Selected Annotated Bibliography 

of the Geology and Occurrence 

of Uranium-Bearing Marine 

Black Shales in the United States

GEOLOGICAL SURVEY BULLETIN 1059-F

This compilation was done on behalf of 

the U. S. Atomic Energy Commission 

and is published with the permission of 

the Commission \

Selected Annotated Bibliography 

of the Geology and Occurrence 

of Uranium-Bearing Marine 

Black Shales in the United States

By CAROLYN E. FIX

SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

GEOLOGICAL SURVEY BULLETIN 1059-F

This compilation was done on behalf of 

the U. S. Atomic Energy Commission 

and is published with the permission of 

the Commission

UNITED STATES GOVERNMENT PRINTING-OFFICE, WASHINGTON : 1958
UNITED STATES DEPARTMENT OF THE INTERIOR 

FRED A. SEATON, Secretary

GEOLOGICAL SURVEY 

Thomas B. Nolan, Director

Fix, Carolyn Elizabeth, 1922-

Selected annotated bibliography of the geology and occurrence of uranium-bearing marine black shales in the United 

States. Washington, U. S. Govt. Print. Off., 1958.

iii, 263-325 p. plate (in pocket) 23 cm. (U. S. Geological Survey. Bulletin 105&-F. Selected bibliographies of uranium geology)

1. Uranium ores U. S. Bibl. (Series: U. S. Geological Survey. Bulletin 1059-F. Series: U. S. Geological Survey. Selected 

bibliographies of uranium geology)

016.55349

For sale by the Superintendent of Documents, U. S. Government Printing OfiBce 

Washington 25, D. C. - Price 25 cents (paper cover)
CONTENTS

	Page 

Abstract_______________________________________ 263

Introduction. ___________________________________________________ 263

Explanation of the bibliography___________________________________ 264

Bibliographies of uranium_____________________________-____________ 265

Annotated bibliography.___________________________________________ 266

Indexes.-___________________________________ 319

Authors..___________________________________ 319

Geographic areas.___________________________________________ 320

Stratigraphic units_____________________-_--_-____-_______ 322

Subjects___________________________________ 324

ILLUSTRATION

PLATE 3. Map of occurrences of uranium-bearing marine black shales in 

the United States; uranium content and key to references. _ _In pocket

m

SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

SELECTED ANNOTATED BIBLIOGRAPHY OF THE GEOLOGY AND OCCURRENCE OF URANIUM-BEARING 

MARINE BLACK SHALES IN THE UNITED STATES

By CAROLYN E. Fix

ABSTRACT

This bibliography consists of 81 annotated references concerned with the 

geology and occurrence of uranium in marine black shales. The annotations, 

arranged alphabetically by author, present information on geology, geographic 

distribution, environment of deposition, mode of occurrence, and analytical data. 

A map shows the distribution and uranium content of uraniferous shales in 

the United States including Alaska.

The data in the annotations are indexed according to author, geographic area, 

stratigraphic units, and subject.

INTRODUCTION

Uranium was first discovered in marine black shales in 1893 by 

Nbrdenskiold 1 in samples of alum shale of Late Cambrian age in 

southern Sweden. In 1909 this shale was mined for radium (Nininger, 

1954, p. 76), and in 1948 uranium was being recovered from this 

shale.2 In recent years this shale also has been mined and processed 

for oil.

Since the first discovery was made, uranium has been found in many 

black shales in many parts of the world. In the United States 

numerous marine black shales, chiefly of Paleozoic age, have been examined in the recent search for uranium deposits. Although many of 

these marine black shales contain slightly more uranium than marine 

sedimentary rocks in general, only a few of these units contain more 

than 0.005 percent uranium. Because of their wide areal distribution 

and uniform uranium content, marine black shales are considered to

1 Nordenskiold, A. E., 1893, R4marques sur le fer natif o'Ovifak et sur le bitumen des 

roches cristallines de Sufcde: Acad. sci. [Paris] Comptes rendus, v. 116, p. 677-678.

a Anonymous, 1953, Swedish uranium production : South African Mining and Eng. Jour., 

v. 64, no. 3146, p. 521.

263
264 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

represent vast but low-grade resources of uranium. None of these 

uraniferous shales, however, is of commercial significance at present.

Some of the domestic black shales have been studied in considerable 

detail to determine the distribution, and the geologic factors controlling the distribution, of their uranium. These include the Chattanooga shale of Devonian and Mississippian age in southeastern United 

States, the Woodford shale and its correlatives of Devonian and 

Mississippian age in Oklahoma and adjacent States, the Middle and 

Lower Pennsylvanian shales of Kansas and Oklahoma, the Cretaceous 

Eagle Ford shale of Texas, and the Sharon Springs member of the 

Pierre shale of Cretaceous age in South Dakota and Nebraska. Other 

black shales that have been examined include the Devonian Antrim 

shale of Michigan; shale in the Mississippian Salem limestone (formerly called Spergenlimestone) of Missouri; the subsurface Hartville 

formation of Mississippian (?), Pennsylvania, and Permian age in 

western Nebraska and eastern Wyoming; and black shale beds in the 

Pennsylvanian cyclothems of the Midcontinent and the Appalachian 

and Eastern Interior Basins.

In general, most of the uraniferous marine black shales have the 

following features in common: (a) They are relatively thin widespread deposits, probably representing extremely slow deposition 

over a long period of time; (b) they are carbonaceous, containing 

abundant plant matter; (c) sulfides and some phosphate are characteristically present; (d) they contain little or no calcium carbonate; 

and (e) almost all are Paleozoic or older in age.

Two main problems that have arisen during the investigations of 

uranium-bearing shales are the mineralogical association of the 

uranium and the mode of origin of the uranium. Intensive laboratory 

studies have been made, but no uranium-bearing minerals have been 

identified to date (195Y), and the physical separation of a fraction 

where the uranium is concentrated has been only partially successful. 

The uranium seems to be finely disseminated and is associated with 

the organic matter in some shales and possibly with the clay fraction 

in others.

All investigators seem to agree that the uranium was deposited at 

about the same time as the enclosing sediments in an organic- and 

sulfide-rich reducing environment, but the paleogeochemistry of precipitation and (or) adsorption of the uranium, and the relationship 

between paleogeographic conditions and uranium concentration are 

still in question.

EXPLANATION OF THE BIBLIOGRAPHY

The bibliography consists of annotations or abstracts of selected 

reports that pertain to the geology and occurrence of uranium in
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 265

marine black shales and their metamorphic equivalents in the United 

States. Only those reports that were available to the public before 

June 30,1956, are included. Most of the reports may be consulted in 

the larger public, university, or scientific libraries. A few reports that 

have been released to the public in open file may be consulted at designated offices of the Geological Survey.

An effort has been made to include only those references to shales 

whose uranium is believed to be of syngenetic origin and whose major 

source of radioactivity is uranium. Many general papers on the 

geology of uranium deposits refer to marine black shales, and some 

of these general papers have been included.

The ideas and opinions expressed in the annotations are those of the 

original authors. Material added in some annotations by the present 

author is enclosed in brackets. Where there are dual reference citations for quoted material, the quotation is taken from the first reference. The statements on the stratigraphic classification and nomenclature are those of the various authors and do not necessarily follow 

usage of the U. S. Geological Survey.

The annotations are arranged in alphabetical order by author and 

are numbered consecutively for indexing. Reports by the same author 

or authors are arranged first in chronological order and second in 

alphabetical order by title. The annotations are indexed by (a) 

author, (b) geographic area, (c) stratigraphic unit, and (d) subject.

This bibliography was prepared by the U. S. Geological Survey 

on behalf of the Division of Raw Materials, U. S. Atomic Energy Commission.

The index map (pi. 3) shows (a) the general location of marine 

black shales containing more than 0.001 percent uranium; (b) the 

uranium content based on chemical analysis, or, where indicated by subscript "e," equivalent uranium content; (c) one or more references for 

each location, indicated by numbers corresponding to the reference 

number in the bibliography.

BIBLIOGRAPHIES OF URANIUM

Additional references to uranium deposits are contained in the following general bibliographies: 

Alien, R. E., 1953, Uranium and its compounds, a bibliography of unclassified

literature: U. S. Atomic Energy Comm. TID-3041, issued by U. S. Atomic

Energy Comm. Tech. Inf. Service Ext., Oak Ridge, Tenn. 

Cooper, Margaret, 1951, Preliminary bibliography on uranium and thorium and

radioactive carbonaceous deposits: U. S. Atomic Energy Comm. RMO-835,

issued by U. S. Atomic Energy Comm. Tech. Inf. Service Ext., Oak Ridge,

Tenn. 

 1953, Selected bibliography on uranium exploration and the geology of

uranium deposits: U. S. Atomic Energy Comm. RME-4007, issued by U. S.

Atomic Energy Comm. Tech. Inf. Service Ext., Oak Ridge, Tenn.
266 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

Cooper, Margaret, 1953, Bibliography and index of literature on uranium and 

thorium and radioactive occurrences in the United States, Part 1, Arizona, 

Nevada, and New Mexico: Geol. Soc. America Bull., v. 64, p. 197-234.

 1953, Bibliography and index of literature on uranium and thorium and 

radioactive occurrences in the United States, Part 2, California, Idaho, 

Montana, Oregon, Washington, and Wyoming: Geol. Soc. America Bull., v. 

64, p. 1103--1172.

 1954, Bibliography and index of literature on uranium and thorium and 

radioactive occurrences in the United States, Part 3, Colorado and Utah: Geol. 

Soc. America Bull., v. 65, p. 467-590.

 1955, Bibliography and index of literature on uranium and thorium and

radioactive occurrences in the United States, Part 4, Arkansas, Iowa, Kansas,

Louisiana, Minnesota, Missouri, Nebraska, North Dakota, Oklahoma, South

Dakota, and Texas; Geol. Soc. America Bull., v. 66, p. 257-326. 

Croxton, F. E., 1951, Uranium and its compounds a bibliography of unclassified

literature: Oak Ridge, Tenn., Carbide & Carbon Chemicals Co., K-25 Plant,

Report K-295, Part 2. 

Postell, P. E., and Voress, H. E., 1953, Unclassified bibliographies of interest to

the atomic energy program: U. S. Atomic Energy Comm. TID-3043, issued

by U. S. Atomic Energy Comm. Tech. Inf. Service Ext., Oak Ridge, Tenn. 

Schwind, S. B., and Croxton, F. E., 1950, Radium. A bibliography of unclassified

literature: U. S. Atomic Energy Comm. TID-363, issued by U. S. Atomic

Energy Comm. Tech. Inf. Service Ext., Oak Ridge, Tenn. 

Wallace, J. H., and Smith, H. B., 1955, Bibliography of U. S. Geological Survey

trace elements and related reports to June 1, 1954: U. S. Geol. Survey Bull.

1019-B, p. 63-144.

ANNOTATED BIBLIOGRAPHY

1 Alexander, F. M., 1953, The Chattanooga black shale A possible future 

source of uranium: Tennessee Dept. Conserv., Div. Geology Inf. Circ. 

1, 3 p.; repr. from Tennessee Conservationist, June 1953.

This pamphlet presents information to the public on the Federal Government's investigations of the Chattanooga shale in southeastern United 

States as a possible future source of uranium. A general description of 

the lithologic character, thickness, distribution, and correlative formations of the Chattanooga shale is given.

In 1921 and 1922 the Tennessee Division of Geology sponsored an investigation of the oil potential of the kerogen-rich Chattanooga shale. It was 

found that as much as 10 to 15 gallons of oil per ton could be extracted from 

the shale, though this figure varied widely from place to place.

"The fact that marine black shales contain very small amounts of radioactive substances has been known to geologists for many years," but before 

the "atomic age" was ushered in, this knowledge was only of academic 

interest. The uranium content of the Chattanooga shale has been reported 

to range from 0.001 to 0.03 percent, but "much of the formation probably 

contains less than 0.2 pound of uranium per ton of shale." Studies indicate, however, that the marine black shales of eastern and central United 

States are promising as large potential uranium reserves.

Major problems to be solved before this widespread low-grade source 

of uranium can be economically exploited are the development of low-cost 

methods of mining the shale and extracting the uranium.
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 267

Bachman, G. O., and Read, C. B., 1952, Trace elements reconnaissance 

investigations in New Mexico and adjoining States in 1951: U. S. 

Geol. Survey TEM-443-A, 22 p., issued by U. S. Atomic Energy Comm. 

Tech. Inf. Service Ext., Oak Ridge, Tenn.

In 1951 a reconnaissance was made in New Mexico, Arizona, Colorado, 

and Utah for uranium in coal and carbonaceous shale, chiefly of Mesozoic 

age; and in marine black shale of Paleozoic age. "Tertiary volcanic 

rocks, considered to be a possible source for uranium in the coal and associated rocks, were examined where the volcanic rocks were near coalbearing strata." Except for a coal unit in the Mesaverde formation, on 

La Ventana Mesa, Sandoval County, N. Mex., which contains as much as 

0.62 percent uranium, all other coals and associated rocks tested contain 

0.01 percent or less uranium. The equivalent uranium content of tested 

marine black shales did not exceed 0.004 percent.

The results of the tests for uranium in the marine black shales are as 

follows:

Martin limestone (Devonian), Gila Count1}/, Ariz. Four samples from the 

upper shaly part contain from 0.003 to 0.004 percent equivalent uranium 

but less than 0.001 percent uranium in sample and in ash (90 percent 

average ash).

Percha shale (Upper Devonian), Otero County, N. Mex. Nine samples 

contain from 0.001 to 0.004 percent equivalent uranium; 2 of these samples 

were from a calcareous zone and contain 0.004 percent equivalent uranium 

and 0.002 percent uranium.

Lake Valley limestone (Mississippian), Socorro County, N. Mex. One 

sample of calcareous shale contains 0.002 percent equivalent uranium.

Madera formation (Pennsylvanian), Mora County, N. Mex. One sample 

of bituminous shale contains 0.002 percent equivalent uranium and 0.001 

percent uranium.

Bain, G. W., 1950, Geology of the fissionable materials: Bcon. Geology, 

v. 45, p. 273-323. See p. 284, 291-92, 308, and 311.

This report is a general summary of the geological associations, types of 

deposits, and world resources of uranium. Uranium deposits are classified as either (a) primary or hypogene, (b) sedimentary or bedded, and 

(c) oxidized bodies. Maps showing the locations of the principal uranium 

deposits of the world are included.

"The uraniferous bituminous source rocks for petroleum are marine 

deposits that accumulated very slowly. Generally only marine shales 

yielding over 10 percent of oil by distillation have significant uranium." 

However, a few slates and schists of shale derivation still retain their 

uranium, but they have been so metamorphosed as to lose most of their 

volatile hydrocarbons. "The uranium content of 0.02 percent U3O8 or 

more has been confirmed rarely." Uraniferous shales are from 1 to 17 

meters in thickness and underlie hundreds of square kilometers. "Each 

square kilometer has about 225 metric tons of U3O8 for each meter of 

thickness of 0.01 percent content."

Some typical shales are the Antrim and Chattanooga in the United 

States, with about 0.01 percent U3O8 ; the alum shale of Narke, Sweden, 

with 0.023 percent U3O8 ; the Cambrian and Ordovician shales of the Leningrad district, Russia, with from 0.008 to 0.003 percent U3O8 ; and the 

black siliceous schist(?) of Cambrian to Silurian age of the Ferghana

466353 58 2
268 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

region, Russia, with from 0.03 to 0.08 percent U3O8. The high values of 

the latter seem to be the result of surface enrichment.

The uranium in marine black shales was "a part of the original organicrich mud laid in brackish or salt water and adsorbed from it at pH 6 to 

7.5. The uranium content is generally greater in strata that accumulated 

very slowly * * *. Uranium was absorbed on the clay as phosphate and 

vanadate crystallites along with other metals." The thin black shales of 

Pennsylvanian age of the midcontinent, Illinois-Indiana, and western 

Appalachian regions are also potential large low-grade sources of 

uranium.

The geology and reserve data of the uraniferous shales and slates of 

Russia are discussed in some detail. By analogy to the reserve data of 

the foreign uranium-bearing black shales, "300 square miles may be expected to be underlain by such strata in the Chattanooga shale area 

[southeastern United States], and at the average content of 1,125 metric 

tons per square kilometer, it is not unreasonable to expect up to 810,000 

tons of U3O8 in this sort of occurrence * * *."

4 Bates, T. F., Strahl, E. O., Short, N. M., Silverman, E. N., and Camilli, 

Elena, 1954, Mineralogy and petrography of the Chattanooga shale 

[abs.]: Geol. Soc. America Bull., v. 65, p. 1230.

Detailed mineralogical and petrographic analysis of a drill core of the 

Chattanooga formation has resulted in a clearer picture of the relationship of uranium with the composition and texture of the black shale 

from the Highland Rim area of Tennessee.

Thin-section point counts, alpha-track counts, and quantitative mineralogical and chemical analyses of 60 samples from 35 feet of core have 

yielded statistically significant correlations between uranium and some 

of the shale constituents. The correlation is positive with respect to 

"blackness" of the sample, total carbon, pyrite, and total sulfur, and negative with quartz, feldspar, and clay and with Fe2O8. The absence of high 

correlation coefficients indicates that the uranium is not specific to any 

single constituent measured. On the other hand, certain relationships between uranium content and composition are apparent.

The upper member [Gassaway] of the formation is darkest, shows the 

least mineralogical and petrographic variation, and contains the highest 

concentration of uranium. The four lower members are more heterogeneous and consist of alternating gray and black beds. The gray beds are 

finer grained and contain more quartz, feldspar, and clay and less pyrite 

and organic matter than the black layers.

Autoradiographic studies demonstrate that the alpha-particle source 

material is localized about concentrations of organic matter and pyrite. 

Author's abstract

5 Beers, R. F., 1945, Radioactivity and organic content of some Paleozoic 

shales: Am. Assoc. Petroleum Geologists Bull., v. 29, p. 1-22.

Detailed measurements were made of the total alpha activity, the 

total beta activity, and the radium content of some Paleozoic sedimentary 

rocks taken from oil wells in Osceola County, Mich., and in Oklahoma. 

A method was developed for the rapid determination of the three radioactive constituents in ancient sediments (uranium, thorium, and potas-
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 269

sium-40) with the aid of a beta counter. In addition, quantitative analyses 

were made of the potassium, carbon, and hydrogen content of selected 

samples. A detailed description of the apparatus and methods of measurement used are given, as are several figures and tables of results.

Samples of cuttings of shale from oil and gas wells penetrating the 

Coldwater, Sunbury, Ellsworth, and Antrim shales and Traverse formation of Michigan and the Chattanooga, Woodford, and Sylvan shales of 

Oklahoma were studied. The radioactive elements in these rocks are in 

three principal loci: (a) in heavy minerals (that is, zircon), (b) in 

potassium-40, and (c) uranium and thorium in clays and organic materials. The studies indicate a positive correlation between the uranium 

and carbon content of the Antrim and Sunbury shales. Positive correlations were found between radioactivity and fineness of particle size, 

radioactivity and thorium-uranium ratio, and radioactivity and potassium content.

Methods cited as to how the uranium and thorium may have become 

associated with the sediments making up black shales are (a) adsorption 

to clay minerals during sedimentation, (b) inclusion in a stabilized colloidal form in the existing organic colloid, and (c) formation as a compound on, or adsorbed to, organic particles.

The high thorium-uranium ratio (8.0) observed in the samples of Antrim 

shale may have been due to a pH value in excess of 3.7 in the shallow 

sea that caused the thorium to be precipitated in excess of the uranium. 

"If all of these elements inhabit a colloidal dispersion at one time, then 

we have a mechanism which may account for the widespread and uniform 

distribution of radioactive substances and the correlative organic matter 

in these black shales." The selective action of the colloidal environment 

on the distribution of radioactivity and organic matter is illustrated by 

the fact that the radioactivity increases with the fineness of texture of 

the Antrim shale.

A hypothesis of the environmental conditions that may account for the 

distribution of the Sunbury and Antrim shales with their high content of 

uranium, thorium, potassium, and organic matter is set forth as follows: 

The complete cycle of sedimentary rock types from the Traverse formation through the Coldwater shale indicates a tectonic cycle during their 

formation. First, there was a stable period during which the limestone 

of the Traverse formation was deposited in a clear, deep epicontlnental 

sea. During this time the land was gradually weathered and eroded, and 

a deep residual mantle of fine clay and resistant heavy minerals, some of 

which were radioactive, was accumulated.

The sea became oscillatory as the period of unstability began and 

transgressed the adjacent low-lying lands. The residual debris was carried into the sea, the heavy and coarse fragments settling first and the 

fine particles remaining in colloidal suspension until an increased salinity 

was met in deeper water. Then the fine clay particles with their adsorbed 

uranium, thorium, and potassium and the organic matter were precipitated. The gentle oscillations of the sea may have been responsible for 

the further lateral spread of the fine sediments. At the close of Antrim 

time, the east edge of the sedimentary basin became the strand line and 

the clastic Berea sandstone was deposited. This evidently marked the 

period of maximum crustal upwarp. The Sunbury shale was then deposited at the beginning of a cycle of downwarping under conditions
270 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

similar to those in Antrim time. The maximum downwarping came as 

the predominantly calcareous Coldwater shale was being deposited. Thus, 

the full cycle had been completed.

The interaction of the organic matter and radioactive elements in shales 

may be favorable for petroleum genesis. There is "the possibility that 

a significant amount of organic matter may have been altered by alphaparticle bombardment." The original organic endowment and the products 

of this alteration are not known, however.

6 Beers, R. F., and Goodman, Clark, 1944, Distribution of radioactivity in 

ancient sediments: Geol. Soc. America Bull., v. 55, p. 1229-1254.

Over 300 samples of sedimentary rocks including limestone, sandstone, 

shale, arkose, and dolomite were tested for their radioactive constituents 

(uranium, thorium, and potassium-40) in order to evaluate the role of 

radioactivity in the genesis of petroleum. Quantitative analyses of the 

potassium, carbon, and hydrogen content of selected samples were made. 

A detailed description of the apparatus and methods of measurements, 

particularly the beta counter, is given.

Samples of shale from oil and gas wells penetrating the Chattanooga, 

Sylvan, and Woodford shales of Oklahoma and the Traverse formation, 

Ellsworth, Sunbury, Coldwater, and Antrim shales of Michigan were 

studied. The highest concentration of uranium, thorium, and potassium40 was found in black shale samples of the Antrim from a well in Osceola 

County, Mich. The highest total beta activity was observed in well 

cuttings of the Woodford chert (a correlative of the Chattanooga shale) 

from a well in the Seminole district, Oklahoma. Samples of organic 

black shale from the Antrim shale of Late Devonian age, Michigan, were 

selected for intensive study. A nearly 50-percent increase in beta activity 

was observed in the minus-200-mesh fraction as compared with the coarser 

fractions.

Conclusions resulting from this study are as follows: "In * * * organic 

black shales, potassium and uranium content increase directly with one 

another. Organic black shales show excellent correlation of uranium 

content, organic matter, abundance of colloidal size grades and a high 

thorium/uranium ratio * * *. All these correlations indicate possible 

genetic relationships in petroleum source beds and may have a bearing 

on one possible origin of oil."

7 Bell, K. G., 1954, Uranium and thorium in sedimentary rocks, in Faul, 

Henry, ed., Nuclear geology: New York, John Wiley & Sons, Inc., 

p. 98-114.

The uranium cycle is briefly reviewed. The uranium present in sediments may (a) be indigenous to the clastic sediments (mainly uraniferous 

resistates), (b) have been deposited syngenetically with the sediments, 

or (c) have been deposited epigenetically after sedimentation was completed. Some types of uraniferous sediments undoubtedly belong to more 

than one of these categories. The uranium in fine-grained elastics is 

predominantly indigenous whereas that of the chemical and carbonaceous 

sediments is commonly of syngenetic origin.

