EC. 313

GEOLOGICAL SURVEY CIRCULAR 313

RECONNAISSANCE FOR URANIUM-BEARING 

CARBONACEOUS ROCKS IN CALIFORNIA 

AND ADJACENT PARTS OF OREGON AND 

NEVADA

This report concerns work done on 

behalf of the U. S. Atomic Energy 

Commission and is published with 

the permission of the Commission.
UNITED STATES DEPARTMENT OF THE INTERIOR 

Douglas McKay, Secretary

GEOLOGICAL SURVEY 

W. E. Wrather, Director

GEOLOGICAL SURVEY CIRCULAR 313

RECONNAISSANCE FOR URANIUM-BEARING CARBONACEOUS ROCKS 

IN CALIFORNIA AND ADJACENT PARTS OF OREGON AND NEVADA

By George W. Moore and James G. Stephens

This report concerns work done on 

behalf of the U. 8. Atomic Energy 

Commission and is published with 

the permission of the Commission.

Washington, D. C.1K4

Free on application to the Geological Survey. Washington 25, D. C.
RECONNAISSANCE FOR URANIUM-BEARING CARBONACEOUS ROCKS 

IN CALIFORNIA AND ADJACENT PARTS OF OREGON AND NEVADA

By George W. Moore and James G. Stephens

CONTENTS

Abstract ......

Introduction ..,

California

Northern, 

Central ., 

Southern ,

Page1

1

2

2

2

5

Southwestern Oregon 

Western Nevada 

Petroliferous rocks . 

Literature cited 

Unpublished

reports ..........

Page

5

5

7

ILLUSTRATIONS

Page

Figure 1. Localities examined for uranium-bearing carbonaceous rocks in California and parts

of Oregon and Nevada, 1952 ............................................................ . 3

2. Diagrammatic section through the lone lignite field, Amador County, Calif. ..................... 4

TABLES

Page

Table 1. Analysis of samples collected in northern California .......................................... 2

2. Analysis of samples collected in central California............................................ 6

3. Analysis of samples collected in southern California. ......................................... 6

4. Analysis of samples collected in southwestern Oregon......................................... 7

5. Analysis of samples collected in western Nevada...... . ...................................... 7

6. Analysis of samples of petroliferous rocks collected in California .............................. 7

ABSTRACT

During the summer of 1952 a reconnaissance was 

conducted in California and parts of Oregon and Nevada 

in search of new deposits of uranium-bearing carbonaceous rocks. The principal localities found in California 

where uranium occurs in coal are listed here with, the 

uranium content of the coal: Newhall prospect, 

Los Angeles County, 0.020 percent; Fireflex mine, 

San Benito County, 0.005 percent; American lignite 

mine, Amador County, 0.004 percent; and Tesla prospect, Alameda County, 0.003 percent. An oil-saturated 

sandstone near Edna, San Luis Obispo County, contains 

0.002 percent uranium.

INTRODUCTION

As part of a program to discover new reserves 

of uranium in coal and other carbonaceous materials,

an investigation by the U. S. Geological Survey, on 

behalf of the Division of Raw Materials of the 

U. S. Atomic Energy Commission, was made during 

the summer of 1952 in California, western Nevada, 

and southwestern Oregon.

Although several occurrences of uranium associated with coal in the United States have been known for 

many years (Berthoud, 1875), only recently have they 

been considered more than geologic curiosities. Reconnaissance during the past 3 years has resulted in the 

discovery of large tonnages of coal containing small 

quantities of uranium (Denson and others, 1952). Coal 

having 0,1 percent uranium or more in the ash is now 

known in North and South Dakota, Wyoming, Idaho, 

Nevada, Montana, Colorado, and New Mexico.

Detailed studies of uranium-bearing lignite in 

the Dakotas were made by Denson, Bachman, and 

Zeller (1950). They indicate that the uranium is
secondary, being introduced by downward percolating meteoric water that has passed through overlying 

tuffaceous rocks in the White River and Arikaree formations. Rhyolites contain relatively large amounts of 

uranium (Evans and Goodman, 1941), and their tuffaceous equivalents seem to be particularly capable of 

releasing this uranium to solution. Spring water issuing from these rocks contains from 30 to about 80 parts 

per billion uranium many times the content of most 

natural waters (Aberdeen and others, 1952). By 

searching for beds of coal overlain by rocks of volcanic 

origin and rhyolitic composition, low-grade deposits 

of uranium have been found (Hail and Gill, 1953; Love, 

1952; Vine and Moore, 1952; Vine and others, 1953).

