the moraine turns sharply east and northeast, 

and after crossing Battle Creek about 6 miles south of Madison, it 

quickly turns to a northerly course and passes 4 or 5 miles west of 

Volga. The southern side of this loop is slightly developed, or much 

eroded, but the eastern is very rough. It does not present the appearance of a broad swell, as in much of its course, but a disorderly mingling of frowning knobs and ridges, with narrow and broad channels 

which are frequently studded with lakes. The outer boundary of the 

moraine in this portion is marked by the northeasterly portion of Battle Creek and the flood plain of the Big Sioux farther north.

GENERAL CHARACTERISTICS OF THE MORAINE.

The term moraine, although already frequently used in this paper, 

has not been clearly denned. It is a word introduced from the French, 

but may be traced with the Italian mora, a heap of stone, and the 

Spanish moron, hill or hillock, to the Latin murus, which not only has 

the primary meaning of "wall," but also "dam," "edge of a pot," etc.
U. S. GEOLOGICAL SURVEY BULLETIN NO. 158 PL. IX

CHANNEL, LAKE, AND OSAR RIDGES NORTHEAST OF MONTROSE. 

v v Plain inside or west of the moraine.
TODD] STRUCTURE AND POSITION OF OUTER MORAINE. 37

Both wall and rim of a pot are instructive comparisons in forming an 

idea of moraine as used in this paper.

Moraine, as commonly used, includes all the debris, bowlders, pebbles, sand, and clay which is transported and deposited in various 

situations by a glacier. The moraine of which we speak in these pages 

is always the system of hills believed to have been heaped up around 

the edge of an ice sheet. Such hills are recognized as belonging to the 

moraine more by their relative position than by any one character 

which they bear individually. > Each one is usually circular or lengthened parallel with the course of the system, abounds in bowlders, and 

has quite abrupt sides, but none of these characters are always found.

As a system the moraine usually presents these stony, knobby hills, 

mingled confusedly with circular and winding basins, which often contain water, but sometimes both basins and hills are very faintly developed, so that the whole constitutes a broad swell. The moraine is 

traversed here and there by transverse valleys, by which water escapes 

from the ice sheet. These may be of trifling size or many rods in width 

and cutting down through the whole height of the moraine.

The height of the moraine at any point is due, first, to the relative 

elevation of the pre-Glacial surface; second, to the amount of material 

pushed forward, which itself depends upon the pushing power of the 

glacier and the time its edge remains stationary; third, to the amount 

of material washed away; and, fourth, to the consistency of the material. Excess of clay or sand tends to produce a low and even moraine, 

while excess of stony material is favorable to the formation of a high 

and rugged moraine.

STRUCTURE AND POSITION.

A cross section of the moraine where least modified is a broad, low 

scalene triangle, the shorter side being inside, the longer, considerably

FIG. 11. Section of southwest Wessingtons.

less abrupt, being outside. Much of the moraine, however, is so modified that these features do not appear. Portions best illustrating the 

character mentioned are found where the moraine is neither doubled 

upon itself nor closely adjacent to an important drainage channel, as, 

for example, the southwest Wessington Hills (fig. 11), the portion 

between Lake Andes and Choteau Creek, and the portion between 

Vermilion Eiver and Canton, and again from Sioux Falls to Winfred. 

As has been already intimated, the pre-Glacial topography is believed
38 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

to have had great influence upon both the course and the character of 

the moraine. For example, the locations of Turtle Eidge, Choteau 

Creek Hills, and Turkey Eidge are doubtless due to the positions of 

high pre-Glacial buttes. The position of Vermilion Eidge seems'rather 

determined by the distance which the ice sheet could force itself up an 

inclined plane. The subordinate lobes, as in the case of the Dakota 

lobe itself, were primarily determined by the existence of valleys down 

or up which the ice pushed its way.

HEIGHT.

The moraine has an elevation, above the plain inside, of from 50 to 

400 feet. Its average height is about 100 feet. The extreme elevations, 

as, for example, in Turtle Eidge, are in localities nearer the center of 

the ice sheet, where we may suppose its thickness was greater and its 

transporting action more pronounced. The lowest portions are found 

apparently either where the ice sheet extended into ponded waters or 

where it was acted upon by floods of water coincident with or subsequent 

to its formation. An example of the first case is found north and south 

of the Bijou Hills. An example of the second is found in the lower portions of the James and Vermilion valleys. It seems not improbable 

that some of the less developed portions of the moraine are to be 

accounted for by their distance from the source of material and their 

transient occupation by the ice sheet. For example, the ice can hardly 

be conceived as occupying the moraine in the vicinity of Kiinball as 

long as it did in the vicinity of Wessington Springs or of Lake Andes. 

It seems not improbable, also, that, other things being equal, if the 

drainage of an ice lobe is lateral an excess of material would be found 

near the termination of a glacier rather than in its lateral portions. 

This may explain the height of the moraine in the vicinity of Lake 

Andes.

The outer or principal moraine, in general, appears to increase in 

height toward the north, and still more toward the west. Both of these 

features will be seen from the following table:

Table showing heights of outer moraine.

Locality.

West of Russell................ ......

West of Hartford. ....................

South of Wall Lake ...................

Southwest corner T. 99, R. 48 ..........

Elevation above 

Kiver 

outside.

330

289 

247 

130 

265 

200

Plain 

inside.

200 

200 

200 

175 

125 

155 

110

Sea.

1,825 

1,740 

1,692 

1,650 

1, 519-1, 525 

1,555 

1,525

Highest 

rocks 

near by.

120
U. S. GEOLOGICAL SURVEY BULLETIN NO. 158 PL X

CONTINUATION OF OSARS NORTHEAST OF MONTROSE.
TODD.l . HEIGHTS OF OUTER MORAINE. 

Table showing heights of outer moraine Continued.

39

Locality.

Sec. 31, T. 94, E. 53...... ..............

Sec. 31, T. 94, K. 53.... ................

Sec. 5, T. 97, R. 55. ....................

Sec. 28, T. 95, R. 54.... ................

Sec.7,T.94, R. 55. ....'................

Mount Pisgah, (sec. 34, T. 95, E. 56) ....

Sec. 3, T. 92, R. 61. ....................

Sec. 4, T. 95, R. 61. ....................

North end of Choteau Creek Hills. . ..

East center T. 95, R. 62. ...............

Prospect Point (sec. 8, T. 97, R. 61) .....

Northeast corner T. 94, R. 63 ..........

South center T. 94, R. 62...... ........

South of Lake Andes. ................

Sec. 6, T. 96, R. 66. ....................

Sec. 24, T.97,E. 68..... ....... ........

Sec. 28, T. 98, R. 68...... ..............

East end of East Bijou.. ..............

North of end of East Bijou 2 miles....

Southwest Wessingtons near Ishams

Sec. 27, T. 108, R. 66. ..................

Sec.3,T.107, R. 69.... ................

Elevation above 

River 

outside.

310 

349 

100 

215 

275

260 

250 

290

310 

400 

160

100

400 

610 

605 

450 

575 

697 

800

215

Plain 

iiiside.

130 

225 

75 

90 

150

150 

100 

135 

65

160 

120 

260 

250

200

390 

260 

54 

175 

300 

275 

75 

50

300 

475 

200 

110

Sea.

1,550 

1,505 

1,325 

1,361 

1,421 

1,740 

1,450 

 1,440 

1,475 

a 1, 400 

a 1, 500 

1,615 

1,745 

1,800 

1,805 

1. 645 

' 1, 620 

 1,850 

1,845

1,865 

1,986 

2,090 

l,-975 

a 1,775 

1,820

1,954 

1,785 

1,765

Highest 

rocks 

near by.

18 

100

120 

150(?)

200

55 

50

100

a Estimated. 

STONINESS OF THE MORAINE AND DISTRIBUTION OF BOWLDERS.

The stoniness of the moraine seems to bear a direct relation to the 

action of water upon it. Where there are traces of torreatial wash in 

the configuration of the country there is usually an increase in the 

number of bowlders; for example, in the internal drainage of Turtle 

Eidge bowlders abound upon the abrupt sides of the channels. And 

yet this was evidently only one influence among several. The occur-
40 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

rence of bowlders in patches or nests, upon the moraine as well as 

upon the till, is probably due to some obscure segregating action of 

the glacier or of glacial streams.

The number of bowlders in general in the Dakota moraine is much 

less than in moraines farther east, as, for instance, in Wisconsin. This 

is to be explained largely by the absence of bowlder-forming rocks in 

the region. The glaciers over the whole Dakota lobe, with the exception of a few isolated square miles of Archean rocks, rested upon clay 

which was evidently easily eroded both by water and by ice. As has 

been already stated, the harder strata at the advent of the ice were, as 

a rule, found capping a few buttes. These buttes, in most cases, seem 

to have withstood the ice, and so their capping was not transported to 

any great distance.

Bowlders of crystalline rocks, granite, greenstone, quartzites of 

several sorts, and of a very fine-grained, compact white limestone 

from the upper Silurian beds, occur everywhere, with little variation 

in their relative prominence. Some of the variations noticed in the 

character and distribution of bowlders are as follows: Flesh-colored, 

fine-grained granite, black slate, and white and dark quartzites abound 

more along the western side of the Dakota lobe. The white and the 

yellow Silurian limestones were noticed in unusual size and profusion 

in Lake Andes Outlet and about the mouth of Choteau Creek, especially to the west of that stream. Bowlders from 8 to 10 feet long and 

from 2 to 3 feet thick are not uncommon, while smaller ones are much 

more frequent. Their abundance so impressed me that in several 

clusters and heaps I counted them.. In one, 16 out of 22 were limestone ] in another, 8 out of 16; in another, 40 out of 48. Several others 

showed more than half limestone. The clusters counted were all on 

the lower bowldery terrace.

There are several kinds of rocks found in southeastern South Dakota 

which are adapted to form erratics. One is a siliceous rock of Tertiary 

origin resembling buhrstone, of fine texture, yellowish color,and usually 

marked with the stems of plants. This has been noticed apparently 

near position a little south of the Northern Pacific Railway, and occasional bowlders, not often more than 6 inches in diameter, are distributed to all portions outside of the moraine, specimens being found, 

though never in considerable numbers, as far south and east as Page 

County, Iowa. A second rock is the greenish quartzite capping the 

buttes of the Bijou Hills system. This stone seems not to retain its 

hardness when exposed to the action of alkaline waters, for bowlders of 

this rock are rarely found far from their original position without showing much disintegration. The next two, from the Cretaceous, furnish 

bowlders, but they last for only a .short time and are found rarely at 

much distance from their original beds. They are the " chalkstone " and 

the Dakota sandstone. Under the influence of moisture and shearing 

stress one quickly changes to clay and the other to sand. Fossils from
TODD.] BOWLDERS OP THE OUTER MORAINE. 41

the one and pebbles from the other are not infrequently found. The 

largest bowlders from the Cretaceous, though rarely over a foot in 

diameter, are fragments of large bluish limestone concretions from 

the Ben ton, and usually show a septarian structure; they are not 

common, but seem quite durable. Interesting erratics, but rarely 

more than 4 inches in width, are derived from the Pierre and Benton. They are fragments of clay-ironstone concretions, which on 

weathering become hollow pebbles of limonite. The last is by far the 

most important. It is the well-known quartzite which exists in extensive ledges through southern Minnesota and westward as far as the 

vicinity of Mitchell. Its structure is favorable to the formation of 

bowlders, being naturally divided into blocks by numerous joints and 

seams of stratification. Furthermore, its indestructibility preserves 

the bowlders when passing through the ordeal of glacial and glacionataiit action. Eed quartzite bowlders are rarely over 5 feet in length. 

The most western point where this rock was exposed to the abrasion 

of the ice is at Eockport. Another point farther west is found on 

Enemy Creek, in sec. 20, T. 102, E. 59, but from its lower position seems 

never to have been eroded by the action of the ice.. The most western 

point in the moraine and the deposits outside at which red quartzite 

bowlders have been found is in a line nearly due south of Eockport, on 

How Creek, in northern Nebraska. It is not unlikely that an extended 

search in the Choteau Creek Hills may discover them there, but as yet 

none have been observed. From this point they increase rapidly in 

numbers toward the east. This distribution corresponds with the 

direction of the glacial scratches at Eockport and vicinity, which is 

southeast.

Another interesting point in the distribution of the red quartzite 

bowlders is that they are very abundant 70 to 90 per cent of all 

erratics in the north end of Turtle Eidge, southwest of Turtle Eidge 

Creek and east of Clay Creek, but outside (north and west) of those 

streams they are rare. This is so noticeable, that it has attracted the 

attention of the residents of the region. This corresponds with the 

distinction between the first and second moraines.
OHAPTEE III. 

THE DRIFT REGION OUTSIDE OF THE OUTER MORAINE.

The drift, by which we mean any deposit, whether bowlder-clay, 

sand, or gravel, containing erratics which show marks of ice action, 

extends for greatly varying distances outside of the moraine. As 

already stated, the erratics are mainly from the Archean and Silurian 

rocks. The region under consideration is naturally separated into the 

following divisions, which may be designated according to the portions 

of the moraine corresponding to their inner boundary.

What we shall; for convenience, style the Red Lake region, includes 

all territory lying outside of the moraine from Turtle Point and the 

moraine west to the vicinity of Pratt Creek, embracing 

The Ponca reach, extending from the mouth of Pratt Creek to the 

mouth of the Mobrara.

The loess region, extending on its northwestern border from the 

mouth of the Niobrara to Sioux Falls.

The Coteau des Prairies region, extending from Sioux Falls to Vermilion Point and beyond.

In each case the outer limit, as before stated, is the limit of the drift. 

Each region presents characters peculiar to itself. The first occupies 

an extensive external angle of the moraine and presents the peculiarity 

of driftless areas rising as islands above the sheet of investing drift. 

The second is long and quite narrow, being confined almost wholly to the 

present gorge of the Missouri. The third is covered with a continuous 

sheet of drift, and that again with a blanket of loam or loess. The 

fourth, like the first, occupies an extensive angle of the Missouri, but 

presents no driftless islands and is only partially covered with the 

loess.

RED LAKE REGION.

Topographically this region consists of a broad, basin-like widening 

of the more elevated or superficial portion of the valley of the Missouri, 

from the vicinity of the Great Bend to the vicinity of the Bijou Hills. 

It may be compared to a great lake bed in which wide, shallow channels have been eroded, and then at a later stage some of the principal 

ones have been narrowed and cut down to thrice their original depth.

The region is bounded on the north and east by the moraine. On 

the west its boundary may be given provisionally as follows: From the 

Missouri above the Great Bend along the west side of Medicine Creek

42
TODD.] RED LAKE DRIFT REGION. 43

to the vicinity of Medicine Butte; thence past Eed Butte south across 

White Biver; thence curving southeast to Waterholes Creek, 5 or 6 

miles above its mouth; thence along the eastern side of its abrupt 

valley to the Missouri, which it closely follows down to the mouth of 

Snake Creek. This boundary is mainly determined by the distribution of bowlders, which are sparsely scattered over the older deposits 

of the country.- The underlying rocks of the region are Pierre clays, 

which were evidently much eroded before the deposition of the drift. 

The Tertiary also is represented by quartzite, gravels, and probably 

some clays, capping the buttes along the southern and western border.

FIG. 12. Bijou Hills, from the north.

The bottom of the pre-Glacial basin, as indicated by the course of the 

streams as well as by direct observation, was in the vicinity of Chamberlain. Around the edge of the basin to the west and south are isolated buttes capped with a greenish Tertiary quartzite. A range of these 

begins with the Bijou Hills and extends in a nearly continuous range 

westward. (See figs. 12 and 13.) Similar buttes are found southwest 

of the Great Bend, one of the more conspicuous being Medicine Butte, 

about 16 miles west-northwest from Chamberlain.

The drift which covers this region varies in thickness from 20 to 80 

feet along the eastern side to merely scattered bowlders, as is usually

£ I* 

44' 41' iO' _______4°JS 4Z'

FIG. 13. Buttes south of White Kiver, from the north, v West end of Bijous. vv Gap of Waterholos

Creek.

the case, west of the Missouri. These become fewer and smaller to a 

scarcely determinable edge. On the east side of the Missouri, between 

it and the moraine, is a nearly continuous sheet of till, which, as elsewhere, is yellowish above and reddish or bluish below. The surface of 

this till is unlike that which is found inside of the moraine in that it 

combines the usual features of erosive topography with faint traces of 

such basins as are found within the moraine. The average height of 

hills above minor valleys is from 30 to 50 feet. The elevation of the 

broad swells or uplands above the principal valleys is from 125 to 200 

feet. Basins are rarely over 5 feet in depth and an acre in area. Moreover, many of these, by their position, suggest the idea that they are
44 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

due to the imperfect filling of old tributary valleys. They were noticed, 

especially along the northwest side of the Red Lake Valley, about 50 

feet above its bottom. The accumulation of an indistinct terrace below 

that level may be conceived to have filled the side valleys at the mouth 

more than farther back. The surface is rarely too rough for tillage, 

except in the banks of present streams. The higher portions are covered, west and north of Eed Lake, with 6 to 10 feet of yellow silt or 

loess. This hides bowlders, which are seldom seen except below 50 

feet above the bottom of Ked Lake Valley. In places there are traces 

of a terrace at about that height, as has been already stated, but bowlders are not confined to it, and are probably more noticeable below 

that level, because the loess has there been frequently removed. 

Everywhere there is a rich, black, loamy soil, except in basins and low 

flats, where " alkali" clay abounds.

To the general statement that the region between the Missouri and 

the moraine is covered with till, the following notable exceptions must 

be made: First, the region bounded on the north by a shallow valley 

running along the north line of Buffalo County from the Missouri to 

Boxelder Creek, thence along that stream on the east to its junction 

with Crow Creek, and thence by an undetermined line to a bend in the 

Missouri about 5 miles above Chamberlain. Over this region the drift 

is absent, except in the form of bowldery terraces along the principal 

streams, and elsewhere sparsely scattered bowlders, perhaps one to the 

square mile. The surface of this region presents gentle declivities, 

except close to larger streams, where the underlying clay has been 

excavated into yawning ravines. The deep unbroken valleys lie about 

100 feet below the broad rounded swells which separate them. The 

soil on the upland is a fertile, black, loamy clay. The sides of ravines 

are barren. The highest portions above Crow Creek are about 1,770 

feet above the sea, or 450 feet above the Missouri. The highest summit south of Crow Creek and one a few miles northwest of Chamberlain 

may be a few feet higher, but neither rises to the height of the till 

near Bijou Gap.

Another and more perfect exception is found in the western Bijou 

Hills, including the western end of the East Bijou, the West Bijou, 

the buttes which stand in the gorge of the Missouri, and the summit 

of a smaller hill northwest of Bijou Gap. Upon all these no drift, not 

even scattered bowlders or pebbles of drift origin, is found above the 

altitude of 1,885 feet, or 565 feet above the Missouri at Chamberlain.

The distribution of drift in the East Bijou is peculiar, and as it affords 

a contrast to the cases in hand, we will consider it more fully. The 

hill is a long, narrow butte, nearly 6 miles long and over a mile wide 

near its western end, and 300 feet in height. The eastern end is 

wrapped in a heavy covering of bowldery drift, as is all, except a sickleshaped spur about a mile in length and nearly equal in height to the 

rest of the hill, which extends northwest from the body of the hill and
TODD.] RED LAKE DRIFT REGION. 45

curves around toward the southwest. This spur, with a sharp southwest angle of the hill, incloses an amphitheater which opens to the 

southwest. The southwest angle of the hill is covered with bowlder 

clay upon its southern and western slopes to the depth of about 30 feet. 

The top of the northwest spur is wholly without drift, except on its 

outer slope. In the amphitheater bowlder clay rises to the l5S85-foot 

level in foothills which show a gentler slope than the hill itself. A 

conical hill lying a little detached from the north side of the hill is 

also driftless. The edge of the till on the flat summit of the hill ends 

in a slope to the northwest, its trend being northeast-southwest.

West of the Missouri only scattered bowlders are found remote from 

the immediate vicinity of the gorges of the Missouri and White rivers, 

except a gravel-topped plateau several miles in extent southwest of the 

mouth of White Biver and south of American Crow Creek, 3 or 4 miles 

from the Missouri. Masses of drift, both gravel and bowlders, are 

also found capping extensive terraces along both the Missouri and the 

White rivers from 200 to 250 feet above the present level. These will 

be more fully described in the chapter on terraces.

Along the south side of the old valley of White Biver, which is 2 

miles in width, and in which the present gorge is excavated to the 

depth of 200 feet, extends a very conspicuous elevated plain covered 

with gravel, estimated to be 2 or 3 miles wide and extending along 

White Biver at least 5 miles. It is much eroded by ravines. ' Its 

pebbles are mostly of western origin, as is indicated by the great number of glassy, white, dark, and black quartz, and fragments of chalcedony seams. Granites and white limestone and other northern 

bowlders are prominent on the sides of the ravines and scattered less 

frequently on the level surface. This plain lies about 350 feet above 

White Biver. Along the southern side of this plain lies a low swell, 

about 20 feet in height, on which there is a great profusion of bowlders 

of all sorts; 28 granite bowlders from 1£ to 4 feet in diameter were 

counted in going up the ridge, one being 6 by 4 feet. A little south, 

and about 25 feet nigher, blocks of Bijou quartzite are abundant, and 

Cretaceous clay occupies the eroded but gradually rising surface for 

4 or 5 miles farther south. At that point a cluster of flat-topped hills 

rises about 75 feet above the surrounding plain and about 550 above the 

Missouri. They are considerably eroded, as though they were only the 

remnant of a much more extensive gravelly plain. Their preservation 

may be partly due to the greater thickness of deposit at that point, 

but are more probably due to the fact that they lie on the summit of 

the watershed between White Biver and W'aterholes Creek. Their hills 

are capped with a deposit of western gravel 5 to 10 feet in thickness, 

resting on a drab-colored loam. Upon these hills were found a few 

bowlders, one a dark hornblendic gneiss 3 feet in diameter, another of 

gray granite, smaller. Upon the crest of the watershed southeast of 

these hills several other bowlders were found, but none to the south
46 MORAINES OP SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

or southeast, except two on the summit of a similar butte 3 or 4 miles 

southeast of the last-mentioned hills, which rise to the same level. 

Upon this were found a large bowlder of white limestone, about 5 feet 

long, and a smaller one of gray granite. Similar buttes farther south, 

rising from the valley of the Waterholes, showed abundant blocks of 

Tertiary quartzite, but few pebbles, and no traces of northern drift.

Excepting the cases already mentioned, no northern bowlders were 

found over the region south of White Eiver. Immediately east of these 

hills is the wild gorge of Waterholes, and west the shallower valley of a tributary of White Eiver. If traces of drift were formerly 

more abundant, as is possible, the great erosion connected with these 

valleys has removed them. The deposit along American Crow Creek 

is mostly on the south side, 24 miles from the Missouri. It closely 

resembles the extensive gravelly plain south of the White Eiver, before 

described. It lies at an altitude of about 350 feet above the Missouri. 

It is about a mile in width and dips slightly to the north and east. 

The region between the lower portion of Medicine Creek and the Missouri has not been closely examined, but from its general appearance from 

the top of Medicine Butte, and its elevation, it is unhesitatingly put 

down as belonging to the scattered bowlder region. In the valley of 

Medicine Creek, west of Medicine Butte, no trace of drift was found, 

but on the summit of the watershed, about 2 miles south of the peak, 

drift was noticed. A ride of a. dozen miles to the southeast disclosed 

none except in the close vicinity of American Crow Creek. The general level of the gently undulating plain occupying the whole region is 

from 450 to 500 feet above the Missouri.

ANCIENT CHANNELS.

As before stated, the region is traversed by broad valleys. These 

are found for the most part to coincide with present streams. Their 

elevation above the Missouri is from 200 to 300 feet. One valley extends 

from American Creek at Pukwana southwestward past lied Lake in, a 

direct line to the Missouri Eiver. This channel is from 1£ to 2 miles 

wide, and is occupied in its deepest portion by Eed Lake, a shallow 

body of water 4 miles long and 2 miles wide. It is named from the 

abundance of reddish weeds which appear along its shores and cover 

considerable of its surface in the latter part of summer. Just east of 

Pukwana, and extending for 5 or 6 miles up American Creek, is an 

ancient lake, which has been filled. The level surface, the eroded 

spurs, and the sand and gravel struck within a few feet of the surface 

leave no doubt concerning the fact.

The heads of these various valleys connect in several cases with gaps 

in the moraine. Crow Creek, 5 or 6 miles southwest of Waterbury, 

crosses the moraine, which is there attenuated and broken. The northern and larger branch of Smith Creek in a similar way crosses, just 

northwest of Crow Lake, the faintly developed loop of the moraine, which
TODD.] RED LAKE DRIFT REGION. 47

is pushed south down the west side of Turtle Ridge. The east branch 

connects with the internal drainage system of Turtle Eidge and the 

gap before described southeast of Crow Lake. Two of its southern 

tributaries rise near the moraine, one at the gap near White Lake and 

the other at a gap 5 miles northeast of Kimball. American Creek heads 

on the moraine near Kimball, and receives tributaries from the outer 

slope of the moraine farther west. Snake Creek beads near a gap or 

attenuated portion of the moraine south of the Bijou Hills. Another 

water course from the same stream extends north through Bijou Gap 

toward the lower part of the moraine, north of the East Bijou.

BOWLDER RIDGES.

A remarkable feature of these valleys in their upper course is the 

presence of numerous sharp bowldery ridges extending parallel with 

their course. These resemble those already described in connection 

with the gap near Crow Lake, and probably are of the same origin. 

They are from 5 to 15 or 20 feet in height, and frequently show a clustered arrangement. One system was noticed extending along the south 

side of the valley of Smith Creek near Lyonville. Another along the 

tributary valley from the vicinity of Kimball. Another, less conspicuous, was noticed along the American Creek Valley. In this case a tendency to a transverse arrangement was noticed. It is not unlikely these 

were formed in a different way.

OLD WATER LINE.

Another and still more remarkable feature, already alluded to, is a 

trace of water lines. This was first noticed in the vicinity of the West 

Bijou Hill. As one ascends its northern side the bowlders suddenly disappear at an apparently horizontal line. None are found upon the summit, nor anywhere upon the southern slope above that level. The drift 

masses on that side lie as low foothills between the higher spurs extending from the hill. Erosion has frequently made the line between the two 

very distinct. Upon the northern slope a line of more prominent foothills, or an eroded terrace, corresponding to this line, is quite distinctly 

shown. Around a high conical hill about 3 miles northwest of the gap 

the drift is found to disappear at about the same level. The border of 

the driftless region south of Crow Creek has not been examined with 

reference to this point. West of the Missouri the bowldery ridge, 

already mentioned as lying south of White Eiver, is presumably near 

the same level; the distance between the two localities renders an 

exact determination with the barometer impossible. Other features 

of the upland of this region are provisionally referred to the action of 

currents of water. In the channel passing through Bijou Gap, a little 

south of the gap, is a marsh covering several acres. Southeast of the 

gap separating the West Bijou from the Brick Kiln Buttes are three or 

four slight basins trending southeast. Trailing southeast from each
48 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

of the Brick Kiln Buttes, though now detached from them by circurndenudation, is a long southeast ridge. One of these, where studied, 

showed itself to be capped with loess-like silt, although its core is 

largely Cretaceous clay. Southeast of Medicine Butte is a shallow 

marshy basin covering perhaps 2 square miles, its longer axis points 

toward a sag in the low swell running east from the butte. South of 

this lake 3 or 4 miles are two much smaller marshy basins in a broad 

sag running southeast to the valley of American Crow Creek.

ELEVATIONS.

The elevation of the prominent points of the region, as given in the 

subjoined table, will furnish a more accurate idea of its topography:

Elevations in the Bed Lake region. 

[All are barometric except those marked r, which are derived from railroad levels.]

Locality.

Summit of drift terrace in the Bend , ................

Summit between Missouri and Boxelder, 10 miles

Boxelder Creek east-northeast. ................ .....

Summit of moraine northeast .......................

Summits 11 and 16 miles east .......................

Valley of Elm Creek between .......................

Boxelder Creek ...,. ........................ ........

Medicine Butte.. .... ...............................

Lake southeast .....................................

Plain east, average level.... ........................

Bluffs west of Chamberlain .........................

Gravelly terrace between Smith and Crow creeks.... 

Summit 5 miles northeast of Pukwana ..............

Above the 

Missouri.

Feet.

235

3-10

425

255

372

435

320

420

285

210

335

425

875

400

430

325

325

460

230 

380

216

210

Above the 

sea.

Feet. 

1,334

1,590

1,695

1,780

1,610

1,725

1,790

1,341

1,660

1,760

1,625

1,550

1,676

1,765

2,100

1,725

1,750

1,645

rl,321

1,645

1,780

1,550 

1,700

1,537

1, 530
TODD.] RED LAKE DRIFT REGION.

Elevations in the Red Lake region Continued.

49

Locality.

Kimball................ ............................

Moraine near Kimball ..............................

Moraine southeast of Red Lake .....................

Gravel-topped buttes 5 or 6 miles southwest of mouth

«/ o

Gravelly plain south of old valley of White River. .. 

Terrace of White River 6 or 8 miles above its mouth,

Missouri at mouth of White River ..................

High hill south of the junction of Red Lake Outlet

Moraine north of East Bijou .....................

Larger Brick Kiln Butte ...........................

Above the 

Missouri;

Feet.

204

458

500

325

570

510

360 

| 225

300

460

620

470

500

450

710

600

690

460

590

710

Above the 

sea.

Feet. 

r 1,525

r 1, 779

1, 820

1,645

1,880

1,800

1,665 

r 1,545- 

\ 1, 500

1,308

1, 610

1,765

1,930

1,775

1,790

1,740

1 290

2,000

1,890

1,980

1,749

1, 880

2,000

NOTES FROM WELLS AND OTHER EXPOSURES IN THE RED LAKE

' REGION.

Natural exposures displaying the drift are almost entirely wanting. 

Burrows'of badgers and pouched-rats not infrequently display the subsoil, but no more. Wells, the only artificial excavations available, 

rarely pierce through the drift, and are generally so curbed as to afford 

no opportunity for direct examination. The statements of well-diggers 

and other reliable persons who were present when the well was dug, 

with illustrative material around the mouth of the well, have been necessarily the main reliance in most of the cases tabulated below. Bed 

Lake is given as a base of reference. Steep banks, mostly grassed 

over, have supplied a little information, which is in general valuable, 

but not exact.

Bull. 158 4
50 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

Data from wells and other exposures in the Bed Lake region. 

[These data were collected before 1888. There has been no opportunity to tabulate later data.]

Locality.

Bottom of ravine, 4

miles west of Pukwana.

Three miles west of

Pnkwana.

A few rods southwest

of last, in a basin.

Pukwana, on terrace

of an old lake.

Three m iles northwest

of Red Lake, edge of

basin.

Three miles west of

Red Lake.

One mile south of

south end of Red

Lake. 

Another near by ......

A little west of last. . .

On flat southeast of

Red Lake.

Five miles southsouthwest of Red

Lake.

One-half mile east of

last, in a basin .

Five miles north of

West Bijou.

Eighty rods north of

West Bijou, on knoll.

A mile west of southwest angle of East

Bijou, on a ridge.

At foot of southwest

angle of East Bijou.

Elevation 

above 

Ked 

Lake.

Feet.

45

105

100

10

75

85

40

40

40

15

160

160

215

270

235

210

-

Description.

20 feet deep; 6 feet in "soapstone."

75 feet yellow till above, the rest bine

pebbly clay ; 1 foot water.

17 feet; plenty of water.

12 feet yellow till above, 3 feet water;

abundant water.

3 feet black soil, 8 feet yellow till, limestone and other pebbles, blue till in the

bottom.

60 feet through yellow till and gravel,

"no blue clay;" good water.

16 feet soil, yellow till and sand, 24 feet

blue till ; no water.

16 feet yellow till and sand, 20 feet blue

till; no water,

14 feet soil, yellow till and sand, blue till

touched ; plenty of water.

3 to 4 feet soil, 25 feet yellowish and reddish pebble clay, and sand below.

A few feet yellow loamy till ; pebbles not

very numerous.

Large pile of reddish-gray pebbly clay

thrown out.

5 to 6 feet "old soil," 6 to 7 feet yellowish

silt with calcareous concretions.

6 feet yellow till, little soil (a cellar).

40 feet soil, then yellow pebble clay, then

sand, then bluish dirt which grew harder,

52 feet soapstone.

40 feet loose clay.
TODD.] RED LAKE DRIFT REGION.

Data from wells and oilier exposures in the Eed Lalce region Continued.

51

Locality.

Two and one-naif

miles southwest of

southwest angle of

East Bijou.

Sec. 28, 4 miles south

of East Bijou, southwest slope of high

hill.

Sec. 28, west center . ...

Sec. 28, southeast corner, in a ravine.

South of west end of

West Bijou.

Bluff 1 mile northeast

of Chamberlain.

Bluffs east of Chamberlain.

Bluffs 2 miles south of

Chamberlain.

. Bluffs south of Eed 

Lake Outlet.

Elevation 

above 

Eed 

Lake.

Feet.

180

280

245

230

225

85

115

145

240

Description.

Struck blue clay (Cretaceous) at 28 feet.

All bluish clay.

30 feet yellow till, 25 feet soapstone ; little

water.

16 feet yellow clay, a little water, 15 feet

blue pebble clay, 4 feet "black soil,"

'' soapstone."

38 feet yellow pebble clay above, "black

clay" below, then 2 feet of "soapstone."

60 feet drift.

5 to 10 feet loess, 70 to 75 feet drift, a reddish cheeky clay 50 feet below top.

5 feet soil and loess, 1-J- feet" yellow and

drab dirty sand, 40 feet pebbly clay,

quite gravelly, above drab clay. 

20 feet drift above, yellow, loamy, bowldery clay below, a gravel bed, bowlderets, 50 per cent Bijou quartzite, 25

per cent white limestone, some bowlders

2J feet thick.

EXPLANATORY HYPOTHESES.

Such are the general facts derived from a study of the region, and 

we naturally look for some hypothesis by which they may be explained. 

There are but two which present themselves. One is that this region 

at least so much of it as is now covered with till at some time previous 

to the formation of the moraine was covered by the ice sheet, which 

was either too thin or occupied the region too short a time to obliterate 

the pre-GHacial topography. The other hypothesis is that the dispersion 

of drift was accomplished by floating ice in an expansion of the Missouri, covering the region contemporaneously with the occupation of 

the moraine.
52 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

In favor of the first theory it may be urged that till is believed by 

many to be an ancient ground moraine; also that the occurrence of 

basins and bowldery ridges resembling those of glaciated areas can not 

be otherwise explained. Furthermore, topographical conditions seena 

somewhat favorable for the extension of a lobe westward between White 

Lake and the Bijou Hills, and such corresponds well with the observed 

distribution of till.

Against this hypothesis the following considerations may be urged:

First. If we make the extension of the ice correspond to the present 

distribution of till we must suppose such an extension both north and 

south of the Bijou Hills by an ice sheet, which, at least around the 

West Bijou, could not have been more than 100 feet in thickness, and 

extending on that level at least 3 miles around the East Bijou, while in 

less than 40 rods it must have risen from 100 feet to considerably over 

300 feet in thickness. Or, if we postulate first a thin ice sheet of greater 

extent, and later a much thicker one of less extent, we find no adequate 

room for the drainage during the occupancy by the second ice sheet.

Second. Such an extension must have passed more than 15 miles 

beyond the moraine about Eed Lake, while in the northern portion of 

the region it extended in some places less than 2 miles. Such difference in fluctuation at nearly or quite equal altitudes is incomprehensible.

Third. This hypothesis fails to offer a rational explanation for the 

scattered bowlders which cover by far the greater portion of the region 

under consideration.

Accepting therefore provisionally the other hypothesis, we may explain the facts discovered as follows: During the first advance of the 

ice sheet streams to the north and west of this region, finding their 

courses checked to the east, may have escaped around the edge of 

the ice; at first around north of the Wessington Hills; later down east 

of the Eee Hills southeast to White Lake; still later from the Great 

Bend to the White Eiver and north of the Bijou Hills. Or, if we 

assume that the Missouri in this region dates back to pre-Glacial times, 

we may forego these suppositions. But finally the ice reached the 

Bijou Hills and soon after its greatest extent to the mouth of Pratt 

Creek. At this stage the water over' the Eed Lake region rose to its 

highest level, deposited the scattered blocks everywhere, and began 

the accumulation of till along the southeast side of the basin. The 

influx from the White Eiver formed the highest gravel terrace, which 

was probably rendered the more easy by the derivation of material 

from the conglomerate strata of the buttes near by. The till filled to 

the water level in the vicinity of Bijou Hills. The accumulation of the 

till in this portion, rather than elsewhere, may be accounted for by the 

occurrence of gaps through the moraine at that time, of course, larger 

than later north of Kimball and north of the Bijous. The ice lobe of 

the Eee Valley may not have attained its maximum extension at this 

stage because of the greater elevation of its bed.
TODD.] PONCA REACH DRIFT REGION. - 53

The outlet of this basin through the Bijous and around the ice at 

Pratt Creek probably soon cut down to the 350-foot level by the deepening of the channel west of the Bijous. The till continued to form in 

the southeast portion. The lower gravelly terrace south of White 

Eiver was formed, as also the accumulation south of American Crow 

Creek. The Eee lobe with its branches had meanwhile reached its 

position, and the high bowldery terraces along the Missouri at the 

Great Bend and along Boxelder Creek were forming, and the upper 

portions of other important streams of the region were outlined. The 

formation of some of the osar-like ridges in these valleys are possibly 

to be referred to this stage.

During the thinning of the ice sheet these streams became unusually 

laden with silt, while ice blocks became rare, because of the stagnation 

of the ice, and a thin mantle of silt overspread the region below this 

level. As the melting of the ice sheet continued in its recession to the 

position of the second moraine, the channels were gradually deepened 

to about the 200-foot level. Most of the osar-like ridges were formed, 

and faint bowldery terraces of the Ked Lake channel, which may be 

referred to a reassortment of local material rather than to that directly 

derived from the ice sheet.

More space has been given to this region because of its unusually 

clear bearing on the questions connected with glacial and glacio-natant 

action, which will be further considered in connection with the loess 

region, where the phenomena are more complicated.

PONCA REACH.-OR REGION FROM MOUTH OF PRATT CREEK TO 

MOUTH OF NIOBRARA.

This region presents striking contrast with the last. It is narrow 

and straight. Its outer margin at no point is more than 3 or 4 miles 

from the river, nor more than 15 miles from the inside of the moraine. 

Its southwestern limit ends very abruptly along the edge of a high tableland corresponding geologically with the Bijou Hills, and rising abruptly 

450 to 600 feet above the Missouri. The Missouri, from Pratt Creek to 

Fort Eandall, lies in a. narrow gorge, from 2 to 3 miles wide most of the 

way, with a high bowldery terrace along its left bank, at an elevation 

of 175 to 250 feet. Lower alluvial terraces are scantily developed. On 

the right bank the frowning edge of the table-land before mentioned 

rises abruptly from the river, except in the bend above the mouth of 

Whetstone Creek, where the bowldery terrace is finely developed, and 

at Fort Eandall, where a high alluvial terrace is found.

Viewing the bluffs south of Pratt Creek Gap from about 12 or 15 

miles north, they appear rising above the glaciated plain to about the 

same height as the Cedar Creek Hills to the left, which are, as before 

stated, a portion of the moraine; and they are at a lower altitude than 

the ancient water level in the vicinity of the Bijou Hills. From both
54 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

considerations it would seem impossible, under the lacustrine hypothesis, that they should not at some time have been more or less covered 

with drift; nevertheless, no drift is now found upon them, and not even 

in the valley of Whetstone Creek did a considerable search reveal any 

bowlders or northern gravel. This is the more remarkable because the 

surface of the country drains southward into Whetstone Creek from the 

crest of the bluffs overlooking the Missouri Eiver on the north.

The southwest side of the river was examined again near Fort Eandall, and nothing was found higher than about 425 feet above the river 

which could in any wise be considered of northern origin except a very 

few scattered pebbles. The examination was continued for 15 miles, to 

the summit of the divide between the Missouri Eiver and Ponca Creek, 

600 feet above the former. Much of the surface traversed was about 

450 feet above the river, and was crossed with shallow valleys extending 

from the northwest to the southeast. The surface was a dark loam, but 

the subsoil everywhere showed either the clays of the Cretaceous or, 

upon the high hills, the sands, marls, and gravel of the Tertiary.