The chemical reactions that bring about the extraction and deposition
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 271

of uranium from aqueous solutions are not fully understood. The uranium 

may be (a) directly precipitated as insoluble compounds, (b) adsorbed 

by clays and carbonaceous materials, or (c) deposited in lesser amounts 

by gel precipitates of iron, aluminum, manganese, and silica. In addition, 

the uranium may have been an original constituent of some organic 

compounds, or it may have entered some minerals as an isomorphic substitution for calcium.

The distribution of uranium in sedimentary rocks indicates that a 

reducing environment containing organic matter and sulfides and little 

or no dissolved oxygen can precipitate uranium from solution. The 

deposition of uranium in carbonaceous shales may have taken place by 

both direct precipitation of insoluble compounds and by adsorption onto* 

clays and carbonaceous material.

There are two main groups of carbonaceous sediments: (a) the humie 

group with a low hydrogen and high carbon and oxygen content and (b) 

the sapropelic group with high hydrogen and carbon contents and little, 

or no, oxygen content. Some marine sapropelic black shales have been 

found to contain the greatest concentration of uranium of syngenetic 

origin of the sedimentary rocks. The uranium exists in an acid-soluble 

form in these uraniferous black shale formations, all of which have the 

following features in common: (a) They are generally less than 100 

feet thick, but represent long periods of very slow deposition, (b) contain 

abundant organic matter and sulfides, and are poor in carbonates, (c) 

are bituminous and probable source beds of petroleum, (d) are all preMesozoic in age, and (e) the greatest amount of uranium is found in 

nodules and layers of almost pure bitumen. Many marine black shales 

are nonuraniferous, and nonmarine black shales, oil shales, asphaltites, 

and coals are among the least radioactive of all sedimentary rocks.

Some examples of uraniferous marine black shales are the Chattanooga 

and Antrim shales of the United States, which contain about 0.01 percent 

UsOsj the alum shale of Sweden with as much as 0.023 percent U3O8 ; 

the shales of Cambrian and Ordovician age of the Leningrad district of 

Russia, which contain from about 0.008 to 0.03 percent U3O8 ; and the 

metamorphosed black siliceous schist of Cambrian to Silurian age of the 

Ferghana region of Russia with amounts ranging from about 0.03 to 0.08 

percent U3OS . The latter may possibly be surface enriched.

All marine phosphate formations that have been tested contain significant amounts of uranium. The phosphates resemble the black shales 

in that they are relatively thin and represent long periods of very slow 

deposition. They were probably formed along the edges of continental 

shelves. The uranium seems to be combined with the phosphate minerals, 

probably as an isomorphous substitution for the calcium. A reducing 

environment in the presence of organic matter may have aided in the 

concentration of uranium in the phosphatic sediments. Phosphatic nodules 

in some black shales are uraniferous, as at the top of the Checkerboard 

limestone and in the Fort Scott limestone of Pennsylvanian age in Oklahoma, but some phosphatic black shales in Kansas and Oklahoma have 

uraniferous layers of nonphosphatic shale. The phosphatic nodules, however, generally contain more uranium than the enclosing shale.

The book has an extensive bibliography of references dealing with geology and radioactive materials.
272 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

8 Bell, K. G., Goodman, Clark, and Whitehead, W. L., 1940, Radioactivity 

of sedimentary rocks and associated petroleum: Am. Assoc. Petroleum Geologists Bull., v. 24, p. 1529-1547.

Determinations of the radium and radon content of 21 sedimentary 

rocks and 7 associated crude oils have been made by the precision method 

developed by R. D. Evans. "The object of the investigation was to fix, if 

possible, the source of the radium emanation in the crude oils, to correlate the physical properties of the oil and its radioactivity, and to determine the radioactivity of some sedimentary rocks * * *."

The radioactive elements in sedimentary deposits "are laid down as 

components of some mineral in the beds or are precipitated with the 

sediment subject to existing physical, colloidal, and chemical conditions." 

The chemical effects of radioactivity in the generation of petroleum is 

suggested.

Radium determinations were made on six drill-core samples from oil 

and gas wells in the Fitts Pool, Pontotoc County, Okla., and in Texas, 

of shale ranging in age from Ordovician through Oligocene. The results 

of these tests, together with tests upon other sediments, are given in 

tabular form. The radioactivity of 5 shale samples from the Frio clay 

of Starr County, Tex., and the Woodbine formation of Navarro County, 

Tex., was found to be relatively high and fairly constant, averaging 

1.08 X10-12 grams of radium per gram of rock. "If uniform radioactivity 

in contemporaneous shales is real and is explicable by adsorption of 

uranium by colloidal constituents, then variation of radioactivity in shales 

of widely different ages may suggest variation of uranium in the sea 

during geologic time."

9 Beroni, E. P., and McKeown, F. A., 1952, Reconnaissance for uraniferous 

rocks in northwestern Colorado, southwestern Wyoming and northeastern Utah: U. S. Geol. Survey TEI-308A, 41 p., issued by U. S. 

Atomic Energy Cornm. Tech. Inf. Service Ext., Oak Ridge, Tenn.

In 1950 a reconnaissance examination was made to determine the 

radioactivity of coal and lignite of Tertiary age in the Green River basin 

and the Uinta basin. Several areas of copper-uranium mineralization 

and a few miscellaneous prospects also were examined. Only those 

deposits that contain 0.010 percent or more uranium or that represent 

large potential low-grade reserves, such as lignite, are discussed in the 

report.

Samples of phosphatic shale of the Phosphoria formation near Cokeville, Lincoln County, Wyo., contain as much as 0.027 percent uranium. 

Near Rawlins, Carbon County, Wyo., thin layers of green micaceous 

shale of Devonian (?) age are interbedded with pinkish-gray quartzite. 

The green shale and the chlorite coating of the quartzite contain about 

0.003 percent equivalent uranium. One grab sample of carbonaceous 

shale from the Mancos shale of Late Cretaceous age near Steamboat 

Springs, Routt County, Colo., contains 0.002 percent equivalent uranium, 

both in the sample and in 93.31 percent ash. Five beds of oil shale, 

totaling 6 feet in thickness, from the Laney shale member of the Green 

River formation near Rock Springs, Sweetwater County, Wyo., contain 

an average of 0.003 percent equivalent uranium.
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 273

10 Bradley, W. H., 1950, Occurrence of uranium deposits: Bull. Atomic 

Scientists, v. 6, no. 5, p. 149-152.

This article summarizes the work of the U. S. Geological Survey in 

the exploration for uranium deposits in the United States.

Uranium deposits are classified into three general types: (a) vein 

deposits, (b) deposits in sedimentary rocks, and (c) pegmatite deposits. 

The geology of the important uranium deposits of the world are briefly 

described. Under the heading "Deposits in sedimentary rocks," uraniumbearing marine rocks, including black shales and phosphorites are 

discussed.

Most of the known uranium-bearing marine rocks are either black 

shales or phosphorites. Large low-grade deposits of uranium-bearing 

marine black shales have been found in many areas of the world. Uranium 

is being extracted from some of these deposits the oil shales of Sweden, 

for example, which contain an average of 0.01 to 0.02 percent uranium. 

In the future, other similar deposits may well prove to be important 

sources of uranium.

Examples of uranium-bearing marine black shales include shales in 

Estonia and Eussia, which are similar to the oil shales of Sweden; the 

Chattanooga shale of east-central United States; the Woodford chert of 

Oklahoma; the Nonesuch shale of Michigan; and the Calico Bluff formation of east-central Alaska. All marine bituminous or carbonaceous 

rocks, however, are not appreciably uraniferous, and the nonmarine oil 

shales, coals, and associated rocks as a group are among the least radioactive of all rocks.

In the uraniferous marine shales, however, the most uranium generally 

is found in those rocks containing the most organic matter. The uranium 

content increases in direct proportion to the carbon content in the Sunbury and Antrim shales of Michigan. The highest concentrations of 

uranium are found in nodules and lenses of nearly pure bitumen in the 

shale of Sweden and in very thin layers of almost pure bitumen in the 

Chattanooga shale.

Significant deposits of uranium in phosphorite rocks are known in 

several regions of the world. In the United States the Phosphoria formation of the Northwestern States and the Bone Valley formation of 

Florida contain important low-grade concentrations of uranium. Uranium 

is concentrated in the phosphatic nodules of many black shales, such as 

those at the top of the Checkerboard limestone and in the Fort Scott 

limestone of Oklahoma; and at the top of the Bourbon formation and in 

the Hushpuckney and Stark shales of Kansas.

All marine phosphate formations that have been tested contain significant amounts of uranium. In general, the uranium content of the 

phosphorites increases in direct proportion to the phosphate content, 

although there are many exceptions to this rule when applied to the 

phosphorites of the United States.

11 Branson, C. C., Burwell, A. L., and Chase, G. S., 1955, Uranium in Oklahoma, 

1955: Oklahoma Geol. Survey Mineral Kept. 27, 22 p. See p. 19.

This booklet has been prepared for prospectors searching for uranium in 

Oklahoma. Several known uranium occurrences in the State are dis-
274 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

cussed. Maps of the major surface rock types and radioactive occurrences 

and a geological map of a part of southwestern Oklahoma are included. 

No radioactive deposits of proven commercial value have been found in 

Oklahoma to date (1955).

Under the heading "Phosphatic black shales," several shales that are 

notably radioactive are described. These are the Woodford and Chattanooga shales of Devonian and Mississippian age and shales of Pennsylvanian age from the Senora formation, the Marmaton group, and the 

Missouri series (includes the Checkerboard limestone). No figures are 

given to indicate the uranium content of these shales.

12 Breger, I. A., 1955, Radioactive equilibrium in ancient marine sediments:

Geochim. et Cosmochim. Acta, v. 8, p. 63-73.

The radioactive equilibrium of eight marine sedimentary formations 

was studied by means of direct determinations of the content of uranium, 

radium, and thorium and by alpha-particle counting techniques. "The 

maximum deviation from radioactive equilibrium that has been noted is 

11 percent indicating that there is probably equilibrium in all the 

formations analyzed."

Of the 8 formations studied, 6 are of Cretaceous age from the Gulf Coastal 

Plain of eastern Texas and southern Mississippi. The other two are the 

Miocene nodular shale of the Los Angeles Basin, Calif., and the Antrim 

shale of Devonian age from Osceola County, Mich., which contain 14.4 

and 17.5 ppm (parts per million) uranium (0.0014 percent and 0.0017 

percent), and 3.6 and 2.8 ppm thorium (0.0003 percent and 0.0002 percent), 

respectively. "The uranium content of marine sediments may be appreciably higher than the average values that have been reported for sedimentary rocks. Data show that there is up to fourteen times the percentage of uranium as of thorium in the formations studied, and that the 

percentage of thorium never exceeds that of uranium. While the proximity 

of a depositional environment to a land mass may influence the concentration of uranium in a marine sediment, this is not true with thorium."

13 Breger, I. A., and Deul, Maurice, 1956, The organic chemistry of uranium: 

Internat. Conf. on Peaceful Uses of Atomic Energy, Geneva 1955, 

Proc., v. 6, Geology of uranium and thorium, p. 418-421; U. S. Geol. 

Survey Prof. Paper 300, p. 505-510.

"It has become clear within recent years that coal or materials derived 

from plants are avid receptors for uranium." After a brief review of previous studies, the concentrations of uranium associated with carbonaceous 

materials and their probable genesis are considered for the following: 

Living plants, marine carbonaceous shales, carbonaceous limestones, coal, 

coalified logs, petroleum, asphaltic pellets, and unclassified materials.

Some marine carbonaceous shales have a uranium content of from 20 

to 50 ppm, few contain over 50 ppm. Early studies on the alum shale 

and associated kolm lenses of Sweden led to the conclusion that the uranium 

had been precipitated in the shale by means of organisms. The old organic 

complexes, such as the Babrosco "carbon" of Precambrian age in South 

Africa or the kolm of Cambrian age in Sweden, "are probably of algal 

origin" but little can be said regarding the origin of their contained 

uranium.

"Recent experimental studies * * * indicate physical rather than direct 

chemical association of uranium with the organic components of certain
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 275

shales." Probably "the decomposition of the organic matter under reducing conditions leads to the formation of hydrogen sulfide, vrhich is 

known to reduce the uranyl ion to the insoluble uranium dioxide." However, the organic matter may have served as a primary precipitant by 

forming a complex organo-uranium compound from the sea water. If 

this was true, then the chemical bonds between the uranium and the 

organic compounds have since been broken.

14 Breger, I. A., and Schopf, J. M., 1955, Germanium and uranium in eoalified 

wood from Upper Devonian black shale: Geochim. et Cosmochim. Acta, 

v. 7, p. 287-293.

Microscopic study of black, vitreous, carbonaceous material occurring 

in the Chattanooga shale in [Davidson County] Tennessee and in the 

Cleveland member of the Ohio shale in [Cuyahoga County] Ohio has 

revealed coalified woody plant tissue. Some samples have shown sufficient 

detail to be identified with the genus Callixylon. Similar material has been 

reported in the literature as "bituminous" or "asphaltic" stringers.

Spectrographic analyses of the ash from the coalified wood have shown 

unusually high percentages of germanium, uranium, vanadium, and 

nickel. The inverse relationship between uranium and germanium in the 

ash and the ash content of various samples shows an association of these 

elements with the organic constituents of the coal.

On the basis of geochemical considerations, it seems most probable that 

the wood or coalified wood was germanium-bearing at the time logs or 

wpody fragments were floated into the basins of deposition of the Chattanooga shale and the Cleveland member of the Ohio shale. Once wii;hin the 

marine environment, the material probably adsorbed uranium with the 

formation of organo-uranium compounds such as exist in coals.

It is suggested that a more systematic search for germaniferous coals 

in the vicinity of the Chattanooga shale and the Cleveland member of the 

Ohio shale might be rewarding. Authors' abstract

A small sample of coalified wood from the Chattanooga shale contains 

1.27 percent ash; this ash contains 2.58 percent uranium and about 4.0 

percent germanium. A sample of coal from the Cleveland member of the 

Ohio shale contains 1.7 percent ash ; this ash contains 0.50 percent uranium 

and 2.0 percent germanium.

15 Brown, Andrew, 1956, Uranium in the Chattanooga shale of eastern 

Tennessee: Internat. Conf. on Peaceful Uses of Atomic Energy, 

Geneva 1955, Proc., v. 6, Geology of uranium and thorium, p. 439-444; 

U. S. Geol. Survey Prof. Paper 300, p. 457-462.

The uraniferous Chattanooga shale of Alabama, Tennessee, and adjoining States in Southeastern United States is part of a widespread 

blanket of bituminous shales of Late Devonian and Early Missis sippian 

age which were deposited over much of central United States from New 

York to Texas.

This report concerns the most uraniferous part of the Chattanooga 

shale in the Eastern Highland Rim area of the Nashville dome and the 

Walden Ridge area, both northwest of Chattanooga, Tenn. The' Chattanooga shale dips eastward from the axis of the Nashville dome at the 

rate of 30 feet per mile to the Sequatchie Valley where it is broken by 

the Sequatchie overthrust fault in the vicinity of Walden Ridge. Here

466353 58 3
276 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

the average dip is 8° to the southeast. The Chattanooga shale in this 

area is of Late Devonian age and consists of two members, the Dowelltown and the overlying Gassaway. The Dowelltown member, which includes a basal sandstone, a black shale unit, and a gray shale unit, attains 

a maximum thickness of about 18 feet; the Gassaway member, which 

includes 2 black shale units separated by a siltstone unit, ranges in 

thickness from 7 to about 21 feet. The top black shale unit is the most 

widespread and most uraniferous unit of the Chattanooga shale; it 

ranges in thickness from 4 to 10 feet in Tennessee.

Analyses of two cores from drill holes near Smithville, Tenn., reveal 

that all units of the Chattanooga shale are composed chiefly of silicate 

minerals of silt and clay sizes; pyrite and carbon are next in abundance. 

The organic matter in the shale is composed largely of spores, and most 

of the uranium-rich stringers, formerly identified as asphaltite, are now 

known to be woody fragments.

Semiquantitative spectrographic analyses of samples from 3 cores of 

the total thickness of the Chattanooga shale and from 15 cores of the 

Gassaway member are summarized. The analyses show that the chemical 

composition is fairly constant, both vertically and laterally. No correlation between the uranium and the minor metal content could be made.

Although all units of rock in the Chattanooga shale contain more 

uranium than most marine shales, the uranium content varies from unit 

to unit. The top gray-shale unit of the Dowelltown member contains the 

least (0.001 to 0.002 percent uranium) and the top black-shale unit of 

the Gassaway member contains the most uranium (0.006 to 0.0086 percent). Only the Gassaway member can be considered a potential source 

of uranium under present conditions.

"No uranium minerals have been identified in the shale. The element 

is present as a separate colloidal phase disseminated through the organic 

matrix and is not chemically combined with the organic matter. Autoradiographic studies * * * demonstrate that the alpha-particle source 

material is localized around concentrations of organic matter and pyrite.'r

Observations in the field and reflectance studies in the laboratory have 

established a positive correlation between the "blackness" of the shale, 

which is a function of sulfide and carbon content, and its uranium content. Analyses of Chattanooga shale show a positive relationship between 

uranium content and (a) total sulfur content, (b) carbon content, and 

(c) pyrite content, "the preponderance of evidence points to deposition 

of the [Chattanooga] shale in a sea that was for the most part landlocked 

and comparatively shallow. The uraniferous Eastern Highland RimWalden Ridge area was apparently in the central and deepest part of 

this sea * * *. Lack of circulation on the bottom of such a sea would 

provide anaerobic conditions and permit carbonaceous material, which 

has a strong affinity for uranium, to accumulate." * * * "The suggestion that the high uranium content of certain black shales represents concentration of only normal quantities of the element in sea water over 

tremendously long periods of geologic time, and that no particularly uraniferous source material is necessary, may not apply to the Chattanooga 

shale." The uranium in the Chattanooga shale could have been concentrated in part from the small quantity of volcanic ash that probably fell 

and was transported into the sea. The landmass of crystalline rocks to 

the east also may have been a possible source of uranium.
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 277

For recent stratigraphic descriptions and nomenclature of the Chattanooga shale in the southeastern United States, see Hass, W. EL, 1956, 

Age and correlation of the Chattanooga shale and Maury formation: U. S» 

Geol. Survey Prof. Paper 286.

10 Brown, J. H., Jr., and Keller, W. D., 1952, Uranium in the clay of a 

black radioactive shale: Science, v. 116, no. 3023, p. 632-633.

A thin black radioactive shale layer in the Spergen limestone [now called 

Salem limestone] near Ste. Genevieve, Ste. Genevieve County, eastern 

Missouri, was studied in an attempt to determine the chemical association of the contained uranium. The presence of uranium and vanadium 

was determined spectrographically.

The uranium content of three size fractions of the shale was tested 

by the use of the direct fluorimetric method using a sodium fluoride flux. 

The shale fraction containing the greatest amount of carbon emitted 

the weakest fluorescence. Therefore, it was concluded that the uranium 

was associated with the clay fraction and not with the organic fraction.

Leaching experiments were conducted and it was found that hydrochloric, nitric, and sulfuric acids, aqua regia, and dilute sodium carbonate 

were effective solvents of the uranium in the shale. "Normal propyl 

alcohol dissolved a small amount which fluoresced weakly. Hot and cold 

water, ethyl alcohol, carbon disulflde and carbon tetrachloride, however, 

did not extract enough uranium to produce fluorescence."

An attempt was made to exchange the uranium in the shale cationically 

by using barium chloride and potassium chloride. It was concluded that 

the uranium was held in a condition not easily exchangeable. No information on uranium or vanadium content is given in this article.

An equivalent uranium content of 0.37 percent for this shale was reported in Muilenberg, G. A., 1949, Notes on uranium: Missouri Geol. 

Survey Inf. Circ. 5,18 p. See p. 9,17.

17 Burbank, W. S., and Pierson, C. T., 1953, Preliminary results of radiometric reconnaissance of parts of the northwestern San Juan Mountains, Colorado: U. S. Geol. Survey Circ. 236, 11 p.

In 1951 a reconnaissance was made of the radioactivity of the rocks of 

a portion of the northwestern San Juan Mountain region in parts of 

Gunnison, Ouray, San Juan, San Miguel, and Dolores Counties in southeastern Colorado. The localities examined include the uranium-bearing 

base-metal and precious-metal sulflde-type deposits in the Uncompahgre 

district of Ouray County and the Red Mountain district of Ouray and 

San Juan Counties and the uranium-bearing Precambrian slates and black 

bituminous shales of Jurassic age.

A one-foot channel sample of altered bituminous shale from the Pony 

Express limestone member of the Wanakah formation of Jurassic age 

hear the Pony Express mine, lower Uncompahgre district, contains 0.010 

percent uranium. Nearby unaltered shale from the same horizon was 

virtually nonradioactive. A chip sample of limonite-stained black slate 

from the Uncompahgre formation of Precambrian age near Bear Creek 

Palls, upper Uncompahgre district, contains 0.050 percent uranium. A 

spectroscopic analysis of this slate is included.

The uranium In the altered bituminous shale from the Pony Express 

limestone member of the Wanakah formation is thought to have been 

introduced by mineralizing solutions. The uranium in the black slate from
278 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

the Uncompahgre formation is believed to have had a dual origin: "The 

widespread radioactivity of the slate and the structural environment of 

local uranium concentrations are suggestive of an initial Precambrian 

low-grade concentration, which has been enriched locally by early Tertiary 

processes of mineralization."

18 Burton, V. L., and Sullivan, G. E., 1951, Carbon content and radiactivity 

of marine rocks: Am. Geophys. Union Trans., v. 32, p. 881-884; also in 

Eeport of progress Fundamental research on occurrence and recovery of petroleum, 1950-1951: New York, Am. Petroleum Inst., p. 221- 

224 [no date].

This is a report of studies of the radioactivity of sedimentary rocks 

made at the Massachusetts Institute of Technology in connection with 

fundamental research into the origin of oil sponsored by the American 

Petroleum Institute. The net beta count and organic carbon content of 

315 samples from 2 sandstone units, 2 limestone units, and 4 shale units 

were determined.

Shales, which make up 82 percent of all sedimentary rocks, "have by 

far the largest concentration of radioactivity." Organic matter, estimated 

at 1.6 times the percentage of organic carbon, is also more concentrated 

in the shales than in the limestones and sandstones. Determinations for 

organic carbon, potassium, and beta emission were made on samples of 

oil well cuttings and cores of four shale formations: the Miocene nodular 

shale from the Los Angeles Basin, the Cherokee shale (former usage) 

of Pennsylvanian age from Oklahoma, the Eagle Ford shale of Cretaceous 

age from eastern Texas, and the Eutaw formation of Cretaceous age from 

southern Mississippi. A more detailed study was made of the Miocene 

nodular shale (130 determinations) and Cherokee shale (105 determinations) because they exhibited the greatest radioactivity.

When the net beta counts (the beta activity due to potassium was excluded) were plotted against the average organic carbon content, an 

increasing and consistent linear relationship was observed. These results 

suggest a possible genetic relationship between the uranium, thorium, 

and carbon contents of the formations studied.

19 Butler, A. P., Jr., 1952, The Geological Survey's work on the geology of 

uranium and thorium deposits: U. S. Geol. Survey TEI-207, 26 p., 

issued by U. S. Atomic Energy Comm. Tech. Inf. Serv. Ext., Oak Ridge, 

Tenn. See p. 11,19-20,24.

