1

R. I. 4520 MAY 1949

i

UNITED STATES

DEPARTMENT OF THE INTERIOR

J. A. KRUG. SECRETARY

BUREAU OF MINES

JAMES BOYD, DIRECTOR

REPORT OF INVESTIGATIONS

INVESTIGATION OF COAL DEPOSITS IN SOUTH CENTRAL ALASKA

AND THE KENAI PENINSULA

*

BY

ALBERT L. TOENGES AND THEODORE R. JOLLEY
R. I. 4520,

May 1949.

REPORT OF INVESTIGATIONS

UNITED STATES DEPARTMENT OF THE INTERIOR - BUREAU OF MINES

INVESTIGATION OF COAL DEPOSITS IN SOUTH CENTRAL ALASKA

AND TEE KENAI PENINSULAL/

By Albert L. Toenges2/ and Theodore R. Jolleyl/

CONTENTS

Page

Introduction ........................................................... 2

Acknowledgments ...................... . ............... 4

Areas investigated during the reconnaissance ...... ................ 5

Matanuska Valley coal field ..................................... 5

Evan Jones mine, Jonesville, Alaska ......................... 7

Eska Creek area .................. .................. ...... 10

Wishbone Hill, southwest of Jonesville ....................... 11

Healy River District, Nenana coal field .......................... 12

Suntrana mine, Suntrana, Alaska .............................. 12

Usibelli strip mine .......................................... 14

Diamond strip mine, Healy, Alaska ............................ 15

Lignite Creek area ... .................................... 15

Jarvis Creek area ......................................... ..... 15

Mt. McKinley Park area .......................................... 18

Mt. McKinley bituminous coal mine, Yanert, Alaska (also known as

Yanert mine) .................................................. 18

Riley Creek ................................................. 20

Moose Creek and Boundary Creek .............................. 20

Tertiary coal-bearing formation (Nenana) ..................... 20

North boundary of Mt. McKinley Park ......................... 22

Savage River ........................................... 22

* Sanctuary River ... ................................. 24

Teklanika River ......................................... 25

Sushana River .................. ....................... 26

Mt. McKinley Park Highway .................................... 28

Mile Post 39 ................... ..... ... ......... 28

Mile Post 42 .................................... . 29

Polychrome Pass ....................................... 30

Kenai Peninsula in vicinity of Homer .............................. 31

Homer Coal Corp. mine ...................................... 36

l/ Work completed on manuscript February 4, 1949. The Bureau of Mines will

welcome reprinting of this paper, provided the following footnote

acknowledgment is used: "Reprinted from Bureau of Mines Report of Investigations 4520."

/ Principal coal mining engineer, Fuels and Explosives Division, Bureau of

Mines, Pittsburgh, Pa.

/ Mining engineer, Coal Branch, Fuels and Explosives Division, Bureau of

Mines, Pittsburgh, Pa.

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R. I. 4520

ILLUSTRATIONS

Follows

Fig -page

1. Areas described in report ............... ......... ........... 4

2. General development map Evan Jones Coal Co. mine, Jonesville,

Alaska .............. ........ .... .. ...... ............. ...... ........ 8 v

3. Surface plant, Evan Jones mine ... .................... 10

4. Suntrana mine, Suntrana, Alaska ................................ 10

5. Usibelli strip mine, Healy Creek, Alaska ...................... 14

6. Hydraulicking Usibelli mine, Healy Creek, Alaska ............. 14

7. Area adjacent to north boundary McKinley National Park ....... 18

8. Sketch map Homer-Kenai Peninsula, Alaska .................. ...... 32

INTRODUCTION

The development of Alaska depends on the existence of an adequate fuel

supply in the Territory. The need to investigate coal deposits was recognized as early as 1911, when the first investigations were conducted in

Alaska by engineers of the Bureau of Mines.

Conditions existing in the Bering River and Matanuska coal fields, as

found by Dr. Robert A. Holmes, former Director of the Bureau of Mines, are

described by the Honorable W. L. Fisher, former Secretary of the Interior./

Following Dr. Holmes' investigation, a party of Bureau of Mines engineers headed by R. Y. Williams visited the Bering River field in 1912 in

cooperation with the Navy Department. A detailed examination was made of

the Bering River field, and 855 tons of coal were mined from three prospects

on Trout Creek. This bulk sample was delivered to the Navy for steaming and

other tests. A description of the work of the field party and results of

tests of the coal by the Navy Department and the Bureau of Mines has been

published.5/

During 1920 to 1922, the comparative steaming properties of Alaska bituminous coal, lignite, and wood were determined by the Bureau of Mines.6

4 Fisher, Walter L., Alaska Coal Problems: Bureau of Mines Bull. 36, 1912,

32 pp.

/ Report on Coal in Alaska for use in United States Navy: House of Representatives, 63d Cong., 2d Sess., Doc. No. 876, Washington, 1914.

/ U. S. Bureau of Mines, Steaming Value of Alaska Lignite: Rept. of Investigations 2090, 1920, 2 pp.

Davis, John A., and Hopkins, Paul, Comparative Steaming Tests of Alaska

Lignite and Spruce Wood: Bureau of Mines Rept. of Investigations

2103-B, 1920, 16 pp.

Davis, John A., and Hopkins, Paul, Comparative Steaming Tests of Nenana

Lignite and Matanuska Bituminous Coals: Bureau of Mines Rept. of Investigations 2412, 1922, 9 pp.

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R. I. 4520

In the early 1920's, the Bureau of Mines established a coal laboratory

at Anchorage, where Alaska coals were analyzed. Subsequently, this laboratory was transferred to the Alaska Railroad and was used by the railroad for

coal and other tests.

Since 1910, the Bureau of Mines has made analyses of coal from Alaska,

and the results of these analyses have been published.1/ The coal analyzed

was obtained from mines, tipples, delivered lots, and face samples of coal

deposits, and these samples were obtained in the field by engineers of the

Bureau of Mines and geologists of the U. S. Geological Survey.

Because of the shortage of petroleum and petroleum products in Alaska

during the war, low-temperature carbonization assays of coals from the Broad

Pass, Forty-Mile, Matanuska, and Nenana fields were made by the Bureau of

Mines, and the results were published.8/

Coal beds in the Matanuska field contain interbedded impurities in the

form of shale, clay, and bone. The coal should be cleaned mechanically to

obtain a satisfactory fuel. A coal-preparation study of bituminous coal from

the Eska and Evan Jones mines was made by engineers of the Bureau of Mines,

and the results were published.2/

Coal production in Alaska is less than the requirements, and coal is imported to make up the deficiency. The cost of this imported coal is high.

Greater production is necessary to supply coal for Army installations, industry, and homes. At present, there is only one bituminous coal mine (Evan

Jones) in Alaska. The output of this mine is used at Fort Richardson, Anchorage, and by the Alaska Railroad. The economic life of this mine is limited

(reported to be 3 years), and its closing, because of accidents or exhaustion,

will cause great hardship to the inhabitants of Alaska. There is need to develop new, modern mines for the production of bituminous coal in the Matanuska

field.

The expanding tourist and recreational facilities in the McKinley National

Park will result in increasing the demand for coal, and investigation of the

deposits in this area is advisable to determine the feasibility of developing

mines to supply this demand.

The opening of land for settlement along the Alaska Highway in Alaska and

the Richardson Highway will necessitate the development of coal reserves near

these highways for a fuel supply for settlers.

A detailed investigation of coal reserves on the Kenai Peninsula is desirable to determine the reserves of coal for a source of fuel for homesteaders

near Homer and for the industrial development now being considered in this area.

7/ U. S. Bureau of Mines, Analyses of Alaska Coals: Tech. Paper 682, 1946,

114 pp.

/ Selvig, W. A., Ode, W. H., and Davis, Joseph D., Low-Temperature Carbonization of Alaska Coals: Bureau of Mines Tech. Paper 668, 1944, 16 pp.

%/ Geer, M. R., and Yancey, H. F., Washability Characteristics and Washing of

Coals from the Matanuska Field of Alaska: Bureau of Mines Rept. of Investigations 3840, 1946, 17 pp.

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R. I. 4520

During the summer and fall of 1946, a reconnaissance was made of these

areas with the objective of formulating plans for detailed investigations of

minable coal reserves. Modern mines that can be operated efficiently require

large investments, and minable reserves must be known to determine whether

expenditures for mine development and plant are justified. This report describes the results of this reconnaissance and makes recommendation for detailed investigations in the Wishbone Hill area, in the Matanuska field, and

in the area adjacent to Homer on the Kenai Peninsula.

ACKNOWLEDGMENTS

The cooperation of the following are acknowledged:

Kenai Peninsula:

Basil Sinclair, president, Homer Coal Corp.

Evan Jones, general superintendent, Homer Coal Corp.

C. B. Abbott, engineer, Homer Coal Corp.

Bert Hanson, taxi driver and guide.

Holly Sterling, chief engineer, Alaska Road Commission.

Mile Post 341:

Col. J. P. Johnson, general manager, Alaska Railroad.

J. C. Cunningham, assistant general manager, Alaska Railroad.

Ted Munson, section foreman, Alaska Railroad, Lagoon.

Pat Cook, bridge and building engineer, Alaska Railroad.

McKinley Park:

Harold M. Peterson, manager, McKinley Park Hotel.

Grant Pearson, National Park Service, superintendent, McKinley Park.

Elmer Hossler, superintendent, McKinley Park Div., Alaska Road

Commission.

North of McKinley Park:

Clyde Wahrhaftig, geologist, U. S. Geological Survey.

Jarvis Creek:

Charles Hickox, geologist, U. S. Geological Survey.

Diamond strip mine:

Gus Parris, leaseholder.

Jim Dodson and Larry Reed, lessors.

Healy River:

Capt. A. E. Lathrop, president, Healy Creek Coal Corp.

Emil Usibelli.

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Figure 1. - Areas described in report.

'
R. I. 4520

Matanuska Valley:

Harry Hill, president and general manager, Evan Jones Coal Co.

Tom McFarlane, superintendent, Evan Jones Coal Co.

Harvey Hiber, assistant superintendent, Evan Jones Coal Co.

Bob Tucker, engineer, Evan Jones Coal Co.

Antone Anderson, superintendent of transportation, Alaska

Railroad.

Emil Phiel, assistant general manager, Buffalo Mining Co.

Frank Colobuffalo, leaseholder, Buffalo Mining Co.

W. W. Stohl, president and general manager, Buffalo Mining Co.

B. D. Stewart, Territorial Commissioner of Mines.

Thanks are extended especially to Ludlow G. Anderson, engineer in charge,

District I, Health and Safety Branch, Bureau of Mines, Anchorage, Alaska, for

cooperation and assistance during the reconnaissance, and to Dr. F. F. Barnes,

geologist in charge of coal investigations in Alaska for the U. S. Geological

Survey, who assisted in the reconnaissance and investigations.