From the vicinity of Fort Randall to the mouth of Choteau Creek the 

moraine is more remote from the river. Its outer slope, which shows 

the usual billowy appearance of hills, is ravined by two or three considerable brooks, which rise near the crest of the moraine and run 

nearly directly south to the river. Their upper tributaries occupy a 

more or less denned valley just outside of the moraine and parallel with 

it. This slope extends down to the high terrace before mentioned, 

which is here from 1 to 4 miles wide. This terrace shows a very even 

surface, sloping from a height of 250 feet at its outer side to about 200 

feet along its inner edge. An interesting feature appears about 5 miles 

northeast of Yankton Agency, where the northern edge of the terrace is 

marked by an abrupt bank, facing southwest aud extending for a mile 

or two. It is over 75 feet in height. Where the terrace was observed 

in the vicinity of Greenwood, near a stream, it was 130 feet above the 

river. There it is capped with 10 to 15 feet of silt, below which it is very 

gravelly and contains bowlders for a dozen feet or so. Lower down it 

presents the usual features of till. About 4 miles west of Choteau Creek 

its edge is 200 feet above the river. Its surface is free from bowlders 

and pebbles, being generally covered with a deep layer of silt. Below 

this a layer of 30 to 40 feet of loose yellow and reddish till prevails. 

Farther east, where its surface is ravined and cut into knobs, a wonderful profusion of limestone bowlders is found.

Upon the south side of the river the table-land before mentioned 

retains its altitude and terminates on the northeast sharply with the 

top of the river bluffs. It continues with scarcely diminished height 

to the mouth of the Mobrara, where it terminates abruptly.

Along this portion of the river a very narrow terrace hanging to the 

abrupt south bank, as seen from a distance, was judged to correspond 

to that on the north side. From the mouth of Choteau Creek to the
TODD.] PONCA EEACH DRIFT REGION. 55

month of the Mobrara the ice sheet seems to have abutted closely 

upon the river, much as at the mouth of Pratt Creek, but without 

pushing its moraine entirely into it, as it did a little farther east, in 

Emanuel Creek Gap.

Across the river is the eastern end of the southwestern table-land, 

rising abruptly from the junction of the Mobrara with the Missouri to 

the height of a little more than 300 feet. At this point it is a narrow, 

much-eroded ridge, but within 2 miles it attains an elevation of 400 

feet and becomes a table-land more than 2 miles in breadth, which continues toward the west, both rising and broadening. Its slope is pronouncedly northward toward Ponca Creek. It is traversed by deep, 

narrow valleys running in that direction from the very edge of the 

bluffs overlooking the Mobrara. These bluffs are sometimes even lower 

at the head of the valleys, as though the escarpment on the south had 

moved northward since the valleys were formed. About 6 miles west 

of the mouth of the Mobrara heavy deposits of western gravel were 

found in knolls along the crest of the bluffs, about 425 feet above the 

level of the river at Mobrara. These are so left by erosion as to stand 

out conspicuously above the surrounding surface. A trip was taken 

along the line of the trail to a conical butte rising about 60 feet above 

the general slope around it and about 500 feet above the river. Upon 

it? and at several other points, numerous large blocks of Bijou quartzite 

are found, but not the first trace of either bowlders or pebbles of northern origin are seen upon the general level of the highland. Both, however, are found scattered in considerable numbers over the spur at the 

eastern end to the height of 350 feet. It is a noticeable fact that they 

occur at the higher levels only in the sags upon the crest, where erosion would be least likely to remove them. They are very rarely found 

on the slopes of the bluffs or upon the flat at their foot. The limit of 

the drift at this point is estimated to be not more than 4 miles from the 

inner border of the moraine where it is developed on the opposite side of 

the river. The ice sheet must have been much nearer at its maximum, 

and when we remember that all the drainage of the vast western edge 

of the ice sheet must have passed this point, we are forced to inquire 

why the stream did not erode its way farther south; why it did 

not rise in its flooded stage so as to carry the bowlders (for there 

must have been some river ice, bearing drift, in glacial ice blocks) to a 

much higher level, to at least 450 feet, the level of blocks less than 4 

miles southeast. It is clear that either this table-land was above the 

level at that time, so that they could not be deposited, or, if deposited 

at a lower level, erosion has been sufficient to wholly remove them.

The before-mentioned gravel beds along the Mobrara evidently correspond in elevation to the extensive sheet of gravel south of the town 

of Mobrara. From a distant view it is j udged that these beds were connected through gravelly (?) knolls in the sharp bend of the Mobrara a 

few miles above its mouth.
56 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

LOESS REGION. 

BOUNDARIES AND SURFACE.

Although the word loess may suggest the whole area covered by that 

deposit, the boundaries of that region are so vague that we adhere to 

our original plan of limiting our description chiefly to the surface covered with drift. We therefore turn our attention first to the 

WESTERN BOUNDARY OF GLACIAL DRIFT.

This also has been less accurately determined in this region than in 

the preceding. The principal difficulties met in an attempt to determine it are as follows:

1. The deep and almost universal covering of loess, which extends 

much farther westward.

2. The gradual passage of the northern or glacial drift into a western or fluvial drift, which has been found to occur along the principal 

streams from the west. The distinctions which have been relied upon 

in the determination of the former have been the occurrence of erratics 

of red quartzite and white and yellow Silurian limestones; also the 

striation and abrasion of pebbles peculiar to glacial drift. On the 

other hand, the western drift presents lithological characters similar to 

those which have been previously recognized in the discussion of the 

Eed Lake region, and the pebbles are only waterworn.

3. The covering of the northern drift by the western. This may lead 

to wrong conclusions where exposures are incomplete.

4. The erosion and removal of the drift itself underneath the loess. 

This renders the upper surface of the drift very uneven, and because 

no drift is found upon the surface of a hillside one may fancy that none 

is present, where an exposure may reveal it as not only present, but 

rising high in the center of the hill.

So far as yet determined the western limit may be stated as follows: 

From the junction of the Verdigris with the Niobrara southeast, passing a mile or so east of Creighton, 5 or 6 miles east of Plainview, and 

east of Pierce to the vicinity of Norfolk; thence south along the western line of Stanton County, swinging to the east in Colfax County to 

the vicinity of Richland; thence in the same direction, passing 3 or 

4 miles east of David City, south along the east side of Plum Creek to 

the vicinity of Seward; thence south and southwest, passing west of 

Norval post-office to the vicinity of Friend; thence southwest indefinitely. That one may estimate as justly as possible the value of this 

determination the subjoined data are given.

1. Localities visited which are beyond the drift, with a few others 

reliably reported:

(a) No drift is found anywhere west of the Verdigris 1 nor between

1 Later investigation has developed the occurrence of a few syenitic bowlders upon the high terrace 

near Verdigris Valley, 180 feet above the stream.
TODD.] - LOESS REGION. 57

the Yerdigris and Bazile south of Sparta post-office. The Tertiary and 

Cretaceous rocks appear in that region in several places below the loess 

without the drift intervening, (b) On the south side of the valley, 

at Plainview, a bed of western gravel several feet in thickness was 

observed, but not the slightest trace of northern erratics. None have 

been found after a persistent search upon uplands for several miles west 

and north of that town, (c) The Yellowbank, north of Battle Creek, 

exposes a straight section 120 feet high, in which GO feet of fine sand 

rests on the horizontal surface of 60 feet of compact drab-colored clay; 

no fossils or pebbles in either. On a side hill, a little northeast, considerable western gravel was found, but no northern erratics, (d) From 

Norfolk to Columbus no drift was noticed in passing on the cars and 

none learned of by inquiry, (e) On a high steep hill facing Shell Creek, 

near Platte Center, numerous pebbles and a few bowlderets were found 

resting on Tertiary clays. None were of distinct northern origin j none 

were striated, and most have a decidedly western character. (/) In 

numerous deep cuts north of David City and in the south side of the 

Platte Valley no pebbles of any sort were found, (g) Four miles south 

of David City a recently bored 80-foot well showed only a few western 

waterworn pebbles in a yellow clay. (Ji) The unanimous testimony of 

well diggers is that west of Plum Creek, which runs south from near 

Brainard to Seward, uo "hard heads" or pebbly clay are struck in 

wells, though they arc uniformly much deeper than those east of that 

line. In both regions the deposits are similar down to what is commonly called the " old soil." Below that point those west of the Hue 

indicated show sand only, while those east exhibit bowldery clay. 

(i) Nothing but western gravel was found in the vicinity of York, and 

general testimony is to the effect that no u hard heads" or pebbly clay 

are found west of Seward.

2. On the other hand, in the following localities the glacial drift has 

been directly observed. A few others of which reliable information was 

obtained are added, but carefully distinguished.

An extensive sheet of gravel was observed south of Niobrara. A 

thin deposit begins a mile east of Creighton. There are numerous 

exposures of yellow till from Osmond east for 5 or 6 miles, and there 

is abundant pebbly clay with bowlders at the insane asylum 1£ miles 

northeast of Norfolk. "Hard heads" are reported as abundant 3 or A 

miles east of Pierce. Yellow and blue till with northern bowlders was 

found on Maple Creek in the northern part of Colfax County. Eed 

quartzite pebbles were found in quantity 5 miles northwest of Schuyler. 

Northern bowlders and pebbles are abundant on the bluffs south of Linwood, and less prominent about the head of Bone Creek 5 miles east of 

David City, also south of Brainard in Butler County. Bowlders abound 

on hillsides and in ravines generally east of Plum Creek and of the Big 

Blue in Seward County. Drift is shown several feet in thickness in a 

high bank on the Big Blue 9 miles southwest of Milford. Eed quartzite
58 MORAINES OF SOUTHEASTEEN SOUTH DAKOTA. [BULL. 158.

bowlders and other traces of glacial drift were observed in abundance 

south of Pleasant Hill in Saline County, and are reported in the vicinity 

of Fairbury, Jefferson County.

EASTERN BOUNDARY OF GLACIAL DRIFT.

Theoretically the eastern boundary of this region should coincide 

with the extension in that direction of drift material which has been 

dispersed by ice of the Dakota lobe either as a glacier or as icebergs. 

On either supposition a mingling of material with that which was dispersed from the Iowa lobe would be unavoidable; consequently there 

would be more or less drift from the northeast in the area under consideration. So far as is known, no lithological distinction which would 

be decisive in this case can be drawn. Bed quartzite and white limestone erratics are found inside both the Dakota and the Iowa loops of 

the moraine. The rock most likely to be of service in this respect is that 

from the Missouri Coteau, which resembles buhrstone, 1 but it occurs in 

such small fragments, and .so rarely, that-it must be of little service. 

The phenomena of most practical value which .are likely to be found 

are striae upon the underlying rocks, which show motion from a westerly 

direction. Topographical relations may also have some weight. So 

far as is known no such striae are found in this region east of the 

immediate valley of the Missouri. Farther north, however, striae are 

found in such relation to the Dakota loop of the moraine as will warrant 

us in placing the boundary which we seek far east of the Missouri. In 

Minnesota striae from the northwest, or even from more nearly west, 

are found at Pipestone, also at a point 7 miles south of Pipestone, 

according to Mr. Warren Upham of the Minnesota survey. Numerous 

striae have been observed also north of Valley Springs, South Dakota, 

from N. 62o w.

This gives us reason for locating, provisionally, the eastern boundary 

quite remote from the Missouri. It may nearly coincide with the 

eastern boundary of the loess deposit as given in a later section. A 

small bowlder resembling burhstone was found at Cherokee, on the 

Little Sioux, and another east of Shenandoah in Page County, Iowa, 

and it is not improbable that the eastern boundary should nowhere be 

nearer to the Missouri Eiver than 30 miles.

As before stated, the southern boundary is arbitrarily set at about 

100 miles from the moraine. The southern limit of the drift would lead 

us beyond the scope of this paper.

DESCRIPTION OF SURFACE.

Elevation. The surface of this region is considerably higher than 

that within the moraine; south of Emanuel Creek Gap the difference is 

about 250 feet, and east of Big Sioux Gap 150 feet. Along its western

1 This has been determined to be of Miocene age and formed apparently in marshes bordering the' 

lakes of that epoch.
ELEVATIONS IN THE LOESS REGION. 59

side the average altitude of the highest points is nearly 1,700 feet, while 

along the Missouri it is about 1,400 feet. The whole region slopes toward 

the south and east. This is shown by the following list of elevations. 

They are mostly barometric, but closely connected with points determined by railroad levels. Only such points are taken as lie in the 

general level of the country.

List of elevations in the loess region.

From north to south: Feet.

Bluffs south of Herrick, Nebraska....................................... 1,750

Hills north of Plaiuvie w................................................ 1,825

Hills near Battle Creek.................................................. 1,816

Plain south of Humphrey............................................... 1,690

Plain atOsceola......................................................... 1,680

Plain at York.......................................... ................. 1,662

Plain at Fairmont ...................................................... 1,656

Bluffs at St. Helena, over ............................................... 1,400

Summit of the divide southwest of Hartington.......................... 1,710

Hilltops southwest of Coleridge......................................... 1,840

Summit southwest of Northside......................................... 1,830

Summit 8 miles south of Stanton........................................ 1,800

Bluffs 5 miles northwest of Schuyler . .................................. 1,610

Plain at David City..................................................... 1,619

Higher knolls................ ........................................... 1,650

Plain at Germantown ................................................... 1,584

Plain at Dorchester..................................................... 1,501

Hills west of Ponca...'.................................................. 1,375

Hills west of Emerson .................................................. 1,630

Hillseastof West Point................................ ................ 1,526

South of North Bend.................................................... 1,450

Hilltops near Wahoo, over............................................... 1,300

Plain at Cheney........................................................ 1,435

Knolls at Cheney................................;...................... 1,460

Southeast of Valley Springs ............................................ 1,510

Plain at Warren, Iowa .................................................. 1,465

Hill east of Akron...................................................... 1,415

Hilltops south of Blair, Nebraska ........................................ 1,350

South of Louisville............................ ......................... 1,225

Near Turlington .......................... ................ .............. 1,195

From east to west:

Bluffs near Platte Center ............................................... 1, 645

Bluffs near Schuyler .................................................... 1,610

Summit near Maple ville................................................. 1,432

Summit west of Kenuard................................................ 1,285

Hills west of Calhoun............................................. ...... 1, 250

Guthrie, Iowa........................................................... 1,290

Plain at Friend, Nebraska............................................... 1,575

Knolls at Friend, Nebraska...... ........................................ 1,600

Plain at Dorchester ..................................................... 1,500

Hilltops northeast of Crete.............................................. 1,450

Cheney, general level .........................i......................... 1,435

Cheney knolls.......................................................... 1,460
60 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

It may be conceived that at least the western portion of the region 

was at one time a nearly level plain, out of which the valleys of the 

present streams have been excavated. The original surface of the 

plain has been quite perfectly preserved away from the larger streams. 

Between thePlatte aud the Elkhorn this is true as far east as the headwaters of Maple Creek. South of the Platte the plain extends as far 

east as David City and the Big Blue. Traces of the plain, in the form 

of high flat-topped hills, are found as far east as the Missouri and 

beyond; but the whole region was probably never filled to a level plain. 

Several things seem to indicate that when the region was first vacated 

by the depositing waters it was not a completely filled basin. We 

would not assume to decide between a lacustrine or flu vial deposition; 

probably both played a part. We proceed to give some of these because 

they also illustrate the peculiarities of the present surface.

Basin's and knolls. Even when the surface is most nearly a perfect 

plain, as in the region west of the Big Blue, there are shallow basins 

with clayey bottoms and corresponding swells. Along south of the 

Platte about Osceola the same is true, aud farther eastward about 

David City both features are upon a grander scale. Some of the basins 

are more than a mile in breadth and the knolls and ridges from 25 to 

40 feet. The aspect suggests the former extension of a shallow lake in 

which there were low islands or bars. Farther north, about the headwaters of Logan Creek, similar features, though much modified by erosion, are noticed in the topography, but erosion has cut down the 

basins, leaving the hills much more elevated, though still showing the 

same isolated and irregular arrangement. Doubtless winds have had 

a mild dune effect upon the loess.

Elevated ridges. In the northern part of the region under consideration a conspicuous feature of the topography are the high, somewhat 

discontinuous northwest-southeast ridges. One extends from near the 

mouth of the Verdigris to the vicinity of Bazile Mills. Another begins 

east of Santee Agency with a lofty spur running out several miles from 

the northern edge of the table-land north. It extends down into the 

southeast corner of Knox County. Another begins southeast of Yankton and extends southeastward to the West .Bow. Another begins 

near St. James and extends southeast into Dixon County, and possibly 

into the Winnebago Eeservaton.

These ridges are more narrow aud conspicuous toward the north, 

and may possibly be looked upon as the high watershed separating the 

intervening streams. Their surface features are doubtless due to 

erosion, but the prevalence of this direction remains unexplained. We 

must look for it in some peculiarity in the original surface where the 

courses of the present streams were begun.

In the list of elevations given, the summits of these ridges were 

taken rather than of lower surfaces between.

Ancient channels. This directs our attention to another problematic
TODD.] ANCIENT CHANNELS OF THE LOESS REGION. 61

feature. This embraces certain channel-like valleys which are found 

in northern Nebraska crossing the divide between the tributaries of 

the Missouri which run in a northerly direction and those which have 

a southerly direction. Their characteristics are best preserved upon 

the watersheds, because there they are least modified by erosion. 

The ope passing near Coleridge, Nebraska, may be taken as a type of 

the whole. It connects Bow Creek with the upper waters of Middle 

Creek, a branch of the Logan. It is a valley from 3 to 4 miles in 

width, showing two or three subordinate channels or intervales running approximately parallel with one another and depressed from 

30 to 50 feet below the broad, flat ridges between them, which at one 

time may have been bars or islands in the ancient stream. These terrace-like ridges are covered with a thin layer of loess, under which is 

found gravelly clay 20 or 30 feet higher than the channels. In the 

bottom of the channels, after penetrating the soil, which is deep and 

rich, sand of indefinite depth is struck. Coleridge, which occupies the 

summit of this channel upon the divide, has an altitude, according 

to railroad levels, of 1,672 feet. The altitude of a high loess ridge 

southwest of Coleridge is 1,800 feet, and a similar ridge 5 miles east of 

Coleridge is about 1,825 feet high. Northwestward from Hartirigton 

the general surface is much eroded and distinct traces of the channel 

are not found. However, there is nothing to forbid the opinion that 

the channel formerly extended in that direction.1

A similar channel passes from the Yerdigris to the Bazile at Creighton, thence southeast up the latter stream to Plainview, where it is 1£ 

miles in width, and does not present the complex appearance which 

was noticed at Coleridge. From this point it continues in a direct 

southeasterly direction to the north branch of the Elkhorn at Pierce.

A smaller valley, which passes from the east branch of the Bazile at 

Kemma southeast to the north branch of the Elkhoru, presents similar 

characters. These channels in Nebraska are all much eroded toward 

the northern end by existing streams.

Areas sloping away from principal streams. Another character of the 

topography, which is unlike that usually found in the chance arrangement of streams upon an even plain surface, is the frequent occurrence 

of drainage from the immediate vicinity of the principal streams to 

some subordinate stream. This is remarkably true along the southern 

side of the Platte Valley. For nearly 100 miles the waters falling immediately south of the edge of the bluffs, instead of making their way 

into the Platte, are carried away southward into the tributaries of the 

Big Blue. Even where small streams turn northward, as Bone Creek 

and Skull Creek, the bluffs rise precipitously next to the Platte Valley, 

and the waters, which eventually flow north ward, are first turned south1 Since the ahove was written, facts and considerations presented hy Gilbert, Bain, TJdden, and 

others have led the writer to give greater prominence to wind action in explaining the irregularities 

of surface mentioned.
62 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

ward through the narrow valleys of these creeks. So with the Elkhorn 

on its southern side from the vicinity of Wisner to Scribner, the land 

slopes from the very top of the bluffs southward and southwestward. 

Along the northern side the same feature prevails. Such subordinate 

streams as Plum Creek, Cuming Creek east of West Point, Bell Creek, 

and the west branch of the Papillion, draw, from the very summit of 

the bluffs along the Blkhorn. The same feature may be occasionally 

found along the present valley of the Missouri, but its greater depression and the probably less original elevation of its bluffs render it less 

prevalent and less evident. On a grander scale the whole of the northeastern corner of Nebraska may be instanced as an example of this 

feature, sloping, as it does, away from the eastward-flowing portion of 

the Missouri. Along the east branch of the Big Sioux, from the northern line of Iowa southward, a similar relation carries the waters from 

its near vicinity into Eock Eiver.

All of these features, when traced back to their beginning, point 

toward inequalities in their original surface of greater or less magnitude. 

Further reasons for believing that this original surface was uneven will 

be found in the section treating of the relations of the loess to the drift.

Principal streams. rThe central stream is the Missouri. Its valley 

north of Yaukton resembles in every respect that in the regions already 

described, but east of Yanktoii it puts on quite a different appearance. While its bluffs are still high along the south side, they show 

no older formation except near their bases. The valley suddenly widens 

to a breadth of from 8 to 10 miles. This breadth it retains to the 

mouth of the Big Sioux, where it is somewhat increased. South of 

Sioux City it attains a breadth in places of more than 15 miles. At 

Blair the valley begins to narrow, and near Rockport, southeast of 

Calhouri, it is about 3 miles wide. It is a significant fact that at this 

point the Carboniferous limestone begins to appear near the water level. 

Farther south the valley is very rarely more than 5 miles wide, and 

while the slope of the stream from Sioux City to this point has been about 

6 inches per mile it now increases to 1 foot per mile, which it continues 

to the southern line of Iowa. The valley of the Missouri is bounded 

everywhere in the loess region with steep bluffs of that material, 

rising 250 to 400 feet above the low, flat, bottom lands between. Where 

they have been longest subject to erosion the loess, which usually constitutes from one-half to three-fourths of the height, stands at an angle 

of from 40° to 60°, while drift makes a much smaller angle with the 

horizon, and the older rocks stand out as a shelf or shoulder.

Three important streams enter this region from the west the Niobrara, 

the Blkhorn, and the Platte. The first, which barely enters, flows in 

a narrow valley 300 to 400 feet deep. The other two have very wide 

valleys, especially in their middle course, and are depressed from 250 

to 300 feet below the general level. Their slopes nearly coincide with 

the slope of the region.
TODD.] TERRACES OF THE LOESS REGION. 63

Tributary streams and creeks are numerous throughout the whole 

region. They are fed by perennial springs, and usually run in narrow 

ravines from 5 to 20 feet deep.

Terraces. Although the subject of terraces will be treated more 

fully in another place, a few words seem called for in this connection. 

Along the principal streams the present flood plain is at an elevation 

of from 5 to 20 feet. The bottoms of their valleys are principally 

occupied by land upon this level. Traces of other benches from 15 to 30 

feet are not infrequently of considerable extent. Besides these more 

recent terraces there are conspicuous traces on most streams of a terrace at from 60 to 100 feet above the present stream. Traces of this 

high terrace are found along the Missouri from Herman to De Soto, in 

Washington County, Nebraska; also in the vicinity of Fort Calhoun 

it is finely exhibited for several miles. At North Omaba and at Bellevue it has considerable extent and an altitude of about 50 feet.

Along the Platte we find a high terrace on the north side of the 

present valley extending from Hall County, where it is low and much 

obscured by sand hills, to the vicinity of Fremont, where it has an 

altitude of about 80 feet. Its northern edge is marked by the lower 

course of the Loup Eiver, Shell Creek, and Maple Creek. There are 

ancient channels connecting these streams with one another at their 

nearest points. Its width is from 3 to 4 miles. From the vicinity of 

North Bend an old channel, 8 miles in width and on the same level with 

the terrace to the north, extends southeast along the east side of Sand 

and Wahoo creeks to the vicinity of Ashland.

Along the Elkhorn the terrace before mentioned, north of Fremont, 

extends northward on the west side of the Elkhorn to Scribner. Little 

trace of this terrace has been found above that point, partly because it 

is obscured by sand hills, partly because the region has not been fully 

examined upon that point.

Traces of this high terrace are found along Bazile, Beaver, Bow, and 

Logan creeks in Nebraska. In Iowa traces of it are found along the 

Big Sioux near Beloit and Fairview, and along several o'f the streams 

on the east side of the Missouri, which have not, however, been examined sufficiently to warrant a more complete description.

Elsewhere, and in general, the topography of the loess region finely 

illustrates the principles of erosion when applied to a homogeneous 

deposit. Eemote from streams the hills have a gently rounded form, 

extending to the edge of the deep ravines which furrow the bottom of 

the valleys. These ravines increase in depth toward their head, where 

they terminate abruptly with perpendicular or even overhanging banks. 

Toward the principal streams the slopes of the hills gradually become 

steeper. Where undermined by eroding streams they frequently present 

bare perpendicular faces 20 to 50 or even 100 feet in height. In general 

the topography is of the erosive type prevalent in massive sandstone 

regions, for the loess resembles sandstone in its resistance to the various
64 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

weathering agencies. From its tendency to stand in steep slopes along 

the streams Professor Swallow, of Missouri, early named it the Bluff 

deposit.

Sand hills. Beneath, the drift over much of this region is a deep 

deposit of fine sand presumably belonging to the Pliocene epoch. In 

the northern portion of Cedar and Knox counties the lower valleys are 

much widened by the unusual recession of their sides, which may be 

ascribed to their undermining because of the presence of this deposit. 

The sand is considerably mingled with the soil and gives a pleasing 

smoothness to the landscape.

This sand deposit comes to the surface and occupies much of the 

country west of the Verdigris and the ancient channel before mentioned, 

which runs southeast from Creighton. The western boundary of the 

loess is there, and as far south as the Platte, obscured by the advance 

of the sand eastward. Sand hills and "clay hills" are indescribably 

mingled. The "clay" closely resembles, if it is not identical with, the 

loess. It probably is a deposit of the Loup River epoch. The ancient 

channel between Creighton and Pierce, more especially south of its 

summit, shows an interesting series of transverse ridges of sand, vast 

ripples, as it were, rising from 25 to 60 feet above the intervening 

clayey meadows. They are at quite regular intervals of 1£ miles. 

Traces of sand are found in the wash of the hillsides as far east as 

Cedar County. At several other localities also there occur sand hills 

which, though formed by the wind, have had their material brought 

into the region by the instrumentality of streams. The Elkhorn and 

the Platte, flowing through sandy regions, accumulate large quantities 

of sand in their bars and bottom lands. When this sand is driest and 

most widely exposed the whole region is subject to prevalent winds 

from the northwest; the result is that, wherever these streams run 

toward the southeast for some distance, large quantities of sand are 

blown from the valleys out upon the upland. In this way one may 

take a map and with considerable confidence tell where such sand hills 

will be found. They have been observed occupying several square 

miles south of Stanton. They are prominently developed, and are 

more conspicuous because of their elevation east and southeast of 

West Point. They are frequently interspersed with smajl ponds. 

South of the Platte they have been observed near the mouth of Bone 

Creek northeast of David City, and in a very extensive area south of 

Kearney. They also occur in corresponding positions along the 

branches of the Loup Eiver. Much of the broad valley north of the 

Platte is occupied by sand hills.

DRIFT DEPOSITS OF THE LOESS REGION.

The drift of this region may become the subject of much controversy 

as concerns its origin. We therefore propose to present, as completely 

as our space will allow, the data which have been gathered.
TODD.] DRIFT DEPOSITS OF LOESS REGION. 65

The lowest and most important formation is here, as elsewhere, the 

till. It presents the usual appearance of a homogeneous matrix of 

clay containing pebbles and bowlders scattered through it, with rarely 

any trace of stratification or segregation of any sort. It also contains 

irregular masses or pockets filled with stratified gravel, sand, or silt. '

Color. The prevalent color, when unaffected by weathering or leaching, is a bright lead blue. Sometimes, however, it is a dull grayish 

brown. It abounds, especially in its lower portions, in white pebbles 

of limestone and quartz, which in a fresh surface present a striking 

appearance upon the blue background. The upper portions of the till, 

where it has been long subject to weathering, or where the frequency 

of porous layers or seams has carried the surface waters into the clay, 

are of a yellowish appearance, which below sometimes shades into a 

reddish color and above into a dull buff.

Joints. The clay always presents a jointed appearance, these joints 

 running in all directions, dividing a deposit into polygonal masses. 

These masses are continually subdivided as the process of weathering 

goes on. In the freshly exposed blue till these masses may be 3° or 4 

feet across, and the seams are correspondingly prominent. They 

appear in some cases, which we may consider an earlier stage, as 

mere cracks cutting the mass irregularly. They more frequently 

show traces of accumulation in the form of thin calcareous or seleuite 

plates. Seams have been found where the selenite plates were from 

one-eighth to one-half inch in thickness. In some cases the selenite 

shows a coating of flour-like gypsum, and in some cases, toward the 

surface of the deposit, where it is more changed, the whole seam is 

filled with such material. The color of the blue clay adjoining these 

seams gradually changes through different stages to a dull yellow. As 

the selenite plates increase in thickness these weathered portions as a 

rule also increase in thickness. Some of the measurements of observed 

cases are as follows: Measuring from the center of the seam either 

way, one-eighth inch flour-like gypsum, one-eighth inch drab clay, 

three-fourths inch bluish, then the surrounding blue clay; another, 

one-half inch cre'am-colored core, 3 inches yellow clay, 2£ inches whitish yellow, then the blue clay. More convincing evidence in favor 

of the conclusion that the yellow till is merely the weathered portion 

of the blue could scarcely be imagined. This change of color in this 

case corresponds with what is uniformly observed of the drab-colored 

layers of the chalkstone, of the similarly colored beds of the Benton 

and the Pierre clays, and also of the blue limestone of the Carboniferous and Paleozoic rocks generally.

Local indications of subaqueous origin. There are several features of 

the till in this region which favor the conclusion that it is of subaqueous .origin. While the previous description may be taken without 

qualification as to general structure, there are exceptions found, as 

Bull. 158 5
66 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

follows: (1) Its colors are sometimes arranged in a horizontally banded 

manner. This has been observed repeatedly along the Platte southwest 

of Fremont, where ashy and chalky layers occasionally appear; (2) 

while the erratics usually have no perceptible arrangement, they are 

sometimes arranged in horizontal lines; perhaps a dozen pebbles lie 

within a few feet of one another upon the same level, where as many 

more of similar size could not be found in as many yards; (3) another 

fact which, although it does not pertain to the structure of the till, has 

an important bearing on the question of its subaqueous origin, is the 

resting of the till upon the nearly horizontal surface of stratified sand 

and clays of pre-Glacial origin without their slightest distortion.

The upper portion of the till which presents the yellowish colors frequently abounds in calcareous concretions, some of irregular globular 

form, others, occupying. the larger seams, of sheet-like form. Sometimes these concretions have to a considerable degree the appearance 

of disintegrated chalk.

RED CLAY.

The second member of the drift we will designate as the red clay, 

for no other characters seem more constant. It usually lies above the 

till. It is never below it, but sometimes is found where no till occurs, 

and it is sometimes wanting between the till and the loess above. Its 

more common characters, besides its brownish-red color, are: (1) It is 

much more clayey than the loess above, and, especially in its upper 

portion, becomes more loamy than the till 'below; (2) it uniformly presents a stratified appearance, layers of clayey silt alternating with 

thicker layers of purer clay. Erratics even several inches in diameter 

frequently appear in it, and usually in a more or less stratified condition. These are found in greater abundance toward the base of the 

formation. Its upper portion, for several feet in depth, may be entirely 

free from them. Its stratification may be obscure either when it has

been somewhat weathered or when the exposure is of a more clayey 

stratum.

Its upper surface is nearly always distinctly marked, but its lower 

surface not infrequently passes into the till without a clear line of separation. This feature has been noted at lower levels near the principal 

streams. In the northwestern portion of the region under consideration 

it is overlain by a heavy deposit of gravel, but as a rule the loess 

rests directly upon it. The darker and redder shade of this member is 

without doubt due to the greater abundance of ferric oxides, and may 

indicate that the formation has been more exposed to the air. It may 

find an analogy in appearance, if not in origin of color, to the weathered 

portions of ferruginous sandstones.

GRAVKL AND SAND DEPOSITS.

The third member of the drift is composed chiefly of gravel and sand 

beds, which also abound, usually in their upper portions, with bowlders.
TODD.] DRIFT DEPOSITS OF LOESS REGION. 67

These occur mainly in the vicinity of the Missouri and the Big Sioux, 

their greatest development being in Knox County, Nebraska, and Minnehaha County, South Dakota. In the former locality it constitutes 

the bulk of the drift.

RELATION OF THE DRIFT TO THE UNDERLYING FORMATIONS.

The formations found beneath the drift are arranged in general in 

strips extending north-northeast to south-southwest. First in the 

northwest corner of the region come the Pliocene sands and clays, 50 

to 100 feet in thickness. Their southeast margin, at least of their 

thicker development, extends approximately from near the northwest 

corner of Dixon County past Coleridge, Stantou, and Columbus, southward. An area along the Split Rock in Minnehaha County, South 

Dakota, is also doubtfully referred to this epoch. Similar deposits 

have been observed also along the Big Sioux east of Canton, and 

nearer Fairview, South Dakota, and northwest of Sioux City; also 

near Lemars and Oherokee, Iowa. This formation along the Missouri 

rises to an elevation of nearly 400 feet above the river in Knox County, 

Nebraska, and diminishes in altitude to the east. Along the line outlined as bounding its thicker development it does not diminish much in 

altitude toward the south. The Missouri, Elkhorn, and Platte southeast of this line have cut through it to the older formations below, 

and, it would seem, have removed much of its thickness. The Niobrara 

chalkstoue appears next east of and underneath the Pliocene. Its 

eastern limit approximately extends from near Brandon, South Dakota, 

southward along the Big Sioux, where it is exposed at Canton and 

Akron, also at Ponca, west of Dakota City, at West Point, Skull 

Creek, Milford, Pleasant Hill, and beyond. The Bentou clays are 

but feebly developed. The next formation, the Dakota sandstone, 

appears quite prominently. Its eastern limit extends from near Dakota 

City past Tekama, Louisville, Beatrice, and beyond. It is found also in 

detached areas near Lewis and Eed Oak, and northeast of Sioux City, 

Iowa. The upper Carboniferous underlies this and extends farther 

west than the east limit of South Dakota. It occupies the remainder 

of the loess region in Nebraska and Iowa, with the exception of small 

detached areas of Tertiary of indefinite extent.

These rocks seem to have been excavated in the form of a broad valley along the Missouri, with its bottom from 15 to 150 feet above the 

present level of the Missouri, but in the bottom of this valley the iuiinediate channel of the Missouri and other streams seem to have been 

excavated to the present depth or even to a greater.

The drift, where it has been observed, rests upon the surface of the 

underlying formations without disturbing them, except in a few rare 

cases. The general fact may be illustrated by numerous sections taken 

from Knox County, Nebraska, and a few from southwestern Iowa. In 

the former locality the drift is found^ in some places resting upon a
68 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

deposit of volcanic ashes more than 3 feet in thickness, which, though 

very friable, shows no disturbance. About a mile east of Osmond it 

was found resting on a gray pebbleless clay, and conformably. In Mills

FIG. 14. Exposure showing base of the till north of Pacific Junction, Iowa.

County, Iowa, typical blue till was found resting upon a grayish-brown 

clay from 5 to 10 feet in thickness containing no pebbles, and this in turn 

upon sand (fig. 14). Neither showed signs of disturbance. Near BenFIG. 15. Exposure showing base of the till uear Berks, Nebraska.

nett and Eoca, Nebraska, drift was found resting upon Carboniferous 

clays without apparent disturbance. Near Berks, Nebraska, it was 

found resting upon an inclined surface of stratified sand with no traces 

of disturbance in either (fig. 15).

STRIATION OF UNDERLYING ROCKS.

While what has been given seems to indicate the general gentle 

deposition of the drift, at least in deeper or more protected localities of 

the old surface, there are a number, of cases where great force has* been 

exerted in. a horizontal direction. Stride have been observed in the 

following localities: About Sioux Falls the surface of the quartzite is 

planed and striated generally toward a direction varying from S. 8° E. to 

S. 43° E., but some were from the west. Southeast of Sioux Falls, about 

the northwest corner of Iowa, the surface of the quartzite is smooth 

and striated in a similar manner, in direction from S. 8° E. to S. 53° E., 

the majority of cases corresponding with the course of the Big Sioux.
TODD.] STRIATION OF UNDERLYING ROCKS. 69

A few miles north of Valley Springs striae varying from S. 8° E. to 

S. 63° B. were abundant on the polished red quartzite. So far as is 

known, no distinct striae have been observed on any other formation 

except the Carboniferous limestones south of the Platte in Nebraska 

and adjacent portions of Iowa. Very faint indications of motion from 

the north-northwest of superincumbent blocks of bowldery clay were 

noticed south of Boca, Nebraska. At Bennett, about 9 miles east, the 

surface of the limestone was found planed and covered with striae indicating a movement S. 41° to 43° W. This was on the northeast side of a 

hill looking toward a valley opening in that direction. A rod or two 

west of that point a few striae toward S. 17° W. were found, and still 

farther west at one point striae were found toward S. Cl° W. and S. 9° E. 

It is a notable fact that this latter locality was simply a few square feet 

of surface on the same level surface with many square rods of limestone 

which, though covered with till, showed no signs of smoothing or striation. On the north side of the valley a mile away another slight trace 

of striae was found; indicating motion toward S. 88° W. South of 

Plattsmouth a considerable surface of the limestone, about 40 feet 

above the river, is planed with striae from east of north.

Upon the limestone ledges 3 or 4 miles south of Pacific Junction, 

Iowa, striae are found at localities differing about 50 feet in elevation. 

They are mainly of two sets, S. 9° E. and S. 40° E. Meek, in Hayden's Final Eeport on Nebraska (p. 92), records near the mouth of the 

Platte S. 100 w. [mag.]. Dr. White in his Iowa report, Vol. I, p. 94, 

mentions a locality opposite Council Bluffs, now obliterated, 6 to 8 feet 

above high water, where the direction was S. 41° W. Prof. S. Aughey, 

former State geologist of Nebraska, reported striae near Beatrice, Koca, 

and Syracuse, also along the Platte at several points, which have an 

average direction of S. 19° E. In a quarry south of Unadilla, Nebraska, 

though no striae were found, the different blocks in the upper layer 

were tipped down toward the north without being apparently moved 

from their position. Two miles northeast of Tabor, Iowa, planation 

was widely shown, but the stone is now removed and the direction has 

not been ascertained.

DISTRIBUTION OF THE DRIFT.

For convenience under this topic, we will divide the drift into 

Nebraska, Dakota, and Iowa divisions.

THE DBIFT IN NEBRASKA.

South of Niobrara, Nebraska, at an elevation of over 400 feet above 

the Missouri, is an extensive exposure of clayey gravel capping the 

hills. This seems to be from 15 to 25 feet in thickness and to rest upon 

light-colored clay. Farther south the loess appears above it, and 

bowlders abound in it, especially in its upper portion. East of the 

Bazile there is the same general appearance, but below tine sand begins 

to show itself in the sides of the bluffs.
70 MORAINES OF SOUTHEASTERN SOUTH DAKOTA.

Volcanic ash stratum. Underneath the drift a layer of grayish-white 

volcanic ashes begins to show itself 5 or 6 miles southwest of Santee 

Agency and is exposed here and there for at least 6 miles eastward. The 

localities noted are SW. £ sees. 27 and 35, T. 33 N., B. 4 W. At the former 

place it is underlain by a stratum of laminated clay crowded with freshwater shells. Prof. E. E. Call has determined them to be mostly Urnnophysa decidiosa. This stratum has been observed to be more than 3 

feet thick. The ash seems to pass both laterally and above into a 

whitish marl. Botn are 450 to 475 feet above the Missouri Eiver.

Mr. Andreas Lundteigen, chemist for the Yankton Cement Works, who 

was interested in the deposit from a business standpoint, has kindly 

given me the following analysis of a sample taken from the top of the 

former bed on Mr. Wakana's land: Silica, 72.44 per cent; lime, 0.55 per 

cent; alumina and oxide of iron, 14.78 per cent; loss by ignition, 4.28 

per cent; total, 92.05 per cent. A sample from the bottom did not 

differ materially,

A stratum exactly similar in composition has been found near West 

Point (PI. XI), on the West Blue southwest of Milford, and also along 

the Missouri about 7 miles north of Omaha, Nebraska (PI. XII). At 

all points it occurs in the drift, not below it. At West Point it is found 

from 4 to G feet thick, at the second point 1 to 5 feet, and near Omaha 

18 inches. Specimens were submitted to Mr. J. S. Diller, of the Geological Survey, who has pronounced them volcanic dust, composed chiefly 

(90 per cent) of minute angular fragments of pumiceous glass. Besides 

these are numerous (10 per cent) grains of quartz sand, well rounded, 

indicating that the ashes fell into quite water.