This is a summary of the work done by the U. S. Geological Survey on 

the geology of uranium and thorium from 1839 to November 1851, and 

records the many hundreds of occurrences .of uranium, or #f aaaterials 

that might possibly be uraniferous, that were examined during that period. 

Other than sandstones, marine phosphorites and black shales are the 

principal uraniferous sedimentary rocks and their uranium content ranges 

from a few thousandths of a percent to about 0.02 percent. In general, 

the uranium in these marine sedimentary rocks is distributed rather uniformly in relatively thin beds of wide lateral extent, ranging In size from 

a few to several thousand square miles.

Brief statements are made about the studies of the Chattanooga and 

other Devonian shales, some shales of Pennsylvanian age, and the Phosphoria formation of Permian age; plate 3 of the report indicates areas 

where the radioactivity of these units has been measured. Other plates
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 279

indicate areas in the United States including Alaska whkh have been 

examined by the Geological Survey during the course of reconnaissance 

investigations for radioactivity.

Under the heading "Studies of Alaskan deposits," the results of reconnaissance investigations, mainly in east- and south-central Alaska, are 

discussed. Of the sediments examined, only the phosphate rocks in the 

Lisburne group of Mississippian age cropping out on the north flank of the 

Brooks Range of northern Alaska and the black shale beds at the base of 

the Calico Bluff formation, also of Mississippian age, in the upper Yukon 

River region of east-central Alaska are appreciably radioactive. The 

uraniferous phosphate rock in northern Alaska is similar in lithologic 

character and uranium content to that of the Phosphoria formation of 

Permian age in the northwestern States. The radioactivity of the black 

shales of the Calico Bluff formation "is comparable to that of the Chattanooga shale" of Devonian and Mississippian age in the Southeastern 

States. Most of the marine black shales examined in Alaska were only 

weakly radioactive.

20 Butler, A. P., Jr., and Schnabel, R. W., 1956, Distribution of uranium 

occurrences in the United States: Internat. Conf. on Peaceful Uses 

of Atomic Energy, Geneva 1955, Proc., v. 6, Geology of uranium and 

thorium, p. 224-230.

Butler, A. P., Jr., and Schnabel, R. W., 1956, Distribution and general features of uranium occurrences in the United States: U. S. Geol. Survey 

Prof. Paper 300, p. 27-40.

This report is a compilation of data regarding the general geology and 

distribution of the major types of uranium deposits in the United States 

and includes index maps showing the location and types of the major 

uranium occurrences. Under the heading "Uraniferous marine sedimentary rocks," uraniferous marine black shales and phosphate rocks 

are discussed.

In general, the more uraniferous marine black shales contain abundant 

plant remains, are relatively rich in iron sulfides, are noncalcareous, 

and some contain phosphate. Identifiable uranium minerals in these 

rocks are extremely rare.

"Most of the appreciably uraniferous carbonaceous black shales in 

the United States are distributed from the western limit of the Appalachian Mountains in Virginia, Kentucky, Tennessee, and Alabama, westward to the eastern front of the Rocky Mountains in Wyoming. "All are 

of Paleozoic age and contain 0.005 to 0.02 percent USO8 ." These include 

the Chattanooga shale in Tennessee and its stratigraphic equivalents in 

adjacent States westward to Oklahoma, and some thinner, less persistent 

black shales of Pennsylvania age in eastern Oklahoma and eastern Kansas 

and in southeastern Wyoming." Weakly uraniferous shales are known 

west of the Rocky Mountains, but in only a few places are these as rich 

in uranium as the Chattanooga shale.

21 Conant, L. C., 1956, Environment of accumulation of the Chattanooga 

shale: Internat. Conf. on Peaceful Uses of Atomic Energy, Geneva 

1955, Proc., v. 6, Geology of uranium and thorium, p. 435-438; U. S. 

Geol. Survey Prof. Paper 300, p. 463-467.

The Chattanooga shale that underlies central Tennessee and adjacent 

parts' of Kentucky, Alabama, and Georgia consists largely of interbedded
280 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

fine-grained black shale and gray claystone overlying a remarkable smooth 

peneplain of truncated gently-dipping sediments of Middle Ordovician to 

Early Devonian age. The formation, which averages 30 to 35 feet thick, 

represents most of Late Devonian time and is divided into the Dowelltown 

member and the overlying Gassaway member. Thin sandstone beds are 

at the base of each member; a thin, persistent bentonite bed is near the 

top of the formation; and scattered phosphatic nodules are in the topmost 

beds further to the northeast. The denser and darker parts of the shale, 

which have proved to be the most uraniferous, are made up of about 

25 to 30 percent clay and mica, 20 to 25 percent quartz, 15 to 20 percent 

organic matter, 10 to 15 percent pyrite, 10 percent feldspar, 5 percent 

chlorite, ferric oxides, and miscellaneous minerals. The fossil assemblage 

includes algae, plant spores, petrified logs, radiolaria, brachiopods, 

conodonts, and fish bones and teeth.

The uranium content is highest in the Gassaway member, which contains slightly more than 0.005 percent uranium. The uranium probably 

was brought into the depositional basin in normal quantities by streams 

from the surrounding land areas. The uranium is believed to have been 

extracted from sea water by organic matter in some unknown manner. 

Much of the uranium is "probably associated with the plant matter in an 

ionic form." The higher uranium content of the driftwood logs of 

Callixylon "probably results from the absence of mineral matter, and 

perhaps from longer exposure to water."

The environment of accumulation of the Chattanooga shale, as inferred 

from lithologic data and the regional, stratigraphic, and structural relationships, is as follows: (a) A broad shallow sea, at the most only a few 

tens of feet in depth, encroached slowly from the northeast across a 

very smoothly peneplained land surface, (b) The limestone peneplain 

contributed very fine mud, and probably aeolian dust, at a very slow 

rate (most of the coarse sediments from the highland areas were trapped 

in the deeper Appalachian geosyncline to the northeast), where it was 

deposited on a well-graded sea floor, (c) The water of the sea was 

stratified, with a strongly reducing bottom layer and an overlying layer 

of more aerated water where life could be sustained. (d> Conditions 

prevented strong wave or tidal action so that the bottom muds were 

subjected to only mild movement and sorting, (e) At the close of the 

Late Devonian, the sea had spread over a large area, inundating the 

peneplain and the low islands that had existed in the Chattanooga area.

Similar material is included in Conant, L. C., 1953, Shallow water origin 

of the Chattanooga shale [abs.]: Geol. Soc. America Bull., v. 64, p. 

1529-1530.

22 Deul, Maurice, 1955, Mode of occurrence of uranium in the Chattanooga 

shale [abs.]: Geol. Soc. America Bull., v. 66, p. 1549; abs., Econ, 

Geology, v. 50, p. 772.

The Chattanooga shale, an abnormally uraniferous marine carbonaceous 

shale of Late Devonian age, has been studied to determine the relationship of uranium to gross organic and mineral constituents. Mineral-rich, 

organic-rich, and uranium-rich fractions have been obtained mechanically 

from a shale sample containing 0.009 percent uranium and 13.7 percent carbon.
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 281

Separation of shale components after ball-mill grinding in a mixture of 

water and kerosene for several hundred hours yielded a mineral concentrate containing 0.0035 percent uranium and 4.7 percent carbon, an organic 

concentrate containing 0.0038 percent uranium and 39.8 percent carbon, 

and a middlings fraction, consisting of the finest particles, assaying 0.019 

percent uranium and 9.1 percent carbon.

With increased grinding time more uranium has been liberated from 

the shale components. The middlings fraction from a sample milled for 

1,361 hours contained 0.031 percent uranium and 26.7 percent carbon. 

This fraction, consisting of less than 8 percent of the total material, 

contained more than 24 percent of the uranium.

These experimental data indicate that uranium in the Chattanooga 

shale exists largely as a colloidal phase dispersed through the organic 

matrix and that most of the uranium is not now combined with the 

organic material or with the minerals. These conclusions are confirmed 

by other experiments where colloidal fractions markedly enriched in 

uranium were obtained by air elutriation of air-jet pulverized shale and 

by dialysis of a hydrosol of shale. Author's abstract

The technique for the separation of components in shales of the Chattanooga, Phosphoria, Dakota, Chinle, and Lockatong formations and 

the resulting analytical data (not including that on uranium) are given 

in Deul, Maurice, 1956, Colloidal method for concentration of carbonaceous 

matter from rocks: Am. Assoc. Petroleum Geologists Bull., v. 40, p. 909-917.

23 Deul, Maurice, and Breger, I. A., 1954, Uranium in carbonaceous rocks, 

Geochemistry and petrology, Geochemistry of uranium-bearing shales, 

in Geologic investigations of radioactive deposits Semiannual progress report, June 1 to Nov. 30, 1954: U. S. Geol. Survey TEI-490, 

p. 178 and 180-182, issued by U. S. Atomic Energy Comm. Tech. Inf. 

Service Ext., Oak Ridge, Tenn.

Samples of Chattanooga shale, of vanadium shale from the Phosphoria 

formation in Coal Canyon, Lincoln County, Wyo., and of shale from the 

Dakota sandstone near Gallup, McKinley County, N. Mex., were fractioned by ball-mill grinding in mixed media. "These shales were chosen 

because they represent different geologic environments and contain different percentages of uranium. All the shales have about the same percentage of organic material. Preliminary results * * * indicate that 

uranium is present in the Chattanooga shale [and the vanadium shale 

of the Phosphoria formation] as a separate colloidal phase disseminated 

through the organic matrix but not combined with the organic matter." 

Complete data (the percentages of ash, uranium, carbon, and hydrogen 

in various unrefined and refined separates) are listed in tabular form.

"Analysis of fractions from the Dakota shale [of nonmarine origin] 

show that the uranium is retained by and associated with the carbonaceous 

constituents and is not present as a separate phase." This contrasts 

sharply with the uranium association found in the Chattanooga and 

Phosphoria shale fractions.

"The organic concentrate from the Chattanooga shale exhibits no 

unusual trace-element enrichments. In contrast, the organic fraction 

from the Phosphoria formation contains striking enrichments of nickel, 

vanadium, copper, silver, and molybdenum; and the organic concentrate 

from the shale of the Dakota shale contains notable enrichments of copper,
282 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

lead, cerium, and lanthanum." * * * "The data obtained have clarified 

a number of points with regard to the mechanism responsible for the 

precipitation of uranium in carbonaceous shales."

24 Duncan, D. C., 1953, Reconnaissance investigations for uranium in black 

shale deposits of the Western States during 1951 and 1952: U. S. Geol. 

Survey TEI-381, 89 p., issued by U. S. Atomic Energy Comm. Tech. 

Inf. Service Ext, Oak Ridge, Tenn.

"Reconnaissance examinations for uranium in 80 formations containing black shale were conducted in parts of Arizona, Colorado, Idaho, 

Montana, Nebraska, Nevada, New Mexico, Utah, and Wyoming * * *." 

The search was directed primarily toward tests of thin black marine shale 

zones (about 100 feet or less thick) of wide areal extent similar to some 

of the larger known deposits of uraniferous black shales. "Most of the 

uranium-bearing black shales that were found * * * occur in rocks of 

Carboniferous and Permian ages."

Most of the black shales examined contain very little uranium. Samples 

from 13 of these shales, however, contain from 0.003 to 0.006 percent 

uranium and were collected from the following rocks: An unidentified 

black shale of Ordovician or Silurian age from central Nevada; an 

unnamed shale of Mississippian and Pennsylvanian age, Manning Canyon 

shale, the Oquirrh formation, and the Gardner dolomite all from central 

Utah; the Brazer limestone and the Park City formation from northern 

Utah; the Hermosa formation of southern Colorado; the Paradox formation and Belden shale from central Colorado; the Heath shale from central 

Montana; the Madison limestone from southern Montana; and the Lakota ( ?) sandstone of northeastern Wyoming.

Four of the shales locally contain from 0.011 to 0.026 percent uranium 

and are as follows: A black shale bed, 1 foot thick, in the Weber (?) 

quartzite of Pennsylvanian age, Lake County, Colo. (0.019 percent uranium, 

possibly of hydrothermal origin); a shale bed, 1 foot thick, in the Pony 

Express limestone member of the Wanakah formation of Jurassic age, 

Ouray County, Colo. (0.011 percent uranium, possibly of hydrothermal 

origin); several thin beds of black shale from the subsurface Hartville 

formation of Mississippian (?), Pennsylvanian, and Permian age in eastern 

Wyoming and western Nebraska (from a few thousandths to 0.019 percent 

uranium); and phosphate-rich beds from the Phosphoria formation of 

Permian age in Lincoln and Teton Counties, Wyo. (as much as 0.026 percent uranium). Of the shales examined, "only the phosphatic black 

shales of the Phosphoria formation appear to be sufficiently thick and 

extensive to be of possible economic interest."

25 Dunham, R. J., 1954, Black shale, Chadron area, Nebraska and South 

Dakota, in Geologic investigations of radioactive deposits Semiannual progress report, June 1 to Nov. 30, 1954: U. S. Geol. Survey 

TEI-490, p. 157-158, issued by U. S. Atomic Energy Comm. Tech. Inf. 

Service Ext, Oak Ridge, Tenn.

About 250 square miles in northeastern Dawes County and northwestern 

Sheridan County, Nebr., and southern Shannon County, S. Dak., were 

mapped on aerial photographs at scales of 1:20,000 and 1:31,680. Concentrations of 0.003 to 0.013 percent uranium occur in 2 kinds of deposits.
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 283

"Uranium is concentrated sporadically in the Carlile shale, Niobrara 

formation, and the Pierre shale, all of Cretaceous age, in gray shales and 

marls immediately below the base of an altered zone formed by weathering of the Cretaceous strata. The maximum known uranium content in 

shale of the altered zone is 0.01 percent, and in most places the content is 

less than 0.003 percent uranium. Greatest uranium content is generally 

restricted to the highest part of the highest and thinnest remnant or pinnacle of unaltered shale."

About 20 feet of the middle part of the Sharon Springs member of the 

Pierre shale exhibits a persistent radioactivity of from 2 to 4 times the 

normal background count. Two samples from the richest part of the 

interval show 0.003 percent equivalent uranium and 0.001 percent uranium 

and 0.007 percent equivalent uranium and 0.001 percent uranium. The 

Sharon Springs member is a hard black marine shale that bears abundant 

fish remains and pyrite.

A map showing exposures of the Sharon Springs member of the Pierre 

shale is included.

26 Eargle, D. H., 1954, Uranium in carbonaceous rocks, Black shales in Texas, 

in Geologic investigations of radioactive rocks Semiannual progress 

report, Dec. 1, 1953, to May 31, 1954: U. S. Geol. Survey TEI-440, p. 

132-136, issued by U. S. Atomic Energy Comm. Tech. Inf. Service 

Ext., Oak Ridge, Tenn.

The radioactivity of the Eagle Ford clay of Late Cretaceous age was 

studied from Dallas in northeast Texas to the Eagle Mountains in Hudspeth County, southwest Texas. The work included sampling from outcrops and well cores. In addition, a partial study was made of the 

radioactivity of several adjacent Cretaceous formations, and a few Paleozoic rocks were spot sampled in several localities. A table showing the 

average radioactivity and uranium content of the rocks examined is 

included.

Thirty-six samples of clay and siltstone from the Eagle Ford clay (or 

shale) contain, with one exception (0.002 percent uranium in Brewster 

County), less than 0.001 percent uranium. One sample of brown shale 

from the Maravillas chert of Late Ordovician age in Brewster County 

contains 0.003 percent uranium. Two samples of black shale from well 

cores of the Woodford chert of Devonian age in Terry County contains 

0.0045 percent equivalent uranium but less than 0.001 percent uranium. 

Clay from the Escondido formation of Cretaceous age in Medina County 

contains 0.002 percent equivalent uranium, and gray clays from the Del 

Rio clay (Grayson formation) and Pepper shale member of the Woodbine 

formation, both of Cretaceous age, contain less than 0.001 percent uranium.

27 Evans, R. D., and Goodman, Clark, 1941, Radioactivity of rocks : Geol. Soc. 

America Bull., v. 52, p. 459-90. See p. 59-460, 468, 475, and 487.

After an evaluation of the methods and data resulting from previous 

determinations of the radioactivity of terrestral rocks, many of which are 

discarded as unreliable, several hundred new measurements of the radioactivity of rocks are given. A description of the analytical methods used 

in obtaining these newer and more reliable data is included.

Most of the new determinations are of igneous rocks, but 28 are of sedimentary rocks, including 5 shales from unspecified rock units. Most of

466353 58 4
284 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

the sedimentary rocks tested were core samples obtained from oil and 

gas wells. Of the 5 shale samples, taken from oil and gas wells in Starr 

and Navarro Counties, Tex., 2 are Cretaceous and 3 are Oligocene in age. 

These shales contain about 0.0003 percent uranium, using the given radium 

determinations and the given conversion factor. By similar calculation, 

the average uranium content of the 28 sedimentary rock samples is less 

than 0.0002 percent.

28 Everhart, D. L., 1951, Geology of uranium deposits a condensed version, 

with mineral tables by Muriel Mathez: U. S. Atomic Energy Comm. 

RMO-732, 33 p., issued by U. S. Atomic Energy Comm. Tech. Inf. 

Service Ext., Oak Ridge, Tenn. See p. 20-22.

This report summarizes the geologic features of the major types of 

uranium deposits. Deposits in igneous and metamorphic rocks are discussed. Under sedimentary rocks the following are discussed: Uraniumbearing black shales, carnotite deposits, copper-uranium deposits, uraniumbearing asphalts, limestones, phosphorites, alluvial and placer deposits, 

and lacustrine-saline deposits.

"Comparatively low concentrations of uranium in vast tonnages of 

carbonaceous and bituminous shales have been known in many parts of 

the world for several decades." Since the discovery in 1893 of uranium 

in the black alum shale of Cambrian age in Sweden, uranium also has 

been found in certain black shales of Russia, Estonia, Alaska, and central 

United States.

The significantly uraniferous marine black shales are all very dark, 

have a high content of sulfide and organic matter, are low in carbonate, 

are in relatively thin units which are thinly bedded, and, so far as is 

known, are mostly pre-Mesozoic in age. The radioactive black shales of 

the United States are characteristically uniform in thickness and composition, and contain small abnormally radioactive lenses. The shales are 

generally composed of silica, organic matter or carbon, and clay minerals 

with associated pyrite, marcasite,, and phosphate.

The Chattanooga shale of Devonian and Mississippian age is cited as an 

example of the radioactive black shales in the United States. It ranges in 

thickness from 5 to 100 feet throughout most of its extent. The most 

uraniferous parts of the Chattanooga shale "are in central Tennessee and 

southern Kentucky where thousands of square miles of the uppermost part 

of the formation contain from 0.002 to 0.013 percent U8O8 and average 

0.008 percent UsOs. Formations correlative to the Chattanooga extending 

through Indiana, Kentucky, Ohio, Michigan, and New York are less 

radioactive, but the uranium content of the roughly equivalent Woodford 

formation of Oklahoma and Kansas is comparable [to that of the Chattanooga shale]. Certain black shales of Pennsylvanian age in Alabama, 

Kansas, and Oklahoma also range from 0.003 to 0.013 percent in UsOs 

content, but the average is somewhat less than that of the Chattanooga 

shale and they are not so widely exposed nor so minable."

"The mineralogy of the uraniferous black shales has not been completely solved as yet, and no definite uranium minerals are identifiable 

in most cases." The uranium is in the finer grained parts of the shale 

and is soluble in acid. "It may be incorporated into the crystal lattices 

of clay minerals and organic compounds * * *. All thin black shale 

formations of Paleozoic and, probably, pre-Cambrian ages, representing
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 285

periods of stable, slow sedimentation in shallow seas, are worthy of 

investigation if they afford large tonnages and may be mined at low costs."

29 Term, J. C., 1955, Radioactivity of coals and associated rocks in Beaver, 

Clearfleld, and Jefferson Counties, Pennsylvania: U. S. Geol. Survey 

TEI-468, 52 p., issued by U. S. Atomic Energy Comm. Tech. Inf. 

Service Ext., Oak Ridge, Tenn.

In 1953 a reconnaissance was made of the radioactivity of coal and 

associated rocks in the coal fields of west-central Pennsylvania. Selected 

beds were examined in the Pottsville, Allegheny, and Conemaugh formations of Pennsylvanian age. The greatest radioactivity of any rock 

group (0.016 percent uranium) was found in the uppermost section of 

the underclay underlying the Lower Freeport coal in Beaver County. The 

coal beds were generally the least radioactive of the rocks examined. 

A sample of the Lower Freeport coal in Beaver County, however, contains 

as much as 0.010 percent uranium.

Dark marine shale beds associated with the Lower and Middle Kittanning and the Lower Freeport coals of the Allegheny formation and the 

Brush Creek coal of the Oonemaugh formation contain from 0.002 to0.004 percent equivalent uranium at several localities in the 3 counties 

studied [Beaver, Clearfield, and Jefferson].

The structural attitude and the degree of weathering of the beds appear 

to have little effect on the amount of radioactivity contained in the rocks 

examined. No commercially significant uranium deposits were discovered 

during this study.

30 Fredrickson, A. F., 1948, Some mechanisms for the fixation of uranium 

in certain sediments: Science, v. 108, no. 2799, p. 184-185.

It is suggested that the wide distribution of uranium in the sedimentary crust of the earth is due principally to its tendency to form 

large UC>2++ ions. "Much of the uranium in shales may be in the form 

of adsorbed ions and not of discrete minerals." Studies indicate that "if 

the source rocks containing uranium are weathered to clays with a high 

base exchange capacity, these clays should show high radioactivity."

"A possible method of concentration of uranium in sedimentary deposits containing carbon may then be as follows:

"Uranium ions are released, on weathering, from the granitic, rhyolittc, 

etc., rocks in which they occur in relatively large amount and then are 

adsorbed by base-exchange phenomena on layer-lattice minerals such as 

certain clays." By aging of the clays or chemical or thermal change, 

the uranium might be displaced and again put into solution. The carbonaceous material in the path of the displaced ions would then concentrate and fix the uranium ions.

"For the concentration of uranium * * * it is probably important that 

an oxidizing environment prevail." Alkaline solutions would attack the 

carbonaceous material and release the uranium into a colloidal suspension. The uranium would then be adsorbed again on clays and similar 

minerals.

"Could such a process as this account for the high radioactivity of 

certain carbonaceous shales or have something to do with the formation 

of oil * * *?"
286 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

31 Glover, Lynn, 1955, Uranium in carbonaceous rocks, black shale investigations, Chattanooga shale in Alabama, Georgia, and Tennessee, in 

Geologic investigations of radiactive deposits Semiannual progress 

report, Dec. 1, 1954, to May 31, 1955: U. S. Geol. Survey TEI-540, 

p. 170-174, issued by U. S. Atomic Energy Comm. Tech. Inf. Service 

Ext., Oak Ridge, Tenn.

The Chattanooga shale was studied for radioactivity and sampled in 

the southern Appalachian region between Birmingham, Ala., and Knoxville, Tenn. In the vicinity of Birmingham the shale is absent, but 

farther to the northeast it is generally 10 to 40 feet thick. Phosphate 

nodules and chert beds are common in the black shale of this region. The 

phosphate and uranium content of the shale units is inversely proportional.

A sample of highly weathered coalified material from a bed about 

1 inch thick, in the top of the Maury formation in northwestern Georgia, 

contains from 1 to 5 percent yttrium in about 10 percent ash.

32 Gott, G. B., and Hill, J. W., 1953, Radioactivity in some oil fields of southeastern Kansas: U. S. Geol. Survey Bull. 988-E, p. 69-122.