AREAS INVESTIGATED DURING THE EECONNAISSANCE (See fig. 1.)

Matanuska Valley Coal Field

The Matanuska Valley coal field is in the valleys of the Matanuska River

and its tributaries and their separating ridges. This field has been interpreted as being a sunken fault blockl_/ which separated the Talkeetna range

of mountains from the Chugach range. Coal exposures occur in an area approximately 25 miles long by 7 miles wide and parallel the general trend of the

Matanuska Valley. Complexity of geologic structure exists in the area, and

there is a prevalence of igneous intrusions, which appear to increase progressively from west to east. These features, no doubt, have influenced the

rank of the coal. This is true of the high-quality coal found at Chickaloon

on the eastern end of the area.

10/ Chapin, Theodore, Mining Development in the Matanuska Coal Field: U. S.

Geol. Survey Bull. 712(e), 1920, p. 134.

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R. I. 4520

The geology of this coal field has been described in detail.ll/ Briefly,

the Lower Matanuska Valley bituminous coal field occurs in the prominent Wishbone Hill syncline, which extends 7 to 10 miles in a southwesterly direction

from Eska to Moose Creek. Bituminous coal is restricted to the Chickaloon

formation of Tertiary age. This formation, which is below the Eska conglomerates, comprises claystone, siltstone, sandstone, a few thin beds of finegrained conglomerates, and coal beds. These coal beds generally occur in the

upper 1,400 feet of the formation. The Chickaloon formation, below the coalbearing zone, comprises principally dark purplish-gray claystone and silty

claystone. Lateral changes in the thickness of the coal beds and quality of

the coal result in various coal beds being minable at one location and not at

another. The following coal beds in the Matanuska Valley coal field have been

tentatively correlated by the U. S. Geological Survey composite section of

Wishbone Hill syncline showing correlation of beds in various mine areas:

Eska Conglomerate

Chickaloon Formation

Premier mine Buffalo mine Evan Jones mine Eska mine

Jonesville Jonesville Jonesville

coal group coal group coal group

4

3 3 3

2 2 2

1 1 1

0

00

l/ Payne, Thos. G., and Hopkins, David M., Geology and Coal Resources of the

Western Part of the Lower Matanuska Valley Coal Field, Alaska: U. S.

Geol. Survey Mimeograph Report 105117, 1944, 22 pp.

Barnes, F. F., and Byers, F. M., Jr., Geology and Coal Resources of the

Eastern Part of the Lower Matanuska Valley Coal Field, Alaska: U. S.

Geol. Survey Mimeograph Report 113198, 1944, 21 pp.

Tuck, Ralph, The Eska Creek Coal Deposits, Matanuska Valley, Alaska:

U. S. Geol. Survey Bull. 880(d), 1937, pp. 185-214.

Waring, G. A., Core Drilling for Coal in the Moose Creek Area, Alaska:

U. S. Geol. Survey Bull. 857(e), 1934, pp. 155-166.

Martin, G. C., and Katz, F. J., Geology and Coal Fields of the Lower

Matanuska Valley, Alaska: U. S. Geol. Survey Bull. 500, 1912, 98 pp.

Chapin, Theodore, Mining Developments in the Matanuska Coal Field, Alaska:

U. S. Geol. Survey Bull. 712(e), 1920, p. 166.

Paige, Sidney, and Knopf, Adolph, Geologic Reconnaissance in the Matanuska

and Talkeetna Basins, Alaska: U. S. Geol. Survey Bull. 327, 1907, 71 pp.

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R. I. 4520

Eska Conglomerate (Con.)

Premier mine

Premier coal

group

Buffalo mine

Premier coal

group

Evan Jones mine

Premier coal

group

Eska mine

Premier coal

group

1

2

2-1/2

2-1/4

3A

3

4

4-1/2

7

6

5

4

3

2

1

5

6

7

7A

7B

8

9

5

6

Chapin

Maitland group Maitland

David

Emery

9

Powder House

Eska group Eska group Eska group Eska group

Thin bed

10

Thin bed

Eska

Shaw

Martin

New?

Little Eska

group

Little Eska

group

Little Eska

group

Little Eska

group

Evan Jones Mine, Jonesville, Alaska

The Evan Jones mine, which is the only producing mine in the Matanuska

field, is on the Matanuska branch line of the Alaska Railroad at Jonesville,

Alaska. There also is an automobile highway that extends from the mine to

the Glen Highway. Jonesville is approximately 17 miles east of Palmer by

highway and about 58 miles from Anchorage via Palmer. These roads can be

traveled the year around, and, although 36 inches of snow may fall, both the

highways and railroads are kept passable. The railroad operates on a daily

schedule from Anchorage to Jonesville 6 days a week, and a bus line operates

from Palmer to Jonesville.

The output of this mine, which is the largest coal mine in Alaska, came

from two coal beds, No. 5 and No. 3. Mining in No. 5 coal bed was discontinued about July 1, 1946. The ash content of No. 5 coal is above 20 percent,

and the impurities are difficult to remove by washing.12/ The strata overlying this bed are weak and difficult to support. The high ash content of the

coal and the condition of the mine roof were factors leading to the abandonment of operations in this bed. The ash content of No. 3 coal is under 20

percent and roof conditions in the mine are better than in No. 5 bed.

2/ Work cited in footnote 9.

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R. I. 4520

No. 3 coal bed is near the top of the Chickaloon coal formation and

approximately 150 feet below the overlying Eska conglomerate.

No. 4 coal bed, which is approximately 50 feet above No. 3, has been

mined in the south-limb workings and is reported to have been less than 4

feet thick. No. 5 bed is approximately 275 feet stratigraphically below No.

3 bed.

The mine opening is a single drift driven in rock at water level (see

fig. 2). This drift passes through 300 feet of glacial drift and approximately 400 feet of rock and then penetrates the south limb of the coal-bearing

formations of the syncline, which extend for about 800 feet. Six coal beds

were found in this limb of the syncline: the 00, 0, 1, 2, 3 and 4. The main

drift then extends approximately 800 feet north in rock to the coal formatians

in the north limb of the syncline. A crosscut was turned west off the main

drift, where the coal-bearing formations were found, and was driven about 400

feet in rock to the No. 3 coal bed west of the Jonesville fault. The crosscut

to the No. 5 bed was turned to the west off the main drift about 500 feet inby

the crosscut to the No. 3 bed and was driven about 100 feet in rock, where No.

5 coal bed was encountered west of the Jonesville fault. The other coal beds

cut by the main drift as it was driven north across the north limb of the syncline and the approximate interval between the beds as measured in the main

drift are as follows: No. 6 - 100 feet inby No. 5; No. 7 - 100 feet inby No.

6; No. 8 - 300 feet inby No. 7; No. 9 - 160 feet inby No. 8; and No. 10 - 240

feet inby No. 9. The main drift was stopped 350 feet inby No. 10 bed. The

strata between coal beds comprise shaly claystone, sandstone, and siltstone.

The dip of the beds in the south limb of the syncline ranges from 11 to 30

degrees north. All minable coal has been extracted in the beds in the south

limb of the syncline east of the Jonesville fault. This fault crosses the

main adit about 1,400 feet north of the mine workings in the south limb.

The sequence of the beds in the north limb of the syncline is 4, 3, 2, 1,

5, 6, 7, 8, 9, and 10. The dip of these beds ranges from 25 to 35 degrees

south. The coal in bed 8 was developed for about 4,700 feet west along the

strike of the bed, and about 50 percent of the coal above water level was extracted. Mining in this bed was discontinued in 1942. Beds 5 and 6 were developed for approximately 2,700 feet west along the strike, and part of the

coal was extracted. Mining in No. 6 bed was discontinued in 1945 and in No.

5 in 1946.

Present production is from operations in the No. 3 bed in the north limb

of the syncline. The thickness of the bed ranges from 8 to 12 feet. A section of this bed, measured in the No. 8 chute, main gangway, at 18 crosscut,

follows:

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M 0 1 1

-t

.

I..

Figure 2. - General development map, Evan Jones Coal Co. mine, Jonesville, Alaska.
R. I. 4520

Thickness

Description Ft. In.

Roof - claystone ....................................... 2

Roof coal ............................................. 0 5

Hard claystone ......................................... 0 1

COAL .. .. . . .. . . .. . . .. . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . 1 5

Hard claystone ...................................... 0 1/2

COAL .................................... ................... 0 4

Fine sandstone parting ................................. 0 1/2

COAL . . . . . . . . . . . . . . . . . . . . . . .. . .. . . .. . . . . . . . . . . . . . . . . . .. . 1 1

Siltstone, thin coal stringers ......................... 0 2

COAL .. . .. . .. .. . . . . . . . . . ..... D ...... ... 0 5

Siltstone, occasional coal stringers ................... 0 8

COAL ... ............................... 2 5

Hard claystone lense ................................... 0 1/2

COAL ............... ............... .................. 0 5

Claystone lense ...................................... 0 1/2

COAL .................................................. 0 7

Bottom coaly claystone (upper contact breaks well) ..... 1

Bed thickness ............................... ....... 8 1

Coal thickness ......................................... 7 1

The dip of the bed averages 35 degrees in the present workings. The

chute-and-pillar system of mining is used. The haulage entry (gangway) is

driven on the strike of the bed, partly in the footwall, so that the bottom

of the bed is at car height. The entry is driven 8 to 10 feet wide and about

8 feet high. Three-piece timber sets are used to support the roof where necessary. The airway (counter) is 60 feet up the rise from the gangway. Rooms

are turned on 50-foot centers and driven 10 feet wide and about 5 feet high

up the rise on advance for a distance of about 1,100 feet. A block comprises

five rooms. Crosscuts between rooms are on 50-foot centers. After the room

has been driven to its limit, the upper 3 to 7 feet of the bed and pillars

are extracted on retreat. Pillars are extracted by taking off successive

angle slabs. The coal flows by gravity to a chute on the haulageway.

Blast holes are drilled with pneumatic drills, and the holes are charged

with permissible explosives, tamped with sand stemming, and detonated

electrically.

Rooms are advanced by one man, and two men are used in a place in retreat mining. At the time the mine was visited (July 1946), the entire production was from pillars, one gangway, and counter.

Six-ton storage-battery locomotives and steel drop-bottom cars with a

capacity of 3 tons each are used in transporting the coal from the working

places to the tipple.

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R. I. 4520

Ventilation is provided by a propeller fan with a capacity of 40,000

cubic feet per minute. The fan is operated blowing, and the intake of the

ventilation system is on the gangway. The air passes from the gangway to

rooms, travels through the counter, and is exhausted through a room driven

to the surface. There is a steam-driven, 60- by 36-inch, centrifugal fan

for emergency use.

The production of the mine, which averaged 326 tons per day in June

1946, is prepared in a preparation plant. The plus 3-inch coal is handpicked, and the minus 3-inch is washed in a jig type washer. (See fig.

