Selected Annotated 

Bibliography of the 

Geology of UraniumBearing Phosphorites 

in the United States

By DIANE CURTIS

SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

GEOLOGICAL SURVEY BULLETIN 1059-B

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 : 1957
UNITED STATES DEPARTMENT OF THE INTERIOR 

FRED A. SEATON, Secretary

GEOLOGICAL SURVEY 

Thomas B. Nolan, Director

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

Washington 25, D. C. - Price 20 cents (paper cover)
CONTENTS

Fag« 

Introduction._____________________________________________________ 29

Phosphate deposits._________________________________________ 29

Explanation of the bibliography and index maps __________________ 32

Acknowledgments _____________________________________________ 32

Selected annotated bibliography.__________________________ _ 32

Key to localities___-_______-_-__--_-___--_--__-__-_--_____---__--_- 35

Indexes

Authors,______-___-_-_--___----__-__-----_-_-_-_--__------_-_ 57

Geographic areas._____________________________________________ 57

General.-_-____-____________________________-____---- 58

ILLUSTKATIONS

Page

FIGURE 2. Index map of uranium-bearing phosphorites in the United

States -..________-_--____________-_-_-__ 34

3. Index map of uranium-bearing phosphorites in Alaska._ ___ 35

m

SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

SELECTED ANNOTATED BIBLIOGRAPHY OF THE 

GEOLOGY OF URANIUM-BEARING PHOSPHORITES IN 

THE UNITED STATES

By DIANE CURTIS

INTRODUCTION

The presence of uranium in phosphatic materials has been known 

since 1908 when Strutt a observed that phosphates have a higher radioactivity than most other rocks in the earth's crust. The fact was only 

of scientific interest, however, until World War II when uranium became important as a source of nuclear energy.

Although much work has been done on the geology of uraniumbearing phosphates, most of the reports are unpublished. This bibliography lists nearly all reports pertaining to uranium in domestic 

phosphorites that were available to the public as of December 1, 1955.

PHOSPHATE DEPOSITS

Phosphate deposits may be classified into 6 geologic types which 

are apatite deposits of igneous origin, residual deposits, phosphatized 

rock, river-pebble deposits, guano, and marine phosphorites.

Apatite is a constituent of many igneous and metamorphic rocks, 

but has been mined for phosphate in the United States only from the 

titanium-apatite deposits of Nelson County, Va. (ref. 22). So far as 

is known this rock has not been analyzed for uranium. According 

to Davidson (ref. 12, p. 26), the uranium content of samples of apatite 

from foreign countries ranges from less than 0.001 to 0.03 percent.

Residual deposits are formed by the concentration of phosphate 

derived from the weathering of marine phosphatic limestones. The 

brown phosphate rock deposits of Tennessee are an example of this

1 Strutt, Hon. R. J., 1908, On the accumulation of helium in geological time: Roy. Soc. 

London Proc., v. 81, ser. A, p. 272-277.

29
30 SELECTED BIBLIOGRAPHIES OF TJBANIUM GEOLOGY

concentration, but they are practically barren of uranium. The 

brown rock occurs along the northern and western edges of the central 

basin of Tennessee in the limestone outcrop belt of the Nashville 

group (of Safford, 1851 2 ) of the middle and upper parts of the 

Ordovician system.

Phosphatized rock is formed by the solution of phosphate from 

overlying rock and deposition, interstitially or through a replacement process, in underlying rocks (usually limestone). Examples of 

phosphate rock of this type are the white-rock deposits around the 

central basin of Tennessee and the belt of hard-rock deposits in the 

Alachua formation in northwestern Florida. The uranium content 

of these deposits is generally low.

River-pebble deposits (alluvial) occur as bars and banks in modern 

stream channels and in the adjoining lowlands. Deposits of this type 

in Florida and South Carolina were derived by the reworking of 

marine phosphorites. The uranium content of river pebble deposits 

is dependent upon and comparable with the uranium content of the 

material from which the pebbles were derived.