If, as seems not improbable, these different beds were deposited simultaneously, how may we account for their being below the drift in Knox 

County and in the drift in Cuming and Seward counties? By reference to a list of elevations further on we find the altitude to be now in 

the first case over 1,600 feet, and in the other less than 1,500, the second 

being less than 1,350 feet. Even making liberal allowance for changes 

of level since their deposition, we can readily believe that the deposition 

of drift, assuming its subaqueous origin, began at the lower levels before 

the volcanic outburst, and did not reach the northern localities till later. 

The apparent haphazard occurrence of the ashes in Knox County may 

be readily explained by their preservation only in lagoons along the 

ancient Mobrara. When they fell on the land rains would soon wash 

them away, and when in the main stream they would be swept onward 

and mixed with other sediments. The idea that they fell in ponds is 

further supported by the occurrence of the fossiliferous clay immediately 

below.

If we accept the more commonly received hypothesis that the till is 

the product of land ice, we may suppose that the older ice sheet 

advanced to the altitude of West Point from the Des Moines Valley, 

while the occupation of the Dakota Valley was later. Or we may sup-
U. S. GEOLOGICAL SURVE

NEAR VIEW OF VOLCANIC ASH STRATUM IN BLUFF ABOVE WEST POINT, NEBRASKA,
TODD.] DRIFT IN NEBRASKA. ' 71

pose that the deposits were simply formed in bayous along the adjacent 

streams when they were flowing at high levels. It should not be forgotten, however, that it is by no means certain that the ash beds in different localities were deposited at the same time.

There is little loess upon the surface of the drift for several miles east 

of the Bazile, and erosion has cut this bed of gravel into abrupt knolls, 

which are very conspicuous. Near the Bazile and along How Creek 

erosion has also sapped the sandy formation so that the gravel-topped 

knobs have sunk bodily toward the streams.

Farther east, about 5 miles southeast of Sautee Agency, the loess 

begins to so cover the drift that it is almost entirely hidden, except 

along the face of the bluffs toward the Missouri. Its continued gravelly character is well shown southwest of Herrick, about what is called 

the Devils Nest, a descriptive name for two or three very deep ravines 

excavated through the loess, drift, and Tertiary sands to a depth of 

over 100 feet. One of the most complete sections found is at or near 

the northwest corner of T. 32 N., E. 3 W. The whole section, from the 

summit of an adjacent hill, is as follows:

Section near the northwest corner of T. 32 N., E. 8 W.

Foet. In.

Slope, probably loess, though bowlders were found near the summit.... 50 0

Loess exposed ......................................................... 4 0

Stratified sand, gravel, and bowlderets of granite, greenstone, etc....... 0 8-18

Reddish, loamy, joint clay containing northern pebbles................. 15 0

Fine white sand, stratified ............................................. 7 0

Reddish clay and rusty sand ........................................... 4 0

Stratified lead colored clay ............................................ 1^-2 0

Fine sand ............................................................. 15 0

Wet efflorescent clay .................................................. 0 8-10

Sand .................................................................. 4 0

Clayey sand ........................................................... 3-4 0

Whitish marl alternating with layers of sand........................... 50 0

In another section several rods west, below the loess, which was 

about on a level with a corresponding point in the preceding-section, 

the strata were as follows:

Section several rods ^vest of the preceding.

Feet,. In.

Stratified gravel and bowlders, about four coarse layers with fine sand alternating, all sorts of northern erratics present.......................... 4| 0

Laminated loamy clay with two layers of pebbles ......................... 3 0

Fine gray sand passing into 2 feet of chalky clay.......................... 16 0

Grayish cheeky clay, stratified, with fossil planorbis and other fresh-water 

shells, and a few small pebbles.......................................... 3 0

Sand containing fragments of chalkstone and of large bones and teeth...... 1 0

Chalky clay .............................................................. 6 0

A general section showing several exposures noted is given in 

fig. 16.

The gravelly drift is also made prominent by its capping long spurs 

extending northward along the northern edge of the loess table-land.
72 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

The tops of these are nearly in a line, about 390 feet above the river, 

while the gravelly layer back under the loess is 450 to 475 feet. They 

appear like the remnants of a gravel-topped terrace, but as they have

nocounterpart elsewhere, 

it seems probable that 

they, like the lower hills 

along the Bazile, have 

been let down from an 

original high position by 

the escape of fine Tertiary sand from beneath 

them. Farther east, 

along Weigand and Beaver creeks, gravelly terraces again appear at a 

still lower level j these, 

though containing the 

same material as the 

higher deposits already 

described, are doubtless 

a rearrangement of them 

as terraces of these 

streams. The gravelly 

drift underlain by sand 

appears to have once extended as a sheet over 

the whole region of the 

Beaver and the Bows, occupying the most of 

Cedar County. It has 

been affected by erosion 

so much that it is not 

now continuous except 

along the divide.

In a high hill 3 or 4 

miles southeast of Yankton the summit of the 

drift is less than 300 feet 

above the river, and 

shows much sand in connection with it. In the 

bluffs south of St. Helena 

the chalkstone rises 225 feet above the river and only a few bowlders 

and pebbles appear upon it, below the loess, which there rises only 40 

feet higher. At several points along the West Bow incomplete exposures show the drift thin and with frequent bowlders, resting uniformly 

on sand. Curlew Spring, a copious spring or system of springs about 4
II. S- GEOLOGICAL SURVEY

BLUFF ABOVE FLORENCE, NEBRASKA, SHOWING ASH STRATUM.
TODD.] DRIFT IN NEBRASKA. 73

miles south of Hartingtou, comes from the underlying sand, as does 

also a magnificent spring 4 miles west of Coleridge.

The sand below the drift, which is there nearly pure coarse stratified 

gravel, is finely shown in a cut 2£ miles'north of Coleridge. It is pure 

and stratified in thin layers (PI. XIII).

In a cut near Hartington, Nebraska, the drift was found resting upon 

a calcareous marl much resembling loess, and differing from it principally in its more distinctly stratified character. It furnished numerous 

speciuiens of fresh-water shells, which Prof. E. E. Call, to whom they 

have been submitted, has identified as follows:

Valvata tricarinata Say.

Succinea obliqna Say.

Gyraulus parvns Say.

Sphajrium striatinum Lam.

Limnopliysa decidiosa Say.

Limnophysa palustris [?], imperfect specimen.

Two or 3 miles east of Hartington a similar exposure was noticed in 

the bank of the East Bow. It seems probable that this is a late Tertiary deposit, probably belonging to the Equus beds of Cope.

The gravelly character of the drift continues south along its western 

limit as far at least as Creighton. East of that place, at an elevation 

of about 110 feet above the station, abundant traces of gravel are found 

by the roadside through a vertical distance of about 10 feet, above 

which the loess begins to appear. About 5£ miles east of Creighton a 

well freshly bored was noticed at the place of Mr. D. C. Cleveland, who 

kindly gave me several facts, not only in regard to his own well but in 

regard to those in the vicinity. This well was on the general level, 150 

feet above Creighton, or 1,767 above the sea. A section of the well was 

nearly as follows: Seventy or 75 feet of loess-like clay with no pebbles 

above but with numerous calcareous concretions, a few pebbles below, 

passing into pure gravel, which extended down to a depth of 80 feet. 

Below the gravel was 10 feet of fine sand. This, he told me, was 

the common experience in wells of that vicinity. He had the impression that water was found nearly upon a level. A well half a mile 

west, starting about 30 feet lower, is about 125 or 130 feet deep 

and has 22 feet of water. In it there was only about 40 feet of the 

loess-like clay. In digging wells blue clay is not usually found, but in 

a well about 2 miles southeast, in a valley, 2 or 3 feet of blue clay 

was found above sand. Whether the blue clay contained pebbles 

or not he was unable to say. A well bored half a mile south, 100 feet 

deep, was nearly or quite all in sand. A north west-southeast line 

passing about half a mile south of his place marks the northern 

boundary of a sandy region the ancient channel passing by Creighton 

and Plainview to the north branch of the Elkhorn. This line seems part 

of the eastern boundary of the region supplied with water from the Pliocene sands. No further trace of drift was found till we came to the upper 

branches of the Bow in the southern part of T. 33 N., E. 1 W-., where
74 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

the drift appears again as a gravelly terrace in the sides of the principal 

valleys. An old resident of the region remarked that the bowlders 

were mostly upon the surface. This was found to agree with our observations. Because of the unusual variations of the barometer the elevation of the drift at this point was not well determined, but from its 

relation to the general level of the country we judge it somewhat lower 

than near Oreighton. About Hartiugton and Coleridge beds of gravel 

and bowlders appear up to an altitude of about 1,760 feet. This elevation was noticed in the sides of the valley near Coleridge. The elevation 

in a high range of hills 4 miles southwest of it rises to about 1,625 feet. 

In the wells about Hartington, according to the testimony of Mr. Beed, 

a well digger of the place, the wells are from 36 to 50 feet in depth, 

those upon the lower land being shallower. The water is found 

apparently upon a level. After passing through soil and several feet 

of silt and alluvium (this I judge to be the case from a railroad cut 

near town) white clay in layers is struck and below that plastering 

sand with pebbles in which specimens of petrified wood are frequently 

found. At Coleridge, as stated by Mr. Miller, of that place, wells are 

35 to 40 feet in depth, passing through about 6 feet of black soil, 17 

feet of clay of loess-like character, 3 feet of sand, and then clay again. 

At Concord.there is 4 feet of soil, then sand without the clay. Passing 

eastward from Coleridge, bowlders and pebbles are found to the eastern 

edge of the valley upon the terrace-like tables in the valley before 

described, underneath the capping of silt, but after leaving the valley no 

pebbles are seen until the valley of the East Bow is crossed. They tben 

appear upon a few hillsides about the same distance below the highest 

hilltops as before. No more drift is noticed until we reach the Missouri 

at Ponca. Everything is covered with loess, which in the valleys has 

washed down or crept down from its original higher position. In the 

bluffs south of Vermilion the following section was observed:

Section of the bluffs south of Vermilion, South Dakota.

Loess with a clayey stratum about 10 feet above its base, and below a few lay- Feet, 

ers of small pebbles interspersed, the base itself a distinct horizontal line.. 40-50 

Bowlders and stratified gravel with clayey patches.......................... 3-4

Coarse orange-colored sand, light above, with reddish streaks................ 3-4

Fine white saud with yellowish streaks ...................-.................. 5-6

Cretacous clays of the Benton group.......................................... 95

Level of the Missouri.

At the landing at Ponca another fine exposure was found, for which 

we had time to make only a hasty estimate, as follows:

Section at the landing at Ponca, Nebraska.

Feet. In.

Loess with several feet of sand below.................................... 50 0

"Chalkrock," exposed................................................... 10 0

"Chalk rock," not clearly exposed....................................... 40 0

Dark shale............................................................... 10 0

Dark shale or hard clay with yellow layers................................ 4 0

Coal..................................................................... 8-10

Rusty sandstone ......................................................... 4 0
U. S. GEOLOGICAL SURVE

BASE OF DRIFT NEAR COLERIDGE, N
TODD.] DRIFT IN NEBRASKA. 75

Along the Missouri, south of Ponca, drift exposures are not prominent. The older formations rise high and are capped with high bluffs 

of loess. Southwest along the railroad in Dakota County the cuts 

exposing drift in a<ny form are scarcely noticeable. Clusters of bowlders are reported along the valley of Elk Creek. Near Wakefleld a 

few bowlderets and northern pebbles are sometimes struck in deep wells, 

but generally south of the watershed bounding the immediate valley 

of the Missouri that is, including the short streams flowing directly 

toward it the whole surface of the country is so deeply buried with 

loess that northern erratics are almost unknown. Even experienced 

well diggers will sometimes aver that none are to be found.

More recently the opening of the Pacific Short Line from Sioux 

City to O'Neil, Nebraska, has afforded much better opportunities for

FIG. 17. First railroad cut east of Osmond, Nebraska. Scale same as on fig. 18.

examining the surface formations of this region. It is particularly 

instructive between Randolph and Osmond, where it crosses the 

divide between the west branch of the Logan and the north branch 

of the Elkhorn. West of Osmond no traces of northern "erratics are 

found except a few pebbles, which are likely to have washed from the 

hills immediately east. The universal subsoil is sand, which for the most 

part shows the shaping action of the wind. It occasionally contains 

grains as large as one-fourth inch long, usually of a light feldspar. In 

the valleys pebbles, mostly of quartz of different colors and well 

rounded, and unlike those commonly found in the drift, are found.

The valley of the North Elkhorn, in which Osmond lies, is bounded 

on the east by hills more abrupt and higher thau those on the west, 

and bowlders appear on their sides. The difference in altitude is 

doubtless due to erosion which has taken place since the deposition of
76 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

the drift. About 1 mile east of Osmond, and about 25 feet higher than 

the station, an exposure at the foot of a north slope showed typical yellow till with few pebbles, resting conformably upon a drab pebbleless 

clay at least 2 feet thick and exposed for 2 rods. The junction was 

even, horizontal, and abrupt. One passed completely into the other in 

less than 6 inches. The relations are shown in figs. 17 and 18. As the 

road rose along the east side of the valley the exposures of yellow 

till were found appearing regularly, usually with the upper surface 

rounded similar to the present surface, but not always corresponding, 

sometimes showing no correspondence. It is overlain by sand, loess, 

red loamy clay, or gray till, without trace of an old soil or distinct 

weathering. The ashy colors may perhaps indicate action of vegetation 

near water level, or in some cases more likely more direct derivation 

from the drab Cretaceous clays. The annexed figures" show the relations of surfaces of the different formations.

FIG. 18. Cuts east of Osmond, Nebraska.

About 150 feet above Osmond, on the west slope of the divide, a flat 

area covering perhaps a square mile was noticed. From the cuts along 

its west and north sides it seemed to be underlain by till and topped 

with 20 to 30 feet of loess and sand. These last seem to intermingle 

indiscriminately. In some places they are interstratified. The adjoining figures sufficiently illustrate their relations. The higher ridges, 

rising 50 to 75 feet higher than this flat, are probably composed entirely 

of these materials. They usually extend northwest to southeast.

Besides the formations already mentioned there is also found a 

chocolate-colored variety of the reddish loam, which is darker than the 

usual shade of the loam. It is usually found in patches upon the latter 

at higher levels. The gray, pebbly clay which was noted nearly filling 

one of the cuts on the west side of the till flat also shows more of a 

chocolate shade above.
TODD.] DRIFT IN NEBRASKA. 77

One very remarkable feature of the clays shown at higher levels, in 

places very conspicuously, is the occurrence of great cracks like ordinary mud cracks in their general features and arrangement, but on a 

vastly larger scale. They are frequently 8 to 12 inches wide at the 

surface of the clay and penetrate it 4 to 6 feet. They are filled with 

sand from the deposit above. The sand' in the cracks and that directly 

above them for 2 or 3 xeet is unstratified, while the surrounding saud 

is distinctly and horizontally stratified. The saud is not in the least 

mixed with the clay in the sides of the cracks. The cracks penetrate 

yellow and chocolate or gray clays alike.

Several inferences may be fairly drawn from these phenomena: (1) 

The till was very wet when first exposed to the air; (2) it became very 

dry before the advent of the sand; (3) the chocolate clays and yellow 

clays were deposited about the same time as the clay and have passed 

through similar circumstances; (4) we could not well imagine stronger 

proof of the subserial deposition of the sand. Its horizontally stratified 

character does not indicate deposition in water.

Very limited exposures of pebbly clay have been found, however, 

about 12 miles north of Winside, and as far southeast, along Humbug 

Creek; also at a few points along the north branch of the Elkliom, 

which have been mentioned elsewhere. Bowlders have been reported 

also as found along Plum Creek and Rock Creek, in Cuming County. 

Four or 5 miles northwest of West Point are two bends in the Elkhorn which cut deeply into its western bank. The upper one is the 

more complete. It displays the formation from the general level of the 

country down to the level of the stream, as follows: <>

Section on the Elkhorn 4 or 5 miles northivest of West Point, Nebraska.

Feet. In.

Loess,'it8 lower surface horizontal and distinct; just above it 3 or 4 feet of 

compact clayey layer, with a stratum in its upper portion about 8 inches 

thick blotched with blackish, doubtless due to carbonaceous matter....... 50 0

Red clay, its upper half more loamy, homogeneous and without pebbles. 

The first 6 feet above its base presents four horizontal bands of cheeky 

clay 8 to 10 inches thick, and the next 6 feet above four more thin ones 

of similar character. These all alternate with sandy or loamy layers. 

Pebbles of red quartzite are occasionally found in thin, short layers, 

which occur as high as 20 feet from the base............ .................. 45 0

Whitish clay............................................................... 4 0

White clay or marl......................................................... 2 0

These last two pass laterally into a stratum of volcanic ashes a few rods 

farther west, away from the river. This volcanic ash bed is horizontally 

stratified in very thin layers, its texture as fine as flour; its color, for the 

most part grayish white with yellowish streaks in its upper portion.

Muddy sand, passing laterally into obliquely stratified sand with bowlders 

below ........... ................._........,............................. 2£ 0

Fine greenish clay, thicker at some points.................................. 6

Yellow till................................................................. 4 0

Compact blue till........-................-............'.................... 5' 0

Level of the river.
78 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

In the lower bend the top of the till is scarcely exposed above the 

surface of the water. No distinct trace of the ash stratum has been 

found there, and the horizontal base of the loess, which is very distinctly exposed, showing above the carbonaceous layer, is only about 

50 feet above the stream.

At the town of West Point, in a deep clay pit near the summit of a 

hill northeast of town, a combined section is as follows:

Combined section at West Point, Nebraska.

Feet. 

Loess, sandy above, showing wind-drift structure .......................... 30

Dark carbonaceous clay with numerous fragments of shrubs and roots in its

upper portion ........................................................... 3-4

Reddish joint clay without pebbles, yellow and laminated above ........... 4-5

On the hillside west, 40 to 50 feet below the bottom of the pit, drift 

pebbles are scattered.

Perhaps 15 feet lower on the hillside, by the schoolhouse, is an exposure 

showing about 15 feet reddish and yellow till, with a few bowlders. 

The western side of its lower portion slopes abruptly and is overlain 

for several feet by horizontally stratified sand, which probably corresponds to the sand in the lower part of the high terrace along the Elkhorn farther south. The bottom of this exposure is estimated to be 

about 30 feet above the railroad, or 45 feet above the Elkhorn.

Where the railroad crosses the west branch of Maple Creek, in the 

northern part of Colfax County, the following section is exposed:

Section in Colfax County, Nebraska.

Feet.

Loess surrounding a core of yellow till which is 15 feet in height above the bottom of the cut. This above contains many chalky seams, and exhibits reddish clay and sand upon its slope.................. -.;....................... 25

Eight feet lower the base of the yellow till is exposed in the side of a bank

near by and below it. 

Drab-colored pebbly clay and fine stratified sand .............................. 2

Clay.......................................................................... H

Fine stratified sand........................................................... 3

Between Tekamah and Oakland various cuts along the railroad 

expose the loess, u old soil," as its dark lower portion is frequently 

called, and red clay down to the till.

About a mile above Florence a fine section reaching down to the surface of the Missouri may be made by combining two great exposures 

which are not far apart. From the top of the till west it is as follows:

Section of bluff near Florence, Nebraska.

Feot. 

Timbered slope ................................................................ 50

Loess exposed, lower half considerably darker than above. No dark stratum 

near base and red clay lacking ................................ ............... 35

Till, yellow above, but mostly blue. In a few places small pockets, containing 

stratified gravel and a few large ones below filled with very fine yellow compact massive sand ........................................................... 75

Level of the river.
TODD.] DRIFT IN NEBRASKA. 79

About a half mile north of the last a very different section was finely 

exposed by excavating for gravel at the time of the building of the 

Omaha waterworks near Florence. The following is the section (see 

PI. XII):

. Section half mile north of the last.

Feet. 

Slope...................................................................... 10-20

Loess...................................................................... 25-30

Stratified clayey loam, yellow, with many calcareous concretions............ 7

Volcanic dust like that found farther west, except stained with rust ........ 1$

Yellow clayey loam, slightly stratified...................................... 5

Fine gray sand ............................................................ %

Coarse sand and pebbles obliquely stratified, mostly of northern origin...... 20

Unexposed, probably part blue till, judging from sections on the opposite

side of the river .......................................................... 15-20

Level of water in the Missouri.

From many sections found along the Platte west of Fremont the following is chosen as probably the most instructive. It is found near the 

southern end of the old bridge southwest from town.

Section west of Fremont, Nebraska.

Feet. In.

LoesSj the dark lino 3 feet above its base appearing only as thin wavy streaks 30 0 

Red clay, passing into drab and rnsty below............................... 11 0

Whitish clay with many chalky concretions and numerous pebbles, some of

them scratched. This deposit ends abruptly at one end and at the other

tapers out............................................................... 2 0

Similar reddish and drab clay with pebbles, but with few if any bowlders.. 22 0 

Light greenish clay, blotched with white, extending horizontally at least a

rod. Its ends are hidden................................................. 1 2

Reddish clay, passing below into 20 feet till which is yellowish above, but the

blue color rises in places near the top..................................... 11 0

Level of the river.

Farther east, near the present bridge, a layer of coarse sand obliquely 

stratified replaces the blue till to the height of 10 or 12 feet above the 

river. This is probably a portion of the sandy substratum found in the 

high terrace developed along the north side of the Platte. Farther 

west, southeast of Timberville, the strata are the same as before given, 

except that the till is not exposed and the base of the till is 30 feet higher, 

and between it and the red clay is a stratum of blackish mucky clay 4£ 

feet thick. In the bluff's south of Linwood bowlders and pebbles 

abound at a level lying between 50 and 115 feet above the valley to the 

north. At the lower level several feet of fine stratified sand appears 

aud probably rises considerably higher. Northwest of Schuyler, on 

the slope of a high bluff overlooking Shell Creek and the Platte Valley, 

many northern pebbles are found at the height of 175 to 225 feet 

above the latter. Bowlders abound upon the hillsides in a strip from 

10 to 12 miles wide, extending along the western side of Saunders and 

Lancaster counties nearly to the southwest corner of the latter.

In the railroad cuts between Den ton and Berks, southeast of Lincoln,
80 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

there are abundant exposures of the drift. About 3 miles east of the 

latter station the following section is found:

Section southeast of Berks, Nebraska.

Feet.

Slope from the top of one of the highest hills, which was strewn abundantly 

with bowlders, to the edge of a deep cut..................................... 70

Yellow till, mostly exposed, with a few bowlders ............................... 30

A few rods southwest of this, in another cut overlapping, is found 

Fine sand obliquely stratified ..............................................'.... 15

The yellow till shows obscure traces of stratification in its lower portion in the form of layers of pebbles, and banded arrangements of 

colors parallel with its lower surface. The sand, on the other hand, 

bears marks of erosion. Its strata end abruptly against the till, but 

no trace of distortion in them was discovered. ° Their eroded surface 

slopes abruptly toward the east. In lower cuts on the east the fine sand 

occurs under the drift, sometimes with greenish clay interstratified 

with its upper layer (see fig. 15).

About 3 miles south of Pleasant Hill, about 20 feet below the general 

level, the recent digging of a well furnished unusually favorable opportunity for obtaining the following section:

Section near Pleasant Hill, Nebraska.

Feet. 

Black soil..................................................................... 2£

Yellowish clay, passing into the next.......................................... 6

Reddish clay.................................................................. 6

Lighter clay, distinctly separated from, but conformable with, the next........ 22

Fine stratified sand, quite compact. Two red quartzite bowlders were found on 

its upper surface........................................................... 6

Sand interstratified with clayey layers......................................... 8

Niobrara chalkstone.

Numerous small bowlders of red quartzite, greenstone, etc., are found 

in the deeper ravines in that vicinity on the same level with their occurrence in the well. The chalkstone also crops out farther east along 

Turkey Creek, and underneath it is said to occur a dark carbonaceous 

layer, probably of the Benton group.

About 8 miles southwest of Milford, in a deep bend in the West Blue, 

which cuts into its southern bank, the following interesting section 1 

was found:

Section S miles southwest of Milford, Nebraska.

Feet. 

Soil .......................................................................... 2

Red gritty loam............................................................... 6

Stratified loamy clay with thin strata, rounded white quartz pebbles, passing 

into the next................................................................ 9

Clayey gravel, with a few bowlders of red quartzite, passing into the next..... 3

Stratified loamy clay, with streaks of pebbles.................................. 15

Light-gray siliceous earth, volcanic ashes very evenly laminated............... -J-£

1 This section was published in Science, 1887.
TODD.] DRIFT IN SOUTH DAKOTA. 81

Section S miles southwest of Milford, Nebraska Continued.

Feet. 

Clay, darker above, below passing into the next............................... 1£

Gray sand, with thin sheets of clay 6 to 12 inches apart........................ 5

Coarse sand, with pebbles and bowlders of various sorts resting upon an uneven 

surface below............................................................... 1

Hard greenish joint clay.................. ................ .... ................ 6

Slope......................................................................... 8

Water of the West Blue.

A few rods distant a less complete but similar section shows the 

volcanic ash layer 5 feet thick, and it appears along the sides of a ravine 

for several rods.

The deeper draws west of the Big Blue, in southern Seward County, 

frequently show beds of gravel corresponding to the upper portion of 

this section in which the pebbles are mostly, if not entirely, of western 

origin. Incomplete exposures of drift exhibiting .weathered till are 

found in favorable circumstances over most of the region east of the 

bowldery strip outlined above, but the deep deposit of loess renders 

their occurrence quite infrequent. Near the Missouri, and at some 

points quite remote, the loess is found to rest upon the older rocks 

without traces of drift between.

THE DRIFT IN SOUTH DAKOTA. 

In South Dakota there is a limited area outside the moraine which is 

occupied with loess. We proceed to consider the drift underneath it.

At Vermilion there is a terrace which rises about 80 feet above the 

flood plain of the Missouri. The southern edge of this terrace extends 

nearly due east from this place to Brule Creek. The structure of the 

terrace is unusually well shown in cuts at Vermilion. The mass of it 

is composed of a pebbly clay, the upper portion of which is quite 

homogeneous and of a yellowish color. In this were noticed certain 

levels several feet apart, in which bowlders were more abundant. 

Below the pebble clay is less homogeneous, showing pockets of sand, 

some stratified obliquely. The prevalent color of the whole is blue. 

No exposures were found lower than 20 feet above the river. Wells in 

the town show gravel 125 to 160 feet below the surface. The upper 

surface of the pebble clay was evidently eroded before the mantle of 

loess which covers it was put on. This loess is not considered of the 

same age as the more extensive deposit, but is probably simply a 

deposit of silt in comparatively recent times. Upon this terrace are 

frequently found basins resembling those upon till. The upper plain 

of this terrace surface extends north to the moraine and east to Brule 

Creek at a very uniform level. The exposures along the Vermilion 

River indicate that the same general characters prevail throughout.

A study of the cuts along the railroad between Beresford and

Calliope indicates that the drift here, instead of being gravelly, as in

northern Nebraska, is for the most part clayey, the stony ingredients,

including sand, forming perhaps less than 30 per cent. Between the

Bull. 158 6
82 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

moraine and Brule Creek, in shallow cuts, yellow pebble clay and 

loess-like clay are interstratified, perhaps by wash from loess exposures 

above. In the cuts near the side of the long north-south valleys running into Brule Creek from the north the pebble clay below shows a 

washed surface, and sometimes a thin layer of gravel, while sand prevails in the end of the cut toward the valley. Everywhere at low levels 

(and there are no deep cuts very high above the bottom of the valleys) 

the correspondence of the drift with the present surface of the country 

is clearly seen. In the summit cut, between Alcester and Calliope, there 

are exposed loess and an irregular layer of reddish clay lying above 

the yellow pebble clay which in some places show 5 feet or more. A 

few small yellow sand pockets were observed with stratified gravel in 

their upper portions. This was at an altitude of 90 feet above Alcester. 

In a cut about 25 feet in depth 2 miles west of Calliope, on the south 

side of the valley of a small stream and about 100 feet above the Big 

Sioux, the pebble clay was exposed to such depth as to exhibit a 

decided bluish cast in its lower portion, although the upper 15 or 20 

feet showed the usual yellowish appearance. As in the cuts near Vermilion, the yellow passes insensibly into the bluish pebble clay. Here 

the yellow banded seams, dividing the blue till into polyhedral masses, 

were finely shown. Another peculiar feature of the pebble clay in this 

cut was the existence of cracks which resemble immense mud cracks, 

descending 3 or 4 feet from the surface and widening above to 4 or 5 

inches. These cracks were filled with a coarse yellow sand. With 

this exception no deposits of sand were found in the cut. Similar 

cracks were found to be more numerous in some of the cuts farther 

west. In this same cut the pebble clay was capped with loess, an 

eroded surface with several inches of gravel and occasional bowlders 

separating them. Another feature was well shown in this cut which 

occurs not infrequently elsewhere, especially at lower levels in the till. 

These were patches of lead-colored clay, free from pebbles and resembling the Cretaceous clay in texture and color. These are often 2 or 3 

feet thick and from 4 to 5 feet to a rod in width. The most rational 

explanation that has presented itself is that the core of the hill is of 

such clay, and that while the pebble clay was forming this became 

mixed, either en masse by the thrust of ice or by becoming plastic it 

flowed down on the already deposited drift. Different cases may have 

been formed in these different \vjays.

Near the Big Sioux west of Calliope the bottom of the drift, as 

marked by an exposure of travertine rock, is about 65 feet above the 

stream, while its top is 125 feet, and has the appearance of the edge of 

a terrace. Farther north, west of Eden, the top of the drift near the 

Big Sioux is about 160 feet above the Big Sioux. Along the Big Sioux 

north of Eden is a high terrace of stratified gravel about 65 feet above 

the Big Sioux, and in a slide just west the Tertiary (?) deposits, composed of lead-colored shale and sand, rise about 50 feet, above which
TODD.] DRIFT IN SOUTH DAKOTA. 83

comes first about 4 feet of fine sand, then pebbles and bowlders. 

The drift continues from that upward to 117 feet upon a spur extending from higher land farther west.

Along the Dakota side of the Big Sioux below Beloit, Iowa, preGlacial deposits are found finely exposed at several points. They are 

especially conspicuous where the stream has encroached upon the highlaud in close proximity to the moraine. Since the formation of the 

bowldery terrace which slopes down from the plain about Canton to 

the mouth of Rock Eiver, the stream has found the pre-Glacial beds so 

easily corraded that it has slipped off from the terrace and cut down 

from 70 to 80 feet below it.

On or near sec. 18, T. 97, E. 48, the Big Sioux has encroached upon 

an unusually high bank on the south. About 250 feet above the stream 

is a terrace corresponding in height to the upland east of Beloit, but 

not so high by 50 feet as the till surface a mile or two west, which we 

consider a part of the moraine. The terrace is not fully exposed, and in 

some places the sliddeu bank makes the thickness of strata somewhat 

doubtful. Beginning at the top of this terrace, we have made out a 

section as follows :

Section on the Big Sioux Eiver, 3$ miles east of Fairvieio, South Dakota.

Feet.

Loess..................................................................... 6-10

Till with irregular stratified sand strata toward the bottom. The lower 20 

feet is blue and almost free from pebbles. Possibly equivalent to the 

pebbleless clay east of Canton and Sioux Falls .......................... 100-110

Fine sand with large rusty concretions of upper portions and a few fragments of large pearly shells (Unios?). This stratum is of undetermined 

thickness and is doubtless a source of the very copious springs along the 

base of the bluff farther east which deposit travertine................... 20

Unexposed. Probably much of it is a pebbleless clay of Cretaceous age.... 110

Level of the. Big Sioux, about 1,200 feet above the sea.

Half a mile farther east is exposed 5 to 6 feet of black clay capped 

with a layer of shaly sandstone which passes below the water of the 

Big Sioux, forming slight rapids. This dark clay resembles closely 

the Bentou clay as seen opposite Vermilion, but no fossils were found 

to decide the point. It is probably a rearrangement of this clay, or 

possibly a portion of the original deposit itself, which has been successfully used in making ornamental brick near Fairview.

There is little doubt that the clay and sand near Eden, South Dakota, 

and those shown in the cuts east of Canton, also north of Sioux City, 

belong to the same formation with those appearing in this section. 

The sand may be of very late Tertiary age.

Along the Big Sioux between the falls and Brandon the drift 

abounds in gravel and bowlderets, the latter being largely formed of red 

quartzite. From near the level of the bottom lands above the falls 

there extends a well-marked terrace down the river, sometimes upon 

one side of the river and sometimes upon the other. In its upper por-
84 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

tion it is composed of gravel, which is coarse above. Extensive expo 

sures are found along the railroad. Its height above the river 2 miles 

west of Brandon, according to railroad levels, is about 80 feet. Near 

the northwest corner of T. 101, E. 49, are" high hills, composed almost 

entirely of gravel, forming a ridge parallel with the stream and risiug 

in their highest portion 210 feet above it and about 20 feet higher than 

the gentle slope which rises from it southward toward the moraine. In 

this the.coarser material seems to be above. An exposure about 50 

feet below the summit showed coarse plastering sand.

About the town of Sioux Palls are numerous exposures, some of 

which are shown in figs. 22-26. In general they show in higher places 

thin deposits of loess, as though deposited along the stream when flowing at higher altitudes. Below this, in some places, comes yellow pebble clay, usually with the washed surface. In one case a confused mass 

of bowlders is found at this horizon, in others a dark layer 1 to 3 feet, 

as though an old soil or mud bed formed in the stream. This is usually 

from 30 to 40 feet above the level of the Milwaukee station. In a few 

cases this seems to be overlain by yellow pebble clay instead of loess.

In the cuts northeast of Sioux Falls, along the line of the Illinois 

Central Railroad, there is an exposure of deposits similar to those 

noted east of Canton. They are as follows:

Section northeast of Sioux Falls, South Dakota.

Feet. 

Loose loess ..................................... ........................ 5-6

Drab, cheeky yellowish clay. A few black siliceous pebbles, more numerous 

below, with some white pebbles and sraall bowlders of red quartzite....... 6-7

Dark soil-like clay, checked with white concretions of black pebbles, some of 

them trap and flat........................................................ 3

Similar, but lighter, containing calcareous concretions and black pebbles. 

Coarser bowlders come, in at the top horizontally. Three rotten granite 

bowlders were found, though there were many others which were solid .... 5

Gravel, with numerous bowlders in the upper portions...... ................. 10-12

A drab plastic clay with few pebbles, weathering a creamy ocher (older till).. 5-6

The top of the last stratum is very little higher than the Chicago 

and Northwestern station. The gravel stratum is quite variable in 

thickness, and the pebbly clay above shows a dark stratum of clay 

which has the thickness and general appearance of a soil, but in other 

cases is not present.

About Garretson and north for 2 or 3 miles is a small driftless area, 

which is of peculiar character. The bed rock is Sioux quartzite, much 

fissured, and traversed with channels which are 60 or more feet in depth. 

The Split Eock, the principal stream, seems not to have cut to the 

bottom of some of the old channels. Upon this rests a loess-like loam, 

in places passing into fine sand. Its thickness has not been determined, partly because it is not easily differentiated from the loesf, 

which is probably of more recent date. In a careful examination of 

both sides of the Split Eock for 1 £ or 2 miles north of Garretson no
TODD.] DRIFT IN IOWA. 85

case of worn surface or northern erratics was found, except a very few 

scattered over the surface of the underlying rock, which may easily have 

washed from north of the area. This feature is in marked contrast 

with the surface of the rock a little west of the Palisades, where the 

loam is absent and the rock is worn and grooved by the action of the 

ice. The thickness of the pre-Glacial loam at Garretson has not been 

clearly determined, but a thin edge of clayey gravel is found over-. 

lapping the loam a little east of Garretson. and a stony deposit of 

northern sand and bowldery clay is observed upon the summit of several knobs which may be detached remnants of stream beds or bowldery 

terraces and which rise 125 or 150 feet above Garretson, which place is, 

by railroad level, 1,496 feet above the sea. The connection has not 

been traced, but it seems probable that this stony stratum corresponds 

with the bowldery layer at the bottom of the till east of Canton, and 

that it marks the level of the discharge of water along the east edge 

of the Dakota lobe at a time somewhat antedating the occupation of 

the outer moraine. If this, however, is correct, the difference in the level 

and the consequent rapid currents southward would account for the 

coarser material. This, it will be observed, would correspond to the 

earlier deposition of till east of Canton. A heavy gravel deposit east 

of Sioux Falls would correlate well with this same deposit.

In the loam capping the high terrace just east of the Big Sioux, above 

the falls and opposite the city of Sioux Falls, there were found in 1894 

two tusks, three or four teeth, and fragments of bones of a large mammoth. The tusks were over 6 inches through at the base, and the portions remaining were over 7 feet long and much curved. This terrace 

rises to about 60 feet above the present stream, and was probably the 

flood plain of the river during the earlier occupation of the outer 

moraine. At a lower level large bones, supposed to be of a mastodon, 

were reported at an earlier date. Probably from the lower level also 

came the skull of a musk ox now in the museum of the University of 

South Dakota.

A few miles north of Clark, in Clark County, outside of the moraine, 

beds containing wood and fresh-water shells were struck, in digging 

wells, 25 to 30 feet below the surface. This is the only case which seems 

to correspond with the forest beds reported from eastern Iowa and 

Illinois, and these are not certainly known to be covered by till.

THE DRIFT IN IOWA.

In a section opposite Fairview drift was found to a height of 240 

feet above the stream. The Big Sioux has there worn deeply into the 

highlands on the east side. An extensive slide, probably caused by a 

softening of the Cretaceous or Tertiary clays below, has exposed about 

50 feet of pebble clay, the upper portion of which is yellow, the lower 

blue, exhibiting the selenite seams, with the yellow layers adjacent, 

like those shown in the cut west of Calliope and already described.
86 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

From a series of cuts between the Big Sioux east of Canton and 

Inwood, Iowa, as well as a careful study of slopes and reports from a 

few wells, we construct the following section:

Section on Big Sioux, east of Canton, Iowa.

Feet.

Loess, with an undetermined thickness of till probably occupying the lower 

portion. From some reports as well as from the cuts it would appear that 

nearly or all of it was loess, but from the distribution of water and the 

reports of other well-diggers it seems that half or two-thirds of it is till.. 90-100

Gravelly clay in places. This seems to be the same which is conspicuously 

developed as a shoulder along the hillsides next the Big Sioux farther west. 10-20

Pebbleless loamy clay^which weathers a creamy yellow (older till?).... ...'.. 50

A fine stratified sand without gravel, but no northern erratics. This sand 

probably corresponds to the sand west of Fairview. It is water bearing, 

furnishing a spring in a railroad cut...................................... 18-20

Unexposed, probably Cretaceous ........................................... 60-75

Level of Big Sioux, 1,227 feet.

Bast of Kruger's mill, back of a terrace about 50 feet in height, the 

drift appears on the south side of a small stream showing a section, 

beginning about 108 feet above the stream, as follows:

Section east of Kruger's mill.

Feet. 

Reddish pebbly clay with some sand .................................. 1...... 9-10

Stratified sand, with sheets of clay obliquely set, and from a half inch to 6 

inches thick ............................................................... 24

Blue till with an irregular surface above ..................................... 5-6

Higher than this section the slope shows pebbles to a height of 180 

feet, where bowlders are more common. North of the small stream, 

along what appears to be a much-eroded terrace, bowlders and gravel 

occur to the height of 125 feet, above which there is 30 feet of loess.

FIG. 19. Sandpit section east of McCook, South Dakota.

Three or 4 miles west of Larch wood shallow wells show 5 to 10 feet 

of loess, below which comes yellow pebble clay or till. This seems to 

be the prevailing character of the upland region of Iowa throughout 

Lyon County.
TODD.] DRIFT IN IOWA. 87

Seven or 8 miles northwest of Sioux City, about St. Onge's place, 

as mentioned by Dr. White in his report, and not far from the ranch of 

D. H. Talbot, are several exposures showing the more recent deposits 

overlying the Cretaceous Inoceramus limestone beds, which form a conspicuous shoulder along the bluff's for many miles. The higher level 

of the Cretaceous is about 140 feet above the Big Sioux. Above this 

lies a bed of waxy yellow clay with irregular upper surface. It seems 

to be derived from the weathering of the limestone on which it rests. 