3.) The coal is used by the Army, railroad, and residents of Anchorage.

Power is generated at the mine by a 300-kw., 4 40-volt, 3-phase, 60-

cycle, alternating-current, steam turbine generator. There are two 70-kw.,

440-volt, 3-phase, 60-cycle, Diesel-driven generators for emergency use.

The life of the mine, from present development, is estimated at 3 to 5

years.

Eska Creek Area

The limited life of the Evan Jones mine from present development emphasized the necessity of determining a location for another bituminous coalmine site that could be developed in minimum time. The geology of an area

east of Eska Creek in sections 10 and 15, T. 19 N., R. 3 E., had been studied

by Tuck, Barnes, and Byers, U. S. Geological Survey geologists, and the report on this area was published.l3/ This area is adjacent to the surface

plant of the abandoned Eska mine, which includes a modern washery, power plant,

and shops, arrangements for the use of which possibly could be made with the

present owners of the Alaska Railroad. Barnes and Byers estimate that a potential reserve of 4 million tons of bituminous coal underlies the area. The

reconnaissance indicated that the dip of the beds on the north limit of the

syncline are favorable for mechanized mining, and this area was recommended

for detailed investigation. The minable reserves and physical conditions in

and surrounding the coal beds can be determined only by diamond drilling, and,

as the estimated cost of this investigation was within the funds available,

diamond drilling in this area was undertaken late in the fiscal year 1947 and

was continued into 1948.

Should the investigation by diamond drilling prove minable reserves sufficient for the development of another mine in the Matanuska Valley, this reserve would be a potential emergency source of coal. As only the Evan Jones

mine is producing bituminous coal for Alaska Railroad locomotives, a reserve

source is essential to augment the supply while a modern mine is being developed in Wishbone Hill southwest of Jonesville. The Eska area investigation

was undertaken to utilize the at present idle Alaska Railroad mine plant at

Eska.

E1 Work cited in footnote 11.

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Figure 3. - Surface plant Evan Jones mine.

, " ,,. ,/*' *' '

4 i

Figure 4. - Suntrana mine, Suntrana, Alaska.
R. I. 4520

Wishbone Hill, Southwest of Jonesville

Reconnaissance of an area in Wishbone Hill southwest of the Evan Jones

mine indicates that there are no major faults and that the sequence of the

coal beds is normal for a distance of about 20,000 feet west of the Jonesville

fault in the Wishbone Hill syncline. The geology of this area has been studied and described by Barnes and Byers, geologists of the U. S. Geological

Survey.l4/ The workings in the No. 8 bed, which are in the north limb of the

Wishbone Hill syncline in the Evan Jones mine, were developed for approximately

4,700 feet west of the Jonesville fault without encountering any major faults.

There has been no development, nor have the outcrops been traced, in the

south limb of the syncline west of the Jonesville fault. The outcrops on this

limb of the syncline are covered by glacial drift and slide rock. The Eska

conglomerate, which overlies the coal-bearing Chickaloon formation, is probably about 1,700 feet thick in the central part of the syncline, but on the

south limb this conglomerate has been eroded by glaciation, and intermittent

streams have cut gorges into the conglomerate and decreased the thickness at

these places. The glaciation of the Eska conglomerate has formed a steep escarpment, and the contact of the Chickaloon formation is near the base of this

escarpment.

The necessity for developing a large modern mine in the Matanuska field

is imperative. Loss in production at the Evan Jones mine can be offset partly

by the development of a mine east of Eska Creek, should the investigation now

in progress in that area prove minable reserves. However, the extent of this

deposit is known to be small. The life of a mine east of Eska Creek will be

very limited, and additional sources of bituminous coal should be investigated

by diamond drilling.

The area suggested for investigation is centered approximately in the

NE1/4SE1/4 sec. 19, T. 19 N., R. 3 E. This area is accessible by following

ridges of glacial moraines from the Jonesville road to a ridge between the

escarpment and two lakes. Roads could be built without difficulty on these

ridges.

It is estimated that holes drilled south of and adjacent to the escarpment and the gulches would penetrate the coal beds at an average depth of

1,000 feet. The entire series of coal beds probably would be penetrated at a

maximum depth of 1,500 feet. It is indicated that the lower beds of the

Jonesville group, except the No. 8 bed but including beds 9 and 10, or the

Eska group, decrease in economic value to the west, and the No. 8 or Emery

bed could be established as the basal formation.

Development of minable reserves southwest of Jonesville is desirable for

the future development of the Matanuska coal field. The Matanuska Valley

branch line of the Alaska Railroad will not serve a new mine site adequately

on Wishbone Hill. The present line, which follows the Matanuska River from

Palmer to Sutton, is subject to washouts, and maintenance costs are extremely

4/ Work cited in footnote 11.

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R. I. 4520

high. The capacity of trains is limited by steep grades between Sutton and

Jonesville. Should an investigation determine minable reserves sufficient

for the development of a large mine in Wishbone Hill, the relocation of the

Matanuska branch line from Palmer to Jonesville on higher ground would be

justified and would obviate the hazard of washouts and the steep grades now

existing on this line. This new location also could serve mines that might

be developed on Moose Creek.

Healy River District, Nenana Coal Field

The Nenana coal field is in the northern foothills of the Alaska Range

adjacent to the Nenana River and the main line of the Alaska Railroad. The

southern part of the area is drained by the Healy River and the northern part

by Lignite Creek. Both streams are tributaries of the Nenana River.

The geology of the field has been described by Martinl5/ and Wahrhaftig.l6/

Briefly, the beds of subbituminous coal and lignite occur in the area, which

is characterized by the absence of extreme structural disturbances and igneous

intrusions. The thickness of the beds ranges from 6 to 50 feet, and dips of

10 to 70 degrees are present.

The coal beds are exposed along the banks of Healy Creek for about 12

miles. Both banks of this stream are formed by coal outcrops, which are 20

to 50 feet above the bottom of the stream. The No. 1 bed is the north bank

of Healy Creek for a distance of 4 miles east of Suntrana. An area approximately 6 miles upstream from the Suntrana mine was investigated by the ureau

of Mines, and the results of this investigation have been published.17J

Suntrana Mine, Suntrana, Alaska

The Suntrana mine (see fig. 4) of the Healy River Coal Corp. is on the

north bank of Healy Creek approximately 112 miles south of Fairbanks and 244

miles north of Anchorage. A branch line of the railroad approximately 4-1/2

miles long extends from Healy to the mine.

The main opening is a drift driven at water level through rock. This

drift intersects the various coal beds, which outcrop on the surface and dip

approximately 18 to 28 degrees north. In ascending order, the coal beds are

Nos. 1, 2, 3, 4, 4A, 4B, 5, and 6. The beds considered minable are Nos. 1,

2, 3, 4, and 6. Some mining has been done in No. 5, but the hanging and footwall are soft material and difficult to support and made mining difficult and

costly. The coal beds, in descending order below No. 1 bed, are G, F, to A.

The F bed has been developed from a rock drift, which is upstream from the

J Martin, G. C., The Nenana Coal Field: U. S. Geol. Survey Bull. 664, 1919,

54 pp.

l6/ Wahrhaftig, Clyde, and Friedman, Jacob, Coal Deposits in the Valley of

the Healy River, Alaska: U. S. Geol. Survey Mimeograph Report, 1946.

17/ Marstrander, H., Apell, G. A., Rutledge, F. A., and Hulbert, J. H., Exploration of Leasing Block No. 28 in the Nenana Coal Field, Alaska:

Bureau of Mines Rept. of Investigations 3951, 1946, 21 pp.

3071 - 12 -
__7

R. I. 4520

main opening. The thickness of the beds encountered in the rock drifts is:

Thickness,

Bed feet

1 ......... 50

2 ......... 29

3 ......... 23

4 ......... 12-15

6 ......... 30

F ......... 20

The mine was opened in 1921, and mining has been done underground in most

of the beds. At the time the mine was visited (July 1946), mining was confined

to No. 3 bed. A fire in this bed necessitated sealing it with concrete at the

entry and constructing sand seals inby the fire. The sand seals were constructed by mining the coal and caving the sand in the overlying strata. The

No. 3 bed has been developed inby the seal by driving a crosscut from the gangway in No. 4 bed to No. 3 bed and advancing the gangway along the strike of No.

3 bed. Rooms are turned on 50-foot centers and driven 8 feet wide by 8 feet

high up the pitch for about 200 feet. Crosscuts between rooms are on 50-foot

centers. After two rooms have been developed, the pillar between rooms is

split by driving a room 8 feet wide by 8 feet high. Extraction of the full

thickness of the bed begins at the face of the room by taking successive cuts

off the pillar at about 45 degrees and mining the top coal in rooms. Batteries

constructed of timber are built about every 35 feet. Coal is drawn into chutes

from the battery until a high percentage of cave rock appears. Broken coal is

drawn from the rooms at a rate that will provide height for the men working on

the roof coal. Approximately 2 feet of top coal is left to support the overlying sand during mining. This top coal falls later. The coal is not cut and

is shot off the solid after being drilled with hand-held electric auger drills

and blasted with permissible explosive detonated by fuse and cap.

Usually, the gangways are driven on the strike of the bed to the property

line, and extraction is on the retreat. Electric hoists are used in the rooms

to transport timbers and supplies to the faces.

The coal passes by gravity in steel-lined chutes to steel, drop-bottom

cars in the entry. Loaded trips are transported to the tipple by storagebattery locomotives. The coal is hand-picked and screened to produce 6-inch

lump, nut, and slack coal. The principal consuming area is Fairbanks and

vicinity.

Ventilation is provided by an electrically driven propeller-type fan with

a capacity of 60,000 cubic feet per minute.

The coal, which is subbituminous, is subject to spontaneous combustion,

and a number of underground fires have occurred. These fires have been sealed

with sand barriers.

3071 - 13 -

J
R. I. 4520

Usibelli Strip Mine

The Usibelli strip mine is on the north bank of Healy Creek, about 2-1/2

miles east of Suntrana, Alaska. (See figs. 5 and 6.) Healy Creek is a glacial stream that floods during the spring thaw, spreads over the glacial

gravel bar, and softens the low road. There are two haulage roads from Suntrana to the mine - one on the low gravel bar for summer and fall use, and

one on the higher creek bank for winter and spring use. In the summer, the

high-level road is soft, but in winter, when frozen, it is a good, solid road.

The two roads do not extend the entire distance to the mine; they are used for

the first mile east of Suntrana. A rail siding was built by extending the

main track east, passing the Healy River Coal Corp. tipple tracks at Suntrana.

This siding holds about 10 mine cars and parallels a hogback ridge 200 to 300

feet wide and 75 feet high, which comprises more resistant sediments and forms

a short gorge in Healy Creek. The gorge is passable by fording the stream

with tractors and trucks but is not suitable for continued use. The haulage

road terminates in a "Y" on top of the hogback ridge, and trucks dump into a

loading chute that extends from the top of the ridge to the rail cars on the

siding. There is no storage except in rail cars.