"Abnormally high radioactivity in oil and gas wells in southeastern 

Kansas was noted in 1948 during an investigation to determine the value 

of commercial gamma-ray well logs in the search for radioactive ore 

deposits." Studies showed that many of the large deflections on the 

gamma-ray logs of these Kansas wells are caused by a radium-bearing 

precipitate, derived probably by solution and redeposition from adjacent 

rocks since the drilling of the well. These precipitates, generally associated with limestones in the Arbuckle group of Cambrian and Ordovician 

age, and the Kansas City group of Pennsylvanian age, contain as much as 

0.26 percent equivalent uranium, and were found in more than 60 oil and 

gas fields in Cowley, Butler, Marion, Sedgwick, and Greenwood Counties, 

Kans. Most of the other rocks in this area are not abnormally radioactive, though some large deflections on the logs are associated with 

marine black shales.

Gamma-ray logs and a few radiometric analyses of drill cuttings of 

Pennsylvanian black fissile shales indicate an equivalent uranium content of from 0.004 to 0.01 percent. A gamma-ray log of the Dilworth 

No. 2 Fee well (sec. 8, T. 33 S., R. 7 E., Cowley County) reveals a 

marked anomaly at the level of the Cherokee shale which exceeds the 

limits of the sensitive logging instruments and could not be recorded. A 

gamma-ray log of the upper gray shales of the Wabaunsee group shows 

an equivalent uranium oxide content of 0.02 percent. It is noted that 

A. L. Slaughter (1945, written communication) investigated the radioactivity of the exposed Pennsylvanian black shales and coals of Kansas 

and Oklahoma and found phosphatic nodules disseminated in the black 

shales to contain as much as 0.095 percent uranium. The uranium content of the black shales alone, however, was much lower.

Only meager information was obtained on the Chattanooga shale of 

Devonian and Mississippian age because most of it has been removed in 

the region by pre-Pennsylvanian erosion. A few gamma-ray logs and 

radiometric analyses, however, indicate that the equivalent uranium content of the Chattanooga shale ranges from about 0.002 to 0.007 percent.

Drill cuttings of a green shale and glauconitic sandstone from the
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 287

Simpson group of Ordovician age contain as much as 0.006 percent 

equivalent uranium.

33 Gott, G. B., Wyant, D. G., and Beroni, E. P., 1952, Uranium in black 

shales, lignites, and limestones in the United States, in Selected 

papers on uranium deposits in the United States: U. S. Geol. Survey 

Circ. 220, p. 31-35.

Small quantities of uranium occur in carbonaceous deposits at a great 

many localities in the United States, but the amount rarely exceeds 0.1 

percent. The most common uranium-bearing carbonaceous deposits are 

in the black marine shales, principally Paleozoic in age, that are exposed 

in the eastern and central parts of the United States. The uranium 

content of most of these shales ranges from a few thousandths to a little 

more than 0.01 percent. Uranium-bearing lignites and limestones also 

are discussed.

The uranium content of the Chattanooga shale ranges from 0.001 

to 0.03 percent, and data suggest a general correspondence between the 

uranium content and the (a) organic content, (b) iron sulfide content, 

and (c) vanadium content of the shale. The uranium content of the 

black shales of Pennsylvanian age in Kansas and Oklahoma is similar 

to that of the Chattanooga shale except that the Pennsylvanian shale* 

contain phosphatic nodules that have a much higher uranium content. 

Samples of a carbonaceous marine shale of Mississippian(?), Pennsylvanian, and Permian age [the Hartville formation] from an oil well in 

east-central Wyoming contain from 0.005 to 0.02 percent uranium. Thin 

beds of black shale in the Spergen limestone [now called Salem limestone] 

of Mississippian age in Ste. Genevieve County, Mo., contain as much as 

0.6 percent uranium.

34 Holland, H. D., and Kulp, J. L., 1954, The transport and deposition of 

uranium, ionium, and radium in rivers, oceans, and ocean sediments: 

Geochim. et Cosmochim. Acta, v. 5, p. 197-213.

Data that have accumulated over the past two decades on the concentration of uranium, ionium, and radium in ocean water and in oceanbottom sediments, are evaluated and rate equations descriptive of the 

economy and history of the elements are presented. "The important 

factors controlling the concentration of the radioelements in the ocean 

are the influx, the rate of radioactive decay, and the rate at which the 

radioelements are removed by sedimentation."

The uranium content of marine sediments is probably attributable to> 

several factors, including the original content of the constituent grainsderived from the land, uranium removed from the transporting streamsand from the ocean by the sediments, and the uranium removed by the 

marine organisms incorporated in the sediments.

The average uranium content of shales is 3.1±:0.3XlO"8 grams per 

gram and the fraction of the earth's land surface covered by shales i» 

on the order of 0.33±0.03. The estimated average uranium content of 

constituent grains that make up the shales on entering the oceans via 

streams is 1.8±0.4xlO-8 grams per gram and l.Ort0.5X10'' grams per 

gram uranium is added during sedimentation. "The geochemistry of 

uranium influx and deposition in shallow water are of major 

importance * * *."
288 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

35 Huddle, J. W., and Patterson, E. D., 1954, Uranium in carbonaceous rocks 

Coal and lignite in the eastern United States, in Geologic investigations of radioactive deposits Semiannual progress report, Dec. 1, 

1953, to May 31, 1954: U. S. Geol. Survey TEI-440, p. 100-101, issued 

by U. S. Atomic Energy Comm. Tech. Inf. Service Ext., Oak 

Ridge, Tenn.

Coal, lignite, and associated rocks in southwestern Pennsylvania, western Indiana, and southern Illinois were examined and sampled for radioactivity. No coal examined contains much more than 0.001 percent 

equivalent uranium.

Nine samples of a grayish-black marine shale of Pennsylvanian age, 

from 4 to 6 feet in thickness and overlying the No. V coal, contain from 

0.006 to 0.016 percent equivalent uranium at several localities in Warrick, 

Pike, Vigo, and Vermillion Counties in western Indiana. Grayish-black 

shale beds directly overlying the No. 5 and No. 6 coal units in southeastern 

Illinois are also radioactive. The No. 5 coal in Illinois is a correlative 

of the No. V coal in Indiana.

36 Kepferle, R. C., 1955, Uranium in carbonaceous rocks, Black shale investigations, South Dakota and northeastern Nebraska, in Geologic investigations of radioactive deposits Semiannual progress report, 

Dec. 1, 1954, to May 31, 1955: U. S. Geol. Survey TEI-540, p. 163-165, 

issued by U. S. Atomic Energy Comm. Tech. Inf. Service Ext., Oak 

Ridge, Tenn.

Analyses of about 300 samples of black shale from 32 localities in South 

Dakota and northeastern Nebraska indicate that the Sharon Springs member of the Pierre shale in that region contains 0.002 percent or less uranium. 

"The most uraniferous parts of the shale contain 0.005 percent or more 

uranium in zones averaging about 1 foot in thickness. At three localities 

these zones reach thicknesses of 3 to 6 feet; elsewhere they are less than 

1% feet thick. The most uraniferous parts of the zones are generally 

about 3 inches thick and contain as much as 0.017 percent uranium.

"Semiquantitative spectrographic analyses of 82 samples of the black 

shale from the Sharon Springs member indicate that the concentrations of 

molybdenum and iron tend to vary directly with the concentration of 

uranium, whereas the concentrations of aluminum, gallium, boron, titanium, magnesium, and sodium all tend to vary inversely with the 

concentration of uranium.

"Chemical analyses of 18 samples of shale from one locality indicate a 

strong positive relationship between the concentrations of uranium and 

arsenic, and a lesser positive relationship between the concentrations of 

uranium and selenium.

"From a study of the relationship between the concentrations of uranium 

and the elements which vary in concentration with respect to uranium, 

it appears that the uranium in fresh samples of the Sharon Springs 

shale was emplaced during the deposition of the shale, in a reducing 

environment where deposition of allogenic clastic sediments was slow."

A diagram showing spectrographic analyses of the shale is included in 

the report.
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 289

37 Krumbein, W. C., and Slack, H. A., 1956, Statistical analysis of low-level 

radioactivity of Pennsylvanian black fissile shale in Illinois: Geol. 

Soc. America Bull., v. 67, p. 739-762.

A sampling experiment utilizing the Brereton shale of Pennsylvanian 

age in southwestern Illinois was undertaken in order to (a) evaluate 

the average radioactivity of the shale and (b) detect regional radioactivity gradients. The mean equivalent uranium content of this 3-foot 

shale unit is 0.0075 percent.

An isopach map and a map showing the distribution of radioactivity of 

the Brereton shale in southwestern Illinois are included. A restricted 

shallow-water marine environment of deposition with low oxygen content and almost neutral pH conditions is described for the Brereton shale. 

It is believed that the Brereton sea, advancing eastward nr northeastward, slowly inundated the almost flat-lying peat bogs (now the No. 6 

coal). The normal open circulation of this sea was restricted at its 

margin, causing the waters to become deficient in oxygen content and 

rich in sulfides.

The uranium in the Brereton shale is thought to be associated with 

the pyrite-organic clay complex. Living marine organisms probably helped 

in the extraction and fixation of uranium from the sea water and later 

the uranium may have become associated with the iron sulfide and clay 

in the accumulating muck after the death of these organisms.

38 McKelvey, V. B., 1955, Search for uranium in the United States: U. S. 

Geol. Survey Bull. 1030-A, p. 1-64. See p. 14-16 and 37-40.

McKelvey, V. B., 1953, Search for uranium in the Western States [abs.]: 

Am. Assoc. Petroleum Geologists Bull. v. 37, p. 2614.

"The search for uranium in the United States is the most intensive 

ever made for any metal during our history * * *. The purpose of this 

report is to summarize briefly the information on the common uranium 

minerals; the kinds of deposits in which uranium is found; the methods 

used in the search for uranium; the important deposits found in this 

country thus far; the outlook for future discoveries; and the recent 

literature on the geology of uranium deposits in the United States."

Uraniferous Black Shale

Some bituminous marine black shales contain from 0.005 to 0.02 percent uranium and represent one of the world's largest potential sources 

of uranium. The distinguishing characteristics of the uraniferous shales 

are not fully known. As a group, however, they are from older formations; are sapropelic rather than humic in origin; highly carbonaceous 

and bituminous, high in sulfide content, generally somewhat phosphatic; 

but are noncalcareous. Their sediments accumulated very slowly, probably 

at the rate of only 1 foot per 200,000 to 1,000,000 years net accumulation 

as compared to 1 foot per 700 years for other shales, and probably under 

anaerobic conditions.

The alum shale of Late Cambrian age in Sweden and the Chattanooga 

shale of Devonian and Mississippian age of Southeastern United States
290 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

are important examples of these uraniferous shales. "The uranium in 

these shales is in acid-soluble form, but it probably does not occur in a 

distinct uranium mineral. In the Chattanooga shale it is concentrated in 

pyrite-organic-matter complexes" and in the alum shale, the largest 

amounts of uranium (as much as 0.5 percent) are in nodules and lenses 

of dark bitumen, known as kolm. Microscopic particles of kolm scattered 

through the alum shale may be the uranium carriers in the shale itself. 

"The uranium may occur both in phosphate and carbonaceous matter" in 

the Miocene nodular shale of southern California and the Cherokee shale 

(former usage) of Pennsylvanian age in Oklahoma. The uranium in a 

black shale in the Spergen limestone [now Salem limestone] of Mississippian age in Ste. Genevieve County, eastern Missouri, is in the fine clay 

fraction and not in the organic matter.

The most uraniferous parts of the alum shale of Sweden and the subsurface Hartville formation of Mississippian(?), Pennsylvanian, and 

Permian age in eastern Wyoming seem to have been deposited near the 

margins of deposition of those shales. "Very likely the uranium in black 

shales is extracted from the sea by plankton, either alive or dead. The 

reason uranium is more concentrated in some black shales than in others, 

however, is unknown." It seems that the controls for uranium concentration in these shales "have to do with the pH, redox potential, and 

other physico-chemical factors that affect the precipitation of uranium 

in the sea." Although the concentration of uranium in the widespread 

evenly distributed uraniferous marine black shales probably occurred as 

the sediments were being accumulated, there is evidence that the uranium 

in some of the more irregularly distributed nonmarine carbonaceous deposits was adsorbed from percolating waters long after their deposition.

"The most important uraniferous black shale yet discovered in the 

United States is the Chattanooga shale of Devonian and Mississippian 

age in Tennessee. The upper part of this formation contains vast quantities of uranium in concentrations of 0.01 percent or slightly less." The 

highest percentage of uranium in black shale (0.019 percent) thus far 

discovered In the United States is in the Mississippian(?), Pennsylvanian, 

and Permian (?) Hartville formation in the subsurface of eastern Wyoming. No uranium has yet been produced from the black shales in the 

United States.

Uraniferous Phosphorite

Marine phosphorites commonly contain from 0.005 to 0.03 percent uranium. Important examples are the Permian Phosphoria formation in 

western United States, the Upper Cretaceous and lower Eocene deposits 

of North Africa, and the Pliocene Bone Valley formation of Florida.

The uranium in the phosphorites seems to be chiefly in the mineral 

carbonate-fluorapatite where it probably substitutes for calcium. "The 

uranium content of the rock generally increases as the phosphate content 

increases, but deposits or beds richest in phosphate are not necessarily 

richest in uranium * * *," as is seen in the Phosphoria formation. This 

may be due to the inverse relationship between uranium and carbonate 

content.

The weakly phosphatic black shales in the Phosphoria formation contain little or no uranium. Phosphatic nodules in certain black shales, 

such as those of Pennsylvanian age in Kansas and Oklahoma, are gen-
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 291

erally more uraniferous than the enclosing black shales. The uranium 

content of phosphatie nodules on the present sea-bottom off the California 

const is about the same as that of older phosphorites. The uranium in 

most of the marine phosphorite deposits is believed to have been adsorbed 

from the sea water "at the time of deposition or before burial." An index 

map showing the location of the more significant deposits of uraniferous 

black shales and phosphorites is included.

39 McKelvey, V. E., and Carswell, L. D., 1956, Uranium in the Phosphoria 

formation: Internat. Conf. on Peaceful Uses of Atomic Energy, Geneva 1955, Proc., v. 6, Geology of uranium and thorium, p. 503-506; 

U. S. Geol. Survey Prof. Paper 300, p. 483-487.

Uranium-bearing marine phosphate deposits in the Phosphoria formation of Permian age and its stratigraphic equivalents cover an area of 

about 135,000 square miles in Montana, Idaho, Wyoming, Utah, and 

Nevada. Deposits of the highest grade, however, are in eastern Idaho and 

adjacent parts of Montana, Wyoming, and Utah. The phosphorites contain from 0.005 to 0.03 percent uranium and locally as much as 0.06 percent uranium in very thin layers.

The Phosphoria formation ranges in thickness from 200 to 1,500 feet 

and consists of 2 overlapping "couplet.?." each composed of a carbonaceous 

phosphatic shale member overlain by a clierty member. This represents 

nearly two cycles of transgression and regression of the Phosphoria sea.

Even though some of the phosphatic shale beds contain layers that 

resemble the uraniferous black shales of other formations, only the beds 

high in phosphate content are appreciably uraniferous.

The uranium content of the formation varies areally and with the 

phosphate content, as shown in maps and tables. The reasons for this 

areal variation are not well understood. The phosphate and uranium 

contents vary in direct proportion, but there are many exceptions seemingly due to other factors, such as organic content, carbonate content, 

textural variations, and effects of weathering. Most of the uranium is 

in carbonate-fluorapatite, probably substituting for the calcium. The 

uranium is thought to enter the carbonate-fluorapatite at the time of precipitation or after burial. Smaller concentrations of uranium may be 

present also in the organic matter or other constituents. The uranium 

and carbonate contents vary inversely with one another. Secondary 

mineralization has been observed and is believed to have resulted from 

leaching of uranium by surface weathering and subsequent migration 

in, and precipitation from, ground waters.

40 McKelvey, V. E., Everhart, D. L., and Garrels, R. M., 1955, Origin of 

uranium deposits: Econ. Geology, 50th Anniversary volume, 1905- 

193.";, part 1, p. 464-533. See p. 514-526.

After a brief summary of the geochemistry of uranium and the occurrence of uraniferous deposits, the geology, mode of occurrence, and 

origin of the following types of uranium deposits are discussed: Igneous 

rocks, veins, sandstone-type deposits, coal and associated carbonaceous 

shale, and marine sedimentary rocks (black shales and phosphorites).

Uraniferous marine black shales such as the alum shale of Sweden, 

the Chattanooga shale of Tennessee, and the Hartville formation of 

46635.3 58 5
292 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

eastern Wyoming contain from 0.005 to 0.02 percent uranium and minor 

amounts of other metals including vanadium, nickel, molybdenum, and 

zinc. The uraniferous black shales generally are sapropelic, rather than 

huniic in origin; are rich in sulfides, distillable hydrocarbons, and fine 

carbonaceous matter; are somewhat more phosphatic but less calcareous 

than other shales; and are relatively thin considering the period of time 

their sedimentation presumably represents.

Much of the uranium in the Chattanooga shale is in the organic 

matter-pyrite complexes and studies indicate that the uranium is not 

present as a discrete mineral. It is possible that the uranium in the 

alum shale of Sweden is carried mainly in fine-grained kolm pellets. It 

is evident from many investigations that uranium may occur in several 

forms in black shales, but the evidence "strongly suggests that the 

uranium in most black shales is held by one or another type of organic 

matter."

"The uranium in marine black shales and phosphorites was derived 

from sea water. The precipitation of uranium in the shales probably 

is brought about by chemical adsorption by living or dead plankton, but 

reduction evidently plays an important role in its precipitation and 

stabilization in the shale. Uranium in the phosphorites substitutes for 

calcium in the apatite structure." A list of 192 references, many dealing 

with uranium in carbonaceous materials, is included at the end of the 

report.

For information of a similar nature see also, McKelvey, V. E., Everhart, D. E., and Garrels, R. M., 1956, Summary of hypotheses of genesis 

of uranium deposits: Internat. Conf. on Peaceful Uses of Atomic Energy, 

Geneva 1955, Proc., v. 6, Geology of uranium and thorium, p. 551-561; 

U. S. Geol. Survey Prof. Paper 300, p. 41-53.

41 McKelvey, V. E., and Nelson, J. M., 1950, Characteristics of marine uranium-bearing sedimentary rocks: Econ. Geology, v. 45, p. 35-53.

Uranium occurs in abnormal concentrates in some marine sediments. 

The most important and widespread deposits are in black shales and 

phosphorites, many of which contain from 0.01 to 0.02 percent uranium. 

The beach placer deposits of Nome, Alaska, and possibly the Witwatersrand conglomerates of South Africa constitute the only other known 

significant occurrences of marine origin.

Uranium-Bearing Black Shale

Uranium in black shale was first discovered in 1893 in the Cambrian 

alum shale of Sweden. It has subsequently been found in the "black 

shales of several other formations, including the Dictyonema and Leningrad shales of Estonia and Russia, which are the stratigraphic equivalents of the alum shale of Sweden; the Precambrian Nonesuch shale of 

Michigan; the Devonian (?) Woodford chert of Oklahoma * * *; the 

Devonian and Mississippian Chattanooga shale of east-central United 

States and the Mississippian Calico Bluff formation of east-central 

Alaska."

The uranium-bearing marine shales have several features in common. 

"All are black or dark in color, rich in organic matter and sulfides, low 

in carbonate, relatively thin, and those known are of pre-Mesozoic age."
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 293

Most of them are of great lateral extent, contain little clastic material, 

and represent long periods of depositional stability. The uranium in 

the marine black shales described is syngenetic and is believed to have 

been chemically adsorbed by clay minerals or by organic matter. The 

strong positive correlation between uranium content and carbonaceous 

material in marine black shales suggested that the uranium has been 

adsorbed by the organic matter rather than by the clays. A list of 

formations containing black shale that may be uraniferous is included.

Uranium-Bearing Phosphorites

Uranium in phosphorite was first discovered in 1924 in the phosphorite 

deposits of Cretaceous and Eocene age in Algerio. Since then, uraniferous 

phosphorites have been discovered in many other parts of the world. 

In the United States, phosphorite in the Pliocene Bone Valley formation 

of Florida and in the Permian Phosphoria formation of the Northwestern 

States contain significant concentrations of uranium. In contrast to 

the marine phosphorites, the residual phosphate deposits so far tested 

do not contain significant amounts of uranium.

Uraniferous phosphatic nodules have been found in many black shales, 

such as those of Penusylvanian age in Kansas and Oklahoma. These 

phosphatic black shales "are a cross between the typical phosphorite deposits and the uraniferous black shales."

The phosphatic rocks that contain significant amounts of uranium range 

in age from Paleozoic to Cenozoic, are in relatively thin formations, and 

many are associated with unconformities. The uranium content generally 

increases with the phosphate content but decreases with an increase in 

the carbonate content.

The uranium content of the Phosphoria formation increases westward 

from Wyoming into Idaho where an increase in the total phosphate 

content causes a marked increase in total thickness of the formation. 

Since the uranium-phosphate ratio is not constant in the Phosphoria 

formation, it is thought that some of the uranium may be associated 

with the organic and clay fractions in addition to the usual fluorapatite 

association.

Origin

It is believed that the uranium in these various marine sediments had 

a syngenetic origin and was removed from the sea water (a) by direct 

chemical precipitation, (b) by its selective removal by certain marine 

organisms, or (c) by adsorption to clay or organic matter in an environment unfavorable for the accumulation of large amounts of clastic or 

carbonate materials.

42 McKeown, F. A., 1951, Reconnaissance of radioactive rocks of Vermont, 

New Hampshire, Connecticut, Rhode Island, and southeastern New 

York: U. S. Geol. Survey TEI-67, 46 p., issued by U. S. Atomic 

Energy Comm. Tech. Inf. Service Ext., Oak Ridge, Tenn. See p. 25-33 

and 43-46.

In 1948 a reconnaissance, using a car-mounted Geiger counter, was 

made in Vermont, New Hampshire, Connecticut, Rhode Island, and 

southeastern New York to test the radioactivity of roadside rocks and 

soils. The author observed abnormal radioactivity in the rocks and soils
294 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

of three areas which he called "radioactive provinces." These are (a) 

the Hudson Highlands of southeastern New York and the Housatonic 

Highlands of western Connecticut, with an estimated maximum equivalent 

uranium content of 0.240 percent; (b) central New England, with an 

estimated maximum equivalent uranium content of 0.006 percent; and 

(c) the Milton area, Chittenden County, northwestern Vermont, with an 

estimated maximum equivalent uranium content of 0.029 percent.

Abnormal radioactivity was found in the Hudson and Housatonic 

Highlands region in gneiss, schist, and pegmatite. The radioactivity of 

some of the gneiss is believed to be of sedimentary syngenetic origin. The 

radioactivity in the other gneisses, schists, and pegmatites, however, is of 

hydrothermal origin.

Abnormal radioactivity MI central New England was found in gneiss, 

schist, phyllite, slate, granite and pegmatite. Phyllite in the Orfordville formation of Middle Ordovician(?) age from 2 localities near Brattleboro in southeastern Vermont contains a field estimate of from 0.003 

to 0.005 percent equivalent uranium. Micaceous slate of early Paleozoic 

age in the Dixville Notch in northern New Hampshire contains a field 

estimate of 0.003 percent equivalent uranium. No laboratory analyses 

were made of these rocks. Black petroliferous phosphatic calcareous 

clay galls in intraformational breccias of the Milton dolomite of Late 

Cambrian age near Milton, Vt, contain an average of 0.006 percent 

uranium and as much as 8.06 percent PzOz and 0.04 percent V2O5 . A range 

in grade of 0.002 to 0.018 percent uranium was noted. The radioactivity of the rocks in the Milton area is believed to originate from 

uranium. Thorium, however, is believed to be the cause of most of the 

radioactivity of the other two "provinces" because chemical analyses 

on igneous and rnetamorphic rock samples have a high thorium content and a low uranium content.