Above this is a bed of gray sand, coarser below. This has been sought 

for plastering purposes in Sioux City. A sketch of one exposure is 

shown in fig. 19. In no case have I seen more that 12 feet exposed, 

but it is probably much thicker farther back. The sand passes above 

into a greenish joint clay without pebbles. Upon this rests a thin layer 

of reddish till containing the usual northern erratics, and just above 

conies the loess. All the exposures studied indicate that the clays and 

loess have been let down and distorted by the escape of the sand from 

below. A generalized section would be as follows:

Generalized section near Sioux City, -loiva.

Foot.

Loess . ...'.................................................................... 50

Eeddisli till ................................................................. 3-5

Greenisli joint clay without pebbles.......................................... 2-5

Gray sand, clayey above, coarser below ...................................... 7-12

Yellow waxy clay............................................................ 5-?

Cretaceous No. 3............................................................. 140

Level of Big Sioux.

About a mile northeast of the railroad bridge across the Big Sioux, 

near Riverside, are several sandpits. In one a large lenticular mass 

of till was found in the loess. This was described and figured in 1895. 1

One mile above Sioux City, between the summit of Dakota Point and 

the river, the following section may be found:

Section 1 mile above Sioux City, Iowa.

Feet. 

Slope......................................................................... 25

Loess, exposed, with several feet at base darkly covered with carbonaceous 

matter...................................................................... 150

Yellow till with an uneven surface above, reddish and loamy .................. 55

Low water in the Missouri.

About a mile farther up the river, at the base of the bluff, is an 

exposure of gravel about 60 yards in length and 15 to 20 feet in thickness. Its base is unexposed, but its upper surface, which is about 50 

feet above the water in the Big Sioux, is a horizontal line, and the loess 

stratified below rests directly upon it. A remarkable feature in the 

gravel is the occurrence of three great bands of coarse gravel and 

cobblestones, alternating with finer material, which dip abruptly to the 

south through the whole height of the exposure. The dip above is 

about 18°, but gradually diminishes toward the base.

1 Proo. Iowa Acad. Sci., Vol. II, pp. 20-23; also by H. F. Bain in Iowa Geol. Kept., Vol. V, p. 284.
88 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL.ISS.

A study of this locality, which is near Eiverside Station, subsequent 

to extensive removal of the gravel revealed the following facts, some 

of them quite puzzling. At first view it seems a clear case of till 

between two beds of loess. The gravel shows a level surface for several rods, and at the south end it has been found to be at least 30 feet 

thick. At that depth water, probably on a level with the river, prevented further excavation. Above the gravel at the south end rises 50 

to 75 feet of loess. In it were found a few shells of Limnaea and Sphaeriuui, which have not been observed elsewhere in the loess of this region. 

The summit of the hill back rises about 130 feet above the. river.

At the north end of the exposure and 100 yards from the last the 

section above the gravel is as follows:

Section near Riverside Station, Iowa.

Foot. 

Slope, loess................................................................... 50

Loess, exposed................................................................ 5-6

Reddish till, thinning and dropping to the south and running out in about 80 

yards........................................................................ 18

Massive loess-like silt, containing Succi-nea avara, similar to those now living on 

the bluff back, blotched above with carbonaceous matter, with a few fragments of water plants (?)................................................... 6

Upper surface of the gravel somewhat interstratified with the silt, and contain- 

, ing the same Succinea.

Within a quarter of a mile farther north the top of the Cretaceous 

is evenly exposed about 80 feet above the river, and above it fine sand 

with pebbly clay above rising to 90 to 190 feet, the beds resembling 

those already noted near Talbot's. The most plausible explanation 

suggested at present is, therefore, that the gravel pit shows a comparatively recent formation in the base of a high terrace, possibly corresponding to that south .of Sioux City.1

At Missouri Valley, back of the brickyard, there is found the following section:

Section at Missouri Valley, Iowa.

Feet.

Loess, exposed, with "charcoal streak" a few inches above the base pretty 

well developed for this region. This loess shows crevasses or slight cracks 

nearly vertical from top to bottom ........................................ 90

Drift exposed mostly reddish clay, loamy above, more stony below, and passing 

into blue till below .............................................. ......... 40

Thirty feet above station.

One to 1£ miles north of Council Bluffs are found three great sand 

pits in the side of the bluffs. They are known from their owners' 

names as Lawlor's, Clark's, and Cassady's sand banks, naming them 

in order beginning with the most northern. At Clark's bank we find 

the most complete exposure, although some of the members are bet1 Compare also an explanation in Proc. Iowa Acad. Sci. (1895), Vol. II, pp. 20, 23.
TODD.] DRIFT IN IOWA. 89

tor represented in the other banks. The section at Clark's bank is as 

follows:

Section at Clarlc's sand bank, 1 to 1^ miles north of Council Bluffs, Iowa.

Feet. 

Loess, exposed, -which is sandy below ....... ................................ 20

Dark clayey loam............................................................ 3-4

Coarse sand, obliquely stratified in thick layers, with a layer of clay 6 to 8 

inches in thickness, interpolated 12 to 15 feet from the bottom ............. 40

Gravel...................................................................... 5

Blue till, white pebbles....................................... ...... ........ 8-10

Unexposed, but probably mostly till (level of the lake)...................... 25

At Lawlor's the sand is slightly consolidated in its upper layers, 

forming a sandstone a few inches thick. A row of angular blocks of 

clay appears in the sand 12 to 15 feet above the base. The gravel is 

found 8 feet thick, obliquely stratified, with layers 8 to 12 inches in 

thickness. The blue clay appears as before.

At Cassady's bank, 2 or 3 miles north of Council Bluffs, Iowa, we 

have the following section:

Section at Cassady's sand lank, 1 to 1$ miles north, of Council Bluffs, Iowa.

Feet. In. 

Slope.................................................................... 80 0

Loess, exposed........................................................... 20. 0

Clayey loess, with concretions............................................ 3-4 0

Sandy loess ........................ .....\ ................................ 3-4 0

Coai-se sand, suitable for plastering, found in eight or nine layers 3 to 10 

feet thick, all obliquely stratified, dipping toward the south, excepting 

one or two ............................................................. 45 0

Fine wet clay, uniform in thickness ...................................... 1 3

Rusty, coarse sand with cobblestones below; some of the layers consolidated.................................................................. 10-12 0

Below the last number a copious spring comes out, which, probably 

like many others, marks the upper surface of the till.

From 4 to 5 miles north of Pacific Junction, along the base of the 

bluffs, are some remarkable exposures showing the base of the blue till. 

This is seen to extend horizontally for a mile or more, being exposed 

very distinctly. In the principal exposure the following section is 

found:

Section 4 miles north of Pacific Junction, Iowa.

Feet. 

Loess....................................................................... 15

Yellow, reddish, and loamy pebble clay .................................... 15

Slope, indicating much rusty sand.......................................... 55

Consolidated sand ......................................................... %

Clayey gravel in patches, with fine yellowish sand, and strips of yellow and 

blue till intermingled with them ......................................... 12-15

Typical blue till, with its base very even and horizontal...................... 3-5

Joint clay without pebbles, of a dark brownish gray, passing below, in its 

thickest portion, into reddish clay with horizontal bauds of rounded concretions from 4 to 6 inches in diameter; its lowest surface very uneven..... 11-17

Light gray, fine, stratified sand, containing small globular concretions ...... 9-10

Level of Missouri bottom lands.
90 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

About 2 miles north of Pacific Junction the following section is 

exposed:

Section % miles north of Pacific Junction, Iowa.

Feet.

Brownish clay, passing up into soil.......................... ...........>.... 3

Light-colored sandy marl, passing into marl below, and with black and white 

concretions above......................................................... 3

Layer of chalky concretions with black interior............................. £

Very fine sand, obliquely stratified, passing abruptly below into the next.... 6

Coarse sand and small quartz pebbles ....................................... 4

East of Pacific Junction, in a spur of the bluffs near Keg Creek, is 

a deep railroad cut with the following section:

Section near Keg Creek, Iowa.

Feet. 

Loess.......................... ^...... '. ..................................... 50

Dark-reddish or chocolate-colored loam extending horizontally across the 

exposure ................................................................'. 3-4

Yellow till, uneven above and with loess filling the depressions under the 

dark stratum, many chalky concretions above and large, irregular sand 

pockets below. Remains of a young mammoth was found in the base of the 

loess or top of till ........................................................ 20-25

Unexposed.................................................................. 4-5

Irregularly bedded limestone, Carboniferous................................. 4

At the point of the bluff south of Pacific Junction 2 or 3 miles, at 

one of a series of copious springs, there is the following exposure of 

drift:

Exposure 2 miles south of Pacific Junction, Imva.

Feet. 

Stratified gravel, somewhat consolidated ............................ ........ 2-6

Dark blue till, resting directly upon the next................................ £-1

Gray limestone, which is striated in a direction S. 15° E. (mag.); this is about 

20 feet above the bottom land ............................................. 2

One-half mile farther south and 60 feet above the bottom land is 

another glaciated surface, several yards in extent, upon a layer of 

compact blue limestone about a foot thick, resting upon clay. Strise 

are found upon its surface having the following directions: The deeper 

ones S. 18° B. and S. 26° E. There are also some S. 54° E. and S. 52° E., 

very distinct, and still smaller ones S. 70° E. About a rod east of the 

first locality striae were found S. 14° E. and S. 8° E. There are now 

only a few inches of rusty sand resting on this surface, with the loess 

above.

In southwestern Iowa numerous exposures have been examined along 

the various railroads. It seems unnecessary to enter into details, but 

better to give only a general statement. As a rule, the loess shows 

four or five clayey layers, from a foot to a foot and a half in thickness 

at its base, with frequent traces of carbonaceous matter in its lower 

portion. Underneath this appears the red clay, first without and then 

with pebbles, passing below into till, which in some cases, as near 

Clarinda, is 40 feet or more thick.
TODD.] ELEVATIONS OF DRIFT. 91

The junction of the loess appears as a rule only in the higher cuts 

upon the summits separating the principal streams flowing into the 

Missouri. Lower cuts, which are the most common, present an eroded 

surface of till upon which the loess rests, with the red clay occasionally appearing between. Usually the surface of the drift is approximately parallel to the present surface of the country, its convexity 

usually being less. The till presents the same features which have 

been noticed elsewhere.

ELEVATIONS OF SURFACE OF DRIFT .IN LOESS REGION.

These elevations, from the nature of the case, are less definite than 

some which have been given. For the most part they are of points 

where the loess and drift show their original relation to each other. 

They are in every case barometric. Those showing old soil or charcoal 

streaks are marked with an asterisk *); eroded surface under deep 

loess with an obelisk (t).

Elevations of surface of drift in loess ref/ion.

Locality.

Elevation 

above the 

Missouri.

Elevation 

above the sea.

Feet. 

South of Niobrara.............................. 425-460

Devils Nest........... .......................... 450-475

East of Creighton .............................. 470

East of Osmond ................................ (t)

East of Norfolk................................ 415

Twelve miles north of NortLsitle................ 415

Clarkson ................... .................... '530t

Five miles northwest of Schuyler............... 560

Near Linwoocl.................................. 390

Bone Creek, east of David City................. 510

Germautowu ................................... 575

East of Milford ................................ 500

Berks........................................... 530-555

Eight miles southwest of Milford ............... 555-580

South of Pleasant Hill.......................... 560

Four miles southeast of'Yankton................ 255

South of St. Helena............................. 150

Five miles northwest of Hartingtou............. 385

Five miles southwest of Hartington............. 450

West of Coleridge ...:.......................... 590?

Northeast of Emerson .......................... 260?

Five miles northwest of West Point............. 380*

Southeast of Timber ville........................ 330*

Southwest of Fremont.......................... 270*

feet.

1, 645-1, 680

1, 650-1, 680

1,690

1, 700-1, 760 

JL, 620 

1,620 

1,560 

1,572 

1,400 

1,595 

1, 530 

1,450

1, 450-1, 475 

1, 475-1, 500 

1, 475 

1, 440 

1,320 

1, 555 

1. 610 

1,710? 

1,360? 

. 1,426 

1,340 

1,280
92 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158. 

Elevations of surf ace of drift in loess region Continued.

Locality.

East of Fairview, South Dakota ................

West of Eden...................................

Seven miles northwest of Sioux City ............

Blair, Nebraska ................................

About 4 miles northwest of Florence ............

West of Silver City.............................

East of Pacific Junction ........................

West of Minden ................................

, West of Marne ..................................

West of Red Oak. ..............................

Elevation 

above the 

Missouri.

Feet. 

475

400

205

255

225?

235

245

220?

270

350

175

95

290

190

140*

75

75

70 

150

170

50*

100

100*

225

225

335*

200

125*

185

275

240

345

380*

Elevation 

above the sea.

Feet. 

1,400

1,320

1,125

1,175

1,465?

1, 450

1,450

1,400

1,370

1,450

1, 280

1,200

1310

1200

1130

1165

1065

1055

1110»

1160

1000

1065

1055

1550

1560

1475

1230

1230

1350

1150

1075

1140

1230

1154

1265

1320

The elevations given from Iowa are mostly taken from the summits 

between important streams. The junction of the red clay and loess 

often lies considerably lower in the cuts adjacent to these.
"OLD SOIL" AND CHARCOAL STREAK. 93

DELATIONS OF DRIFT TO LOESS.

The relations of the drift to the loess vary in different localities, 

Prof. N. H. Winchell in his annual report for 1877 published observations indicating the gradual passage of loess into till in the southwestern 

part of Eock County, Minnesota. This would nearly correspond to what 

the writer has elsewhere described in sections where the till and loess 

are connected through the medium of the red clay. Where the upper surface of the latter is rendered indistinct by the absence of the "old soil" 

and the loamy and pebbleless character of the red clay the statement of 

Professor Winchell would be exactly realized. Such have been frequently found by the writer in southwestern Iowa, especially where 

deposits have been somewhat disintegrated by weathering or leaching. 

Nevertheless, that the normal relation, at least in the central portion of 

the region, is one of distinct division between the red clay and loess 

seems borne out by observations which have been recorded above. As 

has been found in numerous localities, the drift often has a very distinctly 

eroded surface, which is marked by its unevenness and by the presence 

upon it of an unusual number of pebbles and bowlders. This washed 

surface, so far as has been observed, is confined to lower elevations; in 

southwestern Iowa to within 100 feet above the present streams. It is 

uniformly found in cuts where the railroad passes through the spurs 

running into a valley. The surface of the drift is convex, but in less 

degree than that of the loess above. Another interesting relation is 

found in the cuts adjoining the more important streams. In such 

cases the drift loses, in a measure, its parallelism with the present surface or with that of the loess, and its culmination in any cut is usually 

toward the more important stream, as would naturally follow from the 

greater erosion of the loess on that side. This is found to hold true 

provided the important stream rises within the loess area.

THE "OLD SOIL" AND THE CHARCOAL STREAK.

Numerous references have been made to the carbonaceous matter 

between the loess and red clay. Where the deposits are well preserved 

at the junctions of these formations there is rarely an absence of carbonaceous matter. It is sometimes in the form of driftwood scattered 

in the clay, as in cuts southeast of Malvern, at West Point, and southeast of Timberville, Nebraska. More frequently it has the appearance 

of a dusky shading of the clay, usually for 3 or 4 feet just above the 

base of the loess. This is frequently true where the driftwood is found. 

The term''old soil" is properly applied to such exposures. Its color 

may often be well described as chocolate, though it is sometimes more 

like that of black loam. The carbonaceous matter is sometimes found 

in wavy streaks scattered through the clay, as though sparingly 

deposited with the embedding of the material. Angular fragments of 

charcoal are distributed in the same deposit, usually very sparsely, but 

sometimes in pockets. These fragments are generally quite minute, but
94 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

in one case they were found nearly half an inch through and apparently 

from sticks 6 inches in diameter. That these fragments are of charcoal 

rather than of rotten wood is indicated, although not proved, by their 

angular character, and the fact that at this same horizon wood is found 

well preserved. From the presence of the charcoal this has been named 

the charcoal streak.

The old soil and charcoal streak are found only where the surface of 

the drift is not eroded. In using the term "old soil" the writer would

PIG. 20. Summit cut between Silver and Keg creeks.

not assume that such is its real character. No unmistakable evidence 

of plants growing in position has been found in it. Although some of 

the fragments apparently are from roots, examination has not shown 

them to be in their natural position, while in other localities, as at 

Malvern, Iowa, the fragments have a slivered and worn appearance, 

as if they had been transported.

Another question arising at this point is whether this stratum is 

more closely connected with the loess or with the red clay. Usually 

the material and structure of the deposit aside from the-carbonaceous 

matter are hardly distinguishable from the loess. Moreover, often the

FIG. 21. Cut on Oraalia and St. Louis Railroad west of Walnut Creek, Mills County, Iowa.

junction between it and the red clay is distinctly marked, while on the 

other hand, although its color ends quite abruptly upward, the body 

of the deposit seems continuous with the loess. We conclude, therefore, that in most cases, at least in this region, the formation is a deposit 

of carbonaceous mud. In some localities, especially the more elevated 

and those toward the western margin of the region, it may prove to be 

real soil. Figs. 20 and 21 illustrate some of the points mentioned above.

SUMMARY.

The drift in this region is represented by three members till, red 

clay, and gravel and sand beds. 

The first is confined mainly, if not exclusively, to a belt along the
TODD.] LOESS. 95

Big Sioux and Missouri from 30 to 50 miles wide iu the northern portion, 

but rapidly widening below Dakota City, so that in the latitude of 

Lincoln it reaches from the Big Blue west of the Missouri to at least 

an equal distance east of that river. The second is found everywhere 

except where its absence can be referred to erosion. In its pebbleless 

form it continues westward indefinitely underneath the " old soil." The 

third is most extensively developed in Knox and Cedar counties, Nebraska, at a high level; but similar deposits are found near the present 

channels of the Big Sioux and Missouri at much lower levels, especially 

southward.

As to elevation, the first is mainly confined to medium and lower 

levels. The second is found at all levels, though more removed by 

erosion at lower levels. The third occurs at higher and lower levels less 

frequently than at medium elevations.

The drift, as was long ago recorded by Dr. 0. A. White, is less prominently developed near the Missouri.

The base of the drift is found where the blue till is wanting, as in 

northern Nebraska, and in the lowest levels along the Missouri Eiver 

in the southern part of the region under consideration; also at other 

locations throughout this region where older rocks protrude to unusual 

height. In other circumstances it is not found.

The drift of the region, so far as has been observed, contains no 

erratics of local origin except within 5 or 6 feet of the original beds.

Striae are of exceptional occurrence even in localities where they are 

found. Disturbance of underlying beds has been very rarely observed, 

and where observed it is of inconsiderable amount.

LOESS.

 We proceed to consider the loess, which covers this region as a 

mantle and, with superabundant folds, spreads farther west and south. 

In our discussion of its characteristics we shall find it convenient to 

transcend the bounds of the drift as before laid down.

By the term loess we would designate, in the present case, not simply 

the kind of deposit, but only the deposits of this kind which were 

made contemporaneously with its principal development in this region. 

The silt capping of the high terraces before mentioned and the bulk 

of some of the more recent terraces are physically indistinguishable 

from'the true loess. The same is true of an older deposit described 

elsewhere.

Structure and composition of the loess. The loess has been so often 

defined that a detailed description is unnecessary. It is composed 

mainly of fine grains of silica, some of which attain the size of 0.2 of 

a millimeter, though much the greater number of particles are less than 

0.01 of a millimeter. These particles are coated, more or less, with 

oxide of iron and calcium carbonate. The amount of the former gives it 

its color, which in the typical form is usually a light buff. With it are
96 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

!

mixed many small grains of clay. The finer ingredients appear to constitute a cement which holds it firmly together, so that it usually stands 

firm like indurated rock, unless softened by moisture. In the latter 

case it has a very slow, creeping movement on slope. It is often traversed by vertical fissures, which in some cases may be compared with 

crevasses in glaciers. In some localities the grains of silica are rather 

angular, even the largest, but more commonly, so far as observation 

goes, the larger grains are more or less rounded, sometimes worn smooth, 

and the smaller grains, though relatively less worn, are apparently as 

much so as could be expected from their diminutive size and the consequent feebleness of their impact during transportation.

Though remarkably homogeneous, it still shows variations in color, 

which are often quite conspicuous when seen over extensive exposures. 

Its usual color is a dull yellow, but it is not infrequently of a light 

ashy hue, with a bluish cast when permeated with moisture. The distribution of these colors forms one of the most reliable evidences of its 

stratified character. In the extensive excavations recently carried on 

near Council Bluffs, Iowa, an obviously darker band could be seen 

when viewed from a distance, marking a horizontal line for half a mile 

or more. This was some 75 or 80 feet above the bottom lands of the 

Missouri. Similar horizontal bauds have been traced in cuts of higher 

elevation and more remote from the Missouri. This obscure stratification has also been found in some cuts to show a curved arrangement 

corresponding to the surfaces above and below. The ashy appearance 

in other cases seems to be a result of more recent leaching of the loess 

by carbonaceous waters. In this way may be explained the frequent 

occurrence of ashy loess near the ends of cuts.

Extent of tlie loess. The boundary of the loess on the west is very 

indefinitely determined, and must necessarily remain so for several reasons : (1) The obscuring of the limit by the encroachment of the sand 

from the west, under the influence of the wind; (2) the possible passing 

of loess into this sandy deposit on the west; (3) the close resemblance of 

the loess to residuary loams and to lacustrine and fluvial deposits of a 

different epoch. In general it may be said to extend along the Elkhorn, Platte, and Eepublican rivers indefinitely westward, while over 

the areas between it extends not nearly so far. As observed near 

Friend and Dorchester, Nebraska, the prevalent deposit is not the typical loess, but is much more clayey, and the yellowish tint is replaced 

by a reddish, so that it resembles a deposit found elsewhere beneath 

the loess. Whether this deposit is really a clayey equivalent of the 

loess or whether it is of older formation has not been determined. It 

has been observed by the writer near Norfolk and thence down the 

Elkhorn to its mouth; also up the Loup Eiver as far as Scotia, and 

along the Platte as far as Plum Creek, and deep deposits of it are 

reported from the vicinity of the North Platte. It abounds, according 

to Professor Aughey, along the Eepublican.
TODD.] EXTENT OF LOESS. 97

The eastern edge of the loess is difficult to determine because the 

deposit is fragmentary and is deeply covered with soil closely resembling that of weathered drift. The presence of pebbles is usually, 

though not always, decisive proof of underlying drift, but much of the 

drift seems covered with a soil in which pebbles are scarce. The eastern boundary of the loess is described by Dr. White in his report upon 

the geology of Iowa, Vol. I, page 109, viz:

Commencing at the southeastern corner of Fremont County, follow up the watershed between the East Nishmibotany and West Tarkio rivers to the southern boundary of Cass County, thence to the center of Audubon County, thence to Tiptop 

(Arcadia) Station on the Chicago and Northwestern Eailway, thence by a broad 

curve westward to the northwest corner of Plymouth County. The last-named 

point is probably very near tbe most northerly point to which the deposit reaches, 

certainly the most northerly one to which it reaches in Iowa.

Further investigation has shown the last statement to be an error. 

Moreover, the loess continues east of the limit named, becoming of 

lighter color, coarser texture, and less homogenous, passing in the Des 

Moines Valley into the second till ot McGee.

According to Prof. E". H. Winchell, of the Minnesota survey, it rises 

to the 1,550-foot contour line in Eock and Nobles counties, Minnesota, 

or geographically it extends nearly to the southwest quarter of the 

former county and the southwest township of the latter, with a narrow 

area along the south boundary of the former county connecting them. 

In Iowa it is found covering most of the surface of Lyon and Sioux 

counties. This continues the boundary from the point last named by 

Dr. White more than 50 miles farther north.

The general statement given in the above quotation is correct, but 

additions may be made to it as follows: While the eastern edge in Lyon, 

Sioux, and Cherokee counties is ill defined, in Sac County it follows the 

watershed, and in Oarroll and Guthrie counties the loess terminates in 

a thick, abrupt edge overlooking the valley of the Middle Eaccoon in a 

way similar to that in which it overlooks the drift region west of the 

Big Sioux in Lincoln County, South Dakota, from the high bluffs east of 

the same stream. This feature was first described by Prof. O. St. John 

in the Iowa reports. It is well shown by figs. 23 and 24 (pp. 101,102), 

taken from the same. It will be remembered that a similar relation 

existed along its northern edge in northern Nebraska and in northwestern Iowa.

In Adams County and adjacent counties in southwestern Iowa the 

loess extends up the valleys of the principal streams, while the drift

?upies the higher country.

'outhward the boundary of the loess has not been well determined.

.rtainly preserves its typical features and undoubted character

ttiong the immediate valley of the Missouri to Kansas City and beyond.

Several of the Missouri geologists have recognized it in the surface

clays covering most of the counties of that State north of the Missouri

Eiver.

Bull. 158 7 -
98 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

Fossils in the loess. Land aiid fresh-water shells belonging to recent 

species are found in great abundance in certain localities of the loess. 

They belong mostly to terrestrial species, but a few are distinctly 

aquatic. These fossils have not been noticed in northern Nebraska near 

the moraine, but mostly in southwestern Iowa and central Nebraska. 

Fragments of unios have been reported from northwestern Iowa, but 

they seem likely to have been derived from the graves of Indians, by 

whom they were used as ornaments. They may have been scattered 

also around camps where they were eaten. In the loess bluffs near the 

Missouri in southwestern Iowa patches of ash-colored loess are found 

connected with faint impressions, which seem to be traces of pieces of 

bark and driftwood, but such can not be positively stated. Some of 

the horizontal streaks and bands of ashy loess may mark the former 

deposition of vegetable matter which by its decay in its porous surroundings has reduced the sesquioxide of iron, which gives the yellow 

tinge to the loess, to a carbonate which has been removed. In several 

localities detached bones and teeth have been found 20 feet or more 

below the surface; but as a whole the loess is a remarkably barren 

deposit.

In some localities certain horizons in the loess are very rich in fossil 

shells over considerable areas. At Missouri Valley, Iowa, 3 or 4 feet 

above the horizontal junction of the loess with the red clay, numerous 

specimens of Helix alternata and Succinea obliqua are found with more 

common smaller species. The exposures exhibiting these are along the 

bluffs facing the valley west.

At Council Bluffs a horizon of similar shells occurs 4 or 5 feet above 

a dark layer resembling what has been called elsewhere the " old soil," 

but in this case it is found far above the base of the loess, at least 40 

feet, and how much more can not be stated, as the drift is not exposed 

at that point.1

Concretions in the loess. These have been well described by Professor 

Call,2 as well as by others earlier. A few notes concerning their distribution may be added. They abound at certain levels, within 100 feet above 

the present bottom lands of the Missouri, in great profusion. They are 

occasionally found in horizontal bands, suggesting their formation 

along an ancient water level. Sometimes, however, especially in 

greater altitudes, they appear in curved lines approximately parallel 

with the present surface. Such a case suggests their correspondence 

with the upper surface of a portion of the loess which at one time was 

water-soaked. Their frequent association with holes formed by roots 

suggests further the idea that they have been formed by the reduction 

of the dissolved bicarbonate of lime to the carbonate by evaporation.

1 ¥or farther and more complete statements regarding the loess fossils of this region, see S. Aughey, 

Hayden's annual report for 1874, pp. 266-269; K. E. Call, Am. Nat., 1882, p. 380; F. B. Meek, Geol. of 

Missouri, vol. 2, p. 215 (this does not exclude fossils from the alluvium); J. E. Todd, Proc. Am. Assoc. 

Adv. Sci., vol. 27, p. 235. B. Shimek, Proc. Iowa Acad. Sci., vol. 5, p. 33.

 ? A paper published in The American Naturalist, May, 1882.
TODD.] ORIGIN OF LOESS. 99

Such an explanation will not, however, explain the curiously cracked 

interior of the concretions. Although their calcareous character is so 

prominent,.a little examination shows that they are largely composed 

of such siliceous grains as constitute the bulk of the loess. That they 

were not first masses of calcareous mud, perfected by concretionary 

action, seems evident from their position, which is usually with the 

longer axis vertical. Their cracked interior, rather than the result of 

its shrinking, as has been frequently suggested, is more probably produced by the expansion of the exterior by the building in of fresh particles from time to time between those already deposited. The age of 

these concretions may not be very great, for they are frequently 

observed in loess which has been recently rearranged.

Besides the calcareous concretions which have been considered thus 

far there are frequently found concretions of iron oxide. These are 

formed universally around decayed roots or root marks, and are sometimes elongated so as to resemble lead pencils in size and shape. 

Usually in their axis is an opening formerly occupied by a root.

Origin of the loess. In comparing the loess with the extensive Cretaceous clays exposed along the Upper Missouri, and evidently forming 

much of the floor upon which the drift sheet of Dakota rests, one is 

struck with the abundance of silica in the former and the almost entire 

absence of it in the latter. Hence the idea that the loess is mainly the 

product of the grinding of the glaciers, at least so far as the Dakota 

lobe is concerned, seems to be erroneous. If, however, we turn to the 

Tertiary deposits of the plains west, we discover vast beds of very 

similar loams, in both the Loup Fork and the Laramie formations. There 

is underneath the prevailing greenish quartzite, which here and there 

caps the table-lands along the Ponca Eeach, a deposit 10 to 20 feet 

thick scarcely distinguishable from the loess. Trace of apparently 

the same formation is mentioned by Prof. N. H. Winchell in his report 

on the Ludlow expedition, as found along the Oannonball.1 It seems 

probable, therefore, that much of the loess material was derived from 

the western tributaries of the Missouri and not exclusively from the 

beds stirred up by the Dakota glaciers, and yet there is a probability 

that these sandy beds may have formerly extended into the James 

Valley, and so may have contributed to the loess through the instru 

mentality of the ice sheet. The calcareous and alkaline ingredients of 

the loess, on the other hand, were probably derived from the alkaline 

clays and chalk beds in southern South Dakota. These have given it 

some of its cementing constituents, which are the cause of some of its 

most peculiar physical properties.

Thickness of the loess. The regularity in both the upper and the lower 

surfaces of the loess before mentioned is likely to mislead one in estimating its thickness. Several writers have apparently taken the distance from the summit of a hill to the highest exposure of the drift

1 See report of Captain Ludlow's reconnaissance of the Black Hills, 1874, p. 23.
100 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BELL. 158.

underneath this as the thickness of the loess. This may result in magnifying it two or three fold. In northwestern Iowa the railroad cuts 

rarely show a thickness of more than 15 feet, and more frequently less 

than 10 feet, and it lies from 15U to 250 feet above the Big Sioux. In 

southeastern South Dakota it is found in a very similar position.

In Fremont County, Iowa, its thickness, as shown by wells, is from 

150 feet at a very few points near the Missouri to 40 or 50 feet near the 

Nishnabotany. It becomes very thin between the Nishnabotany and 

the Nodaway, in Page County. In southwestern Iowa it occurs down 

nearly to the lever of the present flood plain of the Missouri. But 

usually in such cases there are signs of rearrangement it has either 

slipped bodily from a higher position or has washed down, or else forms 

portion of a terrace of the Missouri at a lower level.

In northern Nebraska its thickness, so far as can be determined, is 

rarely over 100 feet in Knox County, and is more frequently less than 

50 feet, but it is elevated from 400 to 550 feet above the Missouri. In 

Dixon County, opposite Vermilion, the loess extends from an altitude 

of 125 feet above the river to 300 feet, and farther back probably to 

350 or 400 feet. It is not unlikely, however, that its base rises even 

more, so that its greatest thickness is near the river, where it attains, 

perhaps, 150 feet. At Ponca it is nearly the same, with its base about 

75 feet above the river.

The lower surface of the loess rests upon the drift, and the relief of 

the surface of the latter may be inferred from its altitudes, which 

were given on a previous page. In most cases, toward the central 

portions of the region the base of the loess is a nearly horizontal plane, 

and here we usually find its greatest thickness. Near Florence its base 

is 75 feet above the Missouri, and it is estimated to be 100 feet in thickness. At Council Bluffs it is probably over 200 feet, but a continuous 

section of more than 100 feet has not been exposed at any one point. 

Judging from the external appearance of the bluffs along the Missouri, 

a similar thickness is attained at several other points from Sioux City 

southward.

The circumstances of the deposition of the loess and its age will be 

postponed until we have considered more fully its relations to the 

moraine and terraces of the principal streams. We now proceed to 

consider more in detail the features of the loess region adjoining the 

moraine.

Relation of the loess to the outer moraine. Beginning near the mouth 

of the Bazile, the northern boundary of the loess extends nearly parallel with the Missouri, at a distance of 3 or 4 miles from it, to near 

sec. 8, T. 32 N., E. 3 W. At that point it turns abruptly southward to 

the southern end of the township and describes a broad semicircle, 

terminating at its eastern extremity in a high hill, about 6 miles west 

of St. Helena. From this point to Ponca it follows quite closely along 

the right bank of the Missouri, receding only near the more important
TODD.] ORIGIN OF LOESS. 101

valley of the Bow. This whole margin has more or less of a dentate 

character, the projections being high, narrow, and usually extending 

toward the northwest. The drainage of the loess from this edge west 

of St. Helena is southward without exception. This would indicate 

that in its earlier condition, if not at present, its northern edge was 

the highest portion. From this margin, especially from the vicinity of 

Santee Agency to St. Helena, the country descends abruptly from 100 

to 200 feet down to the Cretaceous clays, which occupy almost the whole 

surface between this line and the river, the only exception being where 

drift gravels extend northward from underneath the loess, as has been

Fio. 22. Section from Boonsboro, Iowa, to tho Missouri.

described in connection with the drift. The very striking features of 

this northern edge of the loess are seen in PI. XIV.

The altitude of the highest points is about 550 feet above the river. 

The thickness of the loess there varies from 30 to 100 feet. The eroded 

surface of the drift below was found at only one point, but so distinctly 

as to leave no doubt as to the fact. The branches of Bazile and Bow 

creeks have in many cases worn down into the underlying drift. But 

over much of the loess region one may travel for miles without finding 

a pebble. In Dickson and Dakota counties the loess covers the drift 

very perfectly, no pebbles being found even along streams that are 

eroded 200 or 300 feet below the general level. The loess in Lyon

FIG. 23. Section near south line of Carroll County, Iowa.

County, Iowa, sustains a very similar relation to the Big Sioux to that 

which it.has to the Missouri in northern Nebraska, but its edge is less 

elevated and somewhat less abrupt. Instead of being 550 feet above 

the stream it is not more than 250 feet.

Professors White and St. John noted a similar relation in central 

Iowa 1 . Figs. 22, 23, and 24 represent their conclusions.

In the southern part of Lincoln County and the northern part of 

Union County, South Dakota, the inner edge of the loess is very different from the points already described. Along the lower course of 

Brule Creek east of Vermilion Gap the loess occupies the hills on the 

east side, but as the moraine begins to appear on the western side it also

i See White's Iowa Keport, Vol. 1, p. 114; Vol. II, pp. 6, 98, 143.
102 MORAINES OP SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

appears on the west side of the creek and is spread out in shallow 

beds in an irregular manner upon its outer slope. Where the moraine 

consists of a few small hills about 9 miles east of Spirit Mound and 

just west of Brule Creek the inner range, rising 75 feet above the plain 

west, is very bowldery. The second range, about half a mile east, which 

rises 30 feet higher, has every appearance of being covered all over its 

summit with loess. No erratics were found, and badger holes showed 

only loess with calcareous concretions.

Southwest of Beresford, in the shallow cuts along the railroad, another 

opportunity was afforded to study this point. In the first cuts nothing

FIG. 24. Section near junction of Middle Eaccoon Kiver and Willow Creek, Iowa.

but pebbly clay or divsintegrated yellow till was seen below the soil, but 

about 30 feet below and about a mile distant from that town, which is 

upon the summit of the moraine, the loess begins to appear. In the 

first case it was in a portion of the cut covered with several feet of pebbly loam, which may be explained as a wash from the hillside west. A 

little farther east and 40 feet lower it showed its typical character, and 

began to cover the hills gradually toward the east. In Lyoii County,

FIG. 25. Sections at Sioux Falls, South Dakota.

Iowa, and Eock County, Minnesota, the drainage, as in northern 

Nebraska, is generally southward from the inner edge of the loess.

About Sioux Falls the loess occupies the hills in the bend of the Big 

Sioux. Underneath it lies darker clay, perhaps an old soil, below which 

are beds of pebble clay. When the loess was deposited the falls could 

not have been in existence. Some of the characteristic features may 

be seen from the sections shown in figs. 25 and 26. It is found rising
BULLETIN NO. 158 PL. y'V

'? ",''' "' // ^-$5$L-¥^ f^ ' ^^^''*^ ^^^'^^m^^M^'^M-p- '* if1l«i!«Safi

EASTWARD VIEW FROM NORTH EDGE OF THE LOESS SOUTH OF HERRICK, NEBRASKA.
TODD.] COTEAU DES PRAIRIES REGION. 103

about 75 feet above the Milwaukee station, or to an altitude of 1,455 feet 

above the sea, and is here again close to the exterior of the moraine 

This, though arrived at quite independently, corresponds well with its

FIG. 26. Sections at Sioux Falls, South Dakota.

altitude east of Beresford and at Warren, Iowa, and with the reports 

of Prof. K. H. Winchell respecting southeastern Minnesota.

COTEAU DES PRAIRIES REGION.

This region in some sense may be called the counterpart of the Red 

Lake region. It lies nearly in the same latitude, occupies an external 

angle of the moraine, and its features suggest lacustrine origin.

Boundaries of the Coteau region. The line of separation between this 

and the moraine on the west may be located as follows: From the 

vicinity of Brookings southwest to Madison, thence southeast to Hartford and the mouth of Skunk Creek, thence northeast along the north 

bend of the Big Sioux and east to Luverne, thence north to Pipestone, 

thence north and northwest to the vicinity of Brookings. The northwest boundary corresponds well with the northeast .course of Battle 

Creek, the southwest boundary, in general, with the west side of Skunk 

Creek Valley, the eastern boundary with more prominent outcrops of 

the Sioux quartzite.

Surface of the Coteau region. The surface may be described in general as a plain lying between the east side of the Dakota loop and the 

west side of the Minnesota loop of the outer moraine. This plain 

slopes toward the south at the rate of 4 or 5 feet per mile. Where 

crossed by the railroad between Pipestone and Madison its altitude is 

very uniformly 1,690 feet above the sea. Where it is crossed in its 

southern portion the altitude is from 1,460 feet north of Valley Springs 

on its eastern side to 1,575 feet on its western side near Hartford. The 

general elevation there can not be so accurately given because the plain 

has been very much eroded. As will be seen from the map, its southern portion is much traversed by streams, which have by their numerous branches quite destroyed the surface of the original plain, especially 

toward the southeast. On the other hand, the northern portion of the
104 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

plain, aside from the larger valleys and ancient'channels, rarely shows 

variation of surface of more than 10 or 15 feet. Ponds and shallow 

basins are found upon this plain in the vicinity of the moraine. More 

especially is this true west of Skunk- Creek and northeast of Madison. 

On the margin of the plain northwest of Pipestone, as it approaches 

the moraine, a few broad swells appear. Along the Split Eock are 

bowldery knolls, which rise above (?) the general surface from 25 to 50 

feet. The surface of the plain, where most even, is covered with a thin 

deposit of silt indistinguishable from loess. This was distinctly 

observed southeast of .Flandreau. It can scarcely be said to be general, 

however.

Northwest of Flandreau and Egan, lying in the great bend of the 

Big Sioux, is a plain lower and more even in surface than the one 

already described. It was traversed from the vicinity of Medary to 

Egan. Its western boundary has not been definitely determined, but 

must lie several miles west of that course. When this region was 

examined the atmosphere was so smoky as to prevent a determination 

of this point. It is possible that no distinct edge will be found, and 

that the plain gradually rises to the level of the one farther west i. e., 

the general surface of the region. The surface of this lower, plain is 

covered with silt, shows very few bowlders, and only a few quite shallow basins. Shallow sags also lead off into the short ravines running 

into the Big Sioux. The general surface is very even, and does not 

show elevations more than about 5 feet in height. Along the valley of 

the Sioux southward the-hills are much lower than farther back, and 

probably may, many of them, be found to correspond in structure as well 

as altitude to this lower plain. In a trip southwest from Dell Eapids the 

highest hills east of Skunk Creek are 1,590 feet in elevation, while west 

of Skunk Creek the general surface of the country rises abruptly to 

the higher plain at 1,675 feet above the sea.