The Usibelli strip mine is operating on an Army-free permit, and all coal

produced is consigned to the Army. The 1946 Army contract purchases 70,000

tons of coal, with provision to increase the contract. The coal is produced

from the No. 1 coal bed, which is 35 feet thick at this mine. The strike is

east-west, paralleling Healy Creek, and the dip ranges 20 to 30 degrees north.

The coal bed is on the north bank and is mined down the dip to water level. A

Diesel-powered shovel is used for loading coal, which is done on a singleshift basis. Stripping in advance of loading is done with bulldozers and by

hydraulicking, which slushes the fine sediments into Healy Creek on a 24-hour,

three-shift basis. The coal bed is uncovered well in advance of mining and it

is estimated that half of this year's production is uncovered (July 1946).

Future development will be toward the east following the coal bed. Portable buildings constructed in sections and bolted together have been erected

at the present mine site. The portable buildings include a central heating

plant, central light plant, boarding house, bunk house, shop, and office. As

operations advance to the east, it is planned to extend the road and move the

portable camp eastward. Eventually, mining will reach Coal Creek and Leasing

Block 28, 8 miles east of Suntrana, which has been described.l8/

The Usibelli stripping is in good operating condition, and if the eastward advance along the outcrop continues, a dependable source of coal will be

developed.

Previous outcrop trenching by the Mining Branch of the Bureau of Mines in

Leasing Block 28 and mapping by the U. S. Geological Survey indicate enough

minable reserves for these stripping operations in this area, and no investigation by diamond drilling at this time to determine minable reserves here is

lT8 Work cited in footnote 17.

3071 - 14 -
"I

it

Figure 5. - Usibelli Strip mine, Healy Creek, Alaska.

Figure 6. - Hydraulicking Usibelli mine, Healy Creek, Alaska.
R. I. 4520

recommended. No attempt has been made to mine the coal beds below the level

of Healy Creek, and this additional coal is available for future development.

Diamond Strip Mine, Healy, Alaska

The Diamond strip mine is about 5 miles S. 52° W. of Healy, Alaska. The

Alaska Railroad has constructed a rail siding to the mine loading ramp, which

is approximately 1 mile north of the Healy railroad station. Healy is 112

miles south of Fairbanks and 244 miles north of Anchorage. A truck haulage

road has been constructed from the car-load ramp to the mine. The road follows glacial moraines and is subject to temporary closure by drifting snow in

winter.

Production in 1946 was 34,911 tons and came from a 40-foot coal bed that

strikes S. 62° W. and dips 33 degrees northwest with the slope of the hill.

Overburden has been removed with a Diesel power shovel and bulldozers. The

coal is loaded with a Diesel power shovel. Approximately 50 feet of clay and

glacial drift will be encountered in the next cut. The strip area was not

properly prepared for mining. Overburden on the first strip-cut was cast downhill and necessitates rehandling of the spoil when subsequent cuts are made.

Future development as a strip mine at the present site is limited by the

greater thickness of overburden and inadequacy of equipment. Trenches and exploration cuts west of the present mine site indicate continuation of the coal

bed in that direction. Further exploration is recommended to the present

leaseholders to outline future mining. Investigation by diamond drilling in

this area by the Bureau of Mines at this time is not recommended.

Lignite Creek Area

There is a large reserve of Tertiary coal-bearing formation along Lignite

or Hoseana Creek. Current and past investigations by the U. S. Geological

Survey indicate duplication of structural conditions and occurrence of coal

found in Healy Creek. This area will be described in a forthcoming report by

the Geological Survey. Lignite Creek is east of the Nenana River and Alaska

Railroad, which is on the west bank of the Nenana River. The area can be made

accessible to rail transportation by the construction of a railroad bridge and

spur into Lignite Creek. This potential source of coal is amenable to development, and the railroad is essential for transportation. The coal in the

Lignite Creek area should be considered in the development of a source of coal

for the proposed cement plant.

Jarvis Creek Area

The Jarvis Creek area comprises about 12 to 15 square miles of Tertiary

coal-bearing formations east of Donnelly, which is on the Richardson highway

and the east bank of the Delta River. The center of this area is about 5 miles

east of Donnelly. Donnelly Dome, which is about 12 miles north of Donnelly, is

3071 - 15 -

. __
R. I. 4520

a prominent landmark. The area is described briefly by Moffit.9 1

/ A tractor

trail begins at Mile Post 244 on the Richardson Highway about 120 miles south

of Fairbanks. This trail continues east to Ober Creek and then southeast to

Jarvis Creek and Little Gold Creek. An older tractor trail begins about 2

miles south of Mile Post 244 and crosses a ridge south of the headwaters of

Ober Creek, thence to Jarvis Creek, and ends at Riley Creek. Both trails are

circuitous and pass east along the north boundary and south along the east

boundary of the Tertiary coal-bearing formation. The area is 5 miles long

north and south and 3 miles wide east and west. It extends 4 miles up the

west bank of Little Gold Creek and 3 miles down the west bank of Jarvis Creek

from their junction and then approximately 3 miles west. The Tertiary coalbearing formation is exposed best in the west fork of Little Gold Creek and

an unnamed creek 1 mile west of Little Gold Creek. This formation is first

encountered in the west side of a low ridge 3 miles east of Donnelly and rises

on a gentle slope to a high escarpment cut by the unnamed creek and the west

fork of Little Gold Creek. The physical features indicate a monoclinal structure with a northeast strike and a northwest dip. The outcrop of alternating

beds of coal, claystone, poorly consolidated or only slightly indurated sand,

and clay on the west bank of the unnamed creek contains an 8-foot coal bed and

several 4-foot coal beds. The occurrence of an 8-foot coal bed indicates an

area of coal. The extent of the deposit can be determined only by diamond

drilling. Charles Hickox and F. F. Barnes, geologists of the U. S. Geological

Survey, were verifying the interpretation of the geology of this area, and no

detailed measurements of sections were made. The area is cut off on the south

by the Birch Creek schist, and the northwest dip was probably caused by the

subsequent elevation of the Alaska Range after deposition of the coal-bearing

formation. The area evidently is an erosional remnant of coal formation in a

basin in older rocks that is bounded on the south and east by older rocks and

covered on the west and north by morainal gravel, in which older rock outcrops

are found as islands. These islands of older rock and the morainal beds also

indicate the edge of the basin. Jarvis Creek has eroded into the basin, and

the remnant of coal-bearing formation becomes the south segment and has monoclinal structure. There were no exposures in which south-dipping beds were

observed.

The most readily accessible and most uniform structure for development is

on the west bank of the unnamed creek. The outcrop of an 8-foot coal bed can

be traced for approximately 1 mile and inferred for 1/2 mile down the dip. A

potential reserve of about 4 million tons of coal is inferred in this bed.

The area could be developed in an emergency after the construction of 10 miles

of new road. The haul to Fairbanks then would be about 135 miles.

1/ Moffit, Fred H., Geology of the Gerstle River District, Alaska: U. S.

Geol. Survey Bull. 926-B, 1942, pp. 107-160.

3071 - 16 -
R. I. 4520

Section of bed in Jarvis Creek area and proximate analysis, as-received

basis.

Description: Outcrop at head of small creek entering Jarvis Creek a short

distance below Little Gold Creek.

Ft. In.

X Shale .......................... 3 0

COAL ...... .................. .. 4 6

X Shale .......................... 8

COAL ........ ................. 1 0

X Shale .........................

Thickness of coal ........... 5 6

Thickness of bed ............ 6 2

X = excluded from sample.

Percent

Moisture ................. ... 23.0

Volatile matter ............. 39.8

Fixed carbon ................ 24.1

Ash .......................... 13.1

Sulfur .................. ... 1.4

B.t.u ....................... 7,815

Description: Outcrop at elevation, 3,780 ft. N. 700 W. of forks of Little

Gold Creek. (See plate 3, U. S. Geol. Surv. Bull. 926-B.)

Ft. In.

X Sandstone ...................... 25

X COAL ..... ... ................ . 1 6

X Shale ......................... 1 1

COAL ........................... 6 3

X Sandstone ...................... 6

X Shale, thin coal ...............

Thickness of coal sample .... 6 3

Thickness of bed ............ 8 10

X = excluded from sample.

Percent

Moisture ....................... 20.0

Volatile matter ............. 43.4

Fixed carbon ................ 25.8

Ash ..................... 10.8

Sulfur ...................... .4

B.t.u ........................ 8,645

3071 - 17 -
R. I. 4520

Description: Outcrop elevation, 3,750 ft. N. 69° W. of forks of Little Gold

Creek. (See plate 3, U. S. Geol. Surv. Bull. 926-B.)

Pt. In.

Sand ......................... .

COAL ............................. 4 10

Shale, little coal ..............

Thickness of coal ........... 4 10

Thickness of bed ............ 4 10

Percent

Moisture .................... 20.6

Volatile matter ........... 38.9

Fixed carbon .................. 35.3

Ash ......................... 5.2

Sulfur ...................... .4

B.t.u. . ................... 9,415

Mt. McKinley Park Area

There are several small and irregular isolated coal areas in the vicinity

of Mt. McKinley Park. The coal beds are found in two geologic periods - the

Cantwell formation of the Cretaceous period and the coal-bearing formation of

the Tertiary period. There has been no sustained production of coal from the

Cantwell formation, but it has been prospected and tested near the Alaska

Railroad. The following areas were investigated in 1946:

1. In the vicinity of Mile Post 341.

2. On Riley Creek west of Mt. McKinley Park station.

3. At the headwaters of the east form of Moose Creek and Boundary

Creek.

4. Between the west fork of Stoney Creek and the east fork of Moose

Creek.

Mt. McKinley Bituminous Coal Mine, Yanert, Alaska

(Also known as Yanert Mine) (See Fig. 7.)

This mine, which is about 6 miles south of Mt. McKinley Park station at

Mile Post 341 on the Alaska Railroad, was in operation about 1915 and has been

abandoned. The main entry is about 1,200 feet west and about 400 feet above

the Alaska Railroad track. An old sketch plan shows that the main gangway entry was driven along the strike for a distance of 700 feet. At approximately

100 feet inby the portal, Counter No. 1 was turned up the dip and driven 54

feet, where the counter was turned to follow the strike of the bed. Seven

chutes were driven from the main gangway to the counter. The first chute was

driven to the surface for ventilation. Chutes 4, 5, and 6 were driven up the

dip from 50 to 100 feet above the counter. Production was small, but one

railroad car was shipped to Nenana and tested in the steam plant. It was reported that the test proved the coal to be unsatisfactory because clinker was

formed, which covered the entire grate in the boiler. The entry had caved at

the portal and was not open in 1946. The sketch of the mine shows a branch

3071 - 18 -
Figure 7. - Area adjacent to north boundary McKinley National Park.