During the present investigation coals were 

systematically sampled throughout the area with 

special attention given to those deposits that are, or 

were, overlain by rocks of volcanic origin and rhyolitic 

composition. A total of 63 samples of carbonaceous 

rocks was taken for analysis from 38 localities (fig. 1). 

Results of the analysis are listed in tables 1-6.

Acknowledgments are given to the California 

Division of Mines and particularly to Gordon B. Oakeshott 

for valuable suggestions.

CALIFORNIA

Coal was investigated in 21 counties at most of 

the localities where it is reported in the literature or 

is listed in the files of the California Division of Mines. 

It ranges in age from Paleocene to Pliocene; and in 

rank, from high-volatile bituminous coal to partly 

coalified wood. The majority of the deposits, however, 

are of lignite or subbituminous coal. The coal crops 

out in widely scattered areas of relatively small extent. 

Resources, therefore, are small. They have been 

estimated at 100 million tons; and the total production 

through 1946 was 5, 270, 218 tons, valued at $23, 400, 260 

(Averill and others, 1948).

NORTHERN CALIFORNIA

Significant radioactivity was not detected at any 

of the localities visited in northern California. Coal 

of Eocene age was examined at two localities in the 

Umpqua(?) formation at the south end of the Rogue River 

field, Siskiyou County; and at five localities in Trinity and 

Humboldt Counties. Coal and lignite of Miocene age 

were sampled in the Covello area, Mendocino County, 

and in two formations of Pliocene age at the Maple Creek

and Garberville areas in Humboldt County. Carbonaceous shale was examined at two localities in 

Modoc County and one locality in Lake County. The 

results of the analysis are listed in table 1.

CENTRAL CALIFORNIA

The lone lignite field, Amador County, is in the 

foothills of the Sierra Nevada. It is in the lone formation of Eocene age in a northwest trending syncline. 

The only two coal mines in operation in the State at 

the time of the investigation are located here, producing montan wax and other industrial chemicals. The 

wax is used in the manufacture of polishes, carbon 

paper, and similar products.

The greatest radioactivity was found at the strip 

mine of the American Lignite Co. in sec. 26, T. 6 N., 

R. 9 E. (locality 35) about 1 mile southwest of lone. A 

maximum uranium content of 0.004 percent was found in 

the upper 9 inches of the 12-foot lignite zone (fig. 2). 

The uranium may have been derived from the overlying 

Valley Springs formation of Miocene( ?) age, and concentrated in the lignite by downward and laterally 

percolating solutions. The Valley Springs formation 

is composed largely of ash of rhyolitic composition, 

and the formation laps unconformably across the older 

rocks. Greater mineralization might be found under 

more favorable structural and stratigraphic conditions 

than exist at the American lignite mine, such as on the 

west flank of the field where erosion remnants of the 

Valley Springs formation directly overlap the coal beds. 

Bates (1945) shows that this stratigraphic relationship exists in the Edwin clay mine about 4 miles 

west of lone. At this locality, however, the 

lignite could not be examined because the mine 

workings were caved and inaccessible.

Samples were collected from the Humacid 

mine (locality 36), about 6 miles south of lone, 

where underground operations are also producing 

lignite for montan wax. This lignite has 0.002 percent equivalent uranium or less. Dumps from 

other caved coal mines in the vicinity were tested 

with the Geiger counter, but the radioactivity was 

not above background.

The rocks in the lone field are poorly exposed. 

Several coal beds are known to be present, and it is 

possible that the beds currently being mined are not 

the stratigraphically highest ones those most likely 

to be mineralized by downward percolating solutions. 

Therefore, the lone field merits additional investigation.

Table 1. Analysis of samples collected in northern California

Map 

locality

15

16

17

20

23

24

Laboratory 

no.

87689

87670

87692

87691

87693

87694

Thickness 

of unit 

( inches)

12

1

3

12

12

12

Equivalent 

uranium 

( percent)

0.001

U)

(')

U)

.002

.001

Uranium 

(percent)

 

 

___

(')

(0

Uranium 

in ash 

(percent)

...