Valleys of the Goteau region. The valleys may be divided into those 

which are now occupied by streams, which we may call recent valleys, 

and those which are not so occupied, which may be characterized as 

ancient channels. They are so-related to one another, however, that 

we shall treat them together. The principal streams of the region are, 

first, the Big Sioux, then its three principal tributaries, Battle, Skunk, 

and Split Eock creeks, and two smaller though scarcely less important 

ones Flandreau Creek, which lies in an old outlet channel, connected 

with Lake Benton in the Minnesota moraine, and Deer Creek, leading 

from another outlet in the same moraine. Both have large valleys, 

broad, flat bottomed, and with abrupt sides.

Battle Creek rises inside of the moraine, in Badus Lake, and first 

flows southeast through a broad valley, but after passing through the 

moraine turns sharply to the northeast. Its valley outside of the 

moraine is broad and marshy, arid, especially its eastern bank, is quite 

low, about 40 feet below the plain north at the bend. Its lower course
TODD.] VALLEYS OF COTEAU EEGION. 105

is occupied by open lakes. Leading southeast from near the bend in 

Battle Creek, and in line with its upper course, is a remarkable ancient 

channel, crossing the railroad a little west of Coleman. North of 

Wentworth it is occupied by a shallow lake 3 or 4 miles in length, 

which we will call Lake Wentworth. Farther east it becomes marshy, 

and the lower portion of this channel is occupied by a small branch of 

the Big Sioux. This channel, from its position, seems likely to have 

been once occupied by the stream which flowed through the gap in the 

moraine to the northwest and which later, turning northeast, began the 

valley of Battle Creek. Herman, Madison, Brant, and Skunk Creek 

lakes occupy a very remarkable valley. The first of these lakes lies surrounded by the moraine. There are numerous channels from the slopes 

of the moraine leading into it, some from the south, but the more 

important, which are now occupied by copious streams, from the west 

and north. The lake is a beautiful sheet of water, of somewhat crescent 

shape, and surrounded with quite abrupt hills. The peninsula from its 

eastern end is covered with trees. Leading east from this lake is a 

system of channels, of which there are two principal ones. One leads 

east and southeast from the north portion of Lake Herman to Lake 

Madison, thence southeast along the course of that lake and Brant 

Lake, gradually running out beyond. In this valley flows the stream 

which connects Lakes Herman and Madison. The other valley, beginning with the southern point, is not so deep and continuous at first, 

but is occupied by several smaller lakes and ponds, which lead to a 

distinct channel Avithin a couple of miles. It extends approximately 

parallel with the first channel, with which it connects now and then by 

cross channels. The series of marshes along the southwest side of Lake 

Madison lies in this channel, and south of Brant Lake it becomes the 

principal channel of the two and conveys the waters which flow from 

Lake Madison and Brant Lake, and which form Skunk Creek. The 

resemblance of Lake Madison to a mighty river is very striking. Its 

winding course and its alternation of abrupt banks and low bottoms 

with trees deepen the impression. In 1881 it first, to the knowledge of 

white men, began to flow out by a cross channel into Skunk Creek. 

The hills between these twin channels rise in some cases to more than 

100 feet, and have their full share of bowlders.

It is interesting to compare this channel with the Lake Wentworth 

channel. Both of them have a southeast direction, both are excavated 

in the higher plain of the region, and both seem to have had their 

lower courses changed at a subsequent stage. While the stream occupying the Lake Wentworth channel turned northeast, the one occupying Madison Lake channel turns southward. On the other hand, they 

differ in that the lake portion of Madison Lake channel was still occupied while that of Battle Creek channel was vacated. Hence we find 

that the Lake Wentworth channel is excavated only to the depth of 40 

feet below the plain, while that of Lake Madison is 100 feet below the
106 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

plain. It should be noticed also that the Madison Lake channel is 

mainly external to the moraine, while the other passes through the 

moraine. We may notice also a correspondence between these two 

streams and the two principal branches of Smith Creek, in the Bed 

Lake region.

The lower course of Skunk Creek lies in a broad, flat-bottomed valley with abrupt sides, and with its western bank, where it has been 

examined, nearly 100 feet higher than its eastern. Furthermore, the 

western edge of its valley is covered with bowldery knolls, suggesting 

a morainic origin; but more probably they are of the same formation 

as the bowldery osar-like ridges to be described in a future section.

Split Eock rises in Pipestone County, Minnesota, and flows south and 

southwest to the Big Sioux below the great bend. The most important tributary, which is in some sense the principal stream, is Pipestone 

Creek, which, rising near the same point, joins the Split Eock on the 

Minnesota line 6 miles south of the northeast corner of Minnehaha 

County. Its valley has been so affected by the red quartzite that it 

has been frequently wrongly mapped. In Palisade Township it passes 

through a narrow gorge about 4 miles in length. This is walled below 

on either side with perpendicular walls of quartzite. These rise about 

60 feet above the water, and the gorge in its narrowest place is about 

the same'in breadth. The confining of the stream by this rock has 

prevented the widening of its valley, as is frequent in other streams 

of the region. It is not probable that this gorge is mainly the work of 

the Split Eock, because its rocky sides are not continuous. They recede 

at many points some distance from the stream, and become buried by 

the drift. In such localities they are, nevertheless, cut into chimneys 

and cliffs, as though they were formed by some agency long before the 

later deposit, possibly by ages of weathering, perhaps by the action of 

the sea itself. Just below Palisade another tributary comes in from the 

north which has a wider valley, and on this account has had the credit 

of being the main stream. The exposure at Palisade has been well 

described by Mr. Warren Upham in the thirteenth annual report of 

the Minnesota survey. Considerable valuable information has also 

been given concerning this locality in the Fifth Annual Eeport of the 

United States Geological Survey, page 201. The plate facing that 

page, however, gives an exaggerated idea of the breadth of the gorge. 

As the treatment of the older rocks is foreign to this paper, the reader 

is respectfully referred to those works for further information.

About the center of Brandon Township is an exposure of diorite for 

some rods along the west bank of the Split Eock. 1 It is much decomposed and is presumably an intrusive formation. In sec. 23 the red 

quartzite is again exposed near the surface of the stream, with several 

feet of chalk stone (Mobrara) directly above it. The junction between

1 This is the rock which, since my examination of it, has been reported by Prof. W. H. Hobba to be 

divine-diabase.
TODD.] DELLS AT DELL EAPIDS. 107

the two, however, is not exposed. The numerous strise found upon the 

rocks in the localities mentioned, and others farther east, will be considered in detail in another section.

The Big Sioux enters the region under consideration near Brookings, 

in a valley from three-fourths to 1£ miles in width. Above the 

mouth of Battle Creek its valley is quite wide and about 140 feet 

below the high plain west, which is a narrow extension of that occupying most of the region. From that point to Egan it is bounded by the 

lower plain, which at the latter point is about 100 feet above the stream. 

This plain seems not to slope so rapidly as the stream, for at its upper 

end, near Madary, it is not more than 80 feet above the stream. The 

valley of the Big Sioux as a whole fails to present the abrupt sides and 

sharp edges which commonly characterize the other valleys of the 

region. A reason for this feature may be found in the check to its 

erosion by its crossing two important ledges of quartzite. One of these 

is at Dell Eapids. At Sioux Falls the course of the stream has been 

such that it has failed to excavate so deeply; probably the rock has 

not been so much exposed to erosion, for its surface is more than 100 

feet lower than at Dell Eapids, and the force of the stream has been 

expended over a much wider surface.

The Dells at Dell Rapids. There are three gorges at Dell Rapids; 

one is known as the Wet Dell, one as the Dry Dell,- and the third is 

the present course of the Big Sioux. The course of the stream at the 

rapids is nearly due west. The Wet Dell leaves the present channel 

south of the town and takes a south-south west direction for about 2£ 

miles, where it strikes the present channel again. It is filled with 

water through most of its course and might easily be taken for a stream 

that has been dammed. When the Big Sioux is flooded the water flows 

through this channel. The Dry Dell leaves the present channel near 

where it turns south and continues its course westward. It is of less 

width than the Wet Dell, but is filled with earth to within 12 feet of 

the top of the rock. Its western end is hidden under the hills forming 

the west side of the valley. The present channel has excavated the 

rock to less depth than the Wet Dell. There are two or three pillarlike rocks standing in the center of the stream to a height equal to the 

ledge at the side. One of these has been utilized as a pier for the railroad bridge. Below the Dells the hills along the Big Sioux Yalley are 

rarely over 80 feet above the stream. The surface of the quartzite 

above Dell Eapids is compact and even-topped, but shows few striae. 

East of the Wet Dell a few were found bearing S. 25° E. to S. 40° E. 

The red quartzite appears again about 4 miles west of Dell Eapids, 

where it is 100 feet higher than at Dell Eapids.

Below Dell Eapids the Big Sioux continues the general features of 

the valley above and keeps a straight southerly course to the southern 

point of the Great Bend at Sioux Falls, where it turns sharply, first 

northeast, and then northwest and north, falling over the ledge of
108 MORAINES OP SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

quartzite (a height of about 80 feet), and then continuing in a northeasterly course to the vicinity of Brandon, where it turns sharply to the 

south again, which course it keeps for some distance. The distance 

from its sharp south bend to its sharp north bend is 10 miles, directly 

northeast. The fall of the river through this region may be learned from 

the following elevations, derived from railroad levels. In each case the 

level of the water is given.

Elevations along the Big Sioux, showing grade of river. Feet.- 

East of Volga............................................................... 1,596

Near Egan.................................................................. 1,510

At Dell Rapids.............................................................. 1,476

West of Sioux Falls......................................................... 1,403

At the Chicago, St. Paul, Minneapolis and Omaha Railway east of Sioux Falls. 1,381 

At the Chicago, Milwaukee and St. Paul Railway............................ 1,369

West of Brandon............................................................ 1,281

East of Canton.............................................................. 1,217

Riverside near mouth....................................................... 1,079

Great Bend of the Big Sioux. The bend of the Big Sioux at Sioux 

Falls is remarkable in two or three particulars. In its present course 

it flows south to the north edge of the quartzite ledge, it would seem 

for the express purpose of forming a durable series of rapids for water 

power. The Sioux quartzite is exposed west of the city near the level 

of the stream, and east of the town over nearly the whole surface of the 

falls, which are more than half a mile in length. The neck separating 

the bottom land north of the town from the gorge northeast is considerably lower than the hills in the bend farther south, and is less than 

20 feet above the bottom land on the northwest. Its form and structure 

indicate that at one time the stream flowed across the neck. Why then 

did it not continue to do so and cut down through the till which probably 

forms the most of it? If it had done so it is probable that there would 

have been no falls; at least not until the river had cut back to the 

rock at Dell Kapids. (It may be that the quartzite occurs south of that 

place, but such is not known to be the fact.) The answer is believed 

to be probably the following: We have seen that there was much 

drainage from the ice sheet northward south of Sioux Falls, and when 

the ice occupied the outer moraine Skunk Creek was the channel by 

which all the Glacial streams from the vicinity of Volga to Sioux Falls 

found escape. Even supposing that the Big Sioux at that time took 

the shorter course, it is easy to see that the western side of the channel 

would be cut down most rapidly, and in this way the main channel 

would be drawn westward and southward until forced northward by 

the contact with the moraine and strong currents pouring over the 

lower portion of the moraine at that point. It may be stated here that 

while we have given, as we suppose, the immediate cause of the bend, 

the primary cause is to be found in the advance of the ice across the 

pre-Glacial course of the Big Sioux. No developments have been made
TODD.] KNOLLS IN THE COTEAU REGION. 109

to corroborate the supposition, but it seems not improbable that the preGlacial course of the Big Sioux may have been southward into the Vermilion, and that in the advance of the ice toward the east there may 

have been a damming of the streams coming from the north, and the 

formation of a glacial lake over this region somewhat as was conceived 

to have been formed in the Eed Lake region; with this difference, however, that while in the latter case it was of temporary duration, in this 

case the lacustrine epoch continued until the basin had become completely filled with drift material.

Bowldery knolls in tlie Coteau region. In speaking of the moraine, 

reference has already been made to systems of osar-like ridges found 

on its outer slope. These extend out upon the extramorainic plain, 

and we =will here give the more detailed description which has been 

promised. The system in this region which has been most closely 

observed is the one 5 to 6 miles northeast of Montrose. Its more prominent features are illustrated in Pis. IX and X.

The bowldery knolls are from 15 to 35 feet in height, and are arranged 

for the most part in a rude linear system lying in the bottom of a shallow valley which leads from a col or sag in the moraine eastward and 

southeastward to a branch of Skunk Creek. The head of the system, 

which begins quite gradually, lies along the north side of a channel-like 

lake half a mile long and perhaps a quarter as broad. This lake cuts 

the crest of the moraine transversely. As in the case of similar knolls 

near Crow Lake, the surrounding slopes are comparatively free from 

bowlders. Like that system, also, this one receives a branch which lies 

in a valley joining it from the northwest. The recency of the topography 

is attested by the occurrence of basins beside the knolls, which are yet 

undrained. The lake is about 40 feet below the highest adjacent point 

on the crest of the moraine, about 240 feet above the East Vermilion at 

Montrose, and 170 feet above the plain farther west. This system, like 

the systems in the Eed Lake region already referred to, lies above the 

level of the loess.

The interior of the knolls was nowhere exposed, hence we can say 

nothing of their structure from direct examination; but from their general appearance as compared with some which were excavated northwest 

of Waterbury, South Dakota, we should expect to find them largely 

composed of stratified material.

Along the western edge of Skunk Creek Valley, also, there are 

bowldery knolls which rise to the height of 20 or 25 feet above the 

ponds just west of them. Though these have not been connected with 

gaps in the moraine, their proximity to an important stream and their 

separation from the morainic hills farther west by a plain 3 or 4 miles 

in width, as well as their lower elevation, may be taken as evidence 

that they belong to the same class of deposits as those already mentioned.

Along the Split Bock are found systems of knolls which appear to
110 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

be of a rather novel character. They are of rounded form and are 

found in clusters rather than in ranges. The most important cluster 

that has been observed is about 6 miles southwest of Pipestone. They 

rise to the height of from 25 to 40 feet above the general level and nearly 

200 feet above the Split Eock southeast. They are arranged around 

the head of a valley leading into that stream. The slope of the southeast side of the valley, rising 120 feet, is wholly occupied with the red 

quartzite. There are about fifteen knolls in this cluster, and it occupies most of the surface of two sections. A few others are found along 

the east side of the Split Eock below the junction with Pipestoiie 

Creek, but they are found only in clusters of two or three. From their 

form and altitude they stand out conspicuously, although they do not 

attain the height of the first cluster, not rising generally more than 150 

feet above the stream. These, which are near Garretson, South Dakota, 

have been referred to on a previous page. All of these knolls present 

the same features. Their summits are covered with pebbles and a few 

small bowlders. Two exposures were examined which had been made 

by the opening of the summits of these hills for gravel and sand. 

Their interior structure, where examined, was found to consist of 

irregular layers of pebbly clay and stratified gravel and sand to a 

depth of 5 or 6 feet. Below that for 5 or 6 feet farther pure sand was 

found. Whether the sand comprises the bulk of the hill has not been 

learned. Their form and position suggest the idea that these hills 

were primarily dunes which have been thinly veneered with drift and 

somewhat shaped by aqueous and glacio-natant action. This is not 

easily reconcilable with the supposition that this locality has been 

swept very lately, if at all, by an ice sheet.

Hummocks in the Coteau region. At various points the red quartzite 

ledges present the peculiar phenomena which may most aptly be 

described by this term. The upper layer of the rock becomes bulged, 

and is heaved up in a domed or conical form to the height of 5 or 6 feet. 

These have been described by Prof. N. H. Winchell in his report on 

Eock County, Minnesota. The surface of the hummock is covered by 

these blocks in their natural order, but with the joints between them 

broadening more and more toward the center of the hummock. That 

they are of recent origin is indicated by the occurrence of striae around 

them, as if they were not in existence when the striation was in progress. Professor Winchell's suggestion that they may have been caused 

by ice i. e., alternate freezing and thawing with the change of seasons, 

aided by the force of vegetation and a little soil gradually getting into 

the openings seems quite plausible. They are apt to occur at equidistant intervals.

Striae in the Coteau region. The red quartzite, which is frequently 

exposed in this region, abounds in striae. They present several novel 

features. The striae are distinctly shown, rarely more than 2 feet in 

length and not often more than one-eighth inch in depth. They are
TODD.] STRIDE IN COTEAU REGION.

fl

commonly quite minute. They are frequently attended with crescentic 

cracks, whose ends incline toward the direction of movement. These 

are arranged parallel with one another at approximately equal distances. 

Systems of these are found with breadths of from one-half inch to 18 

inches, and may sometimes be 3 feet in length. The larger ones reveal 

more of a parabolic than circular form. In the larger systems the 

longer cracks are intercalated with the shorter ones, suggesting the 

coexistence of two systems of vibration. The general appearance of 

such a system is fairly represented in fig. 27 (1), which was carefully 

drawn from nature. Not 

infrequently the striae 

with which these crescents 

are connected have been 

worn away, and the crescentic cracks are the only 

record remaining of the 

original marking. The 

depth to which the cracks 

extend varies from the 

merest trifle to at least an 

inch, and it is not improbable that further examination may increase this figure.

The inclination of these 

cracks to the surface, near 

the axis of -the system, is 

forward, but gradually 

turns backward as the distance from the axis increases, until it may-incline quite strongly backward.

Besides these cracks, 

which are clearly referable to ice action, there are 

others resembling them somewhat, in which the crescentic marking 

turns in the opposite direction. These are also apt to show an equidistant arrangement, but are never as near together nor as regular in their 

shape and position as those already described. They may be ascribed, 

with considerable confidence, to the ripple marks preserved in the stratification of the rocks. Fig. 27 (2) shows a case where both these kinds 

of markings occur.

A careful study of the striae of this region shows more variation in 

direction than has been commonly ascribed to glacial action. This will 

appear from the table of striae given below; Not infrequently three or

FIG. 27. Various markings on Sioux quartzite.
112 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

four systems of striae, of widely varying direction, occur upon the 

smooth surface of the rock with equal distinctness. Some of the novelties which have been observed are shown in fig. 27. Curved striae not 

infrequently appear.

StricB found in the Coteau des Prairies region. 

[Corrections are made for magnetic variation.]

Locality. Direction.

Pipestone, Minnesota:

Near the Three Maidens...........

Near Pipestone Falls..............

Pipestone City

Three miles southwest of Pipestone-.. 

About 8 miles SSW. of Pipestone......

Four miles north of Palisade..........

Palisade:

At the southeast edge of exposure.

One mile east.....................

One and one-half miles south of Palisade. 

Two miles north of Valley Springs....

Northwest corner of Iowa ............

Opposite mouth of Split Rock:

Inside of the moraine. ............

One mile outside of the moraine .. 

Sioux Falls:

Near Milwaukee station ..........

East of Cascade mills (recent)....

Southeast of Queen Bee mill......

East of C., St. P., M. & 0. station 

Dell Rapids, east of Wet Dell.........

Four miles west of Dell Rapids.......

S. 30°-260-28°-400 W.

S. 14° E.

S. l°-190-240-270-280-370 W.

S. 0°-2°-3° E.

S.22°-230-250-260-320-37°-380 W.

S.34°-42°-38°-45° E. 

g. 3o_7o_13o E.

S. 22° W. 

S. 14°-18° E.

S.33°-38° E.

S.23°E.

S.13°-180-280-480-530-580-63° E.

S.8°-530-62°-630 E. 

S.80-90-130-160-180-190-23°-300- 

38°-53° E.

S.13° E. 

S.13° E.

S. 13° curving to 8° E. 

N. 28°-45° W. 

S.43°-53° E. 

E. [mag.]=S.88°E. 

S.13°-23°-28° E. 

 S.2° W.
CHAPTER IV. 

THE DRIFT REGION INSIDE OF THE OUTER MORAINE.

This is naturally divided into three principal parts: The second 

moraine, the region between the moraines, the portion inside of the 

second moraine.

SECOND OR GARY MORAINE.

Several circumstances combine to make the second moraine less 

prominent in height, in breadth, and in complexity:

(1) It was formed upon a nearly level plain left by the great ice 

sheet. There were therefore no very prominent features to distort or 

elevate the moraine, as was the case with the outer moraine.

(2) Anotber circumstance, which was also a result of its formation 

upon a plain, was its predominating tangential drainage. As the ice 

sheet retreated from the principal moraine, its edge in general withdrew to lower ground.. Hence while occupying the second moraine 

the waters tended to flow along its edge to the two principal streams, 

the James and the Yermilion. This tangential drainage tended to 

erode the moraine in some cases and to bury it in others.

(3) The ice sheet had probably diminished considerably in thickness, 

at least toward its lower margin; therefore its pushing power and probably its velocity had decreased. Both of these would diminish the 

amount of the material crowded into the moraine.

(4) It is not unlikely that the period of formation of the second 

moraine was much shorter than that of the first.

Northeast of Turtle Point 6 or 8 miles, and occupying the narrow 

space between Firesteel and Sand creeks, is a range of stony hills 

presenting the usual features of a moraine. It rises frequently to the 

height of 100 feet above the general level, or 130 feet above Sand Creek. 

Gravel and sand are very abundant, also bowlders of limestone and 

gray granite. Its extent northwestward has not been determined, but 

it probably is to be connected with stony knobs southwest of Wessington Station. From the before-mentioned locality northeast of Wessington Springs, the moraine extends in a discontinuous system of 

irregularly crescentic clusters of sharp knobby hills which are from 20 

to 60 feet above the very even plain. Their convexity is toward the 

west. The inner edge, along which the principal range lies, passes 3£ 

miles west of Woonsocket, where it rises to an elevation of 75 feet. It 

is there called the Pony Hills, which are sketched in fig. 28. The 

Bull. 158 8 113
114 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

ridge continues 4 or 5 miles farther, then disappears. At Twin Lakes 

another ridge rises to the height of 30 feet and continues south 2 

or 3 miles. Light bowldery ridges just east of the Firesteel in 

Jerauld County should doubtless be reckoned as portions of the second 

moraine.

South of Twin Lakes the principal development, which, however, is 

little more than a broad swell surmounted with a few bowldery knolls, 

passes 5 or 6 miles west of Letcher in a south-southeasterly direction 

to the Firesteel northeast of Mount Vernon. South of the Firesteel, in 

the northern portion of T. 103, E. 61, the surface rises into broken 

gravelly ridges extending in a southeastern direction. Between them 

arenumerousbasins elongated in a northwest-southeast direction, which, 

from their position and connection, suggest the action of a stream successively shifting from one to another toward the northeast. Possibly 

the Firesteel formed them after it entered the moraine and followed

FIG. 28. Pony Hills, near Woonsocket, South Dakota.

the retreating ice. Three or 4 miles west of Mitchell one of the more 

prominent valleys near the outside of the moraine connects with Enemy 

Creek. Four or 5 miles south of Mitchell are two ranges of long 

narrow hills, about 60 feet in height, lying west-northwest, east-southeast; these are known as Enemy Creek Hills (fig. 29). A view from 

them shows less conspicuous knolls in the plain to the southwest. 

These hills form one of the most prominent portions of the moraine. 

A peculiarity of their position is that they lie on ground lower than 

that a little northeast of them. One mile east of the junction of the 

Firesteel and the James is a very conspicuous hill, locally known as 

Medicine Hill. It rises about 210 feet above the James River, and 90 

feet above the general level of the lacustrine plain surrounding it east, 

north, and west. A range of low hills extends south from it and curves 

to the southeast. It is evidently the head of an iuterlobular moraine, 

which became nearly a glacial island during the latest occupation of 

this moraine.
TODD.] COURSE OF SECOND MORAINE. 115

West and southeast of Eockport the banks of the James show several stony knobs. These are especially numerous in the northern portion of T. 101, E. 58. It would seem that here, near sec. 2, was the apex 

of a reentrant angle of the moraine. Extending from near sec. 33, 2 

miles «ast of Eockport, in an east-southeast direction, is a long, shallow, ancient channel, now occupied by a miry slough 2 or 3 miles in 

length. This is at a level of about 110 feet above the James. About 

one-half mile east of the river bluffs at Eockport it makes a slight 

bend from a south-southwest direction, which is about in line with the 

upper portion of Pierre Creek, to a southeast direction. This part of 

its course is among very gravelly knobs, rising about 40 feet above it. 

Among them along its west side is a line of small kettle-hole ponds 

nearly parallel with it. It continues south to the ravine of a small

FIG. 29. Enemy Creek Hills from the northeast, v Enemy Creek.

creek which connects with the James. This channel seems to be a 

trace of the internal drainage of this angle of the moraine.

In or near sec. 33, T. 101, E. 58, is a cluster of morainic knobs which 

give an extensive view of the plain to the east, although not apparently 

up to the level of the land west of the James. Southeast from this 

point the inner edge of the moraine extends quite directly to Wolf 

Creek, 2 or 3 miles above its junction with the James. Along considerable of this portion there is found just within the moraine a chain of 

shallow sloughs and ponds, the moraine itself appearing somewhat like 

the edge of a terrace rising 40 or 50 feet above these ponds.

In or near sec. 4, T. 99, E. 58, is a cluster of high stony knobs interspersed with deep ponds, some of them covering several acres. These 

seem to connect in a semicircular curve of low and scattered domes 

with the high knolls near sec. 33, before mentioned. The moraine has 

not been definitely traced farther east of James Eiver.

The line described thus far is clearly the inner limit of the moraine, 

comprising some of the last-formed ridges. It should be remembered 

that the retreat of the ice sheet had from the nature of the case been
116 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

more rapid on the west, hence the ridges are more scattered. Other 

knolly areas which should be correlated as earlier-formed members of 

this moraine may be mentioned as follows: !

Several miles of knolls along the east side of the Firesteel, about 10 

miles west of Woonsocket; another, similarly related to the .same 

stream, 12 miles west of Letcher; a broad strip 2 or 3 miles east of 

Mount Vernon, extending southeast to Enemy Creek a few miles west 

of the before-mentioned Enemy Creek Hills; light ridges 2 to 3 miles 

north of Olivet, trending east of south. Possibly the stony hills east 

of Olivet and those northeast of Scotland are a modified portion of this 

moraine, but more likely they are of an osar nature. Then, on the 

north and east of James Ridge the moraine appears again, first feebly, 

but rising quite markedly as it turns east across the James in the 

southern border of T. 95, Es. 55 and 56, being specially prominent a 

few miles south of Walshtown. Thence northeast for a few miles it 

failed to form, probably because at that time the main drainage was in 

that direction rather than in the line of James Eiver. In the southeastern part of T. 96, E. 55, it gradually rises again.

About 8 miles southeast of Menno is the rather abrupt southern end 

of a morainic ridge, which extends northward and circles round the 

northwestern extremity of Turkey Eidge, from which it is separated 

by a broad, shallow valley. In this valley are the head waters of Clay 

and Turkey Eidge creeks. Having passed about halfway between 

Freeman and Childstown the moraine takes a turn more to the east 

and crosses the West Yermilion halfway between Marion Junction 

and Parker. Through this portion of its course it may be described as 

a broad, even-topped swell, rising about 50 feet near Menno, 140 feet 

near Freeman, and 75 feet near Marion Junction, above the plain to the 

northwest. Its inner surface slopes rather abruptly. Its outer slope 

declines very gently. This latter character is best developed southwest of Parker.

One of the most conspicuous points of this moraine is found in sec. 

2, T. 99, E. 54, close to the valley of the West Yermilion. It rises about 

160 feet above the stream and about 75 feet above the general level. 

From this point the moraine keeps a course about midway between the 

East and West Yermilion east of Canistota and northward. While 

both inner and outer slopes are encroached upon and modified by the 

drainage into the Yermilions, the summit shows numerous ponds, and, 

at intervals, low stony knobs. The gap through which the West Yermilion passes is quite narrow, with abrupt sides. Five miles west of 

Montrose the moraine is a simple continuous low swell, a little roughened 

on its summit. Shallow basins are more numerous on its outer slope 

and summit. Along its outer foot they form a connected chain in a 

shallow sag running parallel with the moraine. The summit rises 45 

feet above the plain outside and 30 feet above that within.

Similar features characterize it also east and northeast of Howard,
TODD.] REGION BETWEEN MORAINES. 117

except that rather conspicuous knobs appear here and there, and it 

approaches more closely to the East Vermilion, its crest being a little 

west of Winfred. A remarkable line of broad ponds, just east of the 

summit of the moraine, extends for 10 or 15 miles parallel with the Bast 

Vermilion and 2 or 3 miles west of it. This corresponds to the smaller 

one before noted west of Montrose.

REGION BETWEEN THE SECOND AND PRINCIPAL MORAINES. 

GENERAL CHARACTERISTICS.

This region differs from that outside the moraine in several wellmarked particulars:

(1). First and most prominently, in the absence of erosive topography, 

the streams traversing it being usually limited to narrow channels with 

abrupt sides. There is little or no trace of watersheds. One does not 

dream of the nearness of a stream till he comes upon the immediate 

edge of its channel.

(2). The surface everywhere manifests what may be called a sinkand-swell topography. Sometimes the swells or low ridges are much 

elongated, and have a general trend somewhat like the waves upon the 

sea. At other times the elongated character is not prominent where 

there is an indiscriminate mixing of low, rounded domes with shallow, 

circular basins.

The amplitude of undulation, or the ratio of the difference in altitude 

between the tops of the hills and the bottoms of the depressions to the 

distance between hilltops, varies greatly in different portions. In 

many cases it may be 5 feet to a mile or a mile and a half. Perhaps 

nowhere in the whole area under consideration is it more than 40 feet 

to a half mile, and examples of this extreme occur but rarely.

(3). Nothing like buttes is found in this region. While this is true 

in general, there are inequalities of great extent, probably due to preGlacial topography, which will be mentioned as we describe the area 

more in detail.

WESTERN REGION.

Under this head we would include all of the country lying west of a 

line running north from the Ohoteau Creek Hills to the moraine and 

outside of the latter. This has an oblique, fan-like form, with its narrow or handle portion extending northward, east of Turtle Ridge, and 

drained by the north branch of the Firesteel.

Where this widens, south of Turtle Ridge, there begins a valley 

extending southward which is now occupied by the upper portion of 

the West Firesteel, then with White Lake and the valley of Pratt 

Creek. This valley lies approximately parallel with the moraine west 

of it. Although through the most of its course it now contains but 

little water, it bears evidence of having been at some time occupied by
118 MORAINES OP SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

a stream approaching the James Eiver in size. The watershed between 

White Lake and the West Firesteel is very low. One would suspect 

on first sight that the drainage from White Lake was into the Firesteel. 

Pratt Creek in its lower portion, near Castalia, has eroded a valley over 

200 feet in depth, along which are immense beds of gravel and numerous 

bowlders.

South of the Firesteel the general level gradually rises to an altitude 

of over 1,500 feet at Plankington and beyond 9 or 10 miles, where the 

country begins as gradually to slope southward, forming a broad, low 

swell running east and west, which displays an amplitude of undulation of 5 feet to the half mile. Upon its southern slope lie the deep 

valleys of Andes and Wet Choteau creeks. About their upper courses, 

in the vicinity of Grandview, the surface of the country is unusually 

rough, the amplitude being from 35 to 40 feet to the half mile. The 

general level of the country gradually rises again as it approaches the 

moraine southwest, but it does not extend to the moraine, for from the 

vicinity of Pratt Creek to the Choteau Creek Hills there is a broad shallow valley extending parallel with the moraine, which seems to have 

been formed by the flow of water toward the principal outlets. This 

valley near the southwest end of Andes Lake is over 300 feet below 

the general level of the country south. It is occupied by the tributaries 

of Pease Creek, by the upper portion of the creek flowing through the 

Andes Lake Outlet, and by the middle course of Choteau Creek. Elsewhere, also, there are dry channels extending through it, which are 

probably filled with water in springtime.

Aside from the variations in level which have already been alluded 

to, there is a more general slope of the whole area toward the east. 

Yorktown is 230 feet above Mount Vernon, according to railroad levels, 

which indicates a slope of 10 feet to the mile; yet no one in traversing it 

would speak of it as other than a very level plain. An indication of a 

similar slope is derived from a preliminary survey between Chamberlain and Springfield. About 9 miles northwest of Lake Andes the 

altitude is 1,665 feet, also by railroad levels, while in Lower Choteau 

Creek Valley, likewise inside the moraine, it is 300 feet lower.

More evidence of this eastward slope and of its probable recent 

origin is seen near White Lake, and also near Lake Andes, in the apparent change of drainage in recent times. As before mentioned, White 

Lake and the upper portion of the West Firesteel lie in the same 

valley. The country east is level and much lower than the country 

about Plankington. Evidently the drainage of the region was at one 

time southward into Pratt Creek. Such must have been the case until 

the ice sheet had receded nearly to the second moraine. At that time, 

or possibly considerably later, the drainage from the southwest Wessingtons and Turtle Eidge turned eastward, beginning the West Firesteel. This may, it is true, indicate nothing more than "the withdrawal 

of the ice, without change of slope.
TODD.] REGION BETWEEN MORAINES. 119

At Lake Andes the evidence seems more strongly in favor of the recent 

tipping of the region. Extending southwest from the southern end of 

Lake Andes through the gap is a water course less than 10 feet above 

the water in the lake, which appears as though it had been recently 

occupied. Southeast from the central portion of the lake extends a 

long narrow slough, connecting, it is believed, with Wet Ohoteau Greek. 

That this is the fact is not certainly determined. Its occupancy by 

water for several miles in that direction has been observed. The natural 

suggestion which comes to mind in considering this case is that the 

plain about Lake Andes has been tipped toward the east, so that its 

western outlet is now dry, and its waters are seeking drainage toward 

the southeast by what was, perhaps, formerly a tributary of the lake.

Other reasons for believing in a recent westward elevation of the 

country will be considered further on. This case is more significant than 

the last because we can hardly explain the westward flow by the occupation of the eastern outlet by the ice, as in the previous case. We 

see no reason for supposing that the ice would linger longer in the 

lower Choteau Yalley than near the Andes Lake Outlet, but contrariwise.

Ancient lakes. In this western region certain areas bear evidence 

upon the surface of lacustrine origin. These are found, as before stated, 

in the valley of the West Firesteel, which may be considered as a former extension of White Lake. Another is found southwest of Mitchell, 

extending from the second moraine southward to the vicinity of Plainview. In both these regions the surface is very level, there being little 

or no trace of the undulating surface usually found upon the till. Crossing T. 100, E. 62, on the borders of this lacustrine area are two or three 

light and disconnected lines of low stony ridges suggestive of morainic 

action, but possibly due to thrusts of ice against the shore. Along the 

western border of this latter lacustrine area rise Pony Creek and Twelvemile Creek, which flow eastward to th« James, in valleys resembling 

those already described.

Ancient channels. Besides the ancient valley of Pratt Creek and 

that lying inside the moraine from the Cedar Creek Hills to Choteau 

Creek, which have been mentioned in our general description of the 

country, there are several minor ones which are not so closely connected with the general topography.

A channel extends in T. 104, E. 63, from the Firesteel to the origin of 

Enemy Creek. In sec. 34, T. 102, E. 61, a narrow channel with abrupt 

sides and 40 feet in depth leaves the north branch of Enemy Creek and 

extends southeast to a branch of Pony Creek. The verification of this 

last statement was kindly accomplished by Mr. Gr. W. Bailey, who lives 

in the vicinity. As this lies in the lacustrine plain before mentioned, 

it indicates a flow of water around the ice sheet subsequent to the stage 

in which the lake was formed, a relation which reminds us of what was 

found in the Eed Lake region. Again, a channel extends in T. 98, B. 59,
120 MOKAINES OP SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

from Dry Creek to Lone Tree Creek, and the lower course of Dry Creek 

connects with the mouth of Pony or Twelvemile Creek. By these channels the drainage of the west side of the glacier was effected during the 

time of the formation of the second moraine, as shown in Pis. XV and 

XVI. ,

Wells. With regard to the structure of the drift formations throughout the area, considerable light has been derived from wells and other 

excavations. In general, the structure seems to be, as usual, upon glaciated surfaces. First, there is a layer of yellow pebble clay from 10 to 

30 feet thick, which passes below insensibly into blue pebble clay, or 

frequently there is a layer of sand between them.

Along the foot of Turtle Eidge the drift seems unusually thin. The 

Cretaceous clays are reached within 15 to 20 feet of the surface. Near 

White Lake the drift is much deeper more than 50 feet at least. 

Near White Lake Station several wells of considerable depth were 

dug, none of them reaching through the drift. The town well was 90 

feet deep, most of it being through blue clay. No water had been found 

when visited. Fragments of wood were found at a depth of nearly 80 

feet. One, apparently a root, was over a foot in length and 3 inches in 

diameter. Generally there is found in that vicinity first 40 feet of yellow 

clay, then 30 feet of blue clay, then a layer of sand, then blue clay again. 

Water has not been found except in the yellow clay in basins. At 

Plankington there is first usually 75 feet of yellow clay, then 55 feet 

of blue clay, then chalk or shale containing water. Near Grandview, 

wells, which are usually dug in basins, are about 10 or 12 feet in depth. 

A well dug in town upon the hilltop, I was reliably informed, was 150 

feet deep and had failed to reach water. All below a few feet of yellow 

clay at the surface was blue clay. Sixty feet of it was dug, the rest 

bored. No trace of pebbles was found in the last 10 feet. At Mount 

Vernon a well 108 feet deep, and containing 52 feet of water, was dug 

through 40 feet of clay, the rest being chalkstone. This chalkstone 

appears on the general slope of the country 2 or 3 miles west of Mitchell. 

It also appears in natural exposures near the general level 10 miles 

southwest of Mitchell, in ravines connected with Enemy Creek; also 

near the bottom of the valley of the Firesteel northwest and north of 

Mitchell, and in a ravine southeast of that place. This chalkstone, 

which before weathering is bluish, and is then sometimes called soapstone, has been struck in wells 8 miles north of Grandview. At Castalia, on a low bottom, of Platt Creek, wells 25 feet deep bring to the 

surface mostly blue pebbly clay. At Plainview wells 44 feet deep were 

mostly in blue pebbly clay and furnished poor water. At Emsley postoffice, a little west of Plainview, a well was observed about 50 feet in 

depth, which showed little but pebbly clay and very little water. Several 

miles southwest of Plain view a well 30 feet in depth showed mostly 

blue pebbly clay, but at the bottom a thin layer of sand and gravel, 

below which there was apparently shale.
U.S.GEOLOGICAL SURVEY BULLETIN NO. 158 PL.XY

'.'i 1 1 1 ', '. \\\VA\ 7 \\\\ \\\\v\

ICE SHEET OCCUPYING

THE

PRINCIPAL MORAINE

A.Hoen X. Co. tilll .Bnlli
TODD.] REGION BETWEEN MORAINES. 121

In the western portion of the region now under consideration traces 

of wood have been frequently reported as found in wells. Most of 

them seem likely to be of the sort already mentioned as having been 

found 'in the well at White Lake, which, probably is a relic of preglacial or circumglacial forests.

An ancient tamarack swamp. Near Grandview, in the southeast 

quarter of sec. 33, T. 100, B. 64, were found traces of more recent occupation of the region by trees. In a well which had been dug on the 

edge of a basin near a branch of Andes Creek at the depth of 20 feet 

was found a layer of muck several inches in thickness, in which were 

pieces of wood with numerous fresh-water shells of nearly a dozen 

species. But the most remarkable thing was the stem of a hemlock or 

tamarack about 10 inches in diameter lying across the well, and in the 

muck were numerous cones evidently of the same species. Overlying 

this trace of a tamarack swamp was mud of various colors and consistency, evidently washed from the surrounding hillsides. That it 

should be so deeply buried was chiefly explained by its connection with 

the channel of Andes Creek. This was conclusive evidence that the 

region had been occupied more or less by timber since the ice had covered the region, possibly while the second moraine was in process of 

formation. Similar finds are reported from wells several miles west of 

that place. 1

Spotted surface of the country. One peculiar characteristic of the 

surface of the country about Plankington and west is the occurrence 

"of patches of clay spread irregularly in the black loam, which is the 

usual soil upon the drift, and in this portion still forms most of the 

surface. These clay patches are very irregular in shape and in depth. 

In wet weather they are very soft and miry, and in dry weather very 

hard and frequently seamed with mud cracks. They are usually covered with what is commonly called alkali grass (Triticum repens), which 

in the latter part of the summer is dead, while the blue joint and other 

grasses upon the loam are still green.