Guano, the excrement of birds and animals, has been deposited in 

the bat caves of Texas and New Mexico. The deposits are rich in 

phosphate but are too small to be an important commercial source of 

fertilizer. A few tons have been mined from the New Mexico deposits. 

As far as is known, guano contains practically no uranium.

Marine phosphorites are characteristically thin, but probably represent all the sediment deposited during long periods of geologic 

time. Phosphorites of this type are believed to be precipitated on 

shelving margins of large oceanic basins. All marine phosphorites 

that have been chemically analyzed contain from 0.005 to 0.03 per 

cent uranium.

The land-pebble deposits of Florida and the deposits in the western 

phosphate field are the principal source of phosphate in the United 

States.

The land-pebble district of Florida is in the west-central part of the 

peninsula. The phosphate deposits are mostly in the Bone Valley 

formation which is considered by most writers to be of Pliocene age. 

However, some of the phosphate mined is a residual part of the underlying Hawthorn formation of middle Miocene age. The high-grade 

phosphate is locally termed "matrix." Phosphate is mined only from 

the deposits in the northern half of the district, although there are 

some lower grade phosphate deposits in the southern half.

3 Safford, J. M., 1851, The Silurian Basin of middle Tennessee, with notices of the 

strata surrounding it: Am. Jour. Sci., 2d ser., v. 12, p. 852-361.
URANIUM-BEARING PHOSPHORITES IN THE UNITED STATES 31

The lower part of the Bone Valley formation is composed of quartz 

sand, clay, and phosphate nodules. The upper part of the formation 

is a clayey sand with few phosphate nodules. In some areas of the 

land-pebble district the upper part and the top of the lower part of the 

Bone Valley have been altered by acidic ground waters. The altered 

sections that reflect the original rock type are known as the leached 

zone, and are erratically distributed in the northern part of the landpebble district. The leached zone apparently does not extend into the 

southern part of the district.

The P2O5 content of the phosphate nodules in the matrix ranges 

from 30 to 36 percent, and the uranium content ranges from 0.005 to 

0.02 percent. Generally, the uranium content of the phosphorite increases as the phosphate content increases. One exception is the 

leached zone which has a higher uranium content and a lower P2O5 

content than the matrix.

The most important phosphate deposits in the western field are 

found in the phosphatic shale member of the Phosphoria formation 

of Permian age. The Phosphoria formation and its stratigraphic 

equivalents crop out in Idaho, Montana, Wyoming, and Utah, and 

have an eastern and a western f acies.

The western f acies is part of the folded Cordilleran miogeosyndine 

and is characterized by black shales, cherts, carbonaceous mudstones, 

and black phosphorites. The eastern platform f acies has a predominance of carbonate rocks, with interbedded layers of chert, sand, limestone, and low-grade phosphatic rock.

The P2O5 content of the minable beds of the Phosphoria rarely exceeds 32 percent. The uranium content of the phosphorite ranges 

from 0.01 to 0.02 percent and seems to increase in a general way with 

an increase in phosphate.

Other examples of marine phosphorites are the blue-rock phosphate 

of Tennessee which is an unaltered part of the Hardin sandstone member of the Chattanooga shale,3 phosphatic limestones of Permian age 

in central Texas, phosphate deposits in the Cason shale near Batesville, Ark.,4 and phosphatic nodules in black shales in Kansas and 

Oklahoma.

It has been suggested that the uranium in marine phosphorites 

substitutes for calcium in the phosphate mineral fluorapatite (ref. 

12, p. 28, 29); however, some uranium appears to be associated with 

the clay minerals and organic material. Most authors agree that~the 

uranium in phosphorites is of syngenetic origin and derived from sea 

water. The theory of syngenetic origin is supported by the fact that

3 Smith, R. W., and Whitlatch, G. I., 1940, The phosphate resources of Tennessee: 