 

 

0.001 (a)

Ash 

(percent)

58.6

78.9

11.1

13-7

48.6

15-8

Location 1 

(sec., T., R., Mer.)

15-38N-1E-MDM.

32-33N-1W-MEM.

6-33N-12W-MEM.

32-32N-9W-MDM.

3-5S-4E-HM.

2-21N-13W-MEM.

1 "MDM' indicates Mt. Diablo meridian; "HM", Humboldt meridian. 

Equivalent uranium- or uranium content of less than 0.001 percent.
LOCALITIES EXAMINED 

OREGON

Coot Bay field

1. South Slough mine 

Z. Southport prospect 

3. Scorby-McGinity mine

Melrose area

Eden Ridge field

5. Carter proipect 

Rogue River field

6. Medford mine

7. Phoenix mine

8. Aihland mine

CALIFORNIA

Rogue River field 

9. Ager mine

10. Yreka prospect 

Modoc area

11. Stone Coal prospect 

1Z. Pit prospect 

Humboldt area

13. Hoopa prospect

14. Maple Creek prospect 

Kosk Creek area

15. Kosk Creek prospect

16. Coal Creek prospect 

Trinity area

17. Big Bar prospect

18. Hay Fork prospect

19. Hyampom prospect

ZO. Reeee Brothers mine 

Oak Run area

Zl. Bar nee Ridge mine

ZZ. Coal Creek prospect 

Garberville area

Z3. Rancheria Creek prospect 

Covello area

Z4. Doe Rios mine 

Oroville area

25. Oroville prospect 

Lake area

Z6. Lakeport prospect 

Sutter Butte» area

27. North Butte prospect

28. South Butte prospect 

Lincoln area

Z9. Lincoln Clay Co. mine

30. Cladding-McBean mine 

Sonoma area

31. Pierson prospect

32. Kawana Springs prospect 

Solano arta

33. American Canon prospect

Reno area

59. Verdi proepect 

Yerington area

60. Lewis mine

lone field

34. Harvey mine

35. American Lignite mine

36. Humacid mine 

Mount Diablo field

37. Nortonville mine

38. Sommersville, Stewartville,

Star, and Tetonia mines 

Corral Hollow field

39. Tesla proepect

40. Mitchell Ravine prospect 

Santa Cruz area

41. Santa Cruz mine 

4Z. Aptos prospect 

Stone Canyon field

43. Tres Pinos prospect

44. Pinnacles prospect

45. Fireflex (Monterey) mine

46. Oat Canyon prospect

47. Priest Valley prospect

48. Coalinga mine

49. Stone Canyon mine 

San Lnis Obispo area

50. See Canyon seep

51. Edna mine 

McKittrick area

52. McKittrick prospect 

Mohave Desert area

53. Gerbracht Camp prospect 

Los Angeles area

54. Newhall prospect 

Santa Ana Mountains area

55. Santiago mine

56. Alberhill mine 

San Diego area

57. Del Mar prospect

58. La Jolla prospect

Coaldale field

61. KoontK mine

62. Number 1 shaft

EXPLANATION

Coal or carbonaceous shale sample

Coal or carbonaceous ehale tested in the 

field for radioactivity

+ 51 

Petroliferous rock sample

Figure 1. Localities examined for uranium-bearing carbonaceous rocks in California and parts of Oregon and

Nevada, 1952.
Volcanic ash (Valley Springs

Section in the 

American lignite mine

V-Volley Springs fm. (Mloetat)

lane fm. (Eocint)

Greenstone (prf-Crttac*oui) -» 

2 Miles

Scale 

Vertical scale twice horizontal scale

From data by Piper,and others, 1939

Figure 2. Diagrammatic section through the lone lignite field, Amador County, California.

4
Thin beds of lignitic shale were sampled in two 

clay mines about 30 miles north of the lone field, near 

Lincoln, in Placer County. The lignitic shale from the 

Atkinson pit of the Gladding-McBean mine (locality 30) 

contains 0. 002 percent equivalent uranium, and the 

gray clay directly overlying the lignitic shale contains 

0.001 percent equivalent uranium. Two core samples 

of impure lignite from depths of 61 and 67 feet at the 

Lincoln Clay Co. mine (locality 29) have 0.001 percent 

or less equivalent uranium.