--
R. I. 4520

in the main gangway 500 feet inby the portal and also a curve in the counter,

which indicates a faulted, folded, or abnormal condition. The probable strike

is indicated to be S. 70° W. and the dip from 400 to 60° North.

A caved surface prospect pit, which showed coal in the dump, was found

about 1/2 mile west of the main entry on top of the first ridge. The outcrop

of the bed was concealed. The outcrop of the roof rock was nearby, and this

rock was classified as a felsitic dacite of igneous origin and therefore intrusive, subsequent in age, and likely to cut across the bedding of the older

sedimentary coal beds.

Coal bloom was observed 1-1/2 miles west and 2 miles east of the main entry on the east and west sides of a north-south gulch. The actual outcrops

were not uncovered, and the bloom was intermittent and covered by recent surface erosion.

The surface outcrops were highly weathered, but a general structural

trend was indicated in an east-west direction. The coal formation was identified as Cantwell formation of Cretaceous age, which generally comprises thin

coal beds, sandstones, gray claystone, black claystone, and conglomerates.

None of the thin coal beds appear to be minable, and no mining is known in the

Cantwell formation in this locality.

In the vicinity of Mile Post 342, a black claystone with thin streaks of

coal 1/8 inch thick was observed. From a distance, the outcrop appears to be

coal, but upon close examination no coal of commercial importance was found.

The Mt. McKinley bituminous coal mine dump consisted chiefly of coal and

coaly claystone, which was extracted during the development of the gangway,

counter, and chutes in the mine. The dumps were large and indicated a thick

parting of claystone. A grab sample of this coal and coaly claystone was

taken, and the analysis, as-received basis, follows:

Percent

Moisture ...........................

Volatile matter ................... 19.8

Fixed carbon ...................... 39.9

Ash ................................ 25.9

B.t.u .... ...................... 9,570

The Yanert mine or Mt. McKinley bituminous coal mine has the following

description in "Analyses of Alaska Coals":20/

Analyses 94166 to 94169 (p. 30). Medium volatile bituminous

and weathered coals, Mount McKinley National Park district, from

Yanert mine, 1 mile from Yanert siding. The bed was sampled at

three points by J. A. Davis (U.S.B.M.), August 8, 1923.

207 Bureau of Mines, Analyses of Alaska Coals: Technical Paper 682, 1946,

p. 75.

3071 - 19 -
R. I. 4520

Sample 94166 (weathered) was a grab sample taken in upper

counter. Sample 94167 was taken at breast of main tunnel 420

feet from portal, and Sample 94168, at breast of counter 380

feet from portal.

Analysis

94169

(composite

94166 94167 94168 94166-68)

Moisture ................................. 7.7 4.2 5.9 5.0

Volatile matter ......................... 11.4 24.2 18.6 21.0

Fixed carbon ............................ 64.7 59.7 56.8 58.8

Ash ....................... *....... 16.2 ...... 11.9 18.7 15.2

Sulfur .................. ................. 7 .4 .4 .4

Hydrogen ................. ........ - - - 4.2

Carbon .................... . .... .... -.. - - 67.4

Nitrogen ... - ............. ........ ...- - 1.0

Oxygen ............ ..................... - - - 11.8

B.t.u ............... #* ......... ...... 11,050 12,180 10,590 11,350

Initial deformation temperature, °F. .... 2,110 2,280 2,190-

Softening temperature, OF. .............. 2,390 2,510 2,390

Fluid temperature OF. ..................... 2,450 - 2,510

Riley Creek

Riley Creek is south and west of McKinley Park station. A small production of blacksmith coal was reported from this area around 1915. The Cantwell

coal formation is present. Thin stringers of coal and blackstone were observed.

Production from this area was very small, and no activity has been reported

since 1915.

Moose Creek and Boundary Creek

The east fork of Moose Creek, Boundary Creek, and the west fork of Stoney

Creek all have their headwaters in the same general area, which is about 10

miles northwest of Highway Pass on the Mt. McKinley Park highway. There are

isolated outcrops of Cretaceous Cantwell coal formation in this general area.

The divide separating these creeks is partly covered with recent gravel, but

outcrops of coal bloom were found on the east fork of Moose Creek and Boundary

Creek. The general attitude of the beds is approximately vertical with an

east-west strike. The coal bloom could not be traced continuously along the

strike, though small disconnected bloom showings were observed. There were no

distinct outcrops or prospects. There was much surface slumping, which also

obscured the trace of the bed. However, marmots and ground squirrels had dug

up coal in their burrows. The adjacent area on the headwaters of Stoney Creek

was of like nature, and no minable coal was observed. The area is inaccessible

and of no commercial value.

Tertiary Coal-Bearing Formation (Nenana)

The coal-bearing formation of the Tertiary age extends westward from the

Alaska Railroad belt for 25 to 30 miles along the north boundary of Mt. McKinley

3071 - 20 -
2

R. I. 4520

Park. There are several small areas of coal-bearing formation within Mt.

McKinley Park. Many of the outcrops were visited, sections were measured,

and coal beds sampled. The coal-bearing formation outcrops are most complete

and typical along Healy Creek in the vicinity of Suntrana, where a stratigraphic thickness of 1,900 feet has been measured and described as consisting

of little consolidated, poorly consolidated, or only moderately indurated,

gravel, shale, claystone, sand, and subbituminous coal beds. The coal beds

in the Tertiary coal-bearing formation are classified subbituminous C and

have been mined for many years along Healy Creek, where they are thick enough

for development and where they are within 5 miles of the railroad. The coalbearing formation was lain in basins or fresh-water lake areas on the unconformable surface of the pre-Cambrian Birch Creek schist. The basal beds of

the coal-bearing formation consist of several hundred feet of smoothly rounded

pebbles of chert and white quartz in a matrix of white sand and kaolinitic material with a conspicuous white color that readily identifies the base. Above

the white basal gravel are alternating beds of claystone, clay, sand, and coal.

Conformably above the coal-bearing formation is found the thick Nenana gravel

and also irregular recent gravel of Quaternary age. The area investigated

along the north boundary of Mt. McKinley Park includes the valleys and gorges

of the Savage, Sanctuary, Teklanika, and Sushana Rivers. The general trend

of these rivers is north and south, and they have east and west tributaries

that have north and south tributaries, but all of these rivers flow from south

to north away from the Alaska Range glaciers and snow banks. The coal-bearing

formation within Mt. McKinley Park outcrops in small structural basins along

the McKinley Park highway and is found mostly along the Toklat River and tributaries. Two of the structural basins are separated by an outward range of

low mountains of the main Alaska Range. The low mountains are erosional remnants of pre-Cambrian Birch Creek schist in which the drainage pattern was

formerly east and west, but elevation and formation of the Alaska Range in

late Tertiary time after deposition of the early Tertiary coal-bearing formation changed the drainage pattern to north and south. This change has developed the gorges and river valleys of the piesent'time. Deformation of coal

beds was greater along the McKinley Park highway, and steeper dips are found

there. Deformation is less along the north boundary of Mt. McKinley Park,

and the dips are less.

The areas along the Mt. McKinley Park highway are most accessible but

subject to National Park regulations pertaining to preservation of scenic features. The area along the north boundary of Mt. McKinley Park is accessible

on foot or horseback. Horses are scarce, and foot travel is commonly used,

though supplies can be taken in by pack train, and personal gear can be carried in back packs. One trail starts at Lignite and follows ridges west and

is known as the old Cantishna trail. A second trail starts from the McKinley

Park highway and follows the Savage River through the gorge to the boundary

and is known as the Savage River trail. Horses are available at Lignite, and

pack trains use the Cantishna trail. Foot travel is best via the Savage River

trail. Transportation is available to the beginning of the Savage River trail.

There is a choice of routes along the north boundary of McKinley Park. Two

base camps were used. The Park Ranger shelter cabin was used as one base camp,

and the second base camp, which was taken in by pack trains, set up on the

3071 - 21 -
R. I. 4520

Teklanika River. Spike camps, or temporary shelters, were back-packed from

the base camps and set up near areas that were to be studied.

North Boundary of Mt. McKinley Park

The area along the north boundary of Mt. McKinley Park includes the

Savage, Sanctuary, Teklanika, and Sushana Rivers. Sections of coal beds in

the Tertiary coal-bearing formation were measured in an area about 3 miles

north and south and 15 miles east and west.

Savage River. - The outcrops along the Savage River are on the eastern

side of the area. The following section of coal-bearing formation was measured on the north bank of Ewe Creek, three-tenths mile east of the Savage

River and 2-1/2 miles south of the north boundary of Mt. McKinley Park (see

fig. 7, loc. 1), approximate elevation 2,400 feet, strike N. 50° E., dip 12°

NW.

Thickness

Description Ft. In.

X Terrace and stream gravel (Quaternary) ............ 1-20 +

COAL (analysis C-64425) .......................... 7 10

X Poorly consolidated sand ....................... .*. 20 +

X Coal and coaly claystone .......................... 2 0

X Covered, sand and gravel (Quaternary) .............. 2 +

Members marked (X) excluded.

Analysis C-64425, as-received basis:

Percent

Moisture ....................................... 26.3

Volatile matter .................................... 35.1

Fixed carbon .................................... 25.1

Ash ............... .............. ... . . 13.5

Sulfur ..................................... ... .4

B.t.u. ....................... ....................... 9,850

Birch Creek schist, which underlies unconformably the coal-bearing formation and cuts off this formation, outcrops on the south bank of Ewe Creek

100 feet from this section.

The following section of coal-bearing formation was measured on the west

bank of the Savage River, 2 miles south of the north boundary of Mt. McKinley

Park, 1/2 mile north of the mouth of Ewe Creek (see fig. 7, loc. 2), approximate elevation 2,300 feet, strike N. 50° E., dip 15° NW.

3071 - 22 -
R. I. 4520

Description

X Terrace gravel (Quaternary) ......................

COAL (analysis C-64424) ..........................

X Poorly consolidated sand .........................

X Covered with terrace gravel (Quaternary) .........

Thickness

Ft. In.

50 +

13 1

1 +

O Members marked (X) excluded.

Analysis C-64424, as-received basis:

Moisture ................. ..............

Volatile matter ..................................

Fixed carbon .....................................

Ash ..............................................

Sulfur ...........................................

B.t.u..........................................

Percent

31.5

36.4

28.0

4.1

.1

7,530

The following section of coal-bearing formation was measured on the west

bank of the Savage River 500 feet north of the north boundary of Mt. McKinley

Park (see fig. 7, loc. 3), strike N. 60° E., dip 150 S.

Description

X Sand and gravel ..................................

X Claystone .........................................

COAL (analysis C-64423) .........................

X Bottom, not exposed, coal bed 13' 6" plus.

Thickness

Ft. In.

25 0

1

13

+

6

Members marked (X) excluded.

Analysis C-64423, as-received basis:

Moisture ................................ .....