"The manner in which the radioactive elements are combined with 

other elements in the rock is not known. Alpha radiographs of thin 

sections * * * show * * * no apparent centers of radioactive concentrations." Phosphate analyses indicate a direct relationship between the 

uranium and phosphate content. "The fact that the radioactive material 

apparently has a wide areal and narrow stratigraphic distribution and 

is disseminated in * * * the rock suggests that the radioactivity is a 

feature of the original sediments."

43 Mapel, W. J., 1956, Uraniferous black shales in the northern Rocky 

Mountains and Great Plains Regions: Internat. Conf. on Peaceful 

Uses of Atomic Energy, Geneva, 1955, Proc., v. 6, Geology of uranium 

and thorium, p. 445-451; U. S. Geol. Survey Prof. Paper 300, p. 469-476.

In 1953 a reconnaissance search for uranium in black shale was conducted in the northern Rocky Mountain and Great Plains regions. The 

black shales in these regions range in age from Precambrian to Late 

Cretaceous. Outcrops, drill cuttings, cores, and gamma-ray well logs 

were examined. The location and name of the formations examined and 

the maximum uranium content of the shale are shown in tabular form 

and on index maps.

A black shale sequence, ranging in thickness from a few inches to 100 

feet, at the base of the Madison limestone of Mississippian age, was 

sampled at 17 localities in Cache County, northwestern Utah, and in
URANIUM-BEARING MARINE BLACK SHALES EST UNITED STATES 295

southwestern and central Montana. The shale contains as much as 0.005 

percent uranium in Gallatin County, Mont.

Core chip samples of shale from oil and gas wells penetrating the Bakken formation (a correlative of the basal shale of the Madison limestone) were sampled in northeastern Montana and northwestern North 

Dakota. Some of this shale contains as much as 0.007 percent uranium. 

Samples from a well in Daniels County, Mont., contain an equivalent 

uranium content of as high as 0.010 percent but only 0.003 percent uranium. 

The disequilibrium was found to be caused chiefly by the presence of 

thorium 230 and radium, both daughter products of uranium. The 

radioactivity in the Bakken formation seems to differ "appreciably and 

with a definite pattern from place to place. Recognition of the pattern 

doubtless will help in outlying [outlining] areas in which maximum concentrations of uranium in the formation might be expected."

A black phosphatic shale sequence, ranging in thickness from a few 

inches to 75 feet, at the base of the Brazer limestone of Mississippian 

age, was sampled at 2 localities in southeastern Idaho and 1 locality in 

Rich County, northern Utah. The shale at the Idaho localities was 

virtually nonuraniferous; but an upper shale unit, 14 feet thick, and a 

lower shale unit, 8 feet thick, at the Utah locality contain as much as 

0.006 percent and 0.009 percent uranium, respectively.

The Heath shale, a marine black shale of Mississippian age, contains 

a reported maximum of 0.006 percent uranium in Fergus county, central 

Montana, but less than 0.003 percent equivalent uranium in Roosevelt 

County, northeastern Montana. "Gamma-ray log data from oil and 

gas wells indicate that a bed of Heath shale, 10 feet in thickness, may 

contain more than 0.01 percent equivalent uranium in McCone County, 

northeastern Montana, and that parts of the formation in Musselshell 

County, Mont., may be nearly as radioactive."

Samples of black shale beds as much as 6 feet in thickness, in the 

Minnelusa sandstone of Pennsylvania age, were taken from 2 oil and gas 

wells in southeastern Wyoming. The uranium content of the shale is 

reported to be from 0.005 to 0.019 percent. Data from gamma-ray well 

logs of Colorado shale of Cretaceous age in central Montana indicate as 

much as 0.008 percent equivalent uranium in Musselshell County and a 

range of 0.002 to 0.005 percent equivalent uranium for other parts of central Montana. Gamma-ray log data further indicate that black shale from 

the lower part of the Pierre shale of Late Cretaceous age in northeastern 

South Dakota may contain 0.008 percent equivalent uranium.

44 Moxham, R. M., and Nelson, A. E., 1952, Reconnaissance for radioactive 

deposits in south-central Alaska, 1947-49: U. S. Geol. Survey Circ. 184, 

14 p. See p. 1-6.

In 1947 a reconnaissance for radioactivity was undertaken in areas 

adjacent to highways. Known pegmatites and beach placers in southcentral Alaska also were examined.

Shale beds from the Kennicott formation of Early Cretaceous age in 

the Wrangell Mountains contain from an "insignificant amount" to 0.002 

percent equivalent uranium. Shale beds of the Matanuska formation of 

Late Cretaceous age in the Matanuska Valley which were tested were 

found to be virtually nonradioactive. An argillite of Mesozoic age along 

the Richardson Highway also is virtually nonradioactive.
296 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

45 Narten, P. F., and McKeown, F. A., 1952, Reconnaissance of radioactive 

rock of the Hudson Valley and Adirondack Mountains, New York: 

U. S. Geol. Survey TEI-70, 54 p., issued by U. S. Atomic Energy Comm. 

Tech. Inf. Service Ext., Oak Ridge, Tenn. See p. 7-10, 25-28.

In 1949 a reconnaissance for radioactivity, using a car-mounted Geiger 

counter, was made of the sedimentary and metamorphic rocks of Paleozoic 

age in the Hudson and Champlain Valleys of eastern New York and western Vermont and the metasedimentary and igneous rocks of Precambrian 

age in the Adirondack Mountains in eastern and central New York. The 

average equivalent-uranium content of the most radioactive Paleozoic 

sedimentary rocks is about 0.003 percent. The highest equivalent-uranium 

content of these rocks is estimated as 0.005 percent in some slates of Early 

Cambrian age near Fairhaven, Rutland County, western Vermont. Precambrian pegmatites were the most radioactive rocks encountered, containing as much as 0.043 percent uranium and 0.62 percent thorium.

One sample of each of the following argillaceous rocks of Paleozoic age 

in New York was submitted for analysis: A dark-gray shale from the Deepkill shale near Stuyvesant, Columbia County; a black shale from the 

Bakoven shale near Medway, Greene County; gray and black shale from 

the Esopus shale near Ravena, Albany County; black shale from the Canajoharie shale near Ballston Spa, Saratoga County, and a slate from the 

Hudson River group near Chatham, Columbia County. All of these samples 

contain 0.002 percent equivalent uranium and 0.001 percent uranium.

A reconnaissance examination for radioactivity was made of the following argillaceous rocks in New York: Slaty shale, phyllitic slate, and dark 

slate from the Hudson River group; phyllite and slate from the Berkshire 

schist; shale from the Rensselaer graywacke; slate from the Normanskill 

shale; shale from the Snake Hill formation and black shale from the 

Marcellus shale. A slate from the Bomoseen grit of Early Cambrian age 

from western Vermont also was examined for radioactivity. The average 

estimated equivalent-uranium content for all of these rocks is about 0.003 

percent.

46 Nelson, J. M., and Narten, P. F., 1951, Reconnaissance of radioactive rocks 

of Maine: U. S. Geol. Survey TEI-68, 43 p., issued by U. S. Atomic 

Energy Comm. Tech. Inf. Service Ext., Oak Ridge, Tenn.

In 1948 a reconnaissance for radioactivity, using a car-mounted Geiger 

counter, was made of roadside rocks, soils, and glacial materials in Maine. 

Abnormal radioactivity was found in granite, pegmatite, diorite, gneiss, 

schist, phyllite, quartzite, greenstone in tuff matrix, road metal, and glacial 

till. A sample of black phyllite of Silurian age contains as much as 0.003 

percent uranium. No uranium deposits of economic importance were found 

during this reconnaissance examination.

Samples of the abnormally radioactive rocks were collected and analyzed 

for radioactivity in the field and later in the laboratory. A sample of gray 

phyllite of Ordovician and Silurian age from the Seboomook area, Somerset County, in west-central Maine contains 0.002 percent equivalent 

uranium and 0.001 percent uranium. Three samples of black phyllite of 

Silurian age were collected from the Monson, Harrington Lake, and Kokadijo areas, Piscataquis County, In central Maine. These 3 samples contain from 0.002 to 0.003 percent equivalent uranium. No uranium was
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 297

found in the samples from the Monson and Kokadijo areas. The sample 

from the Harrington Lake are was not analyzed for uranium.

47 Nininger, R. D., 1954, Minerals for atomic energy: New York, D. Van 

Nostrand Co., Inc., 367 p. See p. 75-76 and 155.

This book is a comprehensive guide to exploration for uranium, thorium, 

and beryllium and includes data on the major producing and potential 

areas of the world.

Deposits in Phosphate Rock

Uranium is in the phosphatic Bone Valley formation of Florida and 

Phosphoria formation of northwestern United States and also in phosphatic nodules occurring in certain shales of Kansas and Oklahoma. 

Uranium-bearing phosphorites are also known from Russia, Egypt, Algeria, Tunisia, Morocco, and Nigeria. In Devon, England, uranium occurs 

in phosphatic nodules in shaly limestones. Nonmarine phosphates such 

as those of Tennessee and parts of Florida contain little uranium.

The uranium-bearing marine phosphorites range in age from Paleozoic 

to Pliocene and all seem equally favorable. In general, there is a good 

correlation between uranium and phosphate content. The uranium is 

associated primarily with the calcium phosphate mineral, fluorapatite, 

though in places uranium may be associated with clay minerals and 

organic matter.

The Phosphoria formation of Permian age, which is appreciably uraniferous, crops out in Montana, Idaho, Wyoming, and Utah. The uranium 

content varies considerably from place to place; it increases westward 

from Wyoming into Idaho and decreases westward in Montana. The 

formation is from 200 to 500 feet thick and the beds of phosphate contain 

much extraneous material. The beds (containing more calcium contain 

little uranium. The Phosphoria formation contains a small amount 

of many other metals including vanadium, which has been mined 

commercially.

Deposits in Black Shales

The uranium-bearing black shales have many features in common: 

(a) they are black and rich in organic matter and iron sulfides, (b) they 

contain very little lime, (c) they all contain petroleum which, however, 

appears to exist in inverse proportions to the uranium content, (d) they 

are all relatively thin formations that were deposited very slowly over 

a long period of time, and (e) most of them are geologically old formations. Only a few of the numerous black shales contain appreciable 

uranium. The carbonaceous or coaly type of black shale is virtually 

barren of uranium.

The uranium in the marine black shales, as well as in the phosphorites, 

is of syngenetic origin. The uranium in the black shales is probably 

associated with the clay minerals or the organic matter, for no discrete 

uranium minerals have been found. The uranium content is generally 

less than one-fifth of a pound per ton, and only the alum (kolm) shale 

of Sweden contains as much as one-half of a pound or more per ton.

The most promising domestic occurrence of uranium in black shales 

is in the Chattanooga shale in the Sparta-Smithville-McMinnville area 

midway between Knoxville and Nashville, Tenn. Other outcrops of the
298 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

Chattanooga shale and its equivalents in Alabama, Georgia, Kentucky,. 

Illinois, Indiana, Michigan, and Ohio, including the New Albany, Antrim, 

and Sunbury shales, contain lesser quantities of uranium. The 

Nonesuch shale of Michigan, the Woodford chert of Oklahoma, the CalicoBluff formation of east-central Alaska, and several other black shales in. 

the Great Plains and Rocky Mountain States contain traces of uranium.

Uranium occurs also in the black alum shales of southern Sweden, 

Estonia, and the Leningrad district of Russia. The Swedish deposits of 

Cambrian age were first discovered in 1893; some of these deposits were 

mined for radium in 1909. These shales have unique nodules and small 

lenses of almost pure hydrocarbon which contain as much as 0.5 percent 

uranium. Experimental extraction of uranium from these shales has. 

been effected only recently.

Uraniferous phosphatic nodules have also been described from black, 

shales of Pennsylvanian age of Kansas and Oklahoma and from black, 

shales of the English Midlands area.

An index map of the United States showing generalized areas of 

uranium-bearing shales is included on page 155.

48 Ostrom, M. E., Hopkins, M. E., White, W. A., and McVicker, L. D., 1955,. 

Uranium in Illinois black shales: Illinois Geol. Survey Circ. 203, 15 p.

"One hundred and seventy-five samples of dark-gray to black shale [of 

Ordovician, Devonian, Mississippian, and Pennsylvanian age] were taken, 

from outcrops in 44 Illinois counties * * *. The uranium oxide (UsO8 ) 

content of 15 of the shale samples having the higher percent equivalent 

uranium ranged between 0.001 and 0.014 percent. The uranium oxide 

averaged 0.002 percent lower than the percent equivalent uranium for 

these 15 samples. Phosphatic nodules and bands found in relatively small 

quantities in some black shales have a higher percent equivalent uranium 

than the shales in which they occur. The maximum uranium oxide content of the phosphatic materials investigated was 0.075 percent * * *. 

No obvious regional variations in the equivalent uranium values of the 

shales were noted."

Thirty-nine shale units of Pennsylvanian age, most of them associated 

with coal beds, were sampled. High values obtained are listed below:

UaOs

Shale "beds sampled Percent 

Above Upper McLeansboro coals. 0.012 

Above Cohn coal_______________ _ J .019 

Below Shoal Creek limestone________ - - *. 13 

Above Macoupin coal___________ . 014 *. 075 

Above No. 6 coal______________________ . 006 

Above No. 4 coal______________________ . 014 

Above No. 2 coal______________________ . 008 

Above Davis coal_____________________ .009 

Above Stonefort limestone member of the Tradewater

formation________________________ . 013 

At position of Reynoldsburg coal____________ . 001 

1 Analyses of phosphatic nodules.

A sample of shale from the Mountain Glen shale of Devonian age in 

Union County, southern Illinois, contains as much as 0.013 percent UsO».
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 299

A sample of shale from the New Albany shale of Devonian age in Hardin 

County, southern Illinois, contains as much as 0.006 percent U3OS.

49 Patterson, E. D., 1954, Radioactive coal and shale of Pennsylvanian and 

Permian age in northern West Virginia: U. S. Geol. Survey TEI-494, 

17 p., issued by U. S. Atomic Energy Comm. Tech. Inf. Service Ext., 

Oak Eidge, Tenn.

During 1953 the commercially important coal beds and associated shales 

in the Monongahela formation of Pennsylvanian age and coal and shale 

of the Dunkard group of Permian age were examined and sampled for 

radioactivity in eight counties in northern West Virginia. The shales of 

the Monongahela formation average about 0.004 or less percent equivalent uranium. The black and canneloid shales of the Dunkard group 

average about 0.002 percent equivalent uranium. Most of the rocks 

examined were nonradioactive. Coal samples of the Dunkard group contain as much as 0.003 percent equivalent uranium and the Monongahela 

formation, 0.001 percent or less equivalent uranium.

Eighty-eight samples, most of which were coal, were collected from 16 

localities. Six samples of black shale and gray to black siltstone from 

the Dunkard group of Permian age were collected in Wetzel and Marion 

Counties, W. Va. These 6 samples contain a maximum of 0.002 percent 

equivalent uranium. A sample of canneloid shale associated with the 

Washington coal of Permian age in 4 Marion*Ctrtmty contains*about 0.002 

percent equivalent uranium: Black^shales/siltstfcnes, and mudstones of 

Pennsylvanian age were not sampled because of the low radioactivity exhibited at their outcrops. These rocks are part of the Waynesburg coal 

[of the Washington formation], the Pittsburgh and Bedstone coals of the 

Monongahela formation, and the Freeport coal of the Allegheny formation.

50 Patterson, E. D., 1954, Radioactivity of some coals and shales In southern Illinois: U. S. Geol. Survey TEI-466, 23 p., issued by U. S. Atomic 

Energy Comm. Tech. Inf. Service Ext.. Oak Ridge Tenn.

In 1954 a reconnaissance examination was made of the radioactivity 

of the coal and carbonaceous shales of Pennsylvanian age in central and 

southern Illinois. Channel samples were collected of the commercially 

important coal beds and the hard black sheety roof shales in the Caseyville, Tradewater, Carbondale, and McLeansboro formations. The uranium 

content of most of the coal and blact shale sampled is less than 0.001 

percent. However, a sample of bright attrital coal from the Herrin No. 

6 coal bed of the Carbondale formation near Harrisburg, Saline County, 

contains 0.008 percent uranium and 0.125 percent uranium in the ash of 

the sample, and a sample of black hard pyritic shale overlying the Harrisburg No. 5 coal, Equality quadrangle, Saline County, contains 0.017 percent uranium and 0.027 percent uranium in the 61.4 percent ash of the 

sample.

Of the marine black shale beds sampled, only 3 contained more than 

0.001 percent equivalent uranium. These are as follows: (a) The shale 

directly overlying the Davis(?) coal of the Tradewater formation in 

Saline County contains from 0.002 to 0.006 percent equivalent uranium; 

(b) the shale directly overlying the Harrisburg No. 5 coal of the Carbondale formation in Saline, Williamson, Jefferson, and Gallatin Counties 

contains from 0.002 to 0.018 percent equivalent uranium; and (c) the
300 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

shale directly overlying the Herrin No. 6 coal of the Carbondale formation in Williamson, Perry, Randolph, and St. Clair Counties contains from 

0.005 to 0.007 percent equivalent uranium.

"It is evident that these black shales are radioactive over a wide area." 

The radioactivity seems to be higher in the thinner black shale beds that 

contain pyrite.

51 Pepper, J. F., 1953, Uranium in carbonaceous rocks, Reconnaissance, black 

shale in Eastern States, in Geologic investigations of radioactive 

deposits, Semiannual progress report June 1 to Nov. 30, 1953: U. S. 

Geol. Survey TEI-390, p. 125, issued by U. S. Atomic Energy Comm. 

Tech. Inf. Service Ext., Oak Ridge, Tenn.

"Preliminary survey [of the literature] shows that there are approximately 75 named black or partly black shales east of the Mississippi River 

besides a large number of unnamed black shales that are referred to in 

geologic sections in some areas."

Measurements of the radioactivity of the Dunkirk shale of Late Devonian 

age were made at 28 localities in west-central and western New York 

State. This shale was found to contain on the order of 0.003 to 0.004 

percent equivalent uranium. "The radioactivity appears to decrease from 

west to east, perhaps related to an increase in the silt content of the 

shale."

52 Rankama, Kalervo, and Sahama, T. G., 1950, Geochemistry: Chicago, I1L, 

Chicago Univ. Press, 912 p. See p. 636-638.

This comprehensive review of geochemistry is divided into two main 

parts: (I) "general geochemistry" and (II) "manner of occurrence of 

the elements." In Part II, one-chapter each on uranium and thorium is 

included. The geology of uranium is discussed under the subheadings: 

"Abundance and general geochemical character," "Uranium in igneous 

rocks," "Cycle of uranium," "Biogeochemistry of uranium," and "Ores of 

uranium."

Some terrigenous sediments are rich in uranium because they contain 

uranium-bearing detrital heavy minerals. From the few determinations 

of uranium in sediments, it is concluded that the amount of uranium is 

small in sediments containing little or no organic matter.

The concentration of uranium by biologic processes is considered an 

important reason for the enrichment of uranium in some sedimentary 

rocks. Carbonaceous marine shales contain more uranium than other 

sediments and even more than most granites. It is believed, also, that 

the uranium may have been precipitated as a sulfide, along with iron, in 

the original sapropelic sediments and, in some places, along with vanadium, 

molybdenum, and nickel. It has been found that the uranium and potassium content of organogenic black shales and igneous rocks increase 

directly with one another.

Kolm, an ash-rich coal in the alum shales of Sweden, contains as much 

as 1 percent uranium. The bulk of the alum shales, however, contains 

an average of from 50 to 100 grams of uranium per ton with some values 

as high as 200 grams of uranium per ton.

An extensive bibliography and several geochemical tables on uranium 

are included.
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 301

53 Boss, V. F., 1952, Autoradiographic study of marine shales: Econ. Geology, 

v. 47, p. 783-793.

An autoradiographic study of five marine shales was undertaken as a 

part of the research sponsored by the American Petroleum Institute into 

the influence of radioactivity on the natural production of hydrocarbons 

from organic matter in sediments. The purpose of the study was to 

determine the source of the radioactivity by recording on sensitized nuclear emulsions the tracks of the alpha particles in the shales. Distribution curves of alpha-particle tracks and photomicrographs of the tracks 

are included.

Investigations of kolm from the alum shale of Sweden indicate that the 

radioactivity is associated largely with the inorganic constituents which 

are chiefly fine-grained pyrite, phosphate, and carbonate with some salts 

of uranium. "The radioactivity is often concentrated at the surfaces of 

colloidal grains." Some radioactivity, however, also was observed in 

association with the organic matter.

The radioactivity of the Woodford shale of Texas, with its finely disseminated pyrite, is mainly associated with certain mineral grains. The 

seasonal white layers and grains of phosphate in the Woodford shale in 

Oklahoma exhibit about three times the radioactivity of the surrounding 

organic matter. There may be a relationship between the uranium and 

the mineral sulfides. Studies of the Cherokee shale (former usage) of 

Oklahoma revealed that the radioactivity is largely associated with phosphatic nodules which are randomly distributed throughout the shale. 

The organic matter which surrounds these nodules exhibited only a small 

amount of radioactivity. The radioactivity of the Miocene Playa del Rey 

shale [Miocene nodular shale of this paper] of southern California is "more 

extensively localized in the inorganic nodules and layers than in the 

organic layers and veinlets."

Conclusions are that (a) "the radioactivity of the shales investigated is 

associated with both the organic and the inorganic matter, (b) the radioactivity is concentrated to a greater extent in the inorganic matter by 

a factor of 2.5," and (c) alpha particles originating in inorganic matter 

close to organic matter "might have been effective in transforming the 

latter into hydrocarbons."

54 Ruch, J. W., 1954, Status of uranium recovery from low-grade sources: 

Mines Mag. [Colorado], v. 44, no. 3, p. 105-106.

Problems encountered in processing several types of uranium ores are 

reviewed briefly. These include ores from vein deposits, Colorado Plateau deposits, and various byproduct sources such as the Rand deposits 

of South Africa, the phosphate deposits of Florida and northwestern 

United States, and the Chattanooga shale deposits of southeastern United 

States. These materials range in grade from perhaps 0.005 to about 0.50 

percent U3O8.

The Chattanooga shale is a very low grade but uniform and widespread deposit. It is a bituminous shale containing about 60 to 80 ppm 

of uranium but only about one-third the oil potential of the oil shale in 

the Green River formation of Colorado and Wyoming. "If this large 

potential source is ever to be a uranium producer, the recovery of sulphur 

and hydrocarbon values appears mandatory." So far, attempts at bene-
302 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

ficiating Chattanooga shale have met with little or no success, even though 

most known physical methods have been tried.

55 Runnels, R. T., Kulstad, R. O., McDuffee, Clinton, and Schleicher, J. A., 

1952, Oil shale in Kansas: Kansas Geol. Survey Bull. 96, pt. 3, 

p. 157-184. See p.183-184.

A stratigraphic and petrographic description of the oil shales of Pennsylvanian and Cretaceous age in Kansas is presented. Total recoverable oil from the shales that contain over 5 gallons per ton is estimated 

as about 3 billion barrels.

Other possible uses for these oil shales include the recovery of phosphate and uranium. These shales contain, chiefly in phosphate nodules, 

about 136 grams of uranium per ton of shale (0.0136 percent).

56 Runnels, R. T., Schleicher, J. A., and Van Nortwick, H. S., 1953, Composition of some uranium-bearing phosphate nodules from Kansas 

shales: Kansas Geol. Survey Bull. 102, pt. 3, p. 93-104.