In a few shallow cuts near Plankington it was noticed that the clay 

extended in a horizontal direction and that it and the loam were 

coarsely interstratified. It is possible that this peculiar character of 

the country is due to its having been occupied by shallow waters from 

which clay and loam were precipitated somewhat as clay and sand are 

deposited upon bars along the Missouri at the present time. Another 

explanation may be found to meet some cases better, viz, that the clay 

patches are due to masses of Cretaceous clay carried along bodily by 

the forces of the glacier and deposited as bowlders which have afterwards been flattened out. Another and perhaps more probable 

explanation is that alkaline waters continuing in the depressions 

have dissolved the silica.

1 Professor Call determiues the fresh-water shells abouuiling in the muck as follows: Lymnophyia 

palustris Say, L. decidiosa Say, Gyraulus parvus Say, Valvata sincern Say, Segmentina armiyera Say.
122 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

JAMES VALLEY.

This valley occupies the portion between the moraines from the east 

side of the region already considered to Turkey Eidge, where the two 

moraines are in contact. The western portion of this region resembles 

that already described. Perhaps little need be added concerning it. 

Most of it is nearly level. The exceptions are found near the larger 

streams and in the vicinity of the principal moraine, particularly near 

the head of the interlobular portions. We have already noticed the 

rougher portion, which appears along the eastern rim of the semicircular 

valley around Ohoteau Creek Hills. With the rough area near Grandview this may indicate that the ice sheet had a faint tendency to form 

a moraine between the principal and second moraines. Another somewhat exceptional feature is the occurrence of ponds and lakes in unusual 

numbers along a line running west from Lesterville for 10 or 12 miles. 

The principal streams of this region are Einanuel Creek on the west, 

James Eiver near the center, and Clay Creek on the east. Emanuel 

Creek, west of Scotland, flows in a wide valley about 50 feet below its 

eastern rim and at a level higher than the plain a few miles east. Near 

its mouth it occupies a narrow valley 125 to 150 feet deep. The James 

River has a valley with abrupt stony sides and from a quarter to half 

of a mile in width. Its depth at Milltown is about 115 feet; northeast 

of Scotland, about 150 feet. Clay Creek occupies a broad valley near 

the moraine, which evidently at one time was the principal outlet from 

the ice sheet. This valley near the moraine is 50 to 75 feet in depth 

below the plain northwest. The tributaries of these streams have cut 

down to the same level near their junctions, and occupy narrow valleys 

with abrupt sides throughout nearly their whole course. They rise in 

basins or shallow winding valleys. Through the dry seasons they consist of chains of deep pools, with little or no running water between.

Exposures of older roclcs. Along the James Eiver we discover again 

many natural exposures of older rocks. The chalkstone of the Niobrara is exposed on the banks of a small stream near Scotland, about 

75 feet below the general level. Forth of Milltown for several miles 

the Dakota sandstone occupies both banks of the James, rising 40 or 50 

feet above the stream. At Eockport is an extensive exposure of Sioux 

quartzite covering several hundred acres, and just above it, on the east 

side of the river, there is chalkstone in several localities. Along Enemy 

Creek both the Dakota sandstone and the red quartzite are exposed, 

but the latter was too low to be touched by the glacier. The chalkstone shows conspicuously along Clay Creek 120 feet above the stream 

and about 50 feet above the general level of the plain west. It is 

also widely exposed along the Firesteel and the channels to the south, 

including Enemy Creek, as far west as Mount Vernon.
U. S. GE OLD GI C AL SURVEY BULLETIN" NO. 158 PL.XVI

i I ' ''a -' < \ ' < !' i

' \ \ \\''\\

\ \ i i \ > i \

i ' \ \ ' >V

^

CE SHEET OCCUPYI NG

THE

SECOND MORAI N E

BY J. E.TODD
TODD.] REGION BETWEEN MOEAINES. 123

VERMILION VALLEY.

This region resembles the western region in outline, except that its 

fan-like portion is more extended toward the southeast. Its narrow 

part, corresponding to the handle of the fan, is occupied by the valley 

of the East Vermilion. The general slope of the whole surface is 

toward the southeast. This is indicated by the present direction of 

the streams, and there is no evidence of a change of course, as in the 

western portion of the region between the moraines. There is little 

trace of lacustrine action except along the Lower Vermilion, and this 

evidently was greater during the recession of the ice than while the 

second moraine was forming. Along the east side of Turkey Eidge 

numerous narrow northwest-southeast valleys indicate the action of 

running water during the earlier recession of the ice. About Swan 

Lake, in Turner County, occupying an east-west strip 3 or 4 miles in 

width, is a rough portion showing many low stony hills and ponds. 

This continues northeastward past Lenox, and may be correlated with 

the trace of a minor moraine before noticed. The average altitude of 

this, strip is not greater than the country north and south of it. North 

of Swan Lake, about Turkey Eidge Creek, the country is unusually 

flat and clayey, forming the broad shallow valley of Turkey "Ridge 

Creek, which is the principal tributary of the Vermilion.

The East Vermilion and Vermilion form the principal stream of this 

region. The East Vermilion occupies a deep valley just inside the 

outer moraine. West of Madison it is about 200 feet below the summit 

of the outer moraine and about 90 feet below the high swell just west 

of it, which farther south is the second moraine. In its upper portion 

it displays a very bowldery terrace along the inside of the principal 

moraine.

Below the mouth of the West Vermilion the stream passes through 

a broad basin-like valley, perhaps once a lake, till it approaches Turner 

or Davis, its immediate valley being only 15 to 25 feet deep. Near 

Turner its channel cle'epens to 35 feet, is about 50 feet a little north of 

Lodi, 60 feet at Bloomingdale, and over 80 feet at its mouth. The broad 

plain along its lower course is very level and even. It extends with 

similar characters through the principal moraine and terminates as a 

terrace of the Missouri Eiver.

There is no distinct watershed between the Vermilion and the Big 

Sioux. The plain reaches through to the Big Sioux without much variation in level. There is probably a very slight slope to the southeast, 

but railroad levels scarcely show it. The course of the streams in that 

direction seems more the result of their following back the ice sheet in 

its recession.
124 MORAINES OP SOUTHEASTERN SOUTH DAKOTA. [BULL. 158. 

REGION INSIDE THE SECOND MORAINE.

This portion of our field has a very even surface. From the inside 

of the second moraine west of the James the surface extends eastward 

as almost a dead level to the west side of Miner County, where it 

begins to rise gradually toward the east, and so continues in that direction to the second moraine on the east. This eastern portion presents 

the usual. topography of slight swells and basins, with the further 

modification of broad shallow valleys running southward. These are 

occupied by various branches of the Vermilion and the James. Beginning on the east, we have the West Vermilion Eiver, Wolf Greek, and 

Eedstone Creek.

Upon the level portion of this region the streams take a southwest 

or southeast direction, as the case may be, to the James Eiver. The 

whole of this region, except it may be a small portion north of Woonsocket, presents the features of an ancient lake bed filled with drift 

deposits. Its boundary, so far as yet ascertained, lies close along the 

inside of the second moraine from the vicinity of Woonsocket to Medicine Hill. This line passes a mile or so west of Letcher, through 

Mitchell, where, however, it is obscured by knolls, thence curving east 

and northeast around the foot of Medicine Hill. From that point it 

curves southeast for a few miles, then around again to the northeast 

and north, and passes about 2 miles east of Diana, and continues north 

indefinitely. It seems not improbable that this ancient lake extended 

as far north as Lake Tchanchicaha. This conclusion is strongly sustained by railroad levels. According to the Chicago, Milwaukee and 

St. Paul survey the altitude of the station at Mitchell, which is a little 

below the general level, is 710 feet; Letcher, 713 feet; Mellette, which 

is 100 miles farther north and again on the level of the lake-like plain, 

712 feet; Warren, 713 feet; Aberdeen, 715 feet, while in the region now 

under consideration, Diana, which is near the eastern boundary of the 

lake, is 727 feet. These altitudes are above Lake Michigan.

The general surface shows a thio covering of silt, but bowlders and 

pebbles are found a little below the surface. Along the west side of 

the area there is an old channel, now a marsh called Long Lake, which 

extends from 2 or 3 miles east of Woonsocket southward to the vicinity 

of Letcher. Along this marsh and south to Mitchell the surface and 

subsoil are sandy. Probably this same sandy strip extends northward 

along Sand Creek, but this has not been ascertained. Around Forestburg, according to report, the sand has collected in well-developed 

dunes. A portion may be kames. The James Eiver has cut a narrow, 

sharp-edged valley through this plain. It is 50 feet below the level of 

the plane near Huron, 60 feet at Forestburg, 75 feet east of Letcher, 

and 90 feet east of Mitchell.

This lake seems to have been for the most part filled to the level of its 

surface, but south of Diana (Artesian), and north of Letcher, peculiar
TODD.] REGION INSIDE SECOND MORAINE: 125

depressions were noticed which may be most readily explained by supposing that the lake at that point was not filled. The surface presents 

low mounds and broad ridges, irregularly arranged and in some cases 

isolated, interspersed with shallow marshy basins from 10 to 15 feet 

below the general level. The mounds between in no case rise above 

the general level. A ready explanation is that they were at first occupied by ice blocks, while d6bris from the rapidly melting ice sheet buried 

them and leveled the general surface. In other words, the region is a 

"pitted plain," with the "pits" unusually large and confluent.

Flowing wells. A remarkable feature of the region is the existence of 

flowing wells in the vicinity of Diana and Forestburg. These are invariably obtained by boring through the till, which is about 100 feet in 

thickness, to a layer of gravel lying underneath. Sometimes thin layers 

of sand are struck, in the till. The flow is abundant and rises to about 

15 feet above the surface at Diana. At all points below that level, as 

far as has yet been found, flowing wells may be obtained. The most 

trustworthy and explicit accounts were obtained from Mr. C. J. Croninger, of Diana (now called Artesian). Similar conditions are found near 

Forestburg, but have not been so carefully examined. At Letcher, also, 

a flowing well was drilled, but the water was obtained from a much lower 

stratum, probably the Dakota sandstone. It was at a depth of more 

than 335 feet. This well was a pioneer of the deep artesian wells that 

now abound in this region. It was drilled about 1884. A description 

of the well, furnished by Mr. H. M. Hopkiris, who had charge of its 

boring, is as follows:

Well section at Letcher, South, Dakota.

1. Deep soil.

2. Yellow clay.

3. Sand, 1 foot.

4. Blue clay, containing a layer of sand 1 foot thick; this extends to a depth of 

100 feet.

5. Gravel and quicksand of several feet.

6. Soapstone, 75 feet, with some slate.

7. Sand rock to the bottom, 335 feet deep.

Cause of Lake Dakota. The reason why this area was not opened 

at its southern end so as to prevent the accumulation of a body of 

water may be traced to the configuration of the bottom when left by 

the ice sheet, and the failure of the ice to excavate toward the south is 

readily explained by the extension of the red quartzite across its path. 

This barrier may be conceived to have so checked the ice as to increase 

the height of its surface and the erosive action below, just as is the 

case with a stream in similar circumstances. It would have also 

increased the velocity of subglacial streams, and in this way may have 

tended to accumulate masses of gravel. The sandy region along its 

western side, together with the ancient channel, now a marsh, may be 

referred to the more recent occupation of that side by the stream, or 

to the currents flowing through when the lake was filling.
126 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

Buried wood. From several localities reports have come of fragments of wood found in wells. But while suspecting that a deposit of 

this material might be discovered in the lake, after diligent inquiry in 

several cases, facts were not found to favor such a conclusion. The 

fragments were isolated, only a few inches in diameter, and occurred 

at different depths.

Strice icithin the moraine. The region within the second moraine contains extensive exposures of red quartzite which present in a striking 

manner the abrading action of the ice. In the following table is presented the more striking observations which have been made. At the 

westernmost exposure of the red quartzite no striae have been found, 

and the occurrence of the Dakota sandstone several feet higher in its 

close vicinity indicates that it was not subject to the action of the ice.

Striae found within the second moraine. 

[Corrected for magnetic variation.]

Locality.

Rockport:

By the schoolhouse at west side 

of valley .......................

Farther east......................

Seven miles north of Alexandria ......

Pier Creek, 5 miles north of Alexandria. 

Wolf Creek, 6 miles east of last.......

Wolf Creek, southwest of Bridgewater.

Direction.

S.22°-49°-51°-57° E.

N.89°E.=S. 78° E.

S. 51°-59°-65° E.

S. 2°-100-20°-220 E.

S. 14°-17° E.

S.8°-12c-170-22°-29°-32°-370-420-

49°-57° E. 

S. 12 W. S. 12°-150-17°-190-210-

22°-27°-29°-39° E.

Only one locality is found between the moraines, viz, 2 miles east of 

Parker, where the direction is S. 52° E.

The exposures in this region are rather extensive, the one at Rockport covering more than a square mile. It affords comparatively few

strise, because of its

s weathered character.

By far the finest locality 

for its display of distinct 

and vared striae is southwest of Bridgewater, 

where many are several 

feetin length (PL XVII). 

They show curves and 

crooked lines of remarkable form. One was noted 12 feet long, 2 

to 3 inches wide, and about one-fourth inch deep. The crescentic 

cracks are also finely exhibited; a system 18 inches wide and 3 feet

Pig. 30. A. gouge from quartzite exposure, near Bridgewater, 

South Dakota.
U. S. GEOLOGICAL SURVEY

PHOTOGRAPH OF STRI/E ON QUARTZITE NEAR BRIDGEWATE
REGION INSIDE SECOND MORAINE. 127

long was noted, and they occur of all sizes from that down to an inch 

in width. A roche moutoune'e about 10 feet high and with several nondescript figures pecked upon its surface, stands by the creek near the 

center of the valley. Toward the westernmost exposure of-the quartzite 

is a peculiar spoonlike gouge in the rock, evidently formed by the ice, 

at least smoothed and shaped by it. Its edge toward the north is quite 

complete, sharply defined, and curved like the point of the bowl of a 

spoon. Its southern edge is lost in the lower surface surrounding. 

The portion corresponding to the bowl of the spoon is regularly but 

slightly concave. The outer surface of a surrounding rock rises gently 

toward the riin before described. The subjoined sketch illustrates it 

better than words (fig. 30).
OHAPTEB V.

TERRACES OF THE MISSOURI AND BIG SIOUX, AND 

HYDROLOGY OF THE REGION.

These have an important bearing upon the glacial history of the 

region, as they record more or less clearly the variations in level of 

.streams attending the Glacial epoch and subsequent to it. They form 

perhaps the clearest evidence attainable in our field concerning the 

movements of the earth's crust and the meteorological conditions during 

the epoch. This evidence is the more valuable because it is in great

measure independent of glacial deposits. / ' . TERRACES OF THE MISSOURI AND ITS TRIBUTARIES.

These readily arrange themselves in three groups: The silt terraces, 

the lower bowldery terraces, and the higher bowldery terraces.

SILT TERRACES.

The silt terraces are chiefly distinguished by the fineness of their 

material and their markedly lower elevation. They do not rise anywhere higher than 100 feet above the present stream, and are usually 

much lower. Although covered with silt, they are not entirely composed of it, but often especially the higher ones are composed largely 

of Cretaceous clays in situ.

The survey of this group of terraces has been necessarily very incomplete. The number of observations taken is far from sufficient to prepare the way for a thorough discussion of them. The attention of the 

writer has been more turned to the bowldery terraces, which are more 

intimately connected with glacial phenomena. In general it may be 

said that there are two silt terraces which lie above high-water mark 

of the present time and which may be traced at most points favorable 

for their preservation. The difficulty of correlating them arises from 

their higher elevations in the vicinity of tributaries and the occasional 

interpolation of subordinate terraces.

At the Great Bend (PI. XVIII) the higher terrace upon the right side 

of the river lies from 90 to 100 feet above low water. It is extensively 

developed in the bend 5 in fact, with the lower silt terraces it occupies 

the whole area of the bend north of its neck. This bend describes a 

circuit of 30 miles, returning to about 2£ miles from its beginning. At 

this locality is well illustrated the principle that a continually cutting 

stream forms a slope on the inside of a bend, which shows no break

128
U. S. GEOLOGICAL SURVEY BULLETIN NO. 153 PL. XVIII

GREAT BEND OF THE MISSOURI RIVER FROM THE EAST. 

A neck of Pierre clays, which, if cut through, would shorten the river 20 miles, v Missouri River, vv Bowldery terrace.
TODD.] SILT TERRACES OF THE MISSOURI. - 129

unless the course of the stream is at some point turned against it. 

Hence we find that this upper terrace grades down insensibly to the 

lower terrace in this slope, which is 7 or 8 miles in length. On the 

eastern side of the neck, where the measurements already given were 

taken, the lower silt terrace is from 30 to 70 feet higher than the river, 

while the present flood plain is only 10 to 18 feet above. On the opposite side of the river the higher terrace extends as a plain from 2 to 3 

miles in width from the Great Bend to Crow Creek Agency and beyond. 

Its elevation above the river at the upper end is from 90 to 108 feet. 

Near Crow Creek Agency, where Soldier Creek enters from the northeast, it is from nearly 110 to 200 feet, while the bottom lands upon 

which the agency buildings are located is about 15 feet above the 

river.

At Chamberlain the lower terrace, upon which the town is built, is 

well represented, and shows, away from the mouth of American Creek, 

the Niobrara chalkstone occupying most of its height. It slopes from 

about 70 to 50 feet. Along its outer edge are a series of short, sandy 

spurs which rise to 125 feet. They may be part of a delta of American 

Creek. The lower terrace is narrowly developed along American 

Creek. Across the river, above Chamberlain, we again find the higher 

terrace well developed, from 40 to 70 feet in height, and traces of lower 

terraces also occur.

At Lower Brule Agency a lower terrace, about 45 feet in height, is 

well developed, the upper terrace being traceable also north of American Crow Creek, and back and south of the agency it is from 60 to 70 

feet in height. Lower than the terrace upon which the agency is 

situated is a narrow flood plain, covered at high water. The higher 

terrace may be traced down the river as follows: It is faintly developed 

below the mouth of White Eiver at an elevation of 50 feet. Opposite 

Brick Kiln Buttes it is narrowly developed and is about 80 feet high. 

Below the mouth of Snake Creek a high terrace appears sloping from 

a rather indistinct line about 150 feet above the river down to 50 feet, 

where it ends in a conspicuous edge. This is probably to be attributed 

to the rapid cutting down of the lower bowldery terrace through the 

narrows above Wheeler. At Mill Head Point, about 10 miles above 

Wheeler and on the opposite side of the river, it is about 75 feet in height. 

It is traceable north upon the opposite side of the river, and 2 or 3 

miles south on the same side. At Wheeler there is a terrace upon 

which the town is built, about 45 feet above the river. The fine terrace upon which Fort Eandall is built is from 30 to 35 feet above the 

river. At Niobrara the new town is built upon an extensive terrace 

about 25 feet above the river. No purely silt terraces higher than from 

15 to 20 feet are noticed along the river farther south.

The lower terrace is represented again west of Brick Kiln Buttes at 

30 feet and at the same level at Eosebud Landing. Below the mouth of 

Snake Creek it is not represented, unless in a broad bottom sloping from. 

Bull. 158 9
130 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

about 25 feet down to about 10 feet. At Mill Head Point it is sharply 

shown at 45 feet. At Wheeler a terrace of considerable width rises 

about 18 feet and continues some distance eastward along the north 

bank of the river. A similar terrace, though narrowly developed, rises 

about 15 feet at Fort Eandall, and is much wider on the opposite side 

of the river at White Swan. Farther down this seems to disappear or 

to be indistinguishable from the flood plain, which at Niobrara rises 

from 10 to 15 feet above the river, and about the s.ame height farther 

down. This lower terrace is almost purely sand and dark loam ; the 

higher terrace, as before stated, frequently has a Cretaceous base, and 

at some points, as at Wheeler and Fort Eandall, considerable gravel 

and bowlderets are found in its lower portion.

LOWER BOWLDERY TERRACES.

Just north of the narrowest portion of the Great Bend rises a high, 

broad, butte-like hill. To the north it is bounded by the silt terrace 

already described. At the south a low ragged ridge of Cretaceous clays 

connects it with the main bank. Its surface, where least eroded, is quite 

even. It rises 235 feet above the river. Its whole upper surface is 

covjered with bowlders and gravel mixed with yellow clay.

With a glass the hills to the northwest across the river were discovered to be also bowlder clad. Upon the east side of the bend the highland, curving sharply up against the river, shows no drift. No trace of 

bowldery hills similar to the one described is found till Soldier Creek 

is crossed, north of Crow Creek Agency. There a range begins which 

extends southeast across Campbells and Elm creeks to the vicinity of 

Crow Creek. These hills are more or less detached from the highlands 

north by erosion. East of Campbells Creek they rise to 320 feet above 

the river. A well-defined bowldery terrace was noticed along Boxelder 

Creek 12 miles farther east, rising to the height of 125 feet above the 

stream. It is estimated to be 15 or 25 feet above the bowldery terrace 

east of Campbells Creek. South of that point this terrace is remarkably developed about the junction of Boxelder Creek with'Crow Creek. 

It was also examined between the lower courses of Crow and Smith 

creeks, where it is mostly a barren plain of gravel. ,

In the vicinity of Chamberlain the extensive series of old channels 

and terraces which have been noticed in our consideration of the Bed 

Lake region are found at a height of 200 feet above the river. This 

includes an old channel cutting across the northwest corner of T. 103, 

E. 71, leaving an ancient island west of it, and also the channel from 

American Creek southwest to the Missouri, in which lies Eed Lake, 

(PI. XY). At about the same level is a broad, well-developed terrace 

lying along the north bank of the Missouri for 2 or 3 miles above its 

junction with White Eiver. Along American Creek above Pukwana is 

an old lake bed at the same altitude, which is probably a portion of the 

old Eed Lake channel. The terraces and channels show much gravel in
TODD.] BOWLDERY TERRACES OF THE MISSOURI. 131

their upper portion, though covered with 10 or 15 feet of loess-like silt. 

An imperfect exposure in a ravine northeast of Ancient Island before 

mentioned, which is opposite Lower Brule Agency, is as follows:

Exposure northeast of Ancient Island, South Dakota.

Ft. In. 

Gravel and sand, horizontally stratified ..................................... 8 0

Laminated clay, showing ripple marks ...................................... 1 2

Gravel and sand, arranged in short crescentic patches, showing oblique stratification (torrential)....................................................... 10 0

This exposure is about 50 feet below the bottom, of the old valley, and 

does not, therefore, include the covering of silt observed elsewhere.

In the vicinity of Chamberlain, also, the prevalent altitude of the 

bluffs along the river is from 325 to 350 feet. Their tops are quite uniform and little eroded. They are capped with 40 to 50 feet of drift, 

which passes into a layer of loess probably from 5 to 15 feet in thickness. The bluffs, across the river especially, have the appearance of a 

terrace. North of American Crow Creek a bed of gravel was found 

capping the edge of the terrace-like bluff 315 feet above the Missouri. 

It corresponds in level to the gravelly drift already mentioned as quite 

extensive on the south side of that stream. The top of Ancient Island, 

opposite Lower Brule Agency, rises 300 feet above the river. Between 

the lower course of the White River and the Missouri extends a siltcovered plain which averages about the same elevation. A terrace 

occupying the first bend in the Missouri to the south, and also a portion 

of the second in the same direction, is estimated to be at the same 

altitude. The lower gravelly plain south of White Eiver seems to 

be only a little more elevated (350 to 400 feet), and probably belongs 

to the same formation. Perhaps some of it is a little more ancient.

Along the narrow channel directly southwest of the Bijou Hills I 

failed to observe any trace of this terrace, but west and northwest, back 

of the silt terrace already mentioned, it is widely developed as a sloping 

terrace from 95 to 175 feet high. It presents the usual features of 10 or 

15 feet of loess-like silt above a heavy deposit of bowlders and gravel. 

In the valley of Pratt Creek, near its mouth, and developed extensively 

along the Missouri, is a bowlder-topped terrace 330 to 360 feet above 

the latter. A view of it from the south led to the belief that it was 

originally connected with a high terrace at Mill Head Point, which 

rises 250 feet above the river and rapidly declines toward the south. 

This latter terrace exhibits a remarkable quantity of bowlders in its 

upper portion, the coarseness of material apparently diminishing down 

the stream. Its structure is finely shown by a ravine crossing it a 

little below Mill Head Point. Its upper surface was originally covered 

with 10 to 15 feet of loess-like silt, which has been removed near the 

edges and along the ravines.

At Mill Head Point there is an extensive bowlder bar, reaching well 

out into the river, which at that point runs like a mill race. I was
132 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

informed that the river survey developed the fact that the river about 

2 miles north of Wheeler was paved with bowlders. 

. Back of Wheeler is a broad terrace rising at its southern edge about 

150 feet above the river. This presents a deep gravel bed, with bowlders 

in its upper portion and covered with loess-like silt about 10 or 15 feet 

in depth. North of Fort Eandall, at the junction of the Andes Lake 

Outlet with the Missouri, a broad, sloping terrace lies at an altitude of 

120 feet at its inner edge (PI. XIX). Farther back it connects with the 

mouth of Andes Lake Outlet at the altitude of 200 feet. In this terrace the Cretaceous shales rise to the height of 90 feet. At Greenwood 

the terrace upon the north side of the river at its edge rises to an altitude of about 180 feet, presenting characters similar to those already 

mentioned. This terrace continues, with a breadth of from 2 to 4 miles, 

along the north side of the Missouri to the mouth of Choteau Creek. 

It presents a beautiful fertile plain, quite even except where traversed 

by the three or four creeks which flow in deep, narrow valleys. The 

edge of the terrace back of Greenwood is 175 feet high; east of the 

creek near by, 140 feet, and 6 or 7 miles east in a similar locality, 200 

feet. The remote edge of the plain east of Grass Lake Outlet is 240 

feet, and about 5 miles northeast of Greenwood, where the ancient 

bank rises abruptly 75 feet above it, it is 250 feet above the river to the 

south (PI. XX). North of Eunning Water this terrace fills the bend in 

the Missouri from the mouth of the Niobrara to Springfield, with an altitude quite uniformly of 200 feet. It constitutes the first bench north 

of the town of Niobrara. more than a mile in width, and is continued 

up the Niobrara Eiver, first in the sharp south bend near its mouth, 

then extensively on the south side of the river up for 15 or 20 miles. 

This terrace is also well developed along the east side of Bazile Creek.

Farther east, along the south side of the Missouri, the surface has 

been so modified by erosion that little trace of terrace formation could 

be expected and none was noticed. In the valley of Weigandt Creek 

southeast of Herrick, Nebraska, there is an extensive terraced surface 

rising at some points about 325 feet above the Missouri. There was 

much difficulty, when first examined, in correlating it with other 

deposits along the Missouri. But further study led to the satisfactory 

conclusion that it was formed by Weigandt Creek and its tributaries. 

It rises from 175 to 200 feet above that stream. It presents the usual 

features of a gravelly terrace, with the silt covering scantily formed. 

Similar deposits are found along the neighboring stream, called 

Beaver Creek.

At Yankton, on the north side of the river, the outer slope of the 

moraine, as was noticed in the valley northwest of the town, is quite 

gravelly about 130 feet above the river. Passing north from Tankton 

3 or 4 miles, we reach a broad terrace south of another of the numerous 

Beaver creeks. This is at an altitude of 120 feet above the river and 

connects with the broad valley south of Lesterville. Though the
U. S. GEOLOGICAL SURVEY BULLETIN NO. 158 PL. XIX

^FIA " r"'l '*P¥$f//>' "^ ",\\\ Wf^f^' '^/

LOWER BOWLDERY TERRACE, OPPOSITE FORT RANDALL.
TODD.] BOWLDERY TERRACES OF THE MISSOURI. 133

terrace seems mostly covered with pebble clay or loess-like silt, on the 

slope south of Utica considerable gravel was noticed.

At Vermilion the principal terrace, which is 6 or 7 miles wide and 

extends eastward to the Big Sioux, is about 80 feet above the river. 

It shows its structure to be pebble clay, with its upper surface eroded 

and capped with silt.

Below the mouth of Floyd River, near Sioux City, is a terrace 115 

to 150 feet high. It is composed of coarse sand below and of loess-like 

silt in the upper two-thirds; no bowlders.

In the vicinity of Herman, Nebraska, a terrace begins which continues past Blair to De Soto, about 10 miles in length and in places 

nearly 2 miles in breadth. This rises 100 feet above the river. At 

Fort Calhoun a similar terrace extends 5 or 6 miles. An obscure one 

about 60 feet in height is found at Omaha. At Bellevue, north of the 

mouth of the Papillion River, is another well-developed terrace from. 

60 to 70 feet above the river, and a similar one is found below the 

mouth of the Weeping Water at Wyoming.

We have already briefly described the extensive terraces along the 

Platte and Elkhorn rivers which rise to a level of 80 feet near their 

junction.

The valley of the White River approaches that of the Missouri in 

size, and is likewise mostly excavated from the Cretaceous clays. The 

alluvial bottoms rising about 20 feet from the bottom of the river form 

a more prominent feature, usually occupying most of the space in the 

deep bends in the river. Rising abruptly from this alluvial plain are 

bluffs of shaly clay over 100 feet in height. At an altitude of about 

130 feet is a well-defined gravelly terrace containing mostly western 

gravel. This seems to be excavated out of the Cretaceous, which 

appears again back of it and rises abruptly to the edge of a higher 

terrace about 200 feet above the stream. This terrace in one place 

shows alluvial deposits 30 or 40 feet in depth, exhibiting loesslike silt below, including about its middle a dark carbonaceous layer 

like an old soil. It is capped above, first with gravel, then with 

bowldery clay, which slopes with a gentle rise backward from the 

river to a height of about 260 feet. At the height of about 325 feejt 

another gravelly terrace appears, containing northern erratics and 

limestone and granite bowlders like the last. This seems to be continuous with the sheet of gravel south of the river, which has already 

been described.

COMPOSITION OF LOWER BOWLDERY TERRACES.

Thus far we have treated only of the external appearances of the 

lower bowldery terraces. We now proceed to give what light has been 

found concerning their internal structure and composition. There has 

already been given an imperfect section, which is found opposite the 

Lower Brule Agency. Apparently, although not certainly, the pre-
134 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

vailing structure is somewhat as follows: Ten to 15 feet of silt, passing 

abruptly into stratified sand and gravel, which is coarse and bowldery 

near the top, and finer and more evenly stratified below, the depth of 

the sand corresponding to the inequalities of the deposits below. In 

some cases the upper portion of the gravel is more or less occupied 

with till of reddish or yellowish color.

At White Swan and below, the Mobrara chalkstone and Pierre clays 

rise over 100 feet, forming a very substantial base for the terrace. 

Above these there seems to be a heavy body of till, but it is nowhere 

well exposed. Seven miles east of Greenwood the Cretaceous clays 

appear to rise over 150 feet, and shallow exposures exhibit red till above 

for 30 or 40 feet, and a mantle of silt of variable thickness over the 

whole. Between that point and the mouth of Choteau Greek the terrace is much eroded, but little or no trace of sand is found. The phenomena of soil and topography seem best explained by supposing that 

the body of the terrace is largely composed of Pierre clay.

Opposite Niobrara is a very complete exposure of the terrace, which 

is as'follows:

Exposure opposite Niobrara^, Nebraska.

Feet. 

Loess-like silt............................................................... 10-12

Eed clay, imperfectly stratified, which abounds in pebbles and bowlders..... 35

Fine sand, thinly stratified, w ith no trace of northern erratics............... 55

Imperfectly exposed ........................................................ 45

Niobrara chalkstone........................................................ 70

Level of the river.

The sand in this section seems identical in structure and composition 

with that observed at the Devils Nest and north of Coleridge. While 

there it is at an altitude of from 350 to 400 feet above the river, here it 

is below 150 feet. Still, its freedom from northern erratics would seem 

to indicate its pre-Glacial deposition. Moreover, it has less altitude 

than the Cretaceous rocks in this same terrace farther west, and the 

red clay at this point seems to correspond to that at Greenwood, both 

in altitude and in time of deposition. On the whole, therefore, it seems 

not improbable that the sand was deposited by the Niobrara, possibly 

in Lake Cheyenne, before the advent of the drift.

At Vermilion a combined section is as follows:

Section at Vermilion, South Dakota.

Feet. 

Loess-like silt, straticulate...... .............................. .............. 15-20

Till, eroded on top, yellow and compact above, and composed of irregular 

patches of gravel, sand, and red and blue till below....................... 40-50

Unexposed ................................................................. 20

Level of the river.

This composition may be referred to material brought down by the 

Yermiliou Eiver, at first laden with ice blocks, or in part to the direct 

action of the extension of the Vermilion lobe of the ice sheet. On 

either supposition a deep preglacial valley at this point must be 

postulated*
0. S. GEOLOGICAL SURVEV BULLETIN NO. 158 PL. xx

LOWER BOWLDERY TERRACE, FROM THE OLD BANK NORTH OF GREENWOOD, SOUTH DAKOTA 

v Missouri River, vv Bioad, shallow, channel-like slough.
 i ODD.] BOWLDERY TERRACES OF THE MISSOURI. 135

Three miles southeast of Blair the structure of the terrace is finely 

exposed in a number of deep ravines which cut through two-thirds of 

its height. They show nothing but rearranged loess, with an occasional thin streak of gravel in its lower portion. A similar composition is evidently true of the terrace at Fort Calhoun and also at Bellevue, except that its base is occupied by Carboniferous limestone. In 

each case the composition is referred to the numerous high loess bluffs 

in the close vicinity and along the river above, with comparative 

absence of drift.

The terraces along the Platte and Elkhorn have apparently very 

uniform structure, which consists first of silt, then of fine sand, passing 

below into fine sand and gravel. The evidence from deep driven wells 

shows that below the first gravel is a thick continuous layer of clay, 

below which is another heavy deposit of gravel. These lower layers 

extend underneath the whole valley so far as is known. Northwest of 

Fremont an exposure showed as follows:

Exposure northwest of Fremont, Nebraska.

Feet.

Loess-like silt ............................................................... 30-40

Fine sand................................................................... 30-40

Unexposed....................................-.........'..:................. 20

Level of bottom laud, which is probably 10 to 20 feet above the level of tb river.

North of North Bend was found from 5 to 15 feet of silt, according to 

the undulations of the surface, and sand rising from 75 to 80 feet 

above the river. The upper surface of the terrace shows gouges and 

imperfect channels, as if formed by strong currents.

From the foregoing presentation, particularly if reference is made to 

the table on a subsequent page, it appears that, above the narrows 

above Wheeler, there are two series of terraces mentioned under 

this head, one 100 to 150 feet above the other; also, that they come 

together below Wheeler. That they do not mark stages of the river as 

widely separated as their altitudes might seem to indicate may be 

inferred from the following considerations: The lower seems in places 

to be continuous with the bottom of old channels, as that of Red Lake, 

and east of Ancient Island, as though it corresponded to the bottom of 

a stream, while the upper series seems to slope gradually up into the 

surrounding country, as though it might mark the margin or flood plain 

of the ancient stream.

HIGHER BOWLDERY TERRACES.

These are the least easily recognized of all. This is not surprising 

when we remember that they are much the most ancient. Their high 

elevation, together with the unusually loose character of the strata 

upon which they rest, lead to the same result. Moreover, if the river 

was largely lacustrine when they were formed, as we are disposed to 

believe, its existence will only occasionally be evidenced by deposits 

adjacent to the present stream. They may have the various forms of
136 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL, 158.

beach or bar and delta as well as river terrace, according to circumstances. Little time has been given to their study, and the few observations incidentally made are given for what they may be worth.

Near the summit of the high hill south of the Bed Lake Outlet, on 

the side next to the Missouri, gravelly deposits were noticed at the 

altitude of a little more than 425 feet, which may be correlated with 

the higher portion of the gravelly plain just mentioned. Along Snake 

Creek, near its mouth, an extensive sloping terrace is found, with its 

usual bowldery gravel covered with silt and rising 330 to 417 feet above 

the river. Besides these in the Bed Lake region, we have nothing to 

suggest a terrace deposit below the trace of a water level around the 

Bijou Hills and the bowldery and gravel-topped hills 5 or 6 miles 

southwest of the mouth of White Biver, which are believed to mark 

the highest reach of the Missouri since its beginning.

Five or 6 miles east of Wheeler the outer face of the moraine shows, 

at the different points, the gravelly edge of a terrace at an altitude of 

over 400 feet. At Fort Band all, on the south side of the river, is a 

well-defined terrace, with its inner edge having an altitude of 415 feet. 

Northeast of Fort Bandall, near the moraine, is a similar well-defined 

edge of a terrace 420 feet above the river, which slopes gently up to 

450 feet. On the north side of the river northeast of Greenwood the 

surface is too low to exhibit any trace of a water line at this level. 

Opposite the mouth of the Niobrara the outer surface of the hill which 

forms a fragment of the moraine shows, a little below the summit, 

abundant gravel and sand at an altitude of about 400 feet above the 

river.

Between the Mobrara and Bazile Creek and along the Missouri east 

of the Bazile is found a wonderful development of gravel capping the 

older deposits in a terrace-like form at an altitude of 415 to 475 feet 

above the river (PI. XXI). It is observed to extend several miles 

south, and, as has been described under the head of the loess region, 

there is abundant evidence to show that this gravel formation extends 

underneath the loess indefinitely. It may not be called a terrace, yet 

the gravel exposed along the north edge of the loess, between it and 

the fine sand below, seems probably to belong for the most part or 

entirely to the same formation as the terrace described. Toward the 

east side of the Santee Beservatiou the gravel seems to have been separated into an upper and a lower member. The lower portion extends 

like an eroded terrace at the height of 390 feet. We have provisionally ascribed this phenomenon, on another page, to undermining. It 

will be remembered that this gravelly drift extends, with declining elevation, nearly to Dixon County. So far as has yet been discovered no 

trace of terrace at a corresponding altitude has been noticed below 

that point. It corresponds in elevation with gravel beds observed 

several miles up the Niobrara and with another near Plain view, 

Nebraska. Both of these show only western gravel.
U. S. GEOLOGICAL SURVEY BULLETIN NO. 138 PL. XXI

UPPER BOWLDERY TERRACE SOUTHWEST OF SANTEE AGENCY, NEBRASKA, 

v v Volcanic ashes in road.
TODD-l HEIGHTS OP TERRACES OF THE MISSOURI. 137

Table of heights of the terraces along the Missouri from the Great Bend southward, 

[r indicates the right bank, and I the left.]

' Locality.

In the Great Bend r...... .......

Three miles south of ChamberNorth of American Crow Creek r.

South of mouth of White River r. 

South of Red Lake Outlet I .....

West of Brick Kilu Butter. .....

Bijou Hills L.. ...... ...........

Near mouth of Snake Creek 1. . . . 

Near inouth of Pratt Creek I ....

Mill Head Pointr...... .........

Four miles east of Wheeler I ....

Greenwood r ...................

Silt terraces.

Feet. 

10, 18, 30-70,

90-100 

90-100

15, 110-150

. 8-10, 30-70

15-30,50-80,

120-125 

75-80

a 70-80

10, 20-40, 60-70

a 50

«10

15, 30-50

15-20, 65-75

10, 20, 50-150 

90-126

45,85

5,9-18,45,85-105

40-75

a 10, 25

15, 30, 40-45

5, 10, 20

10,30

10, 25, 70

10-15, 20-25

10-20

a 10

a 10, 20

Lower bowldery terraces.

Feet. 

235

200-250, 320

325

325

200, 350

315-320

200, 300

300

250 

a 200

90-175

330 

300-350

200-250

a 135-175

125-190

180-240

200-250

200

180-210

120-140

80-100

90-110

a 100

50-70

Higher bowldery -terraces. 

Feet.

350-400 510 

450-460

590

417

410-430

350

415

a 400

415-450

450-475

a Estimated.

The different levels under the head of " lower bowldery terraces" probably do not mark two stages of the Missouri, widely separated, as might5 

be inferred, for the upper one appears to have been marking generally 

the surface or flood plain of the river, while the lower in many cases seems 

from its configuration in some places to record the bottom of the stream.
138 MORAINES OP SOUTHEASTERN SOUTH DAKOTA. [Bou,i58. 

TERRACES ALONG THE BIG SIOUX.

As the Big Sioux is the counterpart of the Missouri in its relation to 

the moraine, so we should reasonably expect a system of terraces along 

it resembling that already described along the Missouri. From its lower 

altitude, more open valley, and less volume of water, we are prepared 

to anticipate lower floods and' less corrosion, and consequently less difference in altitude between the terraces. Another important circumstance acting iu the same direction is found in the greater hardness of 

rocks over which it flows. But without anticipating too much, we will 

proceed to examine the few traces of terraces which have been noted. 