Volatile matter ..................................

Fixed carbon ....................................

Ash ........................ ........................

Sulfur ...........................................

B.t.u. ...........................................

Percent

28.9 2--8V

31.2

24.0

15.9

.4

6,320

North of this outcrop is an area in which are many slump blocks of coal

but no outcrops in place. The general structure is flat-lying monoclinal beds

with east and west strike and 100 N. dip, with an anticlinal and then a synclinal roll. Detailed mapping by the Geological Survey will clarify the structure. This slump area continued northward for approximately 1 mile to a cliff

exposure of alternating coal beds and poorly consolidated sand, clay, and claystone. The coal beds strike east-west and dip 10° N. The cliff exposure is

approximately 1,000 feet long and 100 feet high. The beds were faulted with

a 10-foot upthrow on the north side of the fault at about 200 feet from the

3071 - 23 -
R. I. 4520

north end of the exposure. The upper coal bed appeared to decrease in thickness from 6 feet 1 inch to 4 feet 5 inches, which may have been caused by

surface erosion, though lenticular coal beds are common.

The following section of coal-bearing formation and three minable coal

beds were sampled by going up-dip from north to south along the cliff flanking the Savage River, starting 1 mile north of the north boundary of Mt.

McKinley Park on the west bank of the Savage River (see fig. 7, loc. 4), at

an elevation of approximately 2,000 feet, strike east and west, dip 9° N.

a

Description

X Terrace sand and gravel ..........................

X Coal, highly weathered ...........................

COAL (analysis C-64420) .........................

X Claystone and some fine sandstone .............

X COAL .............................................

X Claystone .......................................

COAL (analysis C-64421) ........................

X Claystone .......................................

COAL (analysis C-64422) ..........................

X Claystone ......................................

Thickness

Ft. In.

10 +

1 8

4 5

20 0

1 8

0 9

6 0

1 6

8 8

2 0

Analysis of the above coal beds, as-received basis, follows:

Analysis percent

C-64420 C-64421 C-64422

Moisture ............... 28.4 27.9 31.5

Volatile matter ........ 33.3 34.4 35.9

Fixed carbon ........... 24.3 23.3 25.6

Ash .................... 14.0 14.4 7.0

Sulfur ................. 3 .3 .2

B.t.u. ................. 6,740 6,820 7,070

The coal in these samples was weathered to some degree.

Sanctuary River. - The Sanctuary River is approximately 5 miles west of

the Savage River and flows through the area along the north boundary of Mt.

McKinley Park.

A section of coal-bearing formation was measured along the east bank of

the Sanctuary River. Outcrops were exposed in a bank 20 to 50 feet high. The

dip of the strata was steep, and several coal beds were exposed. The location

of the section is 1 mile south of the north boundary of Mt. McKinley Park (see

fig. 7, loc. 5), approximate elevation 2,000 feet. The beds were measured

from the top bed on the north to the lower beds on the south, and intervals

were measured perpendicular to the dip to give the true interval. The high

dips are due to deformation by mountain building on the south and by the uplift of the older pre-Cambrian Birch Creek schist south of the outcrop that

occurred after the deposition of the coal-bearing formation.

*

3071 - 24 -
__

R. I. 4520

Section as follows, top, north, measured to south:

Thickness

Description Ft. In.

Terrace sand and gravel .............................. 50 +

Claystone ,........................................ 1 +

COAL ........................................ 3 10

Covered (claystone and sand) ......................... 25 0

COAL ................................................. 1 4

Claystone ............................................ 0 3

COAL ............................................ . 0 10

Claystone ............................................ 0 5

COAL ..................... .. .............. ...... 3

Claystone ............................................ 3 0

Poorly consolidated sand ...........................12 0

Claystone .............. ..................... 2 0

COAL (strike N. 65° E., dip 53° N., analysis C-64417). 2 10

X Sandy claystone with pebbles .........................0 8

COAL (dry, partly weathered, analysis C-64417) ....... 2 0

Claystone ........................................... 4 0

COAL 0 ............................................ 1 8

Claystone (upper 20 ft. covered) ....................... 40 0

Poorly consolidated sand ............................. 20 0

COAL (dry, partly weathered, analysis C-64418) ......... 4 9

Micaceous claystone (strike N. 60° E., dip 40° N.) ... 1 +

Covered ............................................... 100 +

COAL ................................................. 2 0

Covered ............................................... 1 +

Analysis on as-received basis follow:

C-64417, C-64418,

percent percent

Moisture .............................. .. . 28.6 30.9

Volatile matter ....................... 35.5 32.4

Fixed carbon ....... ........ ....... 22.7 23.5

Ash .. ....... ... ....... 13.2 13.2

Sulfur ..... ...... .... .. ........ 3 .3

B.t.u. ..... ......................... 6,810 6,560

Teklanika River. - The Teklanika River is approximately 2 miles west of

the Sanctuary River and flows through the area along the north boundary of

Mt. McKinley Park.

The following section of coal-bearing formation was measured on the north

bank of the west branch of the Teklanika River 2 miles west and 3 miles south

3071 - 25 -
_ __ _____ _ 

R. I. 4520

of point where the Teklanika River crosses the north boundary of Mt. McKinley

Park. (See fig. 7, loc. 6.)

Approximate elevation, 2,250 feet. Section measured from top, north to

south.

Description

Quaternary terrace gravel ..................

COAL (No. 4 bed, analysis C-64416) .........

Poorly consolidated sand ...................

COAL (strike N. 70° E., dip 15° N.) ........

Poorly consolidated sand ...................

COAL (No. 3 bed, analysis C-64415) .........

Sandy claystone ............................

Poorly consolidated sand ...................

COAL .......................................

Poorly consolidated sand ..................

Claystone with thin coal beds ..............

COAL (No. 2 bed) ...........................

Claystone .................................

Poorly consolidated sand and conglomerate,

two thin coal beds .......................

COAL (No. 1 bed) ...........................

Poorly consolidated basal conglomerate .....

Analysis of samples taken in the above section on

follows:

C-64416,

percent

Moisture ..................... 27.7

Volatile matter ................. 39.8

Fixed carbon ................. 26.6

Ash .......................... 5.8

Sulfur ............................ .2

B.t.u. .................. ..... . 7,631

Thickness

Ft. In.

10-90

8 o

8 0

1 0

5 0

7 0

3 o

4 0

1 2

10 0

10 0

2 1

5 0

*

30

3

20-90

0

2

as-received basis, as

C-64415,

percent

28.7

36.0

25.6

9.7

.3

7,150

I

Sushana River. - The Sushana River, which is the west boundary of the

area along the north boundary of Mt. McKinley Park, is 5 miles west of the

Teklanika River. This area extends about 15 miles east and west from the

tributaries of the Savage River to the tributaries of the Sushana River. The

west bank of the Sushana River is mostly Nenana gravel, which overlies the

coal-bearing formation.

The following section of coal-bearing formation was measured on the second south tributary of the east tributary 1/2 mile south and 1 mile east of

the Sushana River. (See fig. 7, loc. 7.) The east tributary flows into the

main Sushana River 3 miles south of the north boundary of Mt. McKinley Park.

The approximate elevation where section was measured is 2,950 feet.

3071 - 26 -
R. I. 4520

Description

Quaternary terrace gravel ................

Poorly consolidated sand ..................

Claystone .................................

COAL (No. 4 bed (?), analysis C-64419,

strike N. 80° E., dip 9° N., dry, partly

weathered) ..............................

X Claystone .................................

Terrace gravel ............................

X COAL (estimated thickness, 15 ft., exposed

3 ft., covered with stream and alluvial

gravel) .................................

Members marked (X) excluded from sample.

Analysis C-64419 on as-received basis, follows:

Thickness

Ft. In.

50 +

2 0

8 8

1 0

20 +

3 +

Percent

Moisture .................................. 32.7

Volatile matter ........................... 37.9

Fixed carbon .............................. 23.9

Ash ....................................... 5.5

Sulfur ........................................... .2

B.t.u ..................................... 7,090

A continuation of the measured section on this south tributary was observed

in the next south branch of the east tributary. The coal beds shown in the following section were in slump blocks, which were deeply covered and badly weathered.

Description

Quaternary sand and gravel ................

COAL .....................................

Poorly consolidated sand and gravel .......

COAL . . . . . . . . . . . . .. .. . . . . . . . . . . . . . . . . . . . . . .

Poorly consolidated sand and gravel .......

COAL ......................................

Covered, sand and gravel ..................

COAL ......................................

Covered, sand and gravel .................

COAL .. . . . . . . .. .. . . . .......................

Sand and gravel ...........................

Rounded chert and white quartz pebbles of

basal coal-bearing formation ............

Pre-Cambrian Birch Creek schist ...........

Thickness,

feet

50+

4

20+

8

25+

8

50+

6

50+

5

20+

100+

100+

The pre-Cambrian Birch Creek schist is the unconformable old land surface

on which the coal-bearing formation was deposited and marks the boundary and

basal limits of the coal-bearing formation. Erosion remnants of Birch Creek

schist indicate the absence of coal-bearing formation and are generally found

at higher altitudes.

3071 - 27 -
R. I. 4520

The area of coal-bearing formation along the north boundary of Mt. McKinley Park is about 20 miles long, east and west, and extends about 5 miles

north and south and contains several coal beds of minable thickness. The terrace gravel of Quaternary age and tundra grass obscure and cover the area between coal outcrops, and none of the coal beds can be traced from outcrop in

one river to outcrops in the next river, but a continuity is suggested. The

U. S. Geological Survey will describe and map the area in detail. The minable

coal beds in this area are situated 12 to 25 miles west of the Alaska Railroad

and 6 to 10 miles north of the Mt. McKinley Park highway.

No development by the Bureau of Mines of minable reserves in this area is

recommended at this time because of inaccessibility.

Mt. McKinley Park Highway (See fig. 7.)

There are several areas along the Mt. McKinley P-ark highway in which coalbearing formations of Tertiary age are found. These areas are described in

reference to mile posts from McKinley Park station west along the highway,

streams, and passes. The best-exposed outcrops of coal beds are along the

Toklat River. The coal-bearing formations along the highway were deformed by

the elevation of the Alaska Range and related mountains flanking the main

range. Steep dips and vertical beds are common. Sable Mountain, Polychrome

Pass, Highway Pass, and Thorofare Pass comprise igneous intrusions that were

intruded in the mountain building. The intrusion of these igneous rocks was

a direct cause of deformation that resulted in steep dips in the sedimentary

coal-bearing formation.

Mile Post 39. - The following section of coal-bearing formation was measured 200 feet above and 1/2 mile north of Mile Post 39 on the Mt. McKinley

Park highway west of Sable Mountain. (See fig. 7, loc. 8.) The outcrop can

be traced for 1,400 feet along a strike N. 80 W. The dip is 60° south. The

large outcrop is visible from the road, and the meadow between the outcrop and

the road is usually inhabited by one or two Toklat grizzly bears, which are a

menace to intruders.