The phosphatic nodules in 7 black shales of Pennsylvanian age from 

11 localities in eastern Kansas contain an average of 30.2 percent P2Os, 

0.017 percent UaOs, and 3.2 percent fluorine. Nodules from the Muncie 

Creek shale member of the lola limestone from Wyandotte County have 

the highest phosphate content (37.34 percent) and the highest uranium 

oxide content (0.03 percent) of any of the nodulgs.analyzed* The mineral 

in these nodules is tentatively identified as a carbonate-bearing fluorapatite, though chemically the component percentages lie between those of 

fluorapatite and dahllite.

As shown by a series of graphs, the uranium oxide, fluorine, and calcium 

oxide contents of the nodules generally increase with the increase in 

phosphate content, and as the fluorine content increases, so does the 

uranium oxide content. Thus, "if a location where the phosphate concentration in the nodules is 35 percent were selected, then slightly more 

than 0.02 percent U3O8 could be expected * * *" and if "the maximum 

phosphate content of 42 percent were obtained, 0.04 percent or more UsO8 

would be present."

57 Russell, W. L., 1944, The total gamma-ray activity of sedimentary rocks 

as indicated by Geiger-counter determinations: Geophysics, v. 9, p. 

180-216.

Geiger-counter determinations of the gamma-ray intensity of 510 

rock samples have been made to determine the average radioactivity 

and frequency distribution of radioactivities of the various types of 

sedimentary rocks. The results, expressed in units of gamma-ray intensity, show that limestones, sandstones, and dolomites are of relatively 

low radioactivity, shales much higher, and black bituminous shales highest 

of all. The new data on the gamma radiation of the sediments may be 

used to improve the interpretation of radioactivity logs and to determine 

the values of surface radioactivity surveys. Author's abstract

A listing of the radioactivity determinations and location, formation, 

age, and lithologic character of the 510 samples is included. The average 

radioactivity of 164 shale samples is 16.2 units (each unit is equivalent 

to 1X10"12 grams of radium per gram of rock). The highest radioactivity 

in the sequence of averages for lithologic types is 26.1 for 40 black and
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 303

grayish-black shale samples. Generally, the more calcareous or sandy the 

shale, the less the radioactivity. "Another general rule is that the darker 

the shade of a rock, the greater its radioactivity * * *." This increase 

in radioactivity as the shade grows darker is probably related to the 

increase in organic matter.

The shale samples studied were from both outcrops and wells in a 

number of areas in the United States, Venezuela, and Trinidad; the shale 

formations ranged in age from Ordovician to Pliocene. The highest 

radioactivity (equivalent to 104 to 220XlO"12 grams of radium per gram 

of rock) of any rock measured was from phosphatic concretions in thin 

black shales associated with the Oologah limestone and the Checkerboard limestone. Both are of Pennsylvanian age and were sampled in a 

quarry near Tulsa, Okla. The highest radioactivity of any shale studied 

was from a black shale of Pennsylvanian age overlying the No. 2 coal in 

western Illinois. Other high-radioactivity determinations are from the 

Chattanooga shale of northeastern Oklahoma, eastern Kentucky, and 

Illinois, and from several black shales of Pennsylvanian age and their 

associated phosphatic nodules of Oklahoma.

58 Russell, W. L., 1945, Relation of radioactivity, organic content, and sedimentation : Am. Assoc. Petroleum Geologists Bull., v. 29, p. 1470-1493.

"A comparison between the radioactivity and organic content of 510 

samples of sedimentary rocks (see Russell, W. L., 1944) indicates a 

marked relation between certain types of organic content and radioactivity. Marine oil shales are associated with exceptionally high radioactivity, coals with abnormally low radioactivity, and other types of 

organic matter with intermediate radioactivities." Calculating from 

figures given, Russell suggests that the average uranium content of all 

shales is probably about 0.003 percent. Russell also suggests that the 

uranium in shales may be (a) indigenous in the mineral grains, (b) 

extracted from solution by organisms, (c) precipitated from solution in 

a reducing environment, or (d) adsorbed by clay minerals. "Shales which 

yield oil when distilled are in general much more radioactive than those 

containing other types of organic matter. An analysis of the material 

balance between sedimentary and igneous rocks indicates that the sediments should have about the same radioactivity as the igneous rocks from 

which they were derived; the averages of the writer's tests seem to 

confirm this conclusion if the igneous source of the sediments resembles 

a granite."

From available sample tests, it is suggested that the Chattanooga 

shale of Oklahoma is more radioactive where it is thicker, though it is 

probably the chemical nature of the environment rather than the speed 

of deposition or relative thickness which controls the concentration of 

radioactive matter. "An analysis of the data bearing on the radioactivity 

of deep-sea deposits and oil shales indicates no evidence of a general 

increase in radioactivity with slowness of deposition." The fact that 

shales of Paleozoic age have a higher average radioactivity than younger 

shales is not because the Paleozoic shales are older, but that certain 

tectonic and chemical conditions were more prevalent during the Paleozoic era which led to a higher concentration of radioactive materials 

being deposited.
304 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

Determinations of radioactivity, indications of organic content, and 

lithologic characteristics are presented in tabular form.

59 Schnabel, E. W., 1955, The uranium deposits of the United States: U. S. 

Geol. Survey Mineral Inv. Resource Map MB 2.

This is a map (scale 1:5,000,000) of the United States showing the 

location of the principal types of uranium deposits. The map is keyed 

to a listing of these deposits and brief descriptions of the principal types 

of deposits are given. A short bibliography is included.

The outcrop of the Chattanooga shale, a marine black shale formation 

containing small percentages of uranium, is shown in green in the southeastern and south-central United States. The Woodford chert and 

Phosphoria formation are similarly indicated.

 60 Schopf, J. M., 1953, Search for, and geology of, uranium in carbonaceous 

rocks, black shale investigations, organic matter of the Chattanooga 

shale, in Search for, and geology of, radioactive deposits Semiannual progress report, Dec. 1,1952, to May 31, 1953: U. S. Geol. Survey 

TEI-330, p. 146-152, issued by U. S. Atomic Energy Comm. Tech. 

Inf. Service Ext., Oak Eidge, Tenn.

Studies of parts of two drill cores of the Chattanooga shale were made 

to determine whether a correlation between laminae could be established 

over a distance of half a mile. No periodicity in the thick or thin bands 

was noted and "variation in the persistence of microlaminae" could be 

demonstrated in individual core specimens.

Identifiable plant materials in the Chattanooga shale include Foerstia, 

a group of planktonic marine algae, drift wood of Callixylon, and one 

large algoid plant, Prototaxites. Some "nearly pure coaly mineral-free 

streaks that probably represent the bituminous remains of Callixylon * * * 

have proved [to be] unusually radioactive."

"Seven varieties of anomalous spore-like bodies are distinguished among 

organic constituents of Devonian black shale * * *. Abundant spores of 

undoubted land plants have been found, but * * * these contrast strongly 

with the spore-like microfossils * * *" of uncertain affinity referred to 

the form genus Tasmanites. "Usually the latter types are dominant [in 

the Chattanooga shale] and land plant spores are rarely seen."

Segregations of Foerstia thalli were made from the Huron member of 

the Ohio shale collected near Columbus, Ohio, and ash, colorimetric oil 

assay, uranium, and semiquantitative spectrographic determinations were 

made. Cu, Mo, Mn, V, Y, and U are shown to be more abundant in the 

ash of the Foerstia than in the ash of the shale matrix. The determination of organic elements in the Foerstia concentrate is also shown. These 

data are preliminary and data from more sample localities "would aid in 

showing whether any of the trends of variation between the organic concentrate and matrix are consistent * * *«" These studies may reveal a 

systematic variation in organic elements as does coal in a different 

depositional environment.

4ft. Snider, J. L., 1953, Radioactivity of some coal and shale of Pennsylvanian 

age in Ohio: U. S. Geol. Survey TEI-404, 22 p., issued by U. S. Atomic 

Energy Comm. Tech. Inf. Service Ext., Oak Ridge, Tenn.
^URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 305

Measurements were made of the radioactivity of the commercially important coal beds and associated rocks of the Pottsville, Allegheny, and 

Monongahela formations of Pennsylvanian age in eastern Ohio.

Only 5 samples contain an estimated 0.001 percent or more equivalent 

uranium; 2 of these were shale and 3 were coal. Two samples of shale, 

both from just above the Middle Kittanning coal of the Allegheny formation, were analyzed in the laboratory. One of these, from a bed of fossiliferous and pyritiferous marine shale about 6 feet thick (from Carroll 

County) contains 0.0004 percent uranium, 89.2 percent ash, and 0.0005 percent uranium in ash. The other sample, from a bed of fossiliferous 

marine shale about 6 inches thick (from Tuscarawas County) contains 

0.003 percent equivalent uranium but only 0.0007 percent uranium, 88.6 

percent ash, and 0.0008 percent uranium in ash.

None of the rocks sampled contain sufficient uranium to be of economic 

importance as a source of uranium at present.

<82 Snider, J. L., 1953, Reconnaissance for uranium in coal and shale in 

southern West Virginia and southwestern Virginia: U. S. Geol. Survey 

TEI-409, 28 p., issued by U. S. Atomic Energy Comm. Tech. Inf. Service Ext., Oak Ridge, Tenn.

In 1952 a reconnaissance for uranium in coal and associated rocks was 

made in southern West Virginia and southwestern Virginia. In addition 

to checking the outcrops with radiation-detection equipment, channel 

samples of coal, shale, and clay of Late Devonian, Mississippian, and 

Pennsylvanian age were collected for laboratory analysis. Two channel 

samples of a black fissile shale of Late Devonian age from Lee County, 

Va., contain as much as 0.004 percent equivalent uranium. Other sandstone and shale associated with the coal beds contain from 0.001 to 

0.003 percent equivalent uranium. All the coals sampled contain 0.001 

percent or less equivalent uranium.

The results of radiometric field examinations of measured stratigraphic 

sections are as follows:

Wise formation, Pennsylvanian age, Wise County, Va. Shale and sandy 

shale in 6 beds, ranging from 10 to 65 feet in thickness, contain an estimated 0.001 to 0.002 percent equivalent uranium.

Norton formation, Pennsylvanian age, Wise County, Va. Shale and 

sandy shale in 15 beds, ranging from 4 to 125 feet in thickness, contain an 

estimated 0.001 to 0.002 percent equivalent uranium.

Kanawha formation, Pennsylvanian age, McDoivell County, W. Va. Fossiliferous marine gray shale and sandy shale in 4 beds, ranging from 1 

to 30 feet in thickness, contain an estimated 0.003 percent equivalent 

uranium.

Price formation, Mississippian age, Pulaski County, Va. Shale and silty 

shale in 9 beds, ranging from 3 to 20 feet in thickness, contain an estimated 0.001 to 0.002 percent equivalent uranium. Siltstone in 1 bed, 

measuring 17 feet in thickness, contains an estimated 0.001 percent 

equivalent uranium.

All other shales and siltstones examined in the field or sampled and 

analyzed contain less than 0.001 percent equivalent uranium.
306 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

63 Snider, J. L., 1954, Reconnaissance for uranium in the Indiana coal field r 

U. S. Geol. Survey TEM-784, 26 p., issued by U. S. Atomic Energy 

Comm. Tech. Inf. Service Ext., Oak Ridge, Tenn.

A reconnaissance examination for radioactivity in coal and associated 

rocks was made in the Indiana coal field of southwestern Indiana. This 

field is a part of the Eastern Interior coal province which also includes 

areas in southern Illinois and western Kentucky. Sandstone, siltstone,. 

shale, limestone, clay, and coal were examined in the Mansfield, Brazil, 

Staunton, Linton, Petersburg, Dugger, and Shelburn formations, all of 

Pennsylvanian age. Most of the coal beds examined in Indiana contaia 

less than 0.001 percent uranium.

A marine black shale bed 1 foot' thick and just overlying coal No. V 

of the Petersburg formation in Pike County, Ind., contains as much as 

0.021 percent uranium; other marine black shales generally contain 0.005 

percent or less equivalent uranium.

Twenty-eight samples of shales of differing lithologic character were 

tested for uranium content in the laboratory. Of these, 20 "shale" samples contain an average of about 0.004 percent and a maximum of 0.01 

percent equivalent uranium, 8 "gray shale" samples contain an average 

of about 0.003 percent and a maximum of 0.004 percent equivalent uranium, and 20 "black shale" samples contain an average of about O.OOT 

percent and a maximum of 0.021 percent equivalent uranium. In addition, 10 siltstone samples and 1 mudstone sample contain less than 0.001 

percent equivalent uranium, and a pyrite nodule from a sample of black 

shale contains about 0.001 percent equivalent uranium.

The shale beds above the No. V coal (Petersburg formation) and 

Minshall coal (Minshall formation) contain in places an average of about 

0.006 percent equivalent uranium. "The radioactive shale was above 

the coal at all localities sampled * * * There appears to be a relationship between radioactivity and lithologic type of shale * * * rather than 

to position in relation to the underlying coal or overlying limestone. * * * 

The very dark gray shale containing abundant organic matter is more 

radioactive than the lighter colored shale containing less organic matter * * *." The shale with the greatest radioactivity is described as 

"grayish black to black, hard, very fissile when weathered, concoidal 

fracture when fresh, satiny luster, vitrain bands, few pyritic nodules."

"The fact that the radioactive matter was deposited contemporaneously 

with the shale is indicated by the wide areal extent of the radioactivity 

in a stratigraphically limited shale unit. The source of the radioactivity 

could be uranium in sea .water * * *." The vitrain stringers are indicative of plant material which "may have absorbed radioactive elements 

from the sea water. * * * The black shale above coal V is widespread 

in Indiana and adjacent States and the reserves of shale are large."

64 Stockdale, P. B., 1955, An investigation of the Chattanooga black shale 

of Tennessee as a source of uranium Progress report, Jan. 1, 1955, 

to June 31, 1955 (Univ. of Tenn.) : U. S. Atomic Energy Comm. 

ORO-143, 11 p., issued by U. S. Atomic Energy Comm. Tech. Inf. 

Service Ext, Oak Ridge, Tenn.

This is a progress report of a continuing project begun In November 

1951 at the University of Tennessee. The primary purpose of the project 

"is to obtain a complete geologic picture of the Chattanooga shale in the
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 307

outcrop area of the Eastern Highland Rim and Northern Highland Rim 

of Tennessee and in a small area of southern Kentucky, with special 

emphasis upon stratigraphic relationships * * *."

The Chattanooga shale lies beneath 15,000 square miles of the Highland Rim and the Cumberland Plateau in Tennessee. "Assuming an 

average thickness of 25 feet for the Chattanooga formation and an average grade of 0.0025 percent, the calculations show approximately 20,000,- 

000 tons of uranium."

"The best average uranium grade in the Chattanooga shale in Tennessee is in the Gassaway member and the most readily accessible shale 

in large amounts with shallowest overburden is on the Highland Rim." 

Preliminary reserve estimates of uranium in the Gassaway member of 

5 counties in the northern half of the Eastern Highland Rim indicate an 

average uranium content of 0.0057 percent, an average thickness of the 

Gassaway member of 15.8 feet, and total reserves of 1,810,000 tons of 

uranium.

 5 Strahl, E. O., Camilli, Elena, Short, N. M., Silverman, E. N., Weiser, L. A., 

Wright, H. D., and Bates, T. F., 1954, An investigation of the mineralogy, petrography, and paleobotany of uranium-bearing shales 

and lignites, Scope A Shales; Third annual report Period of Apr. 1, 

1953, to Mar. 31, 1954 (College of Mineral Industries, Pennsylvania 

State University) : U. S. Atomic Energy Comm. NYO-6060, 70 p., 

issued by U. S. Atomic Energy Comm. Tech. Inf. Service Ext., Oak 

Ridge, Tenn.

Continuing studies were made at Pennsylvania State University, on 

behalf of the U. S. Atomic Energy Commission, to find the nature of the 

uranium-bearing compound or compounds and their associations and the 

controlling factors of uranium deposition in uraniferous shales. Sixty 

samples selected from a drill core of 35 feet of Chattanooga shale from 

the Young's Bend area of the eastern Highland Rim of Tennessee were 

utilized in the studies. The perfection of laboratory methods has resulted in the development of several important techniques including the 

application of ozonization procedures to remove carbonaceous material 

from thin section.

Qualitative and quantitative mineralogical studies of the 60 drill-core 

samples have shown that the major constituents, in addition to organic 

matter, are quartz, illite, pyrite, kaolin, feldspar, mica, and chlorite. Accessory minerals include carbonates, zircon, tourmaline, and apatite. 

"Specific samples, however, show a great variation in mineral content."

A careful study of the 60 core samples "has yielded statistically significant correlations between the amount of uranium and some of the 

shale constituents." The correlation of the amount of uranium is positive with respect to the "blackness," or color of the sample; sulfur content; and associated carbon and pyrite content. The correlation of the 

amount of uranium is negative with respect to the content of feldspar, clay, 

and FesOz. Contrary to general belief, the black beds which contain more 

uranium are coarser grained than the gray beds.

Alpha-track studies of 13 thin sections show that significantly fewer 

tracks are associated with quartz plus feldspar whereas significantly 

more tracks are associated with opaques (mainly organic matter and 

pyrite).
308 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

"The data make it evident that the concentration of uranium in theChattanooga shale is not due to the presence of any one of the componentsstudied but rather to a combination."

66 Swanson, V. E., 1955, Uranium in carbonaceous rocks, black shale investigations, midcontinent Devonian shales, in Geologic investigations of 

radioactive deposits Semiannual progress report, Dec. 1, 1954, tO' 

May 31, 1955: U. S. Geol. Survey TEI^540, p. 169-170, issued by 

U. S. Atomic Energy Comm. Tech. Inf. Service Ext., Oak Ridge, Tenn. 

"An abnormally high-grade uraniferous black shale was found near 

Yellville, Marion County, Ark. Two select samples contain 0.12 and 

0.71 percent uranium, respectively. The black shale is confined to a lensless than 3 feet thick in the lower Mississippian basal sandstone member 

of the Boone formation and 'is lithologically similar to the Chattanooga 

shale of northern Arkansas. The shale having the highest radioactivity 

contains much coalified plant material. Although analytical data on additional samples collected are not yet available, the average uranium content 

of the shale in the lens is believed to be less than 0.02 percent uranium.'^

67 Swanson, V. E., 1956, Uranium in marine black shales of the United 

States: Internat. Conf. on Peaceful Uses of Atomic Energy, Geneva^ 

1955, Proc., v. 6, Geology of uranium and thorium, p. 430-434; U. S^ 

Geol. Survey Prof. Paper 300, p. 451-456.

Hundreds of black shale units, ranging in age from Precambrian toTertiary, have been examined in the search for uraniferous marine black 

shales in the United States. This examination has been undertaken for 

the most part, on a reconnaissance basis utilizing radiometric scanning 

methods with some sampling. The radioactivity of some subsurface shale 

units penetrated by oil and gas wells has been determined from gamma-ray 

well logs and cores. A few widespread shales contain on the order of 

0.007 percent uranium, but "with few exceptions, the uranium content 

of known marine black shales of the United States does not exceed 0.02 

percent, and the contents of few shale units having a thickness of more 

than 2 feet exceed 0.005 percent uranium." Although not currently being 

exploited, these vast deposits of low-grade uraniferous shale represent an 

extremely large reserve tonnage of uranium.

The uranium mineral or minerals in black shales have not been identified. "The uranium is apparently thoroughly disseminated in the shale but 

is associated most closely with the contained organic matter" and was 

presumably adsorbed from solution by this organic material.

In general, significantly uraniferous marine black shales contain (a) 

abundant organic matter with some oil content; (b) pyrite in the form 

of lenses, nodules, and minute crystals; (c) phosphate as nodules or 

disseminated particles; and (d) abnormal amounts of trace elements, 

such as copper, nickel, vanadium, germanium, and molybdenum. The 

uranium content generally decreases sharply with small increases of calcium carbonate. Many marine black shales are virtually nonuraniferous 

even though they are lithologieally similar to the more uraniferous marine 

black shales.

Chattanooga Shale

The Chattanooga shale, of Devonian and Mississippian age, is the 

largest low grade reserve of uraniferous black shale in the United States.
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 309

It crops out in central Tennessee and adjacent parts of Alabama and 

Kentucky, is generally less than 35 feet thick, and contains from 0.001 

to 0.035 percent uranium. It consists mostly of black siliceous shale and 

gray claystone, with a few thin sandstone beds, calcareous lenses, chert 

layers, and phosphatic nodules. The black shale units of the Chattanooga 

are composed of about 35 percent clay, feldspar and mica; about 25 percent silt-sized quartz grains; about 20 percent organic matter; about 15 

percent pyrite, and minor amounts of chlorite, phosphate, calcite, and 

heavy minerals.

"Correlatives of the Chattanooga shale, all slightly radioactive, are 

the New Albany shale of Illinois, Indiana, and Kentucky, the Antrim 

shale of Michigan, the Sunbury and Ohio shales of Ohio and Kentucky; 

the Genesee group, Dunkirk member of the Perrysburg formation and 

other thin shales of New York, the Chattanooga shale of Kansas, northern. 

Arkansas, and northern Oklahoma, and the Woodford chert of Oklahoma 

and Texas. The Chattanooga shale and its correlatives accumulated in a 

widespread relatively shallow epicontinental sea * * *" where an extremely slow accumulation of mineral detrital material and a relatively 

high accumulation of carbonaceous debris took place.

Pennsylvanian Shales, Midcontinent Region

About 2,500 feet of rocks of Pennsylvanian age are exposed in eastern 

Kansas and nearby parts of Oklahoma and Missouri. Marine black shale 

beds, generally only a few feet thick, are scattered throughout the sequence. Many of these beds are units of cyclic deposition that include 

layers of sandstone, coal and limestone. About 20 of the black shale 

units in this sequence are abnormally uraniferous and contain more than 

0.003 percent uranium.

"Many of these black shales of Pennsylvanian age are characterized by 

irregularly distributed small phosphatic concretions or nodules * * V 

These nodules may contain as much as 0.10 percent uranium with an 

average of 0.015 to 0.020 percent uranium and are generally more radioactive than the enclosing shales. No correlation has been found between 

uranium content and (a) the abundance of these nodules in the shales, 

(b) the thickness of the shale beds, or (c) the lithologic character of 

the shales.

These thin black shale units of Pennsylvanian age were apparently 

deposited in an extremely shallow sea with a bottom reducing environment and accumulation of abundant organic debris. The uranium 

in solution "was adsorbed in this bottom sludge, with a preferential chemical exchange bonding the uranium and the phosphate during the accretionary growth of the nodules."

Phosphoria Formation

Two black pyritic and phosphatic shale members of the Phosphoria 

formation of Permian age, exposed in southwestern Montana, eastern 

Idaho, and adjacent parts of Wyoming and Utah, contain as much as 

30 to 38 percent P2O6 and from 0.010 to 0.033 percent uranium. A positive 

correlation exists between the uranium content and the abundance of 

phosphatic and carbonaceous matter, and apparently these constituents 

contain the uranium. "The Phosphoria formation may be roughly divided 

into a miogeosynclinal facies on the west and a platform facies on the
310 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

east." A genetic similarity to the other uraniferous black shales described 

is suggested, though it is probable that the sediments accumulated in the 

Phosphoria sea at a more rapid rate.

Other Uraniferous Shales

Other uraniferous marine black shales in the United States include 

thin black shale beds of Mississippian age in Montana and Utah, phosphatic black shale in the Barnett formation of Mississippian age in central 

Texas, parts of the Heath shale of Mississippian age in central Montana, 

black shale units in the Hermosa formation of Pennsylvanian age in 

western Colorado, and pyritic and carbonaceous shale in the Sharon 

Springs member of the Pierre shale of Late Cretaceous age in southern 

South Dakota, northeastern Colorado, and adjacent parts of Nebraska 

and Kansas.