It should also be acknowledged that the examination of this stream 

has not been so complete as in the case of the Missouri.

Above Sioux Falls the depth of the immediate valley of the Big Sioux 

is from 80 to 100 feet below the adjoining hills. Its sides are less abrupt, 

and the whole appearance is that of a stream in its middle course. 

This may be explained by the check given to its erosion by the ledge 

of Sioux Falls and higher up by the rock at Dell Rapids.

SILT AND LOWER BOWLDERY TERRACES.

At Egan, besides the immediate flood plain, which is quite low, is a 

terrace along the north side of the valley with its inner edge about 30 

feet above the stream. About a mile and a half northeast of Egau, in 

the edge of a gravelly terrace, the following section was noticed, beginning 30 feet above the river:

Section northeast of Eyan, South Dakota.

Feet.

Soil...................."....................................................... 1*

Loess-like clay, with, small pebbles and chalky points .......................... 1

Roughly and indistinctly stratified gravel, its upper half clayey, yellowish tint;

lower, more sandy ....................................-.............- ..'-..... 7£

Coarse sand, with scattered pebbles, obliquely stratified, iu eight layers from 1 to

8 inches in thickness......................................................... 5£

At Sioux Falls, as has been before stated, there is a very gravelly 

terrace extending from near the top of the falls down the river to the 

vicinity of Braudon, which is shown by railroad levels to be about 80 

feet above the stream at that point. A little below the mouth of Split 

Eock Kiver the elevation of the wide bottom along the east side of the 

Big Sioux is from 35 to 50 feet above the stream. Its altitude here is 

possibly due to ledges of red quartzite exposed a short distance below. 

At Kruger's mill, about 6 miles northeast of Canton, the terrace lies on 

both sides, but best developed on the east side, about 50 feet above the 

stream, and presents au interesting deposit of sand and gravel in its 

upper portion. The gravel presents the flow-and-plunge structure, and 

through it a fault was noted of a few inches throw extending vertically. 

At Canton several alluvial terrace edges are shown along the sides of
U. S. GEOLOGICAL SURVEY BULLETIN NO. 168 PL. XXII

\'. :*.'**'%£ .'-*

' ' "" ' V \-i ~\?T^$Ppi

DIG SIOUX RIVER NEAR FAIRVIEW, SOUTH DAKOTA. 

v Principal moraine, y Plain inside, vv Highei bowldery terrace. vvv Lower bowldery terrace.
TODD.] TERRACES OF THE BIG SIOUX.

the valley. There are but two, however, that are clearly distinct; 

the first is from 10 to 20 feet above the stream, the second about 40 

feet. The edge of the plain northwest shows a terrace edge, usually 

with much gravel at exposed points. This is about 125 feet above the 

stream. .

In the narrow portion of the valley between Beloit and Fairview 

(PI. XXII) is found a very interesting terrace of unusually bowldery 

character, which seems to correspond with the plain northwest and 

just north of the north end of the moraine, which occupies Highland 

Township. This plain, it will be remembered, corresponds in height 

with, or is a continuation of, the plain west of Canton, upon which 

Worthing and Leuox are situated. This terrace, 2 miles northwest of 

Fairview, is about 90 feet above the stream, and presents a furrowed 

appearance, as though eroded by streams flowing in the same direction 

as the present stream. These furrows and low places correspond with 

a second terrace, which is about 4f foet above the river. Opposite 

Fairview the whole surface has declined to that altitude. Back of 

Fairview a faint terrace edge was noticed at a height of 50 feet. 

Northeast of Austin this same high terrace is traced, presenting similar characters, at an altitude of 60 to 75 feet above the stream. Just 

north of Hudson, on the west side of the Big Sioux, is a gravelly terrace utilized by the railroad company as a gravel bed. Its upper surface is about 60 feet above the stream. The surface of this terface 

appears to decline rapidly toward the south. It is not difficult to 

correlate this series of terraces with the lower bowldery terraces along 

the Missouri. A well-developed gravelly terrace is found on the south 

side of the valley above Lake Madison, rising about 80 feet above the 

lake, and along east of Skunk Creek, southwest of Dell Eapids, a terrace, apparently of silt, rises to the height of 40 feet.

HIGHER BOWLDERY TERRACES.

The first and most remarkable examples of these are the high gravel 

hills northeast of Sioux Falls which, as was stated on a preceding page, 

rise about 210 feet above the stream. Near Kruger's mill, it will be 

remembered, there is a high terrace, with its inner edge about 160 feet 

in height, while farther south an exposure showed a stratified structure 

like that of a terrace at the height of 108 feet, and a gravelly line at a 

height of 180 feet. West of the stream a very bowldery edge, like that 

of a terrace, was noticed at a height of 120 feet, which is a little above 

the plain west. East of Canton the gravelly deposits shown in railroad cuts extended from about 100 to 175 feet above the stream. North 

of Fairview, and also east of the same place, a gravelly edge appears 

on the side of the bluffs at the height of from 200 to 220 feet. West of 

Calliope the hilltops, which are doubtfully referred to a terrace, are 

about 125 feet above the stream.
140 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158. 

TERRACES ALONG OTHER STREAMS.

There are few other streams in the field under consideration which 

are outside of the moraine. Those of this class in Iowa have not been 

studied with care, but most of them show high terraces of silt second 

bottoms, as they are popularly called which often serve as favorable 

locations for towns.

Striking examples of prominent terraces corresponding to those along 

the Platte and the Missouri below Sioux City have been uoted along 

the Boyer at Dunlap and Logan, the Nishnabotany at Harlan and 

Atlantic, the Little Sioux at Cherokee, etc.

PRESENT SLOPES OF THE MISSOURI AND BIG SIOUX.

From railroad levels and the Government survey of the Missouri we 

obtain the following:

Low-water slopes of the Missouri and the Big Sioux.

Missouri: Feet per mile. 

Pierre to Chamberlain .................................................. 0.97

 Chamberlain to Niobrara ................................................ .93

Niobrara to Yankton..................................................... 1.02

Yankton to Sioux City................................................... .90

Sioux City to Blair ...................................................... .87

Blair to Omaha .......................................................... .81

Omaha to Plattsmouth................................................... .71

Plattsmouth to Nebraska City............................................ 1.06

Big Sioux:

Flandreau to Dell Rapids ................................................ 2.26

Dell Rapids to Sioux FaUs ............................................... 3.46

Brandon to Hawarden ................................................... 2.25

Hawarden to Sioux City ................................................. 1.00

v AGE OF THE TERRACES.

If we accept the prevalent view that the outer moraine marks the 

maximum extent of the ice in the second Glacial epoch and that the 

formations outside belong to an earlier epoch, it readily follows that 

what we have grouped under the head of "lower bowldery terraces'' 

belong to the later time. Their fresh contour and their relation to the 

loess and extra morainic drift all harmonize with this view. Looking 

further, the twofold grouping of these terraces would correspond well 

to the outer and second moraines. The lower terraces would as easily 

be referred to the times of the third, fourth, and later moraines. Their 

silty character would result from their remoteness from the glaciers, 

much as is found to be true of the higher terraces below Sioux City, 

when the river had left the vicinity of the ice during its earlier and 

greater extension.

The higher bowlilery terraces, according to the scheme adopted, would 

be referred to a time preceding the loess, probably the first subepoch 

of the earlier epoch.
U. S. GEOLOGICAL SURVEY BULLETIN No. 158, PL. XXIII

MILES FROM MOUTH, ALONG CENTER OF 

76 5i 4- 3 a I HOG 9 8, 7 3, a, I. 90,0 a. 7 e. s.

8OO 9 8 7 6 5 A 3 Z I 7OO 9 87654-3? Z I 600 9 8 71 6 54- 3 S

MILES FROM MOUTH, ALONG AX/S OF TROUGH

M O STLY SHALES AND PLASTIC CLAYS 

WITH SOME CHALKSTONE

 \

N

U^ ^

COLORADO AND MONTANA (BENTQN, NIOB&ARA. AND PIERRE) FORMA Tl O NS

DAKOTA \x FORMATION

UPPER CARBONIFEROUS

DtP \MV V

5 TCTEJB CO., PMOTO^JTMO.. WASHINGTON. O, C.

DIAGRAM OF MAIN FEATURES OF THE TROUGH OF THE MISSOURI
TODD.] TROUGH OF THE MISSOURI. 141

More careful study of the terraces, especially after artificial exposures 

have been multiplied by the settlement of the country, promises to be 

one of the most interesting and instructive fields in Pleistocene geology. 

The above is only a beginning of what may be done.

DIAGRAM OF THE TROUGH OF THE MISSOURI.

We have subjoined a diagram (PI. XXIII) showing graphically the 

slope, width, depth, terraces, etc., of the trough of the Missouri River 

from Pierre to Nebraska City. Its data are derived from the reports of 

the Missouri Eiver Commission, railroad levels, and personal observations. Two things of interest are specially notable: One, the difference in width above Yankton as compared with the portion below that 

point; the other, the close correspondence between the width of the 

trough and the softness of the geological strata corraded. The remarkable width of the trough from Sioux City to Blair is probably largely 

due to the assistance of escaping artesian waters from the Dakota 

formation.

A similar diagram, somewhat abridged, showing similar facts for the 

.Missouri below Nebraska City, may be found in Eeport of Missouri 

Geological Survey, Vol. X, 1896, p. 188.

WESTWARD ELEVATION OF THE REGION.

We have referred several times to a possible recent westward, elevation of the region under consideration. We will now consider facts 

which bear upon its amount, extent, and age. These will be of value, 

even if not found decisive.

Along the line between Mitchell and Chamberlain the slope of the 

surface, where it is unaffected by local erosion, descends toward the 

east about 10 feet to the mile. This we may refer partly to the action 

of the ice sheet; but comparing it with the opposite side of the valley 

there is left a considerable amount to be explained by some other cause 

than the erosion of the ice. Farther south we find the same slope prevailing between Pratt Greek and the James Eiver. We even find that 

the plain between the Big Sioux and the Vermilion east of Parker is 

50 to 75 feet lower than the plain between the West Vermilion and 

Wolf Creek west of that place. The determination of the prevalent 

slope farther south in Dakota is rendered difficult by the occurrence of 

interlobular portions of the moraine. If we refer to the table of elevations along the moraine given in our first chapter we find them harmonizing with the idea of a considerable westward elevation.

Passing now into Nebraska we find, it will be remembered, the surface composed mostly of loess, which in its westward portion presents 

a clearly defined and quite recognizable plateau. Upon this we may 

take a number of elevations which will indicate very satisfactorily the 

general slope of the country. Farther east, with a little care, the original or prevalent level of the loess may be determined Itoin the few
142 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

isolated remnants which appear to be the original surface. The following table presents the results of such determinations along lines 

extending east and west. The figures may be more relied upon in the 

western portion of the field because more closely connected with railroad elevations. In the eastern portion, though largely barometric, it 

is believed that they have need of only slight correction.

Slope in eastern Nebraska.

Locality.

Kimball to Mitchell ..................................

Oakdale to Wisner (Elkhorn Valley) ..................

Humphreys to Blair ..................................

Columbus to Fremont (Platto Valley) .................

Distance.

Miles. 

48

' 30

57

70

40

30

47

36

68

14

33

70

Slope per 

mile.

Feet. 

10

6.6.

5.9

K K

6.3

2.7

5.5

5.9

6.5

1.5

1.6

0

From this we learn: (1) That the James Valley and the Missouri 

below their junction mark approximately the axis west of which the 

western elevation is much more marked, averaging about 6 feet per 

mile. (2) That the slope east of that line is very slight, if anything. 

It amounts to about 1 foot per mile in northern Iowa, and may possibly be found to be less, for our observations are quite limited. Another 

reason for doubt lies in the fact that the elevation of the eastern edge 

of the loess has not been definitely determined, but it can not vary 

greatly from the figures given. (3) That the slope diminishes rapidly 

as it approaches the Missouri in eastern Nebraska, as is indicated by 

the slope between Mapleville and Blair.

A general view of the change of slope indicates that its axis follows 

approximately the boundary between the Cretaceous rocks and the 

older rocks! The Archean quartzites of Dakota seem to have been 

least affected. This axis, which is the eastern limit of the steeper westward acclivity north of our field, continues apparently up the James 

Eiver through Brown County and then curving eastward around the 

head of Coteau des Prairies, extends into the valley of the Eed Eiver.

Date. 1. The relations of the drift to the volcanic ash stratum in 

eastern Nebraska and to the lacustrine beds in Mills County, Iowa, to 

say nothing of less definite beds pointing in the same direction, iudi-
TODD.I WESTWARD ELEVATION. 143

cate that during the Pliocene and on into the Glacial epoch the western 

elevation had not begun to affect materially the slope of the region 

under consideration. Farther west it may have considerably advanced 

before the advent of the ice.

2. The position of the ice sheet during the occupation of the principal moraine indicates little, if any, relative elevation toward the west. 

The westward pushing of the ice south of the Wessington Hills is difficult to explain if the slope of the' land was as great as at present. 

The existence of the glacial lake around the Bijou Hills and above is 

more easily understood if the land was at a lower level than at present. 

Nevertheless, it is not fatal to the hypothesis to suppose the relative 

elevation to have been as great then as now.

3. The deposition of the loess, which we have conceived to be a fluviolacustrine formation, favors also a gentler slope than the present. The 

force of this argument would be somewhat weakened if it could be satisfactorily shown that the deposition of similarly fine material is consistent with considerable velocity in the depositing waters. We might 

then perhaps conceive the western portion of the loess to consist of the 

gigantic "alluvial fans" of the Niobrara, Elkhorn, and Platte, formed 

largely under subaerial conditions. Moreover, with an overloading of 

silt this would bo more conceivable.

4. The deflection of the ice toward the east during the formation of 

the second moraine, together with the change of drainage about White 

Lake and Lake Andes, though perhaps not demanding, strongly favors 

the conclusion that the elevation had at that time become perceptible.

5. It will be noticed that the relation of the high terrace of the Platte 

River to the higher land in the vicinity of Fremont, Nebraska, suggests 

that the desertion of the old channel across Saunders County may have 

been due to its cutting through the divide which formerly separated 

the Platte from the Elkhorn, and that this was subsequent to the formation of the terrace. If the terrace was, as we have supposed, contemporaneous with the outer moraine, and the cutting through at Fremont 

was the result of an increased slope of the river, it follows that the 

elevation was still in progress after the occupation of that moraine, and 

may have continued indefinitely.

C. Another feature of the terraces points to the same general conclusion. Along the Missouri Eiver between Monona County, Iowa, and the 

southern line of the State, there are no high terraces of importance on 

the east side of its present valley. There are a few points where the 

terraces along its eastern tributaries appear, but they do not project 

beyond the trend of the present bluffs. Along its western side, on the 

contrary, as we have already noticed, there are extensive terraces 60 

to 100. feet high, found between Tekamah and Calhoun, between Florence and Omaha, and between Bellevue and the mouth of the Papillion, so also near the mouth of the Weeping Water. If no tilting had 

occurred, the converse should be true, for the rule that the streams in
144 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

the northern hemisphere erode more rapidly the right side of their 

valleys has few exceptions.

Whether the upward movement continues to the present is uncertain. 

The slight slope of the Missouri from Chamberlain to Sioux City would 

seem to favor the idea that such is not the case, and yet the corrasion 

of the stream may possibly keep pace with the slow elevation which 

may still continue. That river is so laden with sand that the deepening of its real bed may be so masked as to be undiscoverable. Considerable light upon this subject in general may be derived from the general sections. Pis. XXIY and XXV.

NORTHWARD ELEVATION OF THE REGION.

In our tables of elevation marking the general level of the loess 

there appeared a marked slope to the south. This is brought out very 

distinctly in the list of elevations, which is arranged for the most part 

along north-south lines. While this feature is most clearly indicated 

in Nebraska, it appears also in less degree in western. Iowa, also in 

the valley of the Big Sioux above Sioux Falls, and in the southern 

portion of the region within the principal moraine. The following 

table will illustrate and impress these points:

Slope in icestern loiva.

Locality. Distance. Slope per 

mile.

Plain view to Humphreys, Nebraska ...................

Osceola to Fairmount, Nebraska ......................

Plain view to Faiij j^ount, Nebraska....................

Southwest of Coleridge to Northside, Nebraska .......

David City to Dorchester, Nebraska....................

Coleridge to Dorchester, Nebraska ....................

Blair to Louisville, Nebraska .........................

Louisville to Turlington, Nebraska ...................

Blair to Turlington, Nebraska. ........................

Sibley to Marcus, Iowa ...............................

Marcus to Hillsdale, Iowa.............................

Sioux City to California Junction (Missouri Valley)... 

Missouri Valley to East Nebraska City................

Wentworth to Taopi, South Dakota...................

Taopi to Hartford, South Dakota......................

Wentworth to Hartford, South Dakota................

Airlie, Minnesota, to Larchwood, Iowa ................

Lenox to Vermilion, South Dakota....... ............

Plankinton to Grandview, South Dakota ..............

Miles. 

54 

42

125 

25 

42

127 

35 

21 

56 

40

125 

70 

62 

13 

13 

26 

38 

37 

23

Feet. 

2.5

.8 

1.3

.4 

1.2 

2.6 

3.5 

1.2 

2.6 

1.3

1.3

1.4

1.5 

3 

5 

4

4,4

3.5

 1.3
U. S. GEOLOGICAL SURVEY BULLETIN No. 158, PL. XXIV

Wessington Hills

Imer-lobular moraine

Moraine 

Boxelder Cr 1., ~~ ~~ - _ Moraine ,. _ 

 - - East Vermilion /?.

West Vermilion ffT ~ ~ L Moraine Medison Wentworth CoJeman 

ffecfstone Cr. l/ilas Howard i ~S$$&K^ _ d * / 

/

State fine

\ Pipestone

1/708

WMii& Wessington Springs Second

*^* ' Moraine Forestburg

 "- " ~ ^v**T T

r_ j I I r ,'l 'I "I ,V .'i'i ' I'i "I i'1-VJ I ,1 ,i ' J"' ' ' < 'I'M- rT^-i 'i i ,

SECTION FROM THE 'BIG BEND TO PIPESTONE, MINN.

Medicine Butte

Mount Vernon M itch el I

Moraine I James Rwer Pi'erre Cr.