Thickness

Description Ft. In.

Terrace sand and gravel .................. 10

Coal, highly weathered .................... 10 +

Clay and sand .......................... 6

COAL (analysis C-64413) ................... 26 6

Poorly consolidated sand ... ...............1 +

Sand and gravel ........................... 100

Analysis C-64413, as-received basis, follows:

Percent

Moisture ........... ....................... 32.0

Volatile matter .......................... 34.6

Fixed carbon ...............,.... ... 24.1

Ash ....................................... .. 9.3

Sulfur ................................... .3

B.t.u ................................... 6,610

3071 - 28 -
R. I. 4520

The site is within half a mile of the Mt. McKinley Park highway and

could be developed readily in an emergency, but development of a mine within

the park is restricted.

Mile Post 42. - The Alaska Road Commission operated a mine on the east

fork of the Toklat River at Mile Post 42. The entry was open in coal for 300

feet but was very wet, and the timber was rotted. It was unsafe to enter the

old unventilated rooms. The strike of the bed was N. 70° E., the dip 300

south, and the altitude approximately 3,700 feet. Production from this mine

was small and probably stopped 10 years ago. Selective loading was practiced,

picking out claystone by hand and screening out the slack, which was either

gobbed in the mine or wasted on the dump. It was reported that without circulation of air, the roof was frozen and was strong, but after an airway was

opened and air circulated, the frozen roof thawed and caved. The following

section of coal-bearing formation was measured on the outcrop (see fig. 7,

loc. 9):

Description

Terrace sand and gravel ....................

Claystone ...............................

COAL (C-64414) .................... ...

X Coaly claystone ...........................

COAL (C-64414) ............................

X Claystone ......................................

X Coal and coaly claystone ..................

COAL (C-64414) ............................

X Sandy claystone ........................

Sand and gravel ...........................

Members marked (X) not included.

Analysis C-64414, as follows:

Moisture ................................

Volatile matter ...........................

Fixed carbon ...............................

Ash .......................................

Sulfur .............. . ..................

B.t.u. .....................................

Thickness

Ft. In.

10-50

5 0

2 9

0 1

3 9

2 0

1 6

7 2

1 +

50 +

I

Percent

23 . 35.6

33.2

7.6

.4

8,350

The following section of coal-bearing formation was measured on the north

side of the east fork of the Toklat River adjacent to and 1/4 mile east of the

Old Alaska Road Commission mine, approximate altitude 3,800 feet, strike N.

80° E., dip 30° S.

3071 - 29 -
R. I. 4520

Description

Terrace gravel ...........................

COAL ....................................

Poorly consolidated sand ..................

Coaly claystone .........................

COAL ... .....................................

Poorly consolidated sand ..................

COAL. ....................................

Poorly consolidated sand ... ............

Covered ............. ..................... ...

Thickness

Ft. In.

10-50

4-5 0

5 0

3 0

3 0

7 0

4 6

1 +

50 +

This coal section probably represents beds below the section of the Alaska

Road Commission mine. Coal-bearing formation was observed east of this section,

but there were no minable outcrops. Coal could be mined at this section but the

beds would require exploration to determine the extent.

Polychrome Pass. - Crossing the main east fork of the Toklat River and continuing up the west fork of the Toklat River and south of the highway, almost

vertical coal beds were observed. The following section was measured on the

south bank of the west fork of the east fork of the Toklat River south of Polychrome Pass at gravel bar elevation 3,700 feet, strike N. 80° E., dip 80° S.

to vertical, measured south to north or top to bottom.

Description

Terrace sand and gravel ...................

Claystone .................................

COAL *. . .. .***.** . .... . .... .... . ....

Claystone, coaly on north side ............

Coaly claystone ...........................

COAL *...... ................... ............

Coaly claystone ............................

COAL ......................................

Gray claystone ........ ................

COAL .............. ........ .............

Clay ......................................

COAL ... .. .................. .... .... ......

(Continuing west and north)

Claystone and siltstone .............. ...

Coaly claystone and coal interbedded ....

COAL ... *........ ............ e .... .... ..

River gravel ..............................

Quartz porphyry and andesite ............

Thickness

Ft. In.

10-50

1 +

4

7

1

0

0

0

1 9

0 6

2 6

0 6

3 0

1 0

2 0

S

6

60

28

500

2,000

6

0

0

0

0

The uppermost coal bed, 28 feet thick, was 500 feet from the outcrop of

the intrusive porphyry and andesite, but the deformation from the intrusion

and heat from the igneous rock had not caused any apparent metamorphism.

These coal beds are not minable because they do not extend over 20 feet above

the river bar and are too near the river to develop.

3071 - 30 -
R. I. 4520

There is an area of coal formation near Highway Pass, but no coal beds

of minable thickness were observed.

The area, a half mile north of Mile Post 39, in which the 26-foot 6-inch

coal bed with 9.3 percent ash occurs, is the most suitable for an emergency

source of coal for Mt. McKinley Park. The Mt. McKinley Park highway is an

all-weather road with good bridges and crossings on the Teklanika and Savage

Rivers. Development of a mine and transportation of coal over the highway

would be subject to National Park regulations and approval. Surfacing material for road maintenance and construction is available.

Kenai Peninsula in Vicinity of Homer

An increase in the demand for coal in the Kenai Peninsula is anticipated

because of the increase in population due to the agricultural development of

the area and the construction of new highways. Numerous outcrops of coal beds

were reported on the peninsula, and the development of modern mines in this

area would furnish an additional supply of coal for domestic use and for the

Army at Fort Richardson. This additional supply of coal would obviate dependence on supplies from the Matanuska field. Modern mines cannot be developed

economically unless the minable reserves and physical and chemical characteristics of the coal are known, and a preliminary reconnaissance of some areas

on the peninsula in the vicinity of Homer was made in cooperation with a geologist of the U. S. Geological Survey.

The area has been subdivided into sections and opened for homesteading.

Homer, which is about 120 air miles southwest of Anchorage, is a small hamlet

on Kachemak Bay adjacent to Cook Inlet and is the center of activity in the

area.

The topography is marked by two prominent plateaus or benches. The first

bench slopes gently from the mud flats of the coast to the base of a bluff,

which is about 300 feet elevation. There is a gradual rise from this bluff,

which parallels the coast of Coal Bay, to an altitude of about 500 feet at the

second bench. The distinction between the two benches disappears when the

coast is formed by a perpendicular cliff 200 to 300 feet high, though a benchlike topography is general and very distinctive. Streams have eroded long,

deep canyons into the second or upper bench.

The Kenai coal formation is found along the northwest coast of the Kenai

Peninsula and extends several miles inland. It consists of poorly consolidated

sand, clay, claystone, and coal beds. The coal beds dip to the northwest, are

the most resistant to erosion, and are a capping on the sediments and result

in waterfalls in the stream bottoms and canyons. The canyons are gently sloping between waterfalls and sometimes open as basins. The coal beds are exposed

in the waterfalls, perpendicular walls of the canyons, or benches. The coal

beds were not correlated from canyon to canyon, but bed correlation by detailed

mapping or plane table surveying will be done by the U. S. Geological Survey.

There is some evidence of glaciation, but there are no large morain deposits.

Occasionally, areas of reddish sediments and clinkered claystone mark local or

continuous zones in which coal beds have been burned. No burning coal beds

3071 - 31 -
R. I. 4520

were observed, though in winter there is evidence that some of the beds are

burning beneath the surface. Some of the coal beds are of minable thickness,

and each homestead has an accessible source of fuel either within the homestead or adjacent to the homestead. In several instances, houses were built

very close or adjacent to a coal bed that was hand-mined for fuel.

The area near the vicinity of Homer has been developed by graded and

graveled roads that comprise a main road along each bench and two roads connecting the upper and lower benches. Roads in sandy or gravel areas do not

require surfacing, and this condition is most typical of the upper bench. In

addition to the main roads, there are farm roads that extend to the base of

the second bench and into some of the canyons. The canyons are easily traversed on foot, and there are trails in some of them. A waterfall can be

easily circled or by-passed.

Vegetation comprises grass and weeds 3 to 4 feet high, spruce, cottonwood, and willows. The cottonwoods are as much as 40 feet high in protected

basins but disappear as the altitude increases. Willows and spruce continue

up the slope but are most plentiful on protected or leeward slopes. The lower

bench land is the most arable, principally because of the lower altitude,

which lengthens the growing season. Potatoes, root vegetables, celery, lettuce,

cabbage, strawberries, and hay are grown. Livestock consists of horses, cows,

and sheep, though total livestock is limited by the scarcity of winter feed and

hay.

The canyons traversed are described. No attempt is made to correlate the

coal beds exposed in these canyons except where correlation is obvious. The

area will be mapped by the U. S. Geological Survey to show coal beds in detail,

and the beds will be correlated at that time.

The first traverse was made in Bidarki Creek, which is west of the Homer

Coal Corp. mine. The mouth of Bidarki Creek is on the beach, but a 200-foot

cliff at the beach forms a waterfall from the top of the cliff. (See fig. 8,

loc. 1.) Several coal beds strengthen the cliff and cause it to be perpendicular. The Cooper coal bed, which is 6 feet, 4 inches thick, is 50 feet

above the beach. There are several thin coal beds above and below the Cooper

bed.

The top of the cliff, 200 feet above the beach, is a coal bed 7 feet 6

inches thick with interbedded claystone and coal. A section of this bed,

which is about 150 feet above the Cooper bed, measured at the outcrop, 1,000

feet west of the Homer mine, is as follows (fig. 8, loc. 2):

3071 - 32-

. . ..
P t

Iq * C

I , I i x Ii /

-to tfrt

Figure 8. - Sketch map, Homer-Kenai peninsula area.
R. I. 45ao

Thickness

Description Ft. In.

X Light-gray clay ........................... 3 +

X Interbedded thin claystone and thin coal. 1 5-1/2

X Claystone .............................. 1 1

* COAL ............. .................. 2 0

X Shaly siltstone ......................... 0 1-1/2

COAL ..................................... 0 9

X Coaly claystone ............................ 0 1

X COAL ................................... 0 1

X Shaly coal claystone .................... 0 3

COAL ....... .. .. .. . . ... .. .. . .. . . . . . . . .. . 1 0

X Gray claystone .......................... 5 +

Bed thickness ........................... 4 3-1/2

Coal thickness ........ ................ 3 9

Members marked (X) excluded from sample.

Analysis C-61955, as-received, follows:

Percent

Moisture ................................ 24.2

Volatile matter .......................... 34.9

Fixed carbon ............................ 33.1

Ash ........................................ 7.8

Sulfur .................... .............. . .3

B.t.u. .................................. 8,490

Continuing up Bidarki Creek from the top of the coast cliff, two 4-foot

coal beds were observed - one, one-fourth of the distance from the mouth to

the source, and the second, three-fourths of the distance from the mouth to

the source. Numerous other coal beds ranging from 6 inches to 3 feet in

thickness were observed. Occasionally, slide rock covered the outcrops. The

coal beds in Bidarki Creek did not cause high waterfalls, but distinct benches

were formed.