Geologic Significance

Although marine carbonaceous shales accumulated in miogeosynclinal 

and eugeosynclinal areas, the general tectonic and paleogeographic category into which most uraniferous shales fall is that of the epicontinental 

area. This environment was common to much of the interior of the 

United States during several intervals of the Paleozoic. The long-term 

inundation of a broad expanse of a relatively flat surface and the lack 

of a source of a large amount of clastic sediment made possible the development of specific geochemical conditions that controlled the accumulation and preservation of uraniferous carbonaceous muds.

68 Thompson, M. E., 1953, Distribution of uranium in rich phosphate beds of 

the Phosphoria formation: U. S. Geol. Survey Bull. 988-D, p. 45-67.

Five sets of "close" samples [of phosphate-rich beds from the Phosphoria 

formation] were analyzed radiometrically for uranium and chemically for 

P2O6, CaO, organic matter, and loss on ignition. A Rosiwal analysis was 

made of thin sections of one set of samples. The results of the analyses 

have been plotted on graphs and on scatter diagrams, and coefficients of 

correlation are given for uranium with CaO, P2O5, organic matter, and loss 

on ignition. Preliminary studies indicate that the concentration of uranium in these samples of phosphate rock is not due wholly to phosphate 

content but may depend in part on organic matter or on other components. 

The correlations of uranium with P2O5 are poor in the groups of samples 

with smaller amounts of uranium but are good in the groups of samples 

containing more uranium. Author's abstract

The samples contain from 0.004 to 0.065 percent equivalent uranium, 

from 1 to 36 percent phosphate, and from 1 to 12 percent organic matter.

69 Tourtelot, H. A., 1956, Radioactivity and uranium content of some Cretaceous shales, central Great Plains: Am. Assoc. Petroleum Geologists 

Bull., v. 40, p. 62-83.

The Sharon Springs member of the Pierre shale of Late Cretaceous age, 

a hard black organic-rich shale, similar in many characteristics to the 

Chattanooga shale, is radioactive throughout central and western South 

Dakota, most of Nebraska, northern Kansas, and northeastern Colorado.
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 311

In the Missouri River valley, thin beds of the shale contain as much as 

0.01 percent uranium. Beds correlated with the Sharon Springs are as 

much as 20 feet thick or more and have a radioactivity of about 0.01 percent equivalent uranium in southwestern Nebraska, according to interpretation of gamma-ray well logs. The radioactivity and uranium content 

are highest in the Missouri River valley in South Dakota and in southwestern Nebraska where the shale rests disconformably on the underlying 

Niobrara formation, also of Cretaceous age. Near the Black Hills, and 

in the area on the north, the shale of the Sharon Springs member rests on 

a wedge of the Gammon ferruginous member of the Pierre, which is represented by a disconformity on the east and south, and the radioactivity 

of the shale is low, although greater than that of overlying strata. The 

shale also contains a suite of trace elements in which arsenic, boron, 

chromium, copper, molybdenum, nickel, selenium, and vanadium are conspicuous. Molybdenum and tin are less abundant in the Sharon Springs 

than in similar shales of Paleozoic age, and silver and selenium are more 

abundant.

Uranium determinations and semiquantitative spectrographic analyses 

are shown in tabular form and include analyses of samples of Big Stone 

Gap shale of Devonian and Mississippian age from Wise County, southwestern Virginia, 0.004 percent uranium; shale of Devonian age from 

Burnet County, central Texas, 0.01 percent uranium; and Chattanooga 

shale of Devonian and Mississippian age from Tennessee, 0.003 to 0.008 

percent uranium.

In the Great Plains region, the upper 30-50 feet of Cretaceous shales 

overlain unconformably by the White River group of Oligocene age have 

been altered by pre-Oligocene weathering and later groundwater conditions 

to a brightly colored zone. This altered zone in the Niobrara formation 

has masses of unaltered shale in its lower part that contain as much as 

0.1 percent equivalent uranium and 0.03 percent uranium. This uranium 

is believed to have been derived from the overlying White River group. 

From author's abstract

70 Twenhofel, W. S., Finch, W. I., Osterwald, F. W., Bell, K. G., and Stead, 

F. W., 1954, Resource studies, in Geologic investigations of radioactive 

deposits Semiannual progress report, June 1 to Nov. 30, 1954: U. S. 

Geol. Survey TEI^90, p. 298-299, issued by U. S. Atomic Energy 

Comm. Tech. Inf. Service Ext., Oak Ridge, Tenn.

Preliminary analytical data indicate that the natural radioactivity of 

rocks at the surface of the earth varies widely from a few parts per 

million to possibly 50 parts per million of equivalent uranium. The 

authors state:

Further analysis of the data should clarify the expectable "normal" variation in radioactivity for a few limited environments such as the Mancos 

shale, which ranges from 6 parts per million to 40 parts per million of 

equivalent uranium where the total radioactivity of 40 parts per million 

consists of 20 parts per million caused by the uranium series of elements 

and 20 parts per miUion caused by the potassium series of elements.

It is now apparent that a rather significant variation in the total radioactivity of some shales can be attributed to variation in [radioactive] potassium content with no change in uranium content. These studies are being 

continued.
312 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

71 Weaver, Paul, 1942, A theory of the distribution of radioactivity in marine 

sedimentary rocks: Geophysics, v. 7, p. 192-198.

The relative gamma-ray intensity of muds, clays, and shales is usually 

the highest of any of the sediments, as determined by gamma-ray 

logs of wells. According to recent estimates, the rate of sedimentation 

for marine shales is about 1 foot per 900 years (thickness after compaction). Thus, the gamma-ray measurements of marine sedimentary 

rocks indicate that in general the amount of radioactivity in marine 

sediments varies inversely with the rate of sedimentation.

"The most recent measurements of the radioactivity of sea water suggest 

an increase with depth, which indicates a very slow settling rate of 

small particles." The possible sources of these mineral particles are 

(a) fine river muds, (b) volcanic dust from eruptions, (c) meteor clouds, 

and (d) general dust circulated by large wind movements. Of these 

sources, only the last is considered to have the necessary attributes to 

account for a widespread and uniform deposit of relatively high radioactivity.

72 Wedow, Helmuth, Jr., 1954, Reconnaissance for radioactive deposits in 

the Eagle-Nation area, east-central Alaska, 1948: U. S. Geol. Survey 

Circ. 316, 9 p.

"Reconnaissance of radioactive deposits in sedimentary rocks of 

Proterozoic and Paleozoic age, and granite of Mesozoic(?) age together 

with its Tertiary sedimentary derivatives, was conducted in 1948 in the 

Eagle-Nation area, east-central Alaska. None of the rocks examined 

contains more than 0.003 percent equivalent uranium except for black 

shale beds in the Calico Bluff formation of Late Mississippian age and 

in granite of Mesozoic(?) age and its sedimentary derivatives. The 

more radioactive black shale beds in the Calico Bluff formation range 

in thickness from % to 7 feet. Two units near the base of the formation 

appear to be persistent in the area: Radioactive unit A, with an average 

thickness of G.6 feet, which contains an average of 0.007 percent equivalent 

uranium and 0.004 percent uranium, and radioactive unit B, with an 

average thickness of 5.2 feet, which contains an average of 0.006 percent 

equivalent uranium and 0.003 percent uranium. Phosphatic pellets from 

unit B at one locality contain 0.022 percent equivalent uranium, 0.019 

percent uranium, and 15 percent P2O5." The maximum uranium content 

of the black shale in the 2 units is 0.006 percent. Although marine black 

shales of Cambrian, Ordovician( ?), Devonian, Early (?) Mississippian, 

Permian, and Triassic age are the most radioactive in the rock sequences 

that were traversed, they contain 0.003 percent or less equivalent uranium.

73 Wedow, Helmuth, Jr., White, M. G., and Moxham, R. M., 1951, Interim 

report on an appraisal of the uranium possibilities of Alaska: U. S. 

Geol. Survey TEM-235, 124 p. (open-file report). See p. 11, 98, 101, 

106, and 113.

Summaries of the geology and mineral deposits, and appraisals of the 

uranium possibilities of the various regions of Alaska are presented in 

this preliminary report. A short statement of previous knowledge and 

investigations of radioactive materials in the Territory also is given.
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 313

During the reconnaissance investigations, outcroppings of various rocks, 

including sedimentary formations, were tested for radioactivity. A summary of those shales containing uranium of probable syngenetic origin 

is given below.

Northern Alaska

The uraniferous oolitic phosphate and phosphatic shales in the Lisburne 

group of Mississippian age along the north flank of the Brooks Range 

are the only uraniferous sedimentary rocks known in northern Alaska. 

Random samples from a phosphatic unit, which is similar in appearance 

and composition to the bedded phosphates of the Phosphoria formation 

in northwestern United States, average 31.95 percent PaOs and 0.013 

percent uranium.

Porcupine District

Radiometric traverses were made over thick sequences of sedimentary 

rocks of Precambrian and Paleozoic age and associated intrusive rocks 

in the Porcupine district, which is in the northeastern part of the Upper 

Yukon region of east-central Alaska. The black shales of Silurian, 

Devonian, and Mississippian age, which were among the most radioactive 

rocks traversed, contain not more than 0.005 percent equivalent uranium.

Tolovana District

In the Tolovana district, which lies northwest of Fairbanks in eastcentral Alaska, black shales of Mississippian age were found to contain 

not more than 0.002 percent equivalent uranium.

Eagle District

Black shale beds near the base of the Calico Bluff formation of Mississippian age in the Eagle district of the upper Yukon River contain between 

0.005 and 0.01 percent equivalent uranium. Phosphatic pellets and nodules 

that are scattered through some of these radioactive black shale beds, 

contain as much as 0.02 percent equivalent uranium.

74 Wedow, Helmuth, Jr., White, M. G., Stevens, J. M., and Tolbert, G. E., 

1954, Reconnaissance for radioactive deposits in east-central Alaska, 

1949: U. S. Geol. Survey Circ. 335, 22 p. See p. 1-3.

Chapter A is concerned with the Fairbanks and Livengood quadrangles in east-central Alaska. In 1949, several mines and prospects in 

these quadrangles were examined for radioactivity. Metamorphic and 

sedimentary rocks of Precambrian and Paleozoic age were examined for 

radioactivity along the Elliott Highway.

The greatest radioactivity found in the rocks along the Elliott Highway was in an iron-stained Precambrian schist and in a carbonaceous (?) 

shale of Middle Devonian or Mississippian and Pennsylvanian age. 

Samples of these rocks contain 0.003 and 0.004 percent equivalent uranium, respectively.

Subsequent chapters contain no information on radioactivity of possible syngenetic origin in marine black shales or phyllites.
314 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

75 Welch, S. W., 1953, Radioactivity of coal and associated rocks in the 

anthracite fields of eastern Pennsylvania: U. S. Geol. Survey TEI348, 31 p., issued by U. S. Atomic Energy Comm. Tech. Inf. Service 

Ext., Oak Ridge, Tenn.

In 1953 a reconnaissance study was made of the radioactivity in the 

anthracite coal fields of eastern Pennsylvania. Selected coal beds and 

associated rocks were examined in the Pottsville, Allegheny, and Conemaugh formations of Pennsylvanian age from each of the four major 

coal fields: (a) the Southern, (b) the Eastern Middle, (c) the Western 

Middle, and (d) the Northern. Forty-six localities were visited and 150 

coal and 3 shale samples were collected. The radioactivity of the coal, 

siltstone, and claystone is estimated as 0.001 or less percent equivalent 

uranium, and the shale contains from about 0.001 to 0.003 percent equivalent uranium.

Most of the shale is described as dark gray and carbonaceous. The 

shale beds range in thickness from 1 inch to 10 feet, most of them being 

4 feet or less in thickness. In Schuylkill County in the Southern field 

a bed of medium light-gray shale 2 feet in thickness from the Allegheny (?) formation contains about 0.003 percent equivalent uranium.

The author concludes that the uranium content of the rocks in the 

anthracite fields of eastern Pennsylvania is "too low to be of economic 

interest at the present time."

76 Welch, S. W., 1953, Radioactivity of coal and associated rock in the coal 

fields of eastern Kentucky and southern West Virginia: U. S. Geol. 

Survey TEI-347A, 38 p., issued by U. S. Atomic Energy Comm. Tech. 

Inf. Service Ext., Oak Ridge, Tenn.

In 1952 a reconnaissance was made of the radioactivity of the coals 

and associated rocks of eastern Kentucky and Logan and Mingo Counties, 

W. Va. The coal-bearing beds of this region are in the Lee and Breathitt 

formations of Pennsylvanian age. Most of the radioactivity measurements were made from samples from operating coal mines and consisted 

chiefly of coal, with some samples of shale, siltstone, limestone, sandstone, underclay, and flint fire clay. Two samples of intrusive dike rock 

also were tested. The radiometric tests showed the coal to have little 

or no radioactivity: 0.000 to 0.001 percent estimated equivalent uranium. 

The other rocks sampled were slightly radioactive and contained about 

0.002 percent estimated equivalent uranium.

Shales were examined and tested at 59 out of the 61 localities visited. 

Only 3 out of 132 shale samples tested contain as much as 0.002 percent 

equivalent uranium. These 3 shale samples were taken from Breathitt, 

Knott, and Perry Counties in Kentucky. They are predominantly dark 

gray and carbonaceous and two of them contain marine fossils. The 

shale beds range in thickness from 1 to 10 feet at the localities sampled.

At 4 localities, 7 siltstone beds were tested, but all contain less than 

0.001 percent estimated equivalent uranium.

"No correlation between radioactivity and stratigraphic position nor 

between radioactivity and structural relationship was detected."
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 315

77 White, M. G., 1952, Reconnaissance for radioactive deposits along the 

upper Porcupine and lower Coleen Rivers, northeastern Alaska: U. S. 

Geol. Survey Circ. 185,13 p.

A reconnaissance search for radioactive deposits was undertaken in 

1948 in northeastern Alaska.

"The highest equivalent uranium content found in the sedimentary rocks 

on the upper Porcupine River, northeastern Alaska, is 0.005 percent." 

Black shale and black slate in the Tindir group of Precambrian and 

Early Cambrian (?) age contain from 0.001 to 0.004 percent equivalent 

uranium. Black shale of Silurian age contains the highest amount of 

radioactivity and included a range of 0.001 to 0.005 percent equivalent 

uranium. Black shales of Devonian age are virtually nonradioactive 

and samples contain no more than 0.002 percent equivalent uranium. 

The black shales of Mississippian and Pennsylvanian age contain from 

0.001 to 0.003 percent equivalent uranium.

Although black shales have the highest radioactivity of the rocks tested 

along the lower Coleen River, none of these rocks (of Devonian or 

Mississippian and Pennsylvanian? age) contains more than 0.003 percent 

equivalent uranium.

78 White, M. G., and Killeen, P. L., 1953, Reconnaissance for radioactive 

deposits in the lower Yukon-Kuskokwim Highlands region, Alaska, 

1947: U. S. Geol. Survey Circ. 255,18 p. See p. 1 and 9.

Investigations in the region between the lower Yukon and Kuskokwim 

Rivers in western Alaska reveal that the only abnormal radioactivity in 

the vicinity of Flat is due to uraniferous zircon, an accessory mineral in 

monzonite.

The sedimentary rock sequence in the Flat area, consisting of gray and 

black shales interbedded with sandy shale and sandstone of Late Cretaceous age, was tested in the field for radioactivity but results were 

negative. "Particular emphasis was placed on outcroppings of black shale 

in an attempt to locate any bed that might contain a significant quantity 

of radioactive material. Samples from three different localities that gave 

the highest radiometric readings in the field contain only 0.002 percent 

equivalent uranium."

79 Whitehead, W. L., 1950, Studies of the effect of radioactivity in the transformation of marine organic materials into petroleum hydrocarbons, 

Research Project 43c, in Report of progress Fundamental research 

on occurrence and recovery of petroleum, 1948-1949: New York, Am. 

Petroleum Inst, p. 226-229.

This is a biennial report on the progress of continuing research conducted 

by the Massachusetts Institute of Technology for the American Petroleum 

Institute concerning the quantitative evaluation of the amount of crude 

oil formed by the effects of radioactivity on marine organic substances. 

The studies include research on (a) the yield factor for reactions producing hydrocarbons, (b) the loss of radioactive energy through absorption 

in the sediments, and (c) the content and mode of occurrence of radioactive elements in organic marine sediments and sedimentary rocks.
316 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

Radioactivity determinations of fractions of powdered organic shales 

indicate that the finest size organic fractions may be more radioactive 

than the more argillaceous fractions. Measurements of the potassium 

content and the radioactivity of 10 formations were made by using a 

flame photometer, and by alpha-particle and net beta counts. The rocks 

studied are from 10 sedimentary formations of marine origin. Of these, 

there are 3 from east Texas: the Woodbine formation, the Eagle Ford 

shale, and the Austin chalk; 3 from southern Mississippi: the Tuscaloosa 

and the Eutaw formations and the Selma chalk; 2 from Oklahoma: the 

Cherokee shale (former usage) and the Chattanooga shale; the Woodford 

shale from western Texas and the Miocene nodular shale from the Los 

Angeles Basin of California.

Graphs indicate the frequency distribution of total and net beta counts 

and the potassium content for the Eagle Ford shale, the Woodbine sand, 

and the Tuscaloosa and Eutaw formations. These curves indicate a very 

low variation of radioactivity. A graph shows a slight increase in total 

beta emission with depth for oil well core samples of the Playa del Rey 

shale [probably Miocene nodular shale of this paper].

80. Whitehead, W. L., 1952 Studies of the effect of radioactivity in the transformation of marine organic materials into petroleum hydrocarbons, 

Research Project 43c, in Report of progress Fundamental research 

on occurrence and recovery of petroleum, 1950-1951: New York, Am. 

Petroleum lost., p. 192-201.

This is a biennial report on the progress of continuing research conducted by the Massachusetts Institute of Technology for the American 

Petroleum Institute concerning the quantitative evaluation of the amount 

of crude oil formed by the effects of radioactivity on marine organic substances.

Analyses for potassium and organic carbon were made on several organic 

marine sedimentary rocks (see reference 79). Tables and graphs that 

show the results of these determinations plus total and net beta counts 

are included. It was found that the net beta activity increased with 

an increase of potassium for all the formations tested except the Miocene 

nodular shale of southern California. The Antrim shale of Michigan was 

shown to have the highest median content of potassium (2.77 percent).

Excellent correlation between organic carbon content and radioactivity 

suggests that a genetic relationship exists between the two. An increase 

in radioactivity with an increase in the phosphorus content (as nodules 

of calcium phosphate) is noted for the Miocene nodular shale and the 

Cherokee shale (former usage) of Oklahoma.

The apparent linear relationship between the carbon and phosphate 

content of the Miocene nodular shale suggests a common genetic factor in 

the environment of accumulation. The phosphorus in ancient seas indirectly may have been responsible for the abundant organic matter as 

well as the precipitation of uranium. The organic matter, when precipitated as colloids, also may have taken some of the uranium out of 

solution.

Studies of the "tracks" that alpha particles make on photographic film 

were made of the Cherokee, the Miocene nodular shale, the Woodford 

shale of Oklahoma, and the Woodford shale of Texas. The results are 

given in tabular form and two photomicrographs of "tracks" from the
URANIUM-BEARING MARINE BLACK SHALES IN UNITED STATES 317

first two named shales are included. A ratio of the number of alpha particles originating in inorganic material to the number originating in organic material in the thin sections of the shales tested is 2.4 to 1.

81 Whitehead, W. L., 1954, Hydrocarbons formed by the effects of radioactivity and their role in the origin of petroleum, in Faul, Henry, ed., 

Nuclear geology: New York, John Wiley & Sons, Inc., p. 195-218.

Previous studies conducted by the Massachusetts Institute of Technology, for the American Petroleum Institute, into the origin of petroleum 

through the bombardment of certain organic substances and their related 

compounds, are reviewed.

The average total radioactivity of 8 composite samples of sedimentary 

formations (including 5 shales) is about 4X10"12 grams of equivalent 

radium per gram of sediment. It was proved that a negligible amount of 

hydrocarbons are formed by the effects of radioactive bombardment, but 

this cannot account for the great bulk of the oil to be found in the sediments.

The review includes tables and figures that show the relation of radioactivity to the carbon, potassium, and phosphorus content of several sedimentary formations, including the Antrim shale of Michigan, the Woodford shale of western Texas, the Cherokee shale (former usage) of Oklahoma, the Eagle Ford shale of eastern Texas, and the Miocene nodular 

shale of southern California. An excellent correlation between radioactivity on the one hand, and phosphorus and organic carbon content, on 

the other, was established for the Miocene nodular shale and Cherokee 

shale. The radioactivity was shown to increase with an increase of potassium content for all the formations studied, with the exception of 

the Miocene nodular shale.

INDEXES

AUTHORS

Alexander, F. M.

Reference

No. 

..... 1

Bachman, G. O...._______________ 2 

Bain, G. W.................................. 3

Bates, T. F........_..............._...... 4,65

Beers, B. F._____________..____ 5,6 

Bell, K. G...__- .____..______._._ _.__ 7,8,70

Beroni, E. P.____.______________ 9,33 

Bradley, W. H.__._._..._._........ 10

Branson, C. C__________________ 11 

Breger, I. A...._._..__....._.. 12,13,14,23

Brown, Andrew_________________ 15 

Brown, J. H., Jr.________________ 16 

Burbank, W. S______._________.. 17 

Burton, V. L................_._.......... 18

Burwell, A. L______._____._____ 11 

Butler, A. P., Jr...................._....... 19,20

Camilli, Elena.......______________ 4,65

Carswell, L. D__________________ 39

Chase, G. S......___._.__.._...._ 11

Conant, L. C.___.__,___________ 21

Deul, Maurice________________ 13,22,23 

Duncan, D. C_______.________ 24 

Dunham, B. J__________________ 25

Eargle, D. H.____________._____ 26 

Evans, B. D___________________ 27 

Everhart, D. L__...........__.......... 28,40

Ferm, J. C...__. 

Finch, W. I..__. 

Fredrickson, A. F.

Garrels, B. M......._____._____..... 40

Glover, Lynn..-.________________ 31 

Goodman, Clark________________ 6,8,27 

Gott, G. B...__.___._.............._ 32,33

Hill, J. W_.___._...._____......_ 32

Holland, H. D....._____._.__...._ 34

Hopkins, M. E__________________ 48

Huddle, J. W................................ 35

Keller, W. D..___.___.___.____.. 16

Kepferle, B. C_.______________ 36

Killeen, P. L................................. 78

Krumbein, W. C________________ 37

Kulp, J. L____________________ 34

Kulstad, E. O...._________._....__ 55

McDuflee, Clinton______________ 55 

McKelvey, V. E...___________ 38,39,40,41 

McKeown, F. A....._________..._ 9,42,45

Reference

No. 

McVicker, L. D..........................._ 48

Mapel, W. J.................................. 43

Mathez, Muriel_________________ 28 

Moxham, R. M..________________ 44,72

Narten, P. F...._........._.............. 45,46

Nelson, A. E____._.________.___ 44 

Nelson,!. M...__.........__.._....... 41,46

Nininger, B. D..___...................... 47

Osterwald, F. W. 

Ostrom, M. E_.