~~ ~~ ~ - - _ __East Vermilion River

~~~-±. Moraine <;/., /, r/-

WestVermilionRiver Moraine > ~Jjfcx&&±,~^__ oKt/n«i,r. BigSiouxRiver Garretson 

Soencer \ Sa/e/n ^-^.Montrose//fs'^f-V-S-'^^^s^^y^f^A'^i!^ vd&sr^Stt- > ««s>^ -^> . / .^^

<**» ' 

The Mound

 SURFACE Of ICE AT THE OCCUPATION Of THE OUTER MORAINE. 

ALLUVIAL

SECTION FROM MEDICINE BUTTE TO THE MOUND NORTH OF LUVERNE, MINN.

yyj'A LOESS ','0!JV.|

TILL

c^V:| TERTIARY

COLORADO CLAY AND CHALK

MM DAKOTA El

WS(

TXyti| SIOUX

Choteau Creek Hills

Outer Moraine Interlobularmoraine^, - ~- - . ^ 

. Missouri River / ^"~~^^ y ^, ~"

laaP^ftC £msn^ICr' S^Cr.

10 IS 20

James Ridge Turkey Ridge 

Inter lob u far moraine

Beaver Cr. James River Orange Grand View Paulina

e \

*.rCr. James River \TurkeyCr. -

/ ,/---- * / '-" +* "" I /-./_H>_ a / --" l/er/n///,

~. _ Moraine Big Sioux River

4 Brule Cr. | Hawarden

L

SECTION ON THE FORTY-NINTH PARALLEL

SCALE or MILES

SECTIONS ACROSS THE GLACIATED REGION EAST AND WEST
TODD.] NORTHWARD ELEVATION. 145

The localities in the above table stand for the upland in their vicinity. 

Further information is afforded by the general sections, PI. XXV.

From a study of this table we come to the following general conclusions: The region outside of the principal moraine has uniformly a 

general slope toward the south. In the loess region this averages on 

the long slopes from 1.3 to 2.6 feet per mile. In the Coteau des Prairies 

region it is from 4 to 5 feet per mile. Between the outer and the second 

moraines there exists on the east a slope of 3.5 feet to the mile, but 

west of the James there is a rise southward of from 1 to 1.5 feet per mile 

from the line of the Chicago, Milwaukee and St. Paul Eailway. This 

irregularity may be connected with a slight increase of elevation of the 

loess summits from the vicinity of the Missouri south to the southern 

borders of Knox and Cedar counties, and be made to argue for the 

recent anticline, with its axis running east and west, near the Niobrara. 

Gen. G. K. Warren arrived at a similar conclusion from independent 

data noted farther west. 1 This hypothesis may help to relieve two 

other difficulties of some weight the absence of the loess along the 

Missouri north of the Niobrara at levels below its summit in Kuox 

County, Nebraska, and the difference in elevation of the lower bowldery 

terrace at Running Water and Vermilion, Dakota.

An examination of the James Eiver Valley brings out the remarkable fact that within the second moraine the general level of the valley 

is exactly horizontal in a north-south direction. From the vicinity 

of Mitchell to Columbia and beyond, for more than 140 miles, the variation in altitude according to railroad elevations (notice especially those 

of the Chicago, Milwaukee and St. Paul Eailway) is scarcely 10 feet. 

Letcher, Diana, Cavour, Eedfield, Ashton, Aberdeen, Groton, and 

Columbia are all above the plain which we have named for convenience 

Lake Dakota.

Date. From the steep slope of the drift plain of the Coteau des 

Prairies of the upper Big Sioux, we infer the existence of a northern 

elevation before the loess epoch. Quite probably, however, that greater 

slope is to be referred to a considerable elevation since that time. 

Being between the Dakota and Minnesota lobes, it would be naturally 

depressed more than lower latitudes, and when the ice was removed 

its resilience would be correspondingly energetic.

The generally distinct and continuous slope of the region to the 

south, wherever the loess has been deposited, is no more than a fluviolacustrine theory of the loess would explain without perceptible crustal 

movement. This northward slope for the most part was quite regular. 

We have noted the most apparent exception, concerning which we 

need add no more at present.

From the perfect horizontality of the general surface within the second moraine, which, although of lacustrine origin, seems to be continuous with the surrounding till, we conclude that the elevation must

1 Preliminary Report of Explorations In Nebraska and Dakota, 1855-57, pp. 23, 24.

Bull. 158 10
146 MORAINES OP SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

have ceased for southern Dakota by the time the ice had receded to 

the third moraine; and we have found no evidence that this elevation 

has continued in any other portion of our field.

AGE OF THE TROUGH OF THE MISSOURI.

In regions north of the field covered by this paper evidence is especially strong that the courses of such streams as the Cheyenne and 

Grand rivers were formerly eastward to the valley now occupied by the 

James .River. This is derived mainly from the movements of the ice 

sheet, the traces of old divides, and the narrow character of the trough 

of the Missouri through this region. For fuller treatment of this topic, 

see a paper by the writer in the Proceedings of the American Association for the Advancement of Science for 1884.

There is evidence, also, in the region under consideration which indicates that the channel of the Missouri above Niobrara is of recent 

origin. The White Eiver has a channel rivaling or even surpassing 

the Missouri in breadth if we consider its broad ancient valley 300 feet 

above the present one. There is no valley through the Bijou flange of 

buttes which corresponds to it in size. The Bijou Eange itself seems 

to be an old watershed or remnant of Tertiary rocks which extends 

between the basins of the White and Niobrara rivers. What the 

ancient course of the White Eiver was there is not yet evidence of 

much importance to show, but, remembering the higher level at which 

it formerly flowed, it may be suggested that a portion of its course 

remains in the Eed Lake channel. Nor is it very difficult to imagine 

that it once ran along the upper course of American Creek past White 

Lake.

It now remains to consider the age of the Missouri below that point, 

more particularly that portion bordering the State of Nebraska. Two 

questions present themselves: 1. Was it pre-Glacial, so far as its location, or was it post-Glacial in origin? 2. If post-Glacial, did it reach its 

deepest excavation before the loess epoch or in more recent times'? If 

we should find reason for believing it of pre-Glacial origin, the exact 

date of its location and excavation are not particularly connected with 

our subject.

IS THE TROUGH OF THE MISSOURI OF PRE-GLACIAL ORIGIN?

We proceed to take up the first of these questions. In favor of the 

pre-Glacial origin of the trough the following points may be urged:

1. Striae, supposed to be of Glacial origin, have been found down to 

the level of the water at Omaha, and very nearly down to that level in 

southwestern Mills County, Iowa. Not unlikely more careful examination would disclose such striae at other points.

2. The bed rock lies at a depth of from 50 to 110 feet, or even 125 feet 

at Omaha, below the present low-water mark; and this leads us to pre-
U. S. GEOLOGICAL SURVEY BULLETIN No. 158, .PL. XXV

Beresford

Outer Moraine

LittleSioux River 

Cherokee /

- a*, SI/CGStCf \ lidWa ' FOG ft

x^fK^sg^tss?, Asrf^S^jv. \ / ^S^f^ 

\

____r_^- __ _ , . Hurley Vermilion River

^P^^t^^^^f^g^^ggB^^

SECTION FROM ALEXANDRIA, S.D., TO CHEROKEE, JOWA.

Spencer Bridgewater Freeman

Norfolk

\ Elkhorn

\ xs^ /^^i^^^^^^^^^J^^ Cr~ SECTION FROM SPENCER, S.D., THROUGH TUPHEY R/DGE TO NORFOLK, NEB.

n ALLUVIAL LOESS AND 5AAIDS

isoo Ar.

Firesteel Creek 

James River / Moraine

Mitchell / Enemy Cr.

Choteau Cr.

Grand View

M

MIOCENE

COLOfAOO CLAYS 

DAKOTA FOftMAT/Of 

SIOUX QUAftTZITE

IO ts

SCALE Of MI

SECT/ON FROM MITCHELL, S.D., SOUTH-WEST ACROSS T/iE M/SSOUR/.

SECTIONS RADIATING ACROSS THE MORAINES
TODD.] AGE OF TROUGH OF MISSOURI. 147

sent in more careful detail the results of examination at live different 

points, viz: Sioux City, Blair, Omaha, Plattsmouth, and Nebraska 

City. In the first three cases sections have been kindly furnished the 

Survey by the engineers of the railroads which cross at these several 

points, A few notes from engineer Parkhurst, of the Plattsmouth 

bridge, were received soon after its building. The Nebraska City section has been constructed from notes, taken by the writer in 1880, of an 

examination carried on by the Corps of United States Engineers, who, 

to throw light on the history and working of the Missouri, ran a line of 

borings nearly across the valley at that place. The main facts at these 

different points may be stated as follows (for a Ml expression of them 

we refer to the subjoined cross sections in Pis. XXVI and XXVII):

At Sioux City the river hugs the casters bank. The rock, judging 

from that exposed in the bank, is wholly of Dakota sandstone and 

shales. The river at this point is about 900 feet in breadth and from 5 

to 15 feet in depth. The rock lies under; jath the present channel of the 

river on an average from 35 to 80 feet. It lies approximately parallel 

to the bottom of the water, but near the western bank slopes downward 

toward the west, and its depth beyond that point has not been determined. These remarks apply particularly to the section near Prospect 

Hill. The new one, upon which the Pacific Short Line is built, does 

not differ materially from it. Along the line of the lower bridge, that 

of the Sioux City and Pacific Railroad, quite different conditions were 

found. The three deeper borings in the vicinity of the channel, though 

extending 120 feet below the low-water mark, are reported not to have 

struck any bed rock. The section is illustrated in PI. XXVI. When 

we learn that the Dakota formation is composed mainly of sand, with 

thin layers of clay, it seems not improbable that its strata may have 

been mistaken for the loose deposit of the river. In favor of that fact 

attention is called to the representation of white clay, blue clay, and 

sand upon the east bank, which would correspond in character with 

strata of the Dakota. Moreover, upon the west -bank, at a depth of 

70 feet, is a stratum of clay with its upper surface concave, as though 

worn by a stream, which also suggests a stratum of the Dakota. Taking the borings as given in the report of the Missouri River Commission for 1890, however, it would appear that river deposits extend to a 

depth of 120 feet, and how much more has not been determined.

At Blair the river occupies a more central portion of a valley 11 to 

12 miles in width. It is three-quarters of a mile east of the high terrace at Blair. The bed rock in the vicinity of the present channel, 

where the bridge of the Sioux City and Pacific Eailroad crosses it, is 

from 47 to 50 feet below low-water mark. Its surface is quite level in 

an east-west direction, but seems to dip, or at least to end, abruptly 

to the north, for a boring 1 mile north of the bridge did not reach rock 

at a depth of 140 feet. Borings for a mile longitudinally near the 

bridge, however, indicate a slight decline of surface toward the south.
148 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

At the railroad bridge at Omaha the river lies close to the western 

bank, and, as has been stated before, the rock near by rises above the 

level of the stream. Underneath the present channel, which at this 

point is ordinarily about 1,000 feet in width and 2 to 15 feet in deptb, 

bed rock lies from 30 to 75 feet below low-water mark. These remarks 

apply to a section of the Union Pacific Eailroad bridge. The section 

given in our illustration (PI. XXVII) is that determined by a set of 

borings crossing the river about half a mile north of the Omaha and 

Council Bluffs wagon bridge. In this there appears a shelf in the rock 

bottom on the Omaha side about 20 feet below the surface, or 15 feet 

below low water. A little east of the river and for three-quarters of a 

mile farther in that direction the rock lies at a depth of about 80 feet, 

and three borings east of that failed to strike bed rock, though pene- 

.trated to a depth of 90 feet. Moreover, the character of the deposits 

seems to be that of the river, or possibly, in one case, bowlder clay. It 

is labeled clay and gravel.

At Plattsmouth a much less complete section has been obtained, but 

the river is close to the western side of the valley and the rock lies 

from 32 to 54 feet below low-water mark. Moreover, more recent borings have developed the fact that the bottom is quite uneven, and that 

in some places bed rock lies considerably lower. About a mile and a 

half farther north borings were carried to a depth of over 85 feet 

without striking rock.

At Nebraska City the river also lies next the western side of a valley 8 miles in width. The river is about 1.000 feet in breadth, and in 

places 30 to 40 feet in depth. By the borings before referred to, which 

were carried on under the directions of Mr. L. E. Cooley, assistant 

United States engineer, for more than 4 miles, at distances of from 

2,500 to 3,000 feet apart, the rock was found to lie at a depth of from 

60 to 102 feet below low-water mark. The deepest point found was at 

the easternmost boring where, according to his statement, " bowlder 

clay" was struck, suggesting the idea that it may have been the western 

side of an old channel partially filled with bowlder clay. The average 

depth of the rock, which on the whole is quite even, may be placed at 

about 75 feet below low-water mark.

From the Report of the Missouri Eiver Commission for 1890 we learn 

that north of the bridge about 2 miles borings were carried to a depth 

of about 170 feet at several points before striking bed rock, and the 

inference drawn by the engineer was that he had discovered a preGlacial channel. He reports that the " principal bed below the general 

level of the north and south valley of the Missouri is a very tenacious, 

hard, drab-colored clay, mixed with angular fragments of stone, generally of lime." though he reports one of red quartzite, but it is not 

from this deep channel. He does not doubt that it is till. Assuming 

that this deep hole is connected with the easternmost boring shown 

in our figure, he makes the channel run S. 80° E., and suggests that it
U. S. GEOLOGICAL SURVEY BULLETIN NO. 158 PL. XXVI

Chamberlain Section 

C.M.&StP.Ry.bridge Sioux City Section 

S.C.&P.Ry. bridge

Sioux City Section 

the second bridp'e

The Blair Bridge Section

Surface I004£L^_^-

9 .

Horizontal Scale

VerticaL Sca.le

SECTIONS ACROSS MISSOURI RIVER AT CHAMBERLAIN, SIOUX CITY, AND BLAIR.
TODD.] AGE OF TROUGH OF MISSOURI. 149

may be a portion of an old valley of the Platte.. It is difficult to harmonize it with the present Missouri. On the whole, it seems more 

rational to suppose that the deposit in question is a Carboniferous 

stratum, and that he has been misled by the interruption or removal 

of a thin layer of limestone which has, near by, formed the bottom. 

However, the case should be remembered and further light be sought 

on the subject.

Now, it appears improbable that the present stream should be still 

excavating the rock bounding its trough; its depth is too great, it would 

seem. And yet, at what time since the Glacial epoch is it likely to 

have reached the bed rock under its channel? On generally received 

principles we should be inclined, from the depth of the rock, to argue 

for the pre-Glacial excavation of the trough. Whether this is strongly 

sustained we shall see presently.

3. The occurrence of till quite low down. At Florence it is found 50 

feet thick and more, extending below low-water mark. North of Council 

Bluffs, near Plattsmouth, and in Mills County, Iowa, typical till is 

found down to within 30 feet of the level of the river.

In favor of the post-Glacial origin of the immediate valley of the 

Missouri, it may be argued as follows:

1. A comparison of the course of the Missouri with that of the Mississippi on opposite sides of the State of Iowa brings out the contrast that, 

while the latter presents rapids of considerable height, nothing of the^ 

kind is found along the Missouri. As these rapids have been distinctly 

traced to changes in the course of the Mississippi during the Glacial 

epoch, or the want of correspondence of its present channel with that of 

pre-Glacial times, the absence of rapids in the Missouri would argue in 

favor of no such divergence, and since we should as easily expect a 

similar divergence in one case as in the other, if both had pre-Glacial 

channels, we have some reason for believing that the Missouri had no 

pre-Glacial channel.

2. Deposits which are evidently of lacustrine and of pre-Glacial origin 

are found in such close proximity to the present valley as to argue 

against the idea of a river occupying the trough previous to the deposit 

of the till. We refer particularly to the section north of Pacific Junction, 

which has been described on a previous- page. This, however, is not 

conclusive, for we may conceive of small lakes attending a river.

3. Wherever the deposits have been examined in the present trough 

of the Missouri they have displayed only sand and clay, with no trace 

of till except in one solitary case, which has been mentioned in the 

Nebraska City section PI. XXVII. At Blair and Omaha a few scattered bowlders are found next the rock, but they have evidently been 

rolled along by the action of the water. At Nebraska City and Omaha 

clay balls, evidently formed by the caving of clay banks and the rolling 

of the fragments by the current, occur frequently down to the rock. If 

the trough were of pre-Glacial age it should be found filled more or less
150 MORAINES OP SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

with, bowlder clay. Even if it has been more deeply excavated since the 

ice age, till should be found occupying a considerable part of the trough.

4. The bed rock, wherever it has been exposed, as at Blair and at 

Omaha, has shown a uniformly waterworn appearance, with no traces 

of planation or stride. Though bowlders have been found upon the 

surface of the rock to the depth of a foot or so, there is no evidence of 

their corrading the rock as if moved by ice.

We may sum up the evidence from the sections with this result: The 

depth of bed rock differs much in the different sections, even where 

the localities seem quite uniform. It will be remembered that a boring 

1 mile north of Blair bridge is said to have gone 140 feet without striking bed rock. When we consider the greatly different kinds of material which the river has excavated it seems likely that the deepness of 

the channels is the result of softness of the material rather than of 

great age or the position of an ancient base level. It seems probable that 

there would be variations in the depth of the trough of the river similar to those in its width, and the causes for each are probably similar. 

Hence we conclude that the preponderance of evidence is in favor of a 

recent excavation of the lower, portions of the channel. At the same 

time it should be remembered that we have no complete sections across 

the trough and that there is a possibility that an older and deeper 

channel of pre-Glacial age may yet be found.

THE TROUGH OF THE MISSOURI STILL DEEPENING.

In support of the view, which may strike some as novel, that the 

river may cut down to the bed rock at the present time during freshets, 

we have the united testimony of two or three experienced observers. 

Mr. L. E. Cooley, in his report on the improvement of the Missouri 

Eiver at Nebraska City during the year 1879,1 makes the following 

statement:

The ordinary limit of scour is not the limit when the hank is held, provided the 

ordinary scour does not extend to permanent strata. The causes which induce 

heavy cutting will induce heavy scour, provided that cutting is stopped, which will 

extend to permanent strata if the causes continue sufficiently long. * . * *

In many of the horiugs which have been made here, indurated clay halls, with 

vegetable matter, covered with a coating of sand, along with a motley collection of 

gravel stones, are found within a short distance of permanent strata. A precisely 

similar collection containing gumbo balls.in a soft state was dredged from 60 feet 

depth at the works. These balls are from cutting banks, and the proof is conclusive that since the river has been running in silt banks, as at present, scour has 

occasionally, at least, reached permanent strata at 70 to 90 feet depth.

Mr. E. Gerber, assistant engineer of the Fremont, Elkhorn and Missouri Valley Eailroad, who has had direct oversight of the Blair bridge, 

states without qualification that the river at that point cuts down to 

bed rock twice a year, and he further expresses the opinion that "At 

many places, especially in sharp bends, where no artificial contraction 

of the channel takes place, and where there is no greater width than

1 Report of U. S. Engineers for 1879-80, Part II, pp. 1066, 1071.
U. S. GEOLOGICAL SURVEY BULLETIN NO. 158 PL. XXVII

Nebraska City Section 

______Brown clay ona soil

lue cloy

Horizontal Scale _p miles

SECTIONS ACROSS MISSOURI RIVER AT OMAHA; PLATTSMOUTH, AND NEBRASKA CITY.
TODD.] AGE OF TROUGH OP MISSOURI. 151

at our bridge, the river scours the bed rock at high water if the rock 

is not too low." A demonstration of this fact is shown in fig. 31 from 

soundings taken at the Blair bridge in 1883.

Mr. George A. Lederle, local engineer of the Omaha bridge, expresses 

a similar opinion, though no definite observations have been made at 

that point to establish it.

If it be urged that the excavation of so great a valley as is found 

above Blair and near Nebraska City since the Glacial period is inconceivable, it may be replied that much may be explained by the nature 

of the formations through which the river has corraded its course.

Fio. 31. Record of soundinga at Blair bridge, 1883.

Above Blair the Carboniferous limestone does not appear, and doubtless dips far below the bottom of the river. The great width of the 

valley above that point has been excavated, therefore, in the loose 

deposits of the Cretaceous and Tertiary, while its deepening was prevented by the limestone ledge near Blair and De Soto. Even the Carboniferous deposits, though at points largely abounding in limestone, 

are perhaps one-half clay and very friable sandstone and shale. Moreover, the limestone ledges are rarely more than 10 feet in thickness, 

and the thickest easily (separate into blocks less than 3 feet in diameter. Cliffs of alternating rock and clay may be quite as easily 

degraded as those of clay alone.

The inequalities of the depth of the bed rock seem to correspond 

with the character of the strata. For instance, at Blair the shallowness of the trough seems to be referable to a thick stratum which 

appears above the river at Omaha; the shallowness at Plattsmouth, to
MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

a thick limestone stratum which appears a little above the river at 

.Rock Bluff. The rock thus far dips gently toward the north. The 

greater depth at Oinaha may be due to the series of clay layers which 

intervene between the two, together with the effect of the plunging of 

the current over the limestone stratum as it was worn from the south 

toward the north. The great depth at Nebraska City may be similarly 

referred to the rapidity of the stream after passing the limestone 

stratum at Rock Bluff. Quite possibly, also, this has been increased 

by a fold which crosses the river at Jones Point, near the mouth of the 

Weeping Water. The strata dip considerably to the south, perhaps 

100 feet in the distance of a mile. This brings the series of clays 

which are exposed in the vicinity of Nebraska City down into the river 

and accounts for the deeper excavation at that point.

The modus operandi of the excavation of the trough seems to be in 

this wise: While the stream has rapid velocity it preserves much of its 

straight, narrow, deep channel, which characterizes its upper portion, but 

when such a channel has attained a uniform slope it begins to form 

bends which begin the widening of its valley. During this stage the 

deepest places are in the sharp bends, and only at such points has 

the river rock bottom. If it is heavily burdened with sand and silt, as 

in the case of the Missouri, between such bends, according to the 

testimony of engineers as well as the common experience of river 

captains, the river is very shallow, as the current here is slackened 

and sand accumulates, especially during high water.

As the river meanders back and forth and the bends contiually work 

down stream, the whole breadth of the valley becomes scoured out to 

the depth of the sharpest bends. In this way we may reconcile its present partially filled condition with its recent excavation. The work of 

broadening the trough does not begin at all points at the same time. 

Where the strata are soft and friable the stream reaches its base-level 

of erosion, and expends its energy in widening its valley, while at 

points where harder strata occur it is spending all its energy in cutting 

out its bottom.1 Thus we may explain, in part at least, the remarkable 

widening of the trough of the Missouri between Yankton and Blair, 

and in less degree between Council Bluffs and Eock Bluff, and again 

between Jones Point and Peru.

We conclude, therefore, that though the trough may possibly have 

been located before the Ice age, its deeper portions must have been 

excavated after the deposition of the surrounding till. Moreover, this 

excavation may have begun soon after the lowan or even the Kansau 

stage of the Glacial period.2

If it should be asked how we reconcile the arguments in favor of its 

pre-Glacial origin with the conclusion at which we have arrived, we 

should simply ascribe the strise preferably to the action of river ice, 

though they may have been caused by land ice of an older epoch, and

'Cf. Powell's Exploration of the Colorado River, p. 202 et seq. 

2 Of. Todd, New lights on the drifts: Proc. Iowa Acad. Sci., 1898.
TODD.] AGE OF TROUGH OF MISSOURI. 153

the deposition of till at altitudes near the river where it is not the 

result of landslides to depressions in the surface on which the till was 

deposited, for the general surface of the Carboniferous strata seems to 

have been far from even. The deep deposits of sand and gravel in the 

vicinity of Council Bluffs and Omaha we should ascribe to similar cause. 

It would seem that when the Missouri began its course during or after 

the drift period, and in crossing some of these deep holes large quantities of this material collected in them.

The very rough surface of the Carboniferous rocks is graphically 

described by Dr. F. V. Hayden in his Final Eeport on Nebraska, p. 25. 

Speaking of eastern Nebraska, he says: "If we can imagine the superficial material entirely removed from the country, the surface, as it 

seems to me, would be rugged in the extreme. * * - * The massive 

piles of limestone would stand around here and there scattered over the 

surface like gigantic ruins." This quotation, while expressing a truth, 

may be misunderstood. If we should remove the pre-Glacial clays and 

sand beds the buttes of Carboniferous limestone would probably rise 

less than 200 feet above the intervening valleys.

If this conclusion be correct, there may not have been very great erosion of the older rocks since the Ice age.

WAS THE TROUGH EXCAVATED PREVIOUS TO THE LOESS EPOCH?

This depends largely upon the theory one may hold concerning the 

origin of the loess. If it is looked upon as eolian, the two may have 

been developing simultaneously. In that case the conception would be 

that the Missouri began its course after the Kansan epoch, and that the 

material of the loess must have been derived from its bars and banks 

during its lower stages and spread over the uneven surface adjacent. 

But if we look upon it as of a lacustrine or a fluvio-lacustrine origin, 

it would seem necessary to conceive the trough of the Missouri to 

have been subsequent. If we favor the latter views, the base-level 

of erosion and deposition must have been approximately coincident 

with the present upland level of the loess region. We may have some 

fragments of the original surface still extant in the " flats" which we 

have already mentioned as occurring in western Iowa, Nebraska, and 

Missouri. Accordingly, the most of the upland loess was deposited no 

later than the lowan epoch. If it seems incredible that this trough, 

which really is of vast extent, has been excavated since that time, we 

may find it more credible by considering the following points:

1. The present trough may have been largely excavated from Pleistocene deposits. We have already alluded to the very uneven surface 

of the older rocks. If the drift were resting upon deep sand beds, as 

has been found in northern Nebraska, this would assist largely in the 

removal of the material.

2. The Missouri during the Wisconsin epoch was the main channel for 

carrying off the water from the whole western edge of the great ice 

sheet. Estimates will be found more fully given in the Report of the
154 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

Missouri Geological Survey, Vol. X, p. 202. According to these, the 

probable average size of the stream was about ten times 'greater than 

at present. This would add greatly to its eroding power.

3. The loess has a peculiar property for creeping and rearranging 

itself at lower levels. This subject will be found more fully treated in 

the Proceedings of the Iowa Academy of Sciences for 1897. We simply 

call attention here to the following facts: The loess upon steep slopes 

frequently shows a step-like surface. Most generally it attracts little 

attention, and has been referred by some to the checking by vegetation along steep hillsides or to the tramping of grazing animals. Even 

in this moderate degree deep excavations will show that these steps are 

caused by a series of slight faults running transverse to the direction 

of the slopes. They may be compared to crevasses of glaciers. It 

appears that this phenomenon occurs when moisture has accumulated 

in the base of the formation and dissolved the cementing material of 

the loess and rendered it plastic, or the moisture may be in the 

underlying clay or sand, rendering it similarly plastic. Occasionally 

this phenomenon becomes so marked that the crevasses or faults have 

a throw of several inches. During rain or the spring thaws these 

cracks are filled and recernented. Similar results are also accomplished 

by hillside wash, which frequently becomes very marked upon steep 

slopes. After prolonged rains the formation becomes saturated and is 

very easily washed away and rearranged. Because of its straticulate 

structure and homogeneous color and composition it is very difficult for 

anyone to distinguish the newly arranged material from the original 

deposits. In this way we may find a rational explanation of the recent 

origin of the troughs of the Missouri and its tributary streams, and 

also in considerable degree of the uneven surface and great vertical 

range of both the loess and the drift.

ELEVATIONS.

Elevation above sea level of stations on Fremont, Elknorn and Missouri Valley Eailroad

west of Norfolk Junction.

[Furnished by the kindness of E. Gerber, assistant engineer.]

Main line: Feet.

Battle Creek................. 1,606

Burnett.................. .... 1,695

Oakdale ..................... 1,726

Neligh....................... 1,761

Clearwater................... 1,808

Ewing....................... 1,875

Inman ....................... 1,946

O'Neill....................... 1,992

Emmet............... r ....... 2,039

Atkiuson..................... 2,125

Stuart .................. ..... 2,171

Newport ..................... 2,249

Bassett ...................... 2,340

Long Pine ................... 2, 416

Mainline Continued: Feet.- 

Ainsworth ..................." 2,538

, Johnstown ................... 2, 618

Wood Lake.................. 2,704

Arabia....................... 2,735

Thatcher...... .. T ... ..1...... 2,669

Valentine............!....... 2,598

Creighton Branch:

Norfolk (town)».............. 1,542

Hadar ....................... 1,574

Pierce ....................... 1,599

Morehouse ................... 1,657

Plainview...... .............. 1,700

Creightou.................... 1,617

1 .This is 1 mile from tlio junction, which is 1,532 feet.
TODD.J ELEVATIONS. 155

Elevations on the Chicago, St. Paul, Minneapolis and Omaha Railway. 

[Furnished by the kindness of C. "W. Johnson, chief engineer.]

Locality. Distance. Altitude.

Main line:

Sioux City, crossing of Second and Ho ward streets 

Missouri Eiver ..............................

Covington ..................................

Dakota City.................................

Coburn Junction ............................

Do.......................................

Hubbard....................................

Grade over Pigeon Creek ....................

Bottom of Pigeon Creek.....................

Simons Siding (summit) .....................

Grade of Elk Creek .........................

Bottom of Elk Creek ........................

DO....................................:.

Summit .....................................

Emerson Junction ...........................

Flourney.....................................

Fender......................................

Bancroft ......................................

Lyons ...........*........... .................

Oakland ....................................

Craig ....---.......---:.....................

Summit ................ ....1. ...............

Tekamah.....................................

Herman......................................

Hiland.......................................

Blair.........................................

Mills..................:......................

Calhoun......................................

Summit......................................

Florence ...................... .............

Omaha........................:..............

Ponca Branch:

Coburn Junction .............................

Jackson......................................

Grade at Elk Creek ..........................

Bottom of Elk Creek.........................

Grade at Elk Creek ..........................

Bottom of Elk Creek.........................

Summit ...................................:..

Grade at Badger Creek .......................

Bottom of Badger Creek......................

Pouca...^....................................

Miles.

0

5

10

12

14

20.5

20.5

22

23.5

23.5

23.6

26.2

27.2

34.5

39

48.7

56.3

65

70

71.5

79

86.2

91.2

96.2

101.5

105.2

116

120

126.2

0

3

4.2

4.2

6

6

11

11.5

11.5

16

Feet. 

1,122.2 

1,102.33 

1,124 

1,121

1.124

1.125

1,161

1,356

1,307

1,436

1,356

1,336

1,352

1,494

1,450

1,399

1,347

1,316

1,306

1,300.3

1,280

1,341

1,075

1,050

1,031

1,100

1,026

1,094

1,232

1,033

1,065

1,124

1,141

1,156

1,140

1,174

1,152

1,279

1,243

1,225

1,162
156 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158. 

Elevations on the Chicago, St. Paul, Minneapolis and Omaha Eailway Continued.

Locality.

Norfolk Branch:

Summit ........................................

Wakefield.... ..................................

Hoskins ........................................

Norfolk ........................................

Hartington Branch : 

Wakefield......................................

O 

Sioux Falls Branch : 

Junction ........................................

Little Rock River 

Bridge .....................................

Kanaranza Creek 

Water......................................

Bridge ......................................

Beaver Creek v

Water......................................

Distance.

Miles. 

0

2.5

9.5

18.6

19.2

19.2

31.3

34.2

' 38

46.5

0

3.7

3.7

10

17.5

17.5

24

33.8

181.8

184.5

187.4

187.4

190.1

196.9

198

198

199.5

203.7

206.2

907 1

210.3

211.1

216.1

219.3

219.8

224.4

225.2

Altitude.

Feet. 

1,450

1 RA-t

1,404

1,469

1,470

1,452

1,643

1,809

1 fiXd

1,542

1 404.

1,422

1 404.

1 4^

1 PiOQ

1 490

1,672

1 4.04. ^

1,633

1,691

1 fi99

i KAq

1,665

1, 538

1 499

1 ^11

1,569

1,516

1,469

1 K1K

1,423

1,451

1,543

1,443

1,385

1,383

1,392
TODD.] ELEVATIONS. 157 

Elevations on the Chicago, St. Paul, Minneapolis and Omaha Railway Continued.

Locality.

Siotix Falls Branch Continued. 

Ilow and high water. ...........

Terrace south of river ..........................

Big Sioux River, high and low water ...........

Skunk CreekWater, sec. 31, T. 102, R. 50.. .................

Hartford Siding, sec. 22, T. 102, R. 51 .............

Summit, grade, sec. 9, T. 102, R. 52 ................

East Vermilion River 

Water, sec. 27, T. 103, R. 53 ...... ..........'..

West branch of East Vermilion 

Water, southwest corner of sec. 15, T. 103, 

R. 53. ................................:...

Salem, sec. 13, T. 103, R.55.... ............. ......

West Vermilion River, water, sec. 15, T. 103,

R. 55. ......................... ;...... ......

 Wolf Creek, water, sec. 20, T. 104, R. 56 ..........

Fawn Lake, water, T. 105, R. 58 .................

Stony Creek, water, sec. 25, T. 106, R. 60 ..........

James River, water, sec. 12, T. 106, R. 61'. . .......

Distance.

Miles. 

232.4

232.4

234. 4

240.2

240.4

241.6

243.4

250

250

254.4

261.2

268

268

268.3

269.5

269.5

275.9

279.5

281

290. 6

303.5

313

320.2

325

Altitude.

Feet. 

( 1,281'

I 1,302 

1, 307

1, 363

1, 394

f 1,381

I 1, 385 

1 4.71

1,403

1,449

1,465

1,561

1,692

1, 455

1,469

1,471

1 4fi8

1,480

1,586

1,517

1,457

1,370

1,320

1,253

1,212

1,276
158 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

Elevations along the Dakota Central Division of the Chicago and Northivestern Railway 

from Haivarden, Iowa, to Iroquois, South Dakota.

Locality. Station. Altitude.

Hawarden............................................

Crossing, Chicago, Milwaukee and St. Paul 

Grade ...........................................

Ground...........................................

East bank Big Sioux..................................

Do...............................................

Do..............................................

Alcester i.............................................

Do ...................... .^........................

Do ...............................................

East bank Brule Creek ...............................

DO.................'..........:...................

Do ...............................................

Beresford ............................................

Do................................................

Do...............................................

Centreville............ I..............................

East bank Vermilion .................................

Do...............................................

Do...............................................

Do...............................................

Hurley...............................................

Do. ..............................................

Crossing of Chicago, Milwaukee and St. Paul .........

Grade of Chicago, Milwaukee and St. Paul............

Grade of Chicago and Northwestern ...................

Parker ...............................................

East bank of West Vermilion.........................

Do ..............................................

Do...........................~..................

Do...............................................

Canistoga ............................................

Salem and crossing of St. Paul, Minneapolis and Omaha 

East bank of West Vermilion .........................

Do...............................................

Canova...............................................

Vilas.................................................

East bank of Rock Creek..

Do...-....--.....-....

Carthage..................

East bank Redstone Creek. 

Esmond ...................

Do....................

Do...--... ..........

Iroquois...................

0

18

18

38

108

378

468

521

538

584

748

908

928

1,118

1,358

1,463

1,487

1,528

1,538

1,953

2,154

2,568

2,579

2,579

2,579

2,627

2,637

2,837

3,027

3,337

3,487

4,017

4,182

4,277

4,662

5,187

5,510

5,657

5,857

5,865

6,227

6,397

6,617

6,672

Feet.

1,182 

1,179 

1,182 

1,181 

1,437 

1,355 

1,320 

1,344 

1,310 

1,345 

1,513 

1,505 

1,340 

1,240 

1,233 

1,223 

1,207 

1,240 

1,325 

1,272 

1,360 

1,335 

1,330 

1,335 

1,340 

1,340 

1,506 

1,500 

1,560 

1,555 

1,515 

1,485 

1,530 

1,525 

1,480 

1,426 

1,466 

1,440 

1,436 

1,430 

1,450 

1,425 

1,4CO
TODD.] ELEVATIONS. 159 

Elevations along a preliminary survey from Chamberlain, South Dakota, to Lemars, Iowa.

[Furnished by B. B. Colborne, who made it in the interests of the Chicago, Milwaukee and St. Paul 

Railway. Datum, 300 feet below starting point, which happened to be the bottom (not bottom land) 

of the Big Sioux River.]

Locality. Station.

Elevation 

above 

datum.

One mile north of Chamberlain, South Dakota, water 

in Missouri River above sea 1,321 feet...............

Chamberlain, station.................................

One mile east of Chamberlain.........................

Summit, sec. 34, T. 104, R. 70 .........................

East end of Red Lake.................................

Water in lake ........................................

Bijou Hills Gap ......................................

Pratt Creek, water, sec. 2, T. 99, R. 68 ................

Do...............................................

Sec. 33, T. 99, R. 68...................................

Summit ..............................................

Pease Creek, sec. 32, T. 98, R. 66......................

Summit ..............................................

West end of Lake Andes .............................

Lake Andes, water ...................................

Channel southwest from lake .........................

Between moraine and lake............................

Choteau Creek:

Bottom, sec. 29, T. 96, R. 63.........................

Sec. 25, T. 94, R. 62, grade..........................

Sec. 36, T. 94, R. 62, grade ..........................

Sec. 36, T. 94, R. 62, water ..........................

Summit ..............................................

Emanuel Creek:

Quarter of a mile above Springfield station .......

Three-quarters of a mile below Springfield station.

Near station ......................................

Water in Missouri River at 

Springfield .......................................

Yankton .........................................

Yankton, grade of Chicago, Milwaukee and St. Paul....

Edge of river bottom at mouth of Turkey Creek, sec. 

13, T. 94, R. 54; station from Springfield..............

Summit ..............................................

West edge of Vermilion, second bottom ...............

0

400

500

500

1,300

2,850

0

300

500

859

1,150

1,400

1,400

1,450

1,500

2,000

3,000

3,050 '

0

300

600

2,200

2,500

2,750

Feet.

221. 95

251

300

505.7

450

440

649.8

358.4

358.4

492

522.9

395

463

330

319.6

326

342

280

184

181

169

327

123

104

98

76

48

64

58

227

110
160 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

Elevations along a preliminary survey from Chamberlain, South Dakota, to Lemars,

Iowa Continued.

Locality.

Vermilion River : 

Grade, sec. 23, T. 94, R. 52 (Bloomingdale) ........

Second bottom, west edge ..........................

Second bottom, east edge .........................

Brule Creek : 

Sec. 16, T. 94, R. 50 (Emmett). ....................

Water ............................................

Big Sioux :

Railroad crossing at Akron ............................

Broken Kettle Creek, sec. 8, T. 92, R. 47 ...............

Summit, sec. 36, T. 92, R. 47 ...........................

Sec. 23, T. 92, R. 46...... .............................

West Floyd River :

Water............................................

Floyd River :

Lemars, 5-10 feet lower than Illinois Central station . .

Station.

2,950

3,500

3,150

3,500

3,550

3,700

3,850

4,050

4, 100 '

4,500

4,650

4,850

5,100

5,100

5,150

5,200

5,300

5,400

Elevation, 

above, 

datum.

Feet. 

32

38

102

148

105

95

125

268

27

0

28

277

158

( 280

\ 301 

105

87

8.6

79

60

84

60

95

Elevations on survey north of Lake Andes, from sec. 28, T. 96, R. 63, to Platte Creek 

Crossing, sec. 3, T. 99, R. 68.

Locality.

Crossing of Lake Andes, sec. 16, T. 97 R. 64, (water 7

Platte Creek ..........................................

Station.

0

500

800

1,150

1,450

Elevation.

Feet. 

319.6

564.9

487

548

358
ELEVATIONS. 161

Elevations along the Chicago, Milwaukee and St^Paul Railway in Dakota and part of Iowa, 

as per profiles in chief engineer's office.

[Furnished by the courtesy of D. J. Whittemore, chief engineer.]

Locality.

Elevation 

above Lake 

Michigan.

Elevation 

above 

the sea.

Sheldon, Iowa ........................................

Boyden,Iowa .....................i..................

Patterson, Iowa ......................................

Summit west of Patterson ............................

Rock Valley..........................................

Junction of Rock Valley..............................

Rock River:

Track........................................ ....

Water............................................

Inwood ..............................................

Sioux .River:

Track ............................................

Water..........................;.................

Canton...............................................

Crossing at Canton Junction...........................

Worthing ..................!.........................

Lennox ...............................................

Vermilion River (bridge).............................

Chitago and Northwestern Railway, crossing east of 

Parker.............................................

Parker ...............................................

Suinmi t west of Parker................. t .............

Junction at Marion Junction..........................

Station at Marion Junction...........................

Wolf Creek bridge....................................

Bridgewater .........................................

Emery Station ...................... j................

Pierre Creek bridge ..................................

Alexandria...........................................

James River bridge east of Mitchell:

Track............................................

Water............................................

Station at Mitchell...................................

Junction west of Mitchell............................

Mount Vernon........................................

Plankinton...........................................

White Lake..........................................

Kimball..............................................

Pukwana ...................... 1.....................

Feet. 

822 

830 

842 

869 

662 

658

657

635

880

657 

635 

655 

670 

772 

763 

711 

*

736 

758 

894 

856 

858 

830 

829 

797 

720 

761

629

615

710

706

822

937

1,055

1,197

955

Feet.

1,404

1,412

1,424

1,451

1,244

1,240

1,239

1,217

1,460

1,239

1,217

1,247

1,252

1,354

1,345

1,293

1,318

1,340

1,476

1,438

1,440

1,412

1,411

1,379

1,302

1,343

1,197

1,292

1,288

1,404

1,519

1,637

1,779

1,537

Bull. 158 11
162 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

Elevations along the Chicago, Milwaukee and St, Paul Railway in Dakota and part of Iowa, 

as per profiles in chief engineer's office Continued.

Locality.

Running Water Branch :

Bridge over James River 

TYa nliWater .......................................

Tyndall..... .....................................

Sioux City and Dakota Division :

Utica ..............................................

Bridge over James River 

Track........................................

Water........................................

Gayville........ .......... ........................

Heckling .........................................

Bridge, Vermilion River 

Track........................................

Burbank .........................................

Elk Point ........................................

Jefferson .........................................

McCook ...........................................

Bridge, Sioux River 

Track ........................................

Low water ...................................

Elevation 

above Lake 

Michigan.

Feet. 

772

739

856

920

733

602

598

587

756

827

643

629

772

793

797

602

586

570

576

565

559

538

559

551

540

527

521

521

v 4-Q7

RIO

Elevation 

above 

the sea.

Feet. 

1,354

1,321

1,438

1,502

1,315

1,184

1, 180'

1,169

1,338

1,409

1,225

1,211

1,221

1,354

1,375

1,379

1,184

1,168

1,152

1,158

1 147

1,141

1,110

1 141

1,133

1,122

1,109

1,103

1,103

1 07Q

1 OQ^i
TODD.] ELEVATIONS. 163

Elevations along the Chicago, Milwaukee and St. Paul Railway in Dalcota and part of Iowa, 

as per profiles in chief engineer's office Continued.

Locality.

Elevation 

above Lake 

Michigan.

Elevation

above

the sea.

Elk Point to Sioux Falls Junction: Feet. Feet.

ElkPoiut ........................................ 540 1,122

Bridge, Sioux River 

Track........................................ 521 1,103

Water........................................ 507 1,089

' Westfield......................................... 540 1,122

Akron (Portlandville) ............................ 564 1,14G

Chicago and Northwestern crossing (Hawarden) .. 587 1,169

Calliope.....-........-....-......----.--.--..-.-- 591 1,173

Bridge, Sioux RiverTrack........................................ 598 1,180

Water.........................-----.---....-. 571 1,153

Eden....!......................'.................. 631 1,213

Austen.............--.--..-..-....-...--.-------. 613 1,195

Fair-view.....-........--.....-........-.-...-.--. 623 1,205

Beloit........................................... 649 1,221

Bridge, Sioux River 

Track........................................ 648 1,230

Water........................................ 633 1,215

Crossing at Canton Junction..................... 670 1,252

Bridge, Sioux River at Sioux Falls 

Track........................................ 804 1,486

Water........................................ 787 1,369

Sioux Falls....................................... 802 1,384

Bridge over Sioux River at Dell Rapids 

Track........................................ 907 1,480

Water........................................ 879 1,451

Station, Dell Rapids.............................. 901 1,483

Bridge, Sioux River 

Track......................................... 909 1,491

Water........................................ 894 1,476

Track........................................ 928 1,510

Water........................................ 911 1,493

Sioux Falls Junction............................. 929 1,511

Southern Minnesota Division:

Airlie, Minnesota................................. 1,070 1,652

Flandreau........................................ 983 1,565

Bridge, Sioux River 

Track........ ................................ 938 1,520

AVater........................................ 928 1,510
164 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

Elevations along the Chicago, Milwaukee and St. Paul Railway in Dakota and part of Iowa, 

as per profiles in chief engineer's office Continued.

Locality.

Southern Minnesota Division Continued.

Coleman, Dakota. ................................

Bridge, East Vermilion River 

Track ........................................

Bridge, James River 

Track........................................

Hastings and Dakota Division :

Bridge, Minnesota River 

Track............ ............................

Water........................................

Station, Milbank Junction ........................

Bridge, James River 

Water........................................

Bath....:........................ .............. .

Elevation 

above Lake 

Michigan.

Feet. 

943

929

1,109

1,108

1, 081 .

1,067

1,040

1,122

980

888

814

727

652

627

644

 720

402

383

370

fftQ

1,415

1,225

1,258

1,190

891

719

696

684

715

714

715

847

945

Elevation 

above 

the sea.

Feet. 

1,525

1,511

1,691

1,690

1,663

1,649

1,622

1,704

1,562

1,470

1,396

1,309

1,234

1, 209

1,226

1,302

984

965

952

1 141

1,997

' 1, 807

1,830

1,772

1,473

1,301

1,278

1 2fifi

1,297

1,296

1,297

1,429

1,527
TODD.] ELEVATIONS. 165

Elevations along tlie Chicago, Milwaulcee and St. Paul Raihvay in Dakota and part of Iowa, 

as per profiles in chief engineer's office Continued.

Locality .

Whetstone Branch :

Wilmot ..........................................

James Valley line : 

Mitchell. .........................................

Woousocket . . . . ..................................

Virgil.......................... ..................'

Chicago and Northwestern crossing (Wolsey). ....

Bonilla....... ....................................

Redfield. .........................................

Mellette ..........................................

Warner ..........................................

Aberdeen .........................................

Westport. ........................................

Frederick ........................................

Ellendale ........................................

Elevation 

above Lake 

Michigan.

Feet. 

559

584

606

637

706

713

720

731

755

765

764

750

729

705

706

708

792

793

712

715

745

783

864

Elevation 

above 

the sea.

Feet. 

1,141

1,166

1,188

1,219

1,288

1,295

1,302

1,213

1,337

V347

1,346

1,332

1,311

1,287

1,288

1,290

1,294

1,295

1,294

1,297

1,227

1,365

1,446

NOTE. In preparing the above statement the elevations above Lake Michigan were determined 

by reducing the datum lines of the various profiles on file in the office to lake level, beginning at 

Milwaukee, thence to La Crosse, and thence by four different routes to a common point in Dakota, 

 where it was found that the extreme variation was not more than 5 feet. The elevations given are 

about an average of the extremes found. E. 0. Reeder, assistant engineer.
166 MORAINES OF SOUTHEASTERN SOUTH DAKOTA. [BULL. 158.

Supplementary list.

Locality.

Scotland and Armour line :

Tripp ............................................

Tripp and Mitchell line. ..............................

Tripp ............................................

Mitchell.................................... .....

Elevation 

above Lake 

Michigan.

Feet. 

756

974

8QQ

932

974

811

756

712

Elevation 

above 

the sea.

Feet. 

1,338

1/556

1,481

1, 514

1,556

1,393

1,338

1,294

Elevations along ike Sioux City, O'Neill and Western Eailway. 

[Obtained through the kindness of J. H. Charles, of Sioux City, from P. C. Hills, receiver.]

Locality.

Siding, sec. 25, T. 29, R. 6. E.... ........................

Alien.................................................

Summit east of Dixon ................................

"Rvn HQ\W i c\r

Orchard ..............................................

O'Neill.... ....... ....................................

Elevation 

above 

datum.

Feet. 

106. 69

100

110

175

280

515

480

550

445

465

540

600

660

825

640 

668

846

860

920

965

947

965

Elevation 

above sea.

Feet. 

1, 111. 8

1,106

1, 116

1,181

1,286

1 521

1, 486

1,556

1, 451

1,471

1,546

1,606

1,666

1,831

1,661

1,640

1,674

1,852

1,866

1,926

1,971

1,953

1,971
ELEVATIONS. 167 

Elevations along the Sioux City, O'Neill and Western Railway Continued.

Locality.

Elevation 

above 

datum.

Elevation 

above sea.

Feet. Feet. 

Western line of Hall County.......................... .......... 2,338

Western line of Eock County......................... .......... 2,576

Western line of Brown County........................ .......... 2,763

Crossing, Middleloup, Cherry County, water level..... .......... 2,932

Highest point, R. 33, Cherry County, three-fourths mile

east of west line.................................... .......... 3,379

Highest point, R. 37, Cherry County, one-half mile east

of west line ........................................ .......... 3,658

Western margin of Cherry County .................... .......... 3,837

Highest point, R. 44, Sheridan County, west line................. 3,945

Crossing, Box Butte Creek, Sheridan County, western 

margin ....................................................... 3,845

Elevation of the Sioux City and Northern Railroad. 

[Through the kindness of S. J. Seals, receiver.]

Locality. Elevation 

above sea.

Sioux City, shops east of Division street 

Dalton, Iowa............................

Struble, Iowa ...........................

Garretson, South Dakota ................

Feet. 

1, 109.6 

1,212.5 

1,271.7 

1,496.1

INDEX.

Ancient Island, exposure near............ 131

Area discussed, limits of.......... ........ 14

Augbey, S., cited on fossils ................ 98

Bailey,'S. W., aid by....................... 119

Bain, H. J\, cited on petrified bones ....... 16

Battle Creek, description of valley of.... 104-106

Beals, S. J., elevations furnished by....... 167

Bennott, strife near......................... 69

Benton formation, location of exposures of. 15 

Berks, Nebraska, figure showing exposure

near..................'.............. 68

section near............................ 80

Big Sioux Gap, course of outer moraine

near................................ 34-35

Big Sioux Elver, cause of the great bend

of................................ 108-109

course of moraine from Vermilion Point

to .................................. 35-36

description of valley of................ 107

elevations on..................... 108,157,158

exposures along........................ 82-84

low-water slopes of .^.................. 140

terraces along........................ 138-139

view of................................. 138

Bijou Hills, figure showing portion of

moraine near....................... 24

view of................................. 43

Bluir, depth to bed rock at................. 347

plate showing section across Missouri

Biver at............................ 148

Blair bridge, record of soundings at........ 151

Bonhomme, course of outer moraine from

SpiritMound to.................... 29-32

Boonsboro, Iowa, section from the Missouri

Biverto............................ 101

Bowlders, distribution of................... 39-41

Brandon Township, exposure in............ 106

Bridgewater, figure showing gouge from

qnartzite exposure near............ 126

photograph of strife on quartzite near.. 126 

Brule Creek, course of outer moraine from

Canton to...... .'..... .............. 32-34

Call, B. E., shells determined by ........... 121

Canton, Iowa, course of outer moraine from

Brule Creek to ..................... 32-34

section near............................ 86

Carroll County, Iowa, section near south

line of.............................. 101

Castalia, wells near........................ 120

Cedar Creek Hills, description of .......... 25-26

figure showing......................... 25

Page. 

Chamberlain, elevations between Lemars,

Iowa, and........................ 159-160

plate showing section across Missouri

Biver at............................ 148

terrace at........................ 128,130,131

Chamberlin, T. C., reference to............. 22

work of................................ 13

Channels, ancient, description of ........... 60-61

Charles, J. H., acknowledgments to........ 17

elevations furnished by .............. 166-167

Chicago and Northwestern Bailway, elevations along......................... 158

Chicago, Milwaukee and St. Paul Bailway,

elevations along.................. 161-165

Chicago, St. Paul, Minneapolis and Omaha

Eailway, elevations along........ 155-157

Choteau Creek Hills, description of........ 28

Cleveland, D. C., information furnished by . 73 

Colborne, B. B., acknowledgments to ....... 17

elevations furnished by.............. 159-160

Coleridge, plate showing base of drift near. 74 

Concord, Nebraska, drift near............. 73

Cooley, L. E., quoted on the deepening of

the Missouri Biver................. 150

Coteau des Prairies region, boundaries of.. 103 

character of surface of............... 103-104

bowldery knolls in................... 109-110

hummocks in .......................... 110

strife in.............................. 110-111

valleys of............................ 104-107

Council Bluffs, Iowa, sections near..:..... 88-89

Creighton, Nebraska, drift near............ 73

Croninger, C. J., information furnished by.. 125 

Crow Lake, map of osar-like ridges near... 23 

Dakota sandstone, location of exposures of. 15 

Dana, J. D., cited on moraine near Turtle

Eidge.............................. 22

Dell Bapids, description of .............. 107-108

Drift, eastern boundary of................. 58

relation of underlying formations to ... C7 

western boundary of................... 56-58

East Bijou, distribution of drift in......... 44-45

East Vermilion Eiver, elevations on........ 157

Egan, section near ^........................ 138

Elevations, lists of......................... 39,

48-49, 58-59, 91-92,108, 154-167 

method of obtaining.................... 16

Elk Creek, elevations on................... 355

Elkhora Biver, terrace along............... 63

Emanuel Creek Gap, description of........ 28-29

Enemy Creek, ancient channel near........ 119

169
170 INDEX.

Page. 

Enemy Creek Hills, view of................ 115

Fairview, section near ..................... 83

view of Big Sioux River near.......... 138

Firesteel Creek, ancient channel near...... 119

Florence Nebraska, view of bluff above ... 72

sections near........................... 78,79

Fossils in loess, occurrence of.............. 98

Fort Eandall, moraine near ................ 54

view of lower bowldery terrace near.. -. 132 

Fremont, Nebraska, exposure near......... 135

section west of.......................... 79

Fremont County, Iowa, thickness of loess in 100 

Fremont, Elkhorn and Missouri 'Valley

Eailroad, elevations along.......... 154

Garretson, driftless area near .............. 84-85

Gerber, E., acknowledgments to............ 16

elevations furnished by................ 154

quoted on the deepening of the Missouri ............................. 150-151

Grand view, ancient swamp near ........... 121

view of the moraine from 2 miles south of 27

wells near.............. 1 ................ ]20

Gravel and sand deposits, character of..... 66-67

Greenwood, terrace at...................... 132

view of lower bowldery terrace near... 134 

Hartiiigton, Nebraska, drift near........... 73

Hawarden, Iowa, elevations between Iroquois, South Dakota, and........... 158

Hayden, F. V., cited on Carboniferous rocks 153

cited on exposures of Benton formation. 15

work of................................ 13

Helix alternata, occurrence of.............. 98

Herman, Nebraska, terrace near............ 133

Herrick,Nebraska,plate showingloess near. 102

section of south bluff of Missouri Biver

near................................ 72

terrace [near............................ 132

Hills, F. C., elevations furnished by...... 166-167

Hopkins, H. M., information furnished by.. 125 

Hnghitt, Marvin, acknowledgments to ..... 17

Ice sheet, plates showing extent of....... 120,122

Iowa, drift in .............................. 85-91

slope in western........................ 144

Iroquois, South Dakota, elevations between

Hawarden, Iowa, and............... 158

James Eidge, description of valley of...... 122

elevations on......................... 162,164

exposures of older rocks in valley of ... 122

views of................................ 28,30

Johnson, C. W., acknowledgments to ....... 16

elevations furnished by .............. 155-157

Keg Creek, Iowa, figure showing section

between Silver Creek and.......... 94

section near............................ 90

Lake Andes outlet, view of ................ 26

Lake Dakota, cause of...................... 125

Lederle, G. A., acknowledgments to ........ 17

 cited on deepening of the Missouri.... 151

Lemars, Iowa, elevations between Chamberlain, South Dakota, and .......... 159-160

Lesterville, morainic hills near............. 29

Letcher, well section at .................... 125

Loess region, boundaries of ................ 56-58

elevations in ........................... 59

Logan Creek, elevations on................. 156

Lower Brule Agency, terrace at............ 129

Page. 

Maple Creek, Nebra ska, section on......... 78

McCook, figure showing section near ...... 86

Meek, F. B., cited on fossils ................ 98

Middle Eaccoon Eiver, section near junction of Willow Creek and.......... 102

Milford,Nebraska, section near............ 80-81

Missouri Eiver, age of trough of......... 146-154

character of valley of.................. 62

diagram of the trough of............... 140

low-water slopes of..................... 140

plates showing sections across ....... 148,150

pre-Glacial course of................... 30

silt terraces at the Great Bend......... 128

table of heights of terrace along....... 137

terraces along........................ 128-138

view of Great Bend.................... 128

Missouri Valley, Iowa, section near ........ 88

Mitchell, Alexander, acknowledgments to.. 17 

Montrose, plates showing osars, etc., near.. 36, 38 

Moraine, definition of term ................ 37

outer, structure and position........... 37-38

Mount Vernon, wells near.................. 120

Nebraska, distribution of drift in.......... 69-81

slope in eastern ........................ 142

thickness of loess in northern.......... 100

Nebraska City, depth to rock at............ 148

plate showing section across Missouri

Eiver at............................ 150

Nicollet, J. N., work of..................... 13

Niobrara, Nebraska, drift near ............. 69

exposure near.......................... 134

Niobrara formation, location of exposures

of ............................v..... , 15

Niobrara Eiver, pre-Glacial course of....... 30

Omaha, depth to bed rock at............... 147

plate showing section across Missouri

Eiver at......'...................... 150

Osmond, Nebraska, figures showing cuts

east of ............................. 75,76

Pacific Junction, Iowa, figure showing exposure near.....:.................. 68

sections near........................... 89,90

striae near.............................. 69

Pierre formation, location of exposures of.. 15 

Plainview, wells near...................... 120

Plankinton, spotted surface near .......... 121

Platte Eiver, terrace along................. 63

Plattsmouth, depth to rock at ............. 148

plate showing section across Missouri

Eiver at............................ 150-

Pleasant Hill, Nebraska, section near...... 80

Ponca, Nebraska, section at............... 74

Ponca Eeach drift region, description of... 53-55 

Pony Hills, South Dakota, view of........ 114

Powell, J. "W., cited on river cutting ....... 152

Pratt Creek, course of moraine east of..... 18

course of outer moraine from Eunning

Water to........................... 25-27

course of outer moraine from Turtle

Point to............................ 19-25

terrace in valley of..................... 131

Pukwana, ancient channel near............ 46

Eed clay, character of...................... 66

Eed Lake drift region, boundary and area

embraced in........................ 42-43

character of drift in.................... 43
INDEX. 171

Page. 

Red Lake drift region, data from wells and

exposures in ....................... 50-51

elevations in .........- ........-.-.... 48-49

hypotheses concerning................. 51-53

Eeeder, E. 0., explanation by.............. 165

Region discussed, limits of................. 14

Eiverside Station, Iowa, section near ...... 88

Rockport, moraine near..................... 115

Running Water, course of outer moraine

from Pratt Creek to.............:.. 25-27

Sand hills, description of................... 64

Santee Agency, Nebraska, sections near... 71 

view of iipper bowldery terrace near .. 130 

volcanic ash stratum near ............. 70

Shimek, B., cited on fossils ................ 98

Silver Creek, figure showing section between Keg Creek and.............. 94

Sioux City, Iowa, depth to bed rock at..... 147

elevation at............................ 155

plate showing section across Missouri 

River at............................ 148

sections near........................... 87

terrace near............................ 133

Sioux City and Northern Railway, elevationsalong...-.........-....:...... 167

Sioux City, O'Neill and Western Railway,

elevations along ................. 166-167

Sioux Falls, exposures near................ 84

sections at and near............... 84,102,103

strife near.............................. 68

Sioux quartzite, figure showing markings

on.................................. Ill

Sioux River, elevations on ............... 162-163

Skunk Creek, description of valley of..... 106

knolls near............................. 109

South Dakota, drift in ..................... 81-85

Spirit Mound, course of outer moraine from

Bonhomme to...................... 29-32

view of................................. 30

Split Rock Creek, description of valley of.. 106

knolls near........................... 109-110

Striae in loess region ....................... 68-69

Striae in second moraine.................... 126

Succinea obliqua, occurrence of............ 98

Terraces in loess region, description of .... 63-64

Till, character of........................... 65-66

Todd, J. E., cited on excavation of the

trough of the Missouri............. 152

cited on fossils......................... 98

Turkey Ridge, description of.............. 31-32

map of................................. 32

Turtle Point, course of moraine near ...... 18

course of outer moraine from Pratt

Creek to ........................... 19-25

Page. 

Turtle Point, description of ................ 19

view of................................. 19

Turtle Ridge, map of southwest Wessingtons and............................ 20

transverse section of................... 21

view of................................. 20

view of old overflow channel in........ 22

description of.......................... 19-23

Union County, plate showing details of

moraine in......................... 34

Upham, Warren, cited on exposure at Palisade ............................... 106

work of................................ 13

Valley Springs, strife near ................. 69

Vermilion, sections at and near........... 74,134

terraces at and near................... 81,133

Vermilion Gap, description of morainenear. 32 

Vermilion Point, course of moraine from

Big Sioux River to................. 35-36

Vermilion River, elevations on........... 158,160

Vermilion Valley, description of........... 123

Wall Lake, view of inner slope of moraine

south of....... ... ............ 35

Walnut Creek, Iowa, figure showing cut

near................................ 94

Warren, G. K., cited on elevation .......... 145

cited on Tertiary rocks ................ 16

reference to............................ 26

work of................................ 13

Wells, data from........................... 51

Wessingtons, southwest, description of.... 22-24

map of Turtle Ridge and............... 20

section of.............................. 37

West Bijou Hills, old water line on ........ 47

West Point, Nebraska, sections near....... 77, 78

view of ash stratum near............... 70

volcanic ash stratum near.............. 70

West Vermilion River, elevations on....... 158

Wheeler, terraces at arid near........ 129,132,136

White, C. A., cited on boundary of loess.... 97

formation named by.................... 15

White Lake, wells near .................... 120

White River, description of valley of...... 133

drift south of .......................... 45-46

view of buttes south of................. 43

Whittemore, D. J., acknowledgments to.... 16

elevations furnished by.............. 161-165

Winchell, N. H., cited on Algonkian formations ............................... 15

cited on boundary of loess.............. 97

reference to ............................ 93

Yankton, terrace near ..................... 132