At Sutter Buttes, Butte County, Eocene rocks are 

exposed along the flanks of an eroded volcano; from them 

coal has been mined for local use at several 

localities. A bed of impure coal, 1 inch thick, 

from sec. 30, T. 16 N., R. 2 E. (locality 28), contains 0.001 percent uranium. A sample of andesite 

porphyry from the volcanic plug has 0.001 percent 

equivalent uranium. Lignite north of Oroville (locality 

25) in Butte County contains less than 0.001 percent.

Lignite of Pliocene age, interbedded with the 

andesitic Sonoma volcanic s, was sampled north of 

Santa Rosa (locality 31), Sonoma County. It contains 

less than 0.001 percent uranium. Several localities 

were tested south of Santa Rosa, but radioactivity was 

not detected.

In American Canon, Solano County, a 6-inch bed 

of lignite in the Domengine sandstone of Eocene age 

contains 0.002 percent uranium. This bed crops out 

in the NW| sec. 14, T. 4 N., R. 3 W. (locality 33). 

South of this locality, in Contra Costa County, is the 

Mount Diablo coal field, which, because of its proximity 

to the San Francisco market, has produced most of the 

coal in the State. A total of about 3 million tons has 

been mined, but during the past 50 years the mines have 

been inactive. Many localities in this field were tested 

for radioactivity but none was detected. The analyses 

of samples taken, however, show that small quantities 

of uranium are present in some of the beds. At 

Nortonville (locality 37) the uranium content of a 1-foot 

channel sample from the top of a 3-foot bed is 0.001 percent, but because the ash content is only 8.35 percent, 

the concentration of uranium in the ash is 0.007 percent.

South of the Mount Diablo field is the Corral Hollow 

field in Alameda County. Many coal localities in the 

Tesla formation of middle Eocene age were tested and 

found to be nonradioactive. The most highly uraniferous 

coal in the area is a 10-inch bed that crops out in a road 

cut in the NWi sec. 25, T. 3 S,, R. 3 E. (locality 39); 

it contains 0.003 percent uranium.

About 2 miles south of Aptos (locality 42) in 

Santa Cruz County, a 1-foot bed of lignite in the beach 

cliffs has 0.001 percent uranium, 49.6 percent ash, 

and 0.003 percent uranium in the ash.

Coal and carbonaceous shale were tested at many 

localities in the Stone Canyon coalfield and nearby areas 

in San Benito, Fresno, and Monterey Counties, but only 

one bed has a significant concentration of uranium. This 

bed, 6 inches thick, is located 9 feet stratigraphically 

above the main 5-foot bed at the Fireflex (Monterey) 

mine (locality 45) in Monterey County. It contains 

0.005 percent uranium, 25.1 percent ash, and 0.021 percent uranium in the ash. The main bed contains less than 

0.001 percent equivalent uranium. Results of the analysis 

of samples from c entral California are shown in table 2.

SOUTHERN CALIFORNIA

In southern California only one bed of 

carbonaceous material was found that contains a 

significant quantity of uranium. This is a bed 

of lignite in the Saugus formation of Pliocene and 

Pleistocene age, cropping out about 1 mile southwest of Newhall (locality 54), Los Angeles County, 

in the NW| sec. 9, T. 3 N., R. 16 W. The 6-inch 

bed contains 0.020 percent uranium, the greatest 

concentration of uranium found in coal in this 

investigation. The lignite contains 37.7 percent 

ash and 0.054 percent uranium in the ash. Coal 

is not common in the Saugus formation, however, 

and it is not likely that beds of minable thickness 

will be found.

Coal was examined in the Goler formation 

(Dibblee, 1952) 1 mile northwest of Gerbracht Camp 

(locality 53) in Kern County, and was found to 

contain less than 0.001 percent uranium.

In the Santa Ana Mountains area in Orange 

and Riverside Counties, the most radioactive coal 

that was sampled was from the Santiago mine 

(locality 55) on the east shore of Irvine Lake, 

8 miles east of Orange, Orange County. It contains 0.001 percent uranium, 28.4 percent ash, 

and 0.005 percent uranium in the ash. Other 

samples from this area, and from the Alberhill 

mine (locality 56) in the SEi sec. 22, T. 5 S., 

R. 5 W., near Elsinore, Riverside County, contain less than 0.001 percent equivalent uranium.

Lignite at Del Mar (locality 57), San Diego County, 

in sec. 11, T. 14 S., R. 4 W., is nonradioactive. 