Patterson, E. D.______________ 35,49,50 

Pepper, J. F________________.__ 51 

Pierson, C. T................._.....__.... 17

Bankama, Kalervo.... __ 52 

Bead, C. B_______________ 2 

Boss, V. F................................... 53

Buch, J. W ...._._....__.__....... 54

Bunnells, R. T.._...............__...._ 55,56

RusseU, W. L___._______.______ 57,58

Sahama, T. G_____.____ 52 

Schleicher, J. A......_...___.........._ 55,56

Scnnabel, B. W._ __._......._.__ 20,59

Schopf, J. M................................. 14,60

Short, N. M.._._._____._..______.___....._-_. 4,65

Silverman, E. N_.____________ 4,65 

Slack, H. A.......___..__..__.._.. 37

Snider,!. L........._____..____._ 61,62,63

Stead, F. W. ._._._._.__........ 70

Stevens, J. M_._____________ 74 

Stockdale, P. B_...................... .... 64

Strahl, E. O.................................. 4,65

Sullivan, G. B__________________ 18 

Swanson, V. E.......................... .. 66,67

Thompson, M. E. 

Tolbert, G. E__, 

Tourtelot; H. A... 

Twenhofel, W. S_.

73

70

Van Nortwick, H. S____._.___...... 56

Weaver, Paul..... 71

Wedow, Helmuth, Jr... ................ 72,73,74

Weiser, L. A............_...._._____ 65

Welch, S. W..... ....____________ 75,76

White, M. G...._.._.____..__ 73,74,77,78

White, W. A.....................____...-. 48

Whitehead, W. L....................... 8,79,80,81

Wright, H. D.-..__.__._._______ 65 

Wyant, D. G____._______ 33

319
320 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

GEOGRAPHIC AREAS

Reference 

No.

Alabama- ___________. 15,20,21,28,31,47,67 

Alaska:

General---- 10,19,28,41,47,73

Brooks Range._______________ 19,73 

Coleen River, lower..__________ 77 

Eagle district.____.__....__...._ 73

Eagle-Nation area______________ 72 

Elliott Highway 74

Fairbanks area. __________ _ __ 74 

Flat area.___._____....______ 78

Kuskokwim River area__________ 78

Livengood area._______________ 74

Matanuska Valley____________ 44

Nome.-__________________ 41

Porcupine River.._____________ 73,77

Richardson Highway___________ 44

Tolovana district______________ 73

Wrangell Mountains..._________. 44

Yukon River_______________ 19,73,78

Algeria-_.______________.____ 41,47

Arizona.._____________________ 2,24

Arkansas..._ _______________ 66,67

California: Los Angeles Basin, southern California.... .._.... 12,18,38,79,80,81 

Colorado:

General-... 2,24,67,69

Dolores County..______________ 17

Gunnison County______________ 17

Lake County..______________ 24

Ouray County....____________ 17,24

Red Mountain district...______ 17

Uncompahgre district..________ 17

Routt County, Steamboat Springs-..._ 9

San Juan County, Red Mountain district. 17

San Miguel County..__________ 17

Connecticut___________________ 42

Egypt ___._________________ 47 

England._____________________ 47 

Estonia....__ .... .__.... 10,28,41,47

Florida ___ 10,41,47,54

Georgia.... ____.___...._ 21,31,47

Idaho....__ _______.... 24,39,41,43,47,67

niinois:

General.. __.... 3,35,37,47,48,50,57,67

Gallatin County______________ 50 

Jefferson County._____________ 50 

Perry County_______________ 50 

Randolph County._____________ 50 

St. Glair County..______.__...... 50

Saline County________________ 50 

Union County________________ 48 

Williamson County_____________ 50

Indiana:

General-....._._____.__ 3,28,35,47,67

Indiana coal field_____________ 63 

Pike County......______._.. .. 35,63

Vermillion County.___________ 35

Reference

No.

Ind iana Continued

Vigo County...____________.... 35 

Warrick County....._ ... 35

Kansas:

General.. 7,10,20,28,32,33,38,41,47,55,56,67,69 

Butler County...._... . 32 

Cowley County.______ 32 

Greenwood County.... 32 

Marion County..______ . 32 

Sedgwick County.... . 32 

Wyandotte County...___ 56

Kentucky:

General- --. 20,21,28,47,57,64,67,76 

Breathitt County.. 76 

Knott County._______ 76 

Perry County_ 76

Maine:

General.-... 46 

Piscataquis County.. 46 

Somerset County 46

Michigan:

General..-.-__-___ 6,10,28,41,47,67,80,81 

Osceola County. 5,6,12

Mississippi - 12,18,79

Missouri:

General... _- ----- 67 

Ste. Genevieve County.._. 16,33,38

Montana:

General..... 24,39,43,47,67

Daniels County.. 43 

Fergus County. 43 

Gallatin County. 43 

McCone County. 43 

Musselshell County.. 43 

Roosevelt County 43

Morocco 47

Nebraska:

General.... 24,36,67,68

Dawes County.. 25 

Sheridan County 25

Nevada...- - - 24,39

New Hampshire 42

New Mexico:

General.. - - 2,24 

McKinley County - 23 

Mora County... 2 

Otero County... 2 

Sandoval County 2 

Socorro County 2

New York:

General... - 28,42,61,67

Adirondack Mountains__ 45 

Albany County 45 

Champlain Valley 46 

Columbia County 45 

Greene County.._ 45 

Hudson Highlands... 42 

Hudson Valley 46 

Saratoga County 46
INDEX 321

"Nigeria.___ 

"North DakotaReference

No.

..... 47

. - 43

 Ohio:

General-.-. . - . 28,47,61,67

Carroll County_______________ 61

Cuyahoga County_____________ 14

^~ Franklin County, Columbus. ______ 60

pt" Tuscarawas County___________-. 61

'Oklahoma:

General-.. .6, 7,10,11,18,20, 28,32,33,38, 41, 47,

53, 57, 58, 67, 79, 80, 81.

Pontotoc County, Fitts Pool_______ 8 

Seminole district-..____________. 6 

Tulsa County, Tulsa...--------_-_.. 57

Pennsylvania:

General...._________________ 35, 75 

Beaver County_______________ 29 

Clearfield County____.............__ 29

Jefferson County.___________ 29 

SchuylkiU County.. .. ....... 75

"Bhode Island___________________ 42 

Russia.. .......... 3,7,10,28,41,47

South Africa..._._______.__.__ 13,41,54

South Dakota:

General...______________ 36,43,67,69 

Shannon County_________ _____ 25

Sweden 3,7,10,13,28,38,40,41,47,52,53

Tennessee:

General- ..-1,4,14,15, 20, 21, 28, 31, 38, 40, 47,64,

65, 67, 69.

Cumberland Plateau. ___________ 64 

Davidson County____________. 14 

Highland Rim area.__ ..._..-.. 4,15,64,65

Texas:

General..... 8,12,18,26,53,67,69,79,80,81 

Brewster County.._____________ 26 

Burnet County __ . . __ 69

Reference 

No.

Texas Continued

Dallas County, Dallas __ _... 26

Hudspeth County. -_-_____... 26

Navarro County..... - 8,27

Starr County ..-_.___.__. 8,27

Terry County..---- - - - 26

Trinidad....--- --___-_-_ 57

Tunisia.____________________ 47

United States......... 3,10,19,28,33,38,41,47,54,59

Utah:

General--.. - . 2,24,39,43,47,67 

Cache County____.___ 43 

Rich County 43

Uinta Basin-----.--_.... . .. 9

Venezuela___ .-.. -. 57

Vermont:

General-___________________ 42,45 

Chittenden County, Milton area. 42 

Windham County, Brattleboro__ . 42 

Rutland County, Fairhaven 45

Virginia:

General.____.__._----------- 20,62

Lee County-.._ . 62 

Pulaski County___.__ . 62 

Wise County_________ . 62,69

West Virginia:

General....____ _- - 49,62 

Logan County 76 

McDowell County-..._ 62 

Marion County..-.... 49 

Mingo County._ . 76 

Wetzel County._______.__. 49

Wyoming:

General..... 9,20,24,33,38,39,40,41,43,47,54,67 

Carbon County .. 9 

Lincoln County..__________.... 9,23,24 

Sweetwater County. 9 

Teton County.. 24
322 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

STBATIGBAPHIC UNITS

Reference 

No.

Allegheny formation___________ 29,49,61,75 

Alum shale, Sweden. 3,7,10,13,28,38,40,41,47,52, 53 

Antrim shale._.._..._ 3, 5,6,7,10,12,47,67,80,81 

Arbuckle group_________________ 32 

Austin chalk..__________________ 79

Babrosco "carbon," South Africa_______ 13

Bakken formation_______________ 43

Bakoven shale .__.______.__._ 45

Barnett formation________________ 67

Belden shale___________________ 24

Berea sandstone _._._ __...._._ 5

Berkshire schist--_____._________ 48

Big Stone Gap shale_______________ 69

Bomoseen grit _________________ 45 

Bone Valley formation-..________ 10,38,41,47

Boone formation_________________ 66

Bourbon formation. _______________ 10

Brazer limestone_________________ 24,43

Brazil formation_________________ 63

Breathitt formation-..-____________ 76

Brereton shale. .._.__ __..__-... 37

Brush Creek coal of Conemaugh formation... 29

Calico Bluff formation. ____ 10,19,41,47, 71,73

Cambrian rocks-._______________ 32,42,45

Cambrian shale, in Alaska___________ 72,77

in Estonia__________________ 41

in Russia__________________ 3,7,41

in Sweden....... 3, 7,10,13, 28,38,40,41,47, 52,53

Canajoharie shale_______________ 45 

Carbondale formation-.____________ 50 

Carboniferous rocks. See MississippianPennsylvanian.

Carlile shale.._________._______.. 25 

Caseyville formation..._____________ 50 

Chattanooga shale:

General summary papers___.._-_ . 3,7,

10,19,20,28,33,38,40,41,47,59,67

Detailed studies and references..__ 1,4,

5, 6, 11, 14, 15, 21, 22, 23, 31, 32, 54, 57, 58,

60,64,65,66, 69, 79.

Checkerboard limestone-______.__ 7,10,11,57 

Cherokee shale. . . . 18,32,38,53,79,80,81 

Chinle formation____________._ . 22 

Cleveland member of the Ohio shale 14 

Cohn coal, shale above-..... .. 48

Coldwater shale___________..__ 5,6 

Colorado shale________________ 43 

Conemaugh formation_____._ _ 29,75 

Cretaceous and Eocene phosphates, North

Africa....._._...... ._.. 38,41

Cretaceous rocks.--.___... 2,g, 9,12,18, 22, 23,

24, 25, 26, 27,36,43,55,67,69, 70, 78, 79, 81

Cretaceous shale, Alaska.... 44,78

Dakota sandstone-....___...__ 22,23 

Davis coal, shale overlying..-_.__ 48 

Davis coal of the Tradewater formation,

shale overlying. 50 

Deepkill shale________ __ 45 

Del Rio clay of Grayson formation 26

Reference

No.

Devonian rocks_________________. 1,2, 

3, 4, 5, 6, 7, 9, 10, 11, 12, 14, 15, 19, 20, 21, 

22, 23, 26, 28, 31, 32, 33, 38, 40, 41, 45, 47, 

48, 51, 53, 54, 57, 58, 59, 60, 62, 64, 65, 66, 

67, 69, 72, 74, 77, 79, 80, 81.

Dictyonema shale, Estonia and Russia..___ 41 

Dowelltown member of Chattanooga shale... 15,21 

Dagger formation....____________.. 63 

Dunkard group..________________ 49 

Dunkirk member of Perrysburg formation__ 67 

Dunkirk shale__________________ 51

Eagle Ford clay (or shale).............. 18,26, 79,81

Ellsworth shale_________________ 5,6 

Eocene rocks. __________________ 9,54 

Escondido formation.-.____________ 26 

Esopus shale_. ______-___-___.. 45 

Eutaw formation________________ 18,79

Fort Scott limestone__-____-___.. 7,10 

Freeport coal of Allegheny formation _ ____ 29,49 

Frio clay.__ _---__--__-.__ -- 8

Gammon ferruginous member of Pierre shale. 69 

Gardner dolomite---_____________ 24 

Gassaway member of Chattanooga shale. 4,15,21,64 

Genesee group.--_ __-_________ 67 

Grayson formation.__ _. _. _-... 26 

Green River formation..... _...__.. 9, 54

Harrisburg No. 5 coal of Carbondale formamation, shale overlying-.. . 50 

Hartville formation....-.-__ --.-.-.-_.. 24,38,40

Heath shale...________________ 24,43,67 

Hermosa formation.....__---------__ 24,67

Herrin No. 6 coal of Carbondale formation .. 50 

Hudson River group..__.-__ _ 45 

Huron member of the Ohio shale.. ___. _ 60 

Hushpuckney shale.- _. .. 10

Tola limestone.. . ... 56 

Jurassic rocks. . 17,24

Kanawha formation. _. . 62 

Kansas City group... . .. 32 

Kennicott formation....__ - -------- 44

Kittanning coal, of Allegheny formation 29,61

Lake Valley limestone___ . 2

Lakota sandstone.. 24

Laney shale member of Green River formation. 9

Lee formation. 76

Leningrad shale, Estonia and Russia... .. 41

Linton formation 63

Lisburne group.....- 19,73

Lockatong formation... 22

McLeansboro formation 50 

Macoupin coal, shale above 48
INDEX 323

Reference 

No.

Madera formation 2 

Madison limestone..--- - 24,43 

Mancos shale.-..---- -------- . 9,70

Manning Canyon shale._.. . 24 

Mansfield formation- . - 63 

Maravillas chert-__-____.___ 26 

Marcellus shale.___-___--._, _.. - 45 

Marmaton group, - 11 

Martin limestone... - -. 2 

Matanuska formation.--___....__------- 44

Maury formation... 31 

Mesaverde formation..... .. 2

Milton dolomite 42 

Minnelusa sandstone. - 43 

Minshall formation_.-_.. - . 63 

Miocene nodular shale. -__ 12,18,38,53,79,80,81

See also Playa del Key shale. 

Miocene rocks.. - - 12,18,53,79,80,81

Mississippian and Pennsylvanian rocks - - 24,

38, 40, 74, 77 

Mississippian rocks.- ------- ------------ 2,5,6,

10, 11, 16, 24, 26, 28, 31, 38, 41, 43, 47, 53, 

59, 62,66,67,69, 72, 73,79, 80,81. 

Mississippian shale, Alaska___ 10,19,41,47,72,73 

Missouri series--.- - 11 

Monongahela series_-_ - 49,61 

Mountain Glen shale.--.- 48 

Muncie Creek shale member of Tola limestone, 56

New Albany shale .---_-_-------- 47,48,67

Niobrara formation-.- 25,69 

Nonesuch shale._______ __ 10,41,47 

Normanskill shale__ _ _ - 45 

Norton formation._____-__- - 62

No. 2 coal, shale overlying- __ 48,57 

No. 4 coal, shale overlying - _ 48 

No. 5 coal, shale overlying-. 35 

No. V coal of the Petersburg formation, shale

overlying-_ 63 

No. 6 coal, shale overlying__ ___ - 35,37,48

Ohioshale ------------_-_-__ 14,60,67

Oligocene rocks________________ 8,27,69 

Oologah limestone__-___ __ 57 

Oquirrh formation_-__ 24

Ordovician rocks.----- 8,24, 26,32,42,45,46,47, 57, 71

Ordovician schist, Russia._ __ - _ 3,7 

Orfordville formation._____________ 42

Paradox formation.-._____________ 24

Park City formation.______________ 24

Pennsylvanian rocks.--..._________ 2,3, 7

10, 11, 18, 19, 20, 24, 29, 32, 33, 35, 37, 38,

41, 43, 47, 48, 49, 50, 55, 56, 57, 61, 62, 63,

67, 75, 76.

Pepper shale member of Woodbine formation. 26 

Percha shale..._______________.. 2

Reference 

No.

Permian rocks_____________ __ - 9,10,

19, 22,23, 24,38,39,41,47,49, 59,67,68,73

Permian shale, Alaska_.__________ - 72

Perrysburg formation. .. _... - 67

Petersburg formation______ ________ 63

Phosphoria formation._____ ______ 9,10,

19,22,23,24,38,39,41,47, 59, 67, 68, 73

Pierre shale -------_ ... 25,36,43,67,69

Pittsburgh coal of Monongahela formation .. 49 

Playa del Rey shale_______________ S3,79

See also Miocene nodular shale. 

Pliocene rocks. ....._....._.... 10,38,41,47,57

Pony Express limestone member of Wanakah

formation_____ _______. 17,24

Pottsville formation_____________. 29,61,75

Precambrian rocks. 10,17,28,41,43,45,47,67,72,73,74

in Alaska__ __ ____ __ __ - ____ 74,77

in South Africa_____________ _ 13 

Price formation.___ __ ._._... 62

Bedstone coal of Monongahela formation...._

Rensselaergraywacke.--------------__ . 

Reynoldsburgcoal -----__ __-_....

49

45

48

Selma chalk___________________ 79 

Senora formation.____________.._. 11

Sharon Springs member of Pierre shale 25,36,67,69 

Shelburn formation____-_______ 63 

Shoal Creek limestone, shale underlying-. __ 48 

Silurian rocks .. ________________ 24,46 

Silurian schist, Russia..__._.___... 3,7 

Silurian shale, Alaska.---___________ 73,77 

Simpson group. -.____________..... 32

Snake Hill formation._._._.___-...- 45 

Spergen limestone [abandoned and replaced by

Salem limestone]. - _ ______ 16,33,38 

Stark shale____________________ 10 

Staunton formation___________-- 63

Stonefort limestone, shale overlying......._ 48

Sunbury shale.______________ 5,6,10,47,67 

Sylvan shale.___________________ 5,6

Tindir group. _______________-___ 77 

Tradewater formation_. ___ ___ __ _ 48,50 

Traverse formation.._______________ 5,6 

Triassicshale, Alaska----.________. 72 

Tuscaloosa formation______________ 79

Uncompahgre formation. 

Utica shale.--___--..

Wabaunsee group..-.- ---------____._ 32

"Wanakah formation.______________ 17,24 

Waynesburg coal of Washington formation _ 49 

Weber(?) quartzite..............._-. -__. 24

White River group, shales underlying....__ 69

Wise formation__________________ 62 

Woodbine formation....____________ 8,79

Woodford chert. - - 10,26,28,41,47,59,67 

Woodford shale ............... 5,6,11,53,79,80,81
324 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

SUBJECTS

Reference

No.

Alpha activity........_....._.......__ 5,12,79

Aluminum.___________________ 36

Analytical methods:

Potassium-40 ___ _____.____ 5,6 

Radium______________._____ 7,27 

Radon____________________ 7 

Thorium.._.______._____..... 5,6 

Uranium_________________ 5,6,16,27

Arsenic______________________ 36,69

Autoradiographic studies:

Chattanooga shale__._____.___ 4,15,65 

Other rocks.._________....__ 42,53,80

Beta activity.....__ __.______ 5,6,18,79,80

Black shales, generalized descriptions_____ 3,

7,10,11,19,20,28,38,40,41, 47,59,67

Boron._______________________ 36,69

Calcium........____......._.......... 40,56,67

Carbon content...................5,6,15,16,18,23,80

Cerium_____________________ 23 

Chromium.___________________ 69 

Copper.___... __ _______ 23,67,69

Equilibrium studies, radioactive_______ 12,43 

Fluorine______________________ 56

Gallium.............____.___........... 36

Geochemistry of uranium..._____ 13,16,30,40,52 

Germanium content..______________ 14,67

Hydrogen____._______________ 5,6,23 

Iron__ ......_.__ 36,52

Lanthanum . 

Lead_.....

Magnesium...._________________ 36

Mineralogy:

Chattanooga shale.. .. 4,15,21-23,65,67 

Phosphoriaformation.....________ 23,39 

Sharon Springs member of Pierre shale_ 36

Molybdenum.........___..... 23,36,40,52,67,69

Nickel.. .__..._._.... 14,23,40,52,67,69

Oil shales, uranium bearing_______ 9,10,32,55

Oil yield:

Chattanooga shale___._________ 1,54 

Other shales_._________.___ 3,54,55

Paleogeographic environment of accumulation:

Chattanooga shale.__............. 14,15,21,67

Other shales.__..._ 3,5,7,14,28,30,36,37,67 

Paleontology---.- ..._ .__._. 14,21,25,60 

Petroleum, origin................. 5,6,8,30,53,80,81

Phosphorites, generalized descriptions -.. _.. 7, 

10,19,38,41,47,59,67

Reference

No.

Phosphorus-_______________ 42,56,67,68 

Potassium -. -.. 5,6,18,52,79,80

Radium........ 5,8,12,27,32,43,57,81

Selenium_____________________ 36,39- 

Silver.---.. .___ .. .. 23 

Sodium______..._... ........... 36

Thorium.....--... 5,6,12,18,42,43 

Tin.... ._ _ __-_ .... 69 

Titanium.________________.___ 36

Uranium:

Relation between uranium andAluminum..____ .. 

Arsenic._ . 

Boron.._ 

Carbon (also "blackness") __

 36

..... 36 

..... 36

- 4,

5,10,15,16,18,23,30,57,65,67,80,81 

Carbonate-___--__.._ 38,39,41,51,67 

Calcium...... 38,57,67

Clay.-.. 4,16,30,37,65, 79

Copper._ 67 

Feldspar........ . ...- 4,65

Fluorine____________ _ 56 

Gallium..._.____ . .._-.. 36 

Germanium-.___.____... 14,67 

Iron oxide...._____._-___ 4,36,65

Magnesium-.-.__ ___ .. 36 

Molybdenum... .. 36,67 

Nickel.... - 67

Organic matter........ 6,10,13-16,18,22,23,

30,33,37,39,41,52,53,57,58,63,65-68,80 

Particle size. -..... 5,6,16,39,51,53,57,65,79

Phosphate__________-___ 10,

31,33,39,41,42,53,55, 56,67,68,72,80,81

Potassium .._...... 5,6,52, 70,80,81

Proximity of landmass to site of deposition..- . 12

Pyriteor iron sulflde-- -___-__--. 4, 

15,33,37,50,53,65,67

Quartz__._.__..__..-._ 4,65 

Rate of deposition_________ 34,57,71 

Selenium____________.. 36 

Sodium____ __.___..___ 36 

Stratigraphic position...-.-..-__ 15,63,76 

Structure.. 29,76

Sulfur (also "blackness'') -- 4,15,57,65 

Thorium-uranium ratio.. __. 5,6,12,18 

Titanium.......-... ..-. . 36

Vanadium-.. - -. 33,67 

Weathering ...... __.......... 29,39

Uranium, origin:

Marine black shales:

Chattanooga shale.______ - 14,15,21,65

Other. .. - 3,5, 7,8,13,14,17,30,

36-38,40, 41,47,52,53,58,63,67,69, 71,80

Other sedimentary rocks... .___ .._ 7, 

8,'2,17,34,42,48,69,71

Phosphorites. .......... ...... 7,38-41,67
INDEX 325

Reference

No.

Uranium content:

Marine black shales:

Chattanooga shale__________ 1,

3,7,14,21-23,28,32,33,38,54,64,67

Other................................ 2,

3, 7, 9, 12, 13, 16, 19, 20, 24-26, 28, 29, 32- 

38, 40, 41, 43-45, 47-51, 54-56, 58, 61-63, 

66,67,69,72-78. 

Other sedimentary rocks....______ 5,

6,9,12,23,25-27,29,32,42,63,69,70,75-77 

Phosphorites,........... 9,19,23,24,38,39,41,73

Slate, phyllite, schist, and argillite____ 3, 

7,17,42,44-46,74,77

Reference

No.

Uranium deposits in sedimentary rocks___ 3, 

7,10,19,20,28,33,38,40,41,47,59,67,69

Uranium reserves:

Black shales- ... .. -.. .. 3 

Black shales and slates of Russia____ 3 

Chattanooga shale....._ -.... 14,15

Vanadium .-.___. ._ . 3,14,23,40,52,67,69 

Yttrium. ... . . . 31 

Zinc ..___ .. 40