West of Bidarki Creek, above the Kachemak Bay coast, the bench land division is not distinct; however, in this area the outcrops of coal beds form

small benches and escarpments. Several large slide blocks were observed about

1 mile west of Bidarki Creek extending from Diamond Creek to the coast west of

Bluff Point. These slides have obscured the normal structure. A trail half a

mile in from the coast follows the strike of a 3-foot coal bed for a quarter

of a mile, and this probably is the limit of extent along Diamond Creek of the

slide area inland from the coast.

Above the head or source of Bidarki Creek, a 4-1/2-foot coal bed was observed near several homestead dwellings. A 4-1/2-foot bed of coal was measured

in the approximate center of the SE. 1/4 of sec. 12, T. 6 S., R. 14 W. This

3071 - 33 -
-1

R. I. 4520

bed was 4 feet near the center of the SW. 1/4 of sec. 12, T. 6 S., R. 14 W.

These two outcrops are half a mile apart and appear to be the same coal bed

with a general east-west strike and a north dip of 50 to 7°.

Farther north

R. 14 W., coal had

dip of 5° to 7° N.

and west, a little south of the center of sec. 3, T. 6 S.,

been mined from an outcrop with an east-west strike and a

The section follows (see fig. 8, loc. 3):

Description

Light-gray claystone .......................

Coaly claystone ...........................

Silty claystone ...........................

COAL ...................................

Coaly claystone and dirty coal (some lenses)

COAL .......................................

Gray claystone ............................

Thickness

Ft. In.

2 +

0 3

0 3

1 5

0 9

4 3

2 +

a

East of Bidarki Creek, and starting near the quarter corner on the south

side of the SE. 1/4 of sec. 16, T. 6 S., R. 13 W., a traverse was made up

Woodard's Creek from the end of the road to the C.A.A. radio station. Approximately 1,000 feet up the gulch from the end of the road a 3-1/2-foot coal bed

with a 2° dip to the north was measured. Two coal beds were found about half

a mile from the end of the road up the gulch; the first coal bed was 12 inches

to 18 inches in thickness and the second was 2 to 3 feet thick.

A 5-foot coal bed was observed about 1 mile up a gulch and approximately

1-1/2 miles from the village of Homer lying in approximately the center of

sec. 18, T. 6 S., R. 13 W., at an altitude of approximately 500 feet. Dips

of about 2 to the north were observed on an east-west strike. A waterfall

was formed by the 5-foot coal bed. Red ferruginous claystone was found 50

feet above the 5-foot coal bed. Four thin coal beds 8 to 18 inches thick,

about 12 feet apart, were found 80 feet above the 5-foot coal bed.

Two miles north of this area, near the center of sec. 5, T. 6 S., R. 13

W., a 2-foot bed of coal had been mined. Near the northeast corner of the SE.

1/4 of sec. 6, T. 6 S., R. 13 W., about 5 feet of coal had been mined. A measured section (see fig. 8, loc. 4) with a strike N. 45° E. and a 120 NW. dip is

as follows:

I

S

Description

Claystone (roof) ...........................

COAL ..................................

Claystone ................................

COAL ...... ............. ................

Claystone ................................

COAL . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . .

Claystone ..................................

COAL .......................................

Claystone ..................................

COAL .. . . . .. . . . . . . . .. . . . . . . . . . .. . . . .

Siltstone (floor) ........ ..................

- 34 -

Thickness

Ft. In.

1 +

0 7

2 8

1 1

0 3

0 10

1 0

0 2

0 6

2 3

1 +

3071

I -
R. I. 4520

A traverse down Bear Canyon, which is the longest and largest canyon to

the east, started at a 3-foot coal bed mined by Mr. Woodman in the NW. 1/4,

SE. 1/4, sec. 3, T. 6 S., R. 13 W., strike N. 50° E., dip 9° NW. (see fig. 8,

loc. 5). Many waterfalls are formed by coal beds. The upper part of the canyon comprises mostly sandy sediments. However, the sediments in the lower

part of the canyon are shaly. Twelve coal beds were observed below the first,

and these beds, in descending order, are: No. 1, 3 feet; No. 2, 3 feet; No. 3,

series of four thin beds; No. 4, 3 feet 9 inches; 1ob. 5, 4 feet; No. 6, 2 feet

(strike N. 70° E., dip 9° NW.); No. 7, 1 foot; No. 8, 2 feet 8 inches; No. 9,

1 foot 6 inches; No. 10, 1 foot 7 inches; No. 11, 5 feet 6 inches; No. 12, 1

foot coal, 1 foot clay, 1 foot coal.

The next gulch east, sometimes referred to as Waterman's, north of the

Charles Sharp property, begins in sec. 1, T. 6 S., R. 13 W., and extends to

the center of the SE. 1/4, sec. 36, T. 5 S., R. 13 W. One 3-foot coal bed,

one 3-1/2-foot coal bed, and 12 coal beds ranging from 6 inches to 2 feet in

thickness were observed. The strike of the 3-1/2-foot coal bed is N. 50° E.,

with a dip of 9° NW. The coal beds in the lower part of the canyon were covered

with slides and could not be measured. The covered areas probably contain coal

beds that are found in the adjacent canyons.

The farthest east canyon traversed began at the old Thurston Homestead in

the NW. 1/4, sec. 32 and SW. 1/4, sec. 29, T. 5 S., R. 12 W. Many thin beds

of coal and some reddish claystone were observed. The coal beds in the lower

half of the canyon appeared to be flat. The sediments in the upper half of the

canyon were sandy. A measured section of one bed is as follows:

a

Description

Claystone .................................

COAL .......................................

Claystone ................................

COAL .......................

Claystone ... ......... ...... .. ......

The following coal bed was measured at the mouth of

8, loc. 6):

Description

Claystone roof (concealed) ................

COAL ......................................

Claystone, somewhat coaly ..................

COAL .................. ...................

Claystone ..............................

COAL ......................................

Fine brown siltstone ......................

COAL ......................................

Gray claystone ............................

Thickness

Ft. In.

5 +

2 5

0 3

0 4

5 +

Fritz Creek (see fig.

Thickness

Ft. In.

0 10

0 3-1/2

0 3

0 4

0 3

0 2

0 4

0 6

Strike N. 70° E., dip 8° N.

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R. I. 4520

Homer Coal Corp. Mine

This mine is about 1-1/2 miles northwest of Homer, Alaska, on the shore

of Kachemak Bay, and access to it from Homer is over the Kenai Peninsula highway, which connects Kenai points and is projected to be built to Anchorage

around Turnagain Arm. The mine is 10 miles from the dock on Homer Spit, which

accommodates ocean-going vessels.

The present output is from development. The area was first opened in the

Cooper bed in about 1900, and the following abandoned openings were observed

in the vicinity of the Homer mine: Alsip slope, Alsip tunnel, English Company

shaft and tunnel, and Morgan shaft and dock site.

The extent of the underground workings in these abandoned openings is not

known. However, one of the entries of the Homer mine encountered old workings

at 32 feet inby the portal. It appears that the Homer mine is being developed

in an area that has been partly mined.

The present openings of the mine are two entries about 150 feet apart.

No. 1 entry had been advanced 30 feet and No. 2 entry 53 feet at the time of

this investigation.

These entries are driven on the apparent strike of the Cooper bed, which

is N. 70° E., dip 7° N. After the true strike of the bed is determined by the

entries, it is planned to drive a slope from the outby entry up the dip of the

bed to the surface.

The shore line at the mine is a perpendicular cliff 120 feet high, which

decreases in height east of the mine and increases to 200 feet in height

northwest of the mine. An inclined track has been built on the face of the

cliff, and from the base of the incline a track has been constructed on a

bench beneath the Cooper bed to the portals of No. 1 and No. 2 entries.

A section of the Cooper bed in the entry follows:

Thickness

Description Ft. In.

X Roof; claystone ....................... 0 9+

COAL .................................... 2 11

X Clay .................................... 0 1

COAL .................................... 1 10

X Clay ................................. 0 2

CQAL ..................................... 1 4

X Bottom, siltstone ....................... 0 6+

Bed thickness .......................... 6 5

Coal thickness .......................... 6 2

Members marked (X) excluded from sample.

3071 - 36 -
R. I. 4520

Analysis C-61783, as-received, follows:

e Percent

Moisture ................. ............... 5

Volatile matter ............................ 30.3

Fixed carbon ............................... 41.1

Ash ................. ..................... ... .. 12.1

Sulfur .................................... 4

B.t.u. .......... ... ................ .. 9,020

The Kenai coal formation contains several coal beds and openings and outcrops in these beds were observed in all of the north and south gulches that

extend into the upper bench land in the Homer area. The probable area extends

10 miles east and west and 3 miles north and south. Areas probably underlain

with coal are accessible to roads, but the Kenai coal formation has been identified for many miles. The minable reserve can be determined by an investigation by diamond drilling.

The local demand for coal in the Kenai Peninsula at this time is not large,

but this demand will increase as population grows. The dock at Homer is free

of ice in winter, and coal could be shipped by boat to Seward and then by rail

to Anchorage, as Cook Inlet is ice-bound between Homer and Anchorage in winter.

However, water shipment is possible to Anchorage from April 15 to November 15.

A cement plant may be constructed at Seldovia, which is across Kachemak Bay

from Homer. The source of fuel for this plant would be in the Homer area.

The reconnaissance in the vicinity of Homer indicated physical conditions

favorable for a modern mechanized mine. The extent of minable reserves and

characteristics of the bed must be known before the investment necessary to

plan and develop such a mine can be made. These conditions can be determined

only by an investigation by diamond drilling. The present demand does not

warrant such an investigation, but the time required for the work is considerable, and a diamond-drilling program should be started on the Eenai Peninsula

within the next 3 years.

The Kenai coal formation extends north of Homer, and coal is found on

Kenai Peninsula in the vicinity of Ninilchik, Happy Valley, Kasilof, and Kenai.

The coal has been used locally as a source of fuel, but the extent of the

deposits is not known. The same coal formation appears to cross Cook Inlet to

Tyonek and has been reported in the vicinity of Anchorage, Eagle River, Little

Susitna River at Wasilla and Houston, and on the tributaries of the Big Susitna

River near the Yentna River. Glacial debris and muskeg swamps cover parts of

these areas, and the beds have not been traced consistently, but several intermittent productive areas have been active in the past. It is anticipated that

further development may be expected from any or all of these areas in the

future. Lack of relief and elevation has made some of the areas susceptible

to water-flooding and surface seepage. Most of this coal is subbituminous.

Time would not permit investigation of these areas during this reconnaissance.

3071 - 37 -