One mile northeast of La Jolla small pods of 

coallike material were collected from a marine 

formation of Late Cretaceous age (locality 58). 

This material has less than 0.001 percent equivalent uranium. Table 3 shows the results of the 

analysis of samples collected in southern California.

SOUTHWESTERN OREGON

Coal was tested for radioactivity and sampled 

for uranium in the Coos Bay, Eden Ridge, and 

Rogue River fields in Coos, Douglas, and 

Jackson Counties of southwestern Oregon. Many 

localities were examined in the Coos Bay field, 

where large reserves of subbituminous coal in 

the Coaledo formation of Eocene age are present 

(Duncan, 1953a), but significant radioactivity was 

not found. In the Eden Ridge field, coal was 

examined in the Carter and Anderson beds, as 

well as in thinner unnamed beds. Radioactivity 

was not detected here, either; or to the north in 

the Melrose area; or to the south in the Rogue River 

field, where coal has been mined from the Umpqua( ?) 

formation of Eocene age. Results of the analysis 

of samples from southwestern Oregon are shown 

in table 4.

WESTERN NEVADA

Near Verdi (locality 59), Washoe County, a sample of lignite was collected from the Truckee formation 

of Tertiary age in the SEi sec. 4, T. 19 N., R. 18 E.
Table 2. Analysis of samples collected in central California

Map 

locality

25

28

29A

29B

30

31

33

35A

35B

35C

35D

35E

36A

36B

36C

36D

37A

37B

37C

37D

37E

39

40A

40B

42

45A

45B

46

47

48A

48B

Laboratory 

no.

87696

87695

90226

90227

90225

90246

90237

90228

90229

90230

90231

90232

90233

90234

90235

90236

90238

90239

90240

90241

90242

90245

90243

90244

95500

95504

95505

95503

95502

95508

95509

Thickness 

of unit 

(inches)

12

1

36

6

12

12

6

9

9

18

24

24

6

12

24

24

12

12

12

24

12

10

12

12

6

12

12

6

18

Equivalent 

uranium 

(percent)

0.001

.002

.001

(2)

.002

(*)

.001

.004

.002

.002

(2)

(*)

.002

.001

.001

.001

.001

(2)

(0

.001

.002

.004

.001

(2)

.002

.006

(2)

.001 (»)

(«)

.001

Uranium 

(percent)

(2)

0.001

 

 

 -

 

.002

.004

.002

.002

(2)

(2)

.001

(2)

.001

.001

 

 

.001

.001

.003

.001

 

.001

.005

 

(2)

 (2)

Uranium 

in ash 

(percent)

0.001

.001

 

 

 

 

.004

.007

.002

.005

.003

.002

 

.004

.002

.004

.007

 

 

.003

.002

.006

.002

 

.003

.021

 

(2)

 

.001

Ash 

(percent)

39.4

77-2

63.6

62.9

 

80.6

38.5

59.8

75.6

3^.6

13.3

16.2

26.9

6.68

19-6

8.35

6.77

6.04

39.6

71.2

54.4

50.5

19.0

49.6

25.1

61.2

 _

18.2

Location 1 

(sec., T., R.)

11-20N-3E.

30-16N-2E.

9-12N-6E.

Do.

16-12N-6E.

27-8N-8W.

14-4N-3W.

26-6N-9E.

Do.

.Do.

Do.

Do.

29-5N-10E.

Do.

Do.

Do.

5-1N-1E.

Do.

Do.

Do.

Do.

25-3S-3E.

30-3S-4E .

Do.

2 miles south of

Aptos .

21-17S-10E.

Do.

20-19S-11E.

21-20S-12E.

27-20S-14E.

Do.

1 A11 townships are based on the Mt. Diablo meridian. 

2Equivalent uranium or uranium content of less than 0.001 percent.

Table 3. Analysis of samples collected in southern California

Map 

locality

53A

53B

54A

54B

55A

55B

56A

56B

56C

56D

56E

56P

58

Laboratory 

no.

95506

95507

95519

95520

95517

95518

95511

95512

95513

95514

95515

95516

95521

Thickness 

of unit 

( inches)

12

6

6

6

12

12

12

12

12

Equivalent 

uranium 

(percent)

(2) ' 0

(2

(2

(*

(2

(,«

(2

(*

.001

003

.011

.002

(*)

Uranium 

(percent)

(«>"""

0.020

.001

. - 

 _

___

___

___

_ _

_ _ _

 

Uranium 

in ash 

(percent)

...

0.001

 

.054

.005

 

- 

___

_ _

_ _ .

___

 

 

Ash 

(percent)

 

49.7

 

37.7

28.4

 

___

___

_ _

_ _

 

 

Location i 

(sec., T., R.)

Gerbracht Camp.

Do.

9-3N-16W-SBM.

Do.

8 miles east of

Orange .

Do.

22-5S-5W-SBM.

Do.

Do.

Do.

Do.

Do.

1 mile northeast of

La Jolla.

1 "SBM" indicates San Bernardino meridian.

2 Equivalent uranium or uranium content of less than 0.001 percent.
The lignite has less than 0.001 percent equivalent 

uranium. Other nearby lignite beds and plant compressions are not radioactive. Samples of coal in 

sec. 36, T. 8 N., R. 27 E., from the Lewis mine 

(locality 60), Lyon County, contain less than 

0.001 percent equivalent uranium. Younger lignites 

in this vicinity are also nonradioactive. Samples 

were collected from the Esmeralda formation in the 

Coaldale field, Esmeralda County. Here, as much 

as 1.86 percent uranium is known to occur in 

a tuff of rhyolitic composition (Duncan, 1953b). 

The minerals autunite and phosphuranylite have 

been identified in the tuff. In sec. 33, T. 2 N., 

R. 38 E., coal coUected near a fault (locality 62) 

which brings the tuff in contact with the coalbearing rocks, has 0.003 percent equivalent 

uranium. A sample of carbonaceous shale from 

sec. 28, T. 2 N., R. 37 E. (locality 61) also 

has 0.003 percent equivalent uranium, while coal 

underlying this shale has only 0.001 percent uranium.

Table 5 shows the results of the analysis of samples 

collected in western Nevada.

PETROLIFEROUS ROCKS

Oil-saturated sandstone containing about 10 percent 

oil and 0.002 percent uranium was sampled in a quarry 

for road metal about 1 mile south of Edna (locality 51), 

in San Luis Obispo County. If all the uranium is present 

in the oil, and the oil could be leached from the rock, it 

would contain 0.02 percent uranium. Ashing of the . 

leached oil would permit further concentration of the 

uranium. Oil-saturated sandstone was also examined 

near Santa Cruz (locality 41),Santa Cruz County, and near 

McKittrick (locality 52),Kern County. Both contain 

0.001 percent, or less, equivalent uranium. Asphaltite 

in See Canyon (locality 50), San Luis Obispo County, 

has 0.001 percent uranium in the ash and 18.9 percent ash. 

The analysis of petroliferous rocks is shown in table 6.

Table 4. Analysis of samples collected in southwestern Oregon

Map 

locality

1

2

5

Laboratory 

no.

87700

87698

87697

Thickness 

of unit 

(inches)

12

12

6

Equivalent 

uranium 

(percent)

( 2 )

0.001

.001

Uranium 

(percent)

 

Uranium 

in ash 

(percent)

~~_

- 

Ash 

(percent)

8.4

59-5

60.7

Location 1 

(sec., T., R.)

2-26S-14W-WM.

14-26S-13W-WM.

32-32S-11W-WM.

1 "WM" indicates Willamette meridian.

Equivalent uranium content of less than 0.001 percent.

Table 5. Analysis of samples collected in western Nevada

Map 

locality

59

60A

60B

6lA

61B

62

Laboratory 

no.

90247

90248

90249

90252

90251

90250

Thickness 

of unit 

(inches)

12

12

12

12

12

12

Equivalent 

uranium 

(percent)

(»)

(0

(2)

0.005

.001

.003

Uranium 

(percent)

_ _

~~~

__

0.001

Uranium 

in ash 

(percent)

 

___

 

0.001

Ash 

(percent)

30.0

31.4

38.6

 

50.0

68.4

Location L 

(sec., T., R.)

4-19N-18E-MDM.

36-8N-27E-MDM.

Do.

28-2N-37E-MDM.

Do.

33-2K-37E-MDM.

1 "MDM" indicates Mt. Diablo meridian.

2 Equivalent uranium content of less than 0.001 percent.

Table 6. Analysis of samples of petroliferous rocks collected in California

Map 

locality

41

50

51

52

Laboratory 

no.

95501

95523

95522

95510

Equivalent 

uranium 

(percent)

0.001

(2)

.002

(2)

Uranium 

(percent)

__ _

(2)

0.002

 

Uranium 

in ash 

(percent)

__ _

0.001

.002

 

Ash . 

(percent)

 

18.9

89.7

Location x 

( sec . , T . , R . , Mer . )

4 miles west of

Santa Cruz.

20-31S-12E-MDM.

1 mile south of Edna.

29-30S-22E-MDM.

lmMDM" indicates Mt. Diablo meridian.

2 Equivalent uranium or uranium content of leas than 0.001 percent.
LITERATURE CITED

Averill, C. V., King, C. R., Symons, H. H., and 

Davis, F. F., 1948, California mineral production 

for 1946: Calif. Div. of Mines Bull. 139, p. 13-14.

Bates, T. F., 1945, Origin of the Edwin clay, lone, 

California: Geol. Soc. America Bull. 56, p. 1-38.

Berthoud, E. L., 1875, On the occurrence of uranium, 

silver, iron, in the Tertiary formations of Colorado 

Territory: Acad. Nat. Sci. Philadelphia Proc., 

v. 27, p. 363-365.

Dibblee, T. W., Jr., 1952, Geology of the Saltdale quadrangle, California: Calif. Div. of Mines Bull. 160, p. 19.

Duncan, D. C., 1953a, Geology and coal deposits 

in part of Coos Bay coal field, Oregon: U. S. Geol. 

Survey Bull. 982-B, p. 1-72.

Duncan, D. C., 1953b, A uranium-bearing rhyolitic 

tuff deposit near Coaldale, Esmeralda County, Nev.: 

U. S. Geol. Survey Circ. 291.

Evans, R. D., and Goodman, Clark, 1941, Radioactivity 

of rocks: Geol. Soc. America Bull. 52, p. 475.

Love, J. D., 1952, Preliminary report on uranium 

deposits in the Pumpkin Buttes area, Powder River 

Basin, Wyoming: U. S. Geol. Survey Circ. 176.

Piper, A. M., Gale, H. S., Thomas, H. E., and 

Robinson, T. W., 1939, Geology and grpundwater 

hydrology of the Mokelumne area, California: 

U. S. Geol. Survey Water-Supply Paper 780.

Vine, J. D., and Moore, G. W., 1952, Uraniumbearing coal and carbonaceous rocks in the Fall Creek 

area, Bonneville County, Idaho: U. S. Geol. Survey 

Circ. 212.

UNPUBLISHED REPORTS

Aberdeen, E. J., and others, 1952, Interim report 

on the location of nonsaline uraniferous waters: 

U. S. Geol. Survey Trace Elements Memo. Rept. 281.

Denson, N. M., Bachman, G. O., and Zeller, H. D., 

1950, Summary of new information on uraniferous 

lignites in the Dakotas: U. S. Geol. Survey Trace 

Elements Memo. Rept. 175.

Denson, N. M., and others, 1952, Summary of uraniumbearing coal, lignite, and carbonaceous shale investigations in the Rocky Mountain region during 1951: 

U. S. Geol. Survey Trace Elements Memo Rept. 341.

Hail, W. J., Jr., and Gill, J. R., 1953, Radioactive 

carbonaceous shale and lignite deposits in the 

Goose Creek district, Cassia County, Idaho: 

U. S. Geol. Survey Trace Elements Inv. Rept. 272.

Vine, J. D., Bachman, G. O., Read, C. B., and 

Moore, G. W., 1953, Uranium-bearing coal and 

carbonaceous shale in the La Ventana area, Sandoval 

County, N. Mex.: U. S. Geol. Survey Trace Elements 

Inv. Rept. 241.

1ST.-OOP. SEC.. MSH.. D.C.S3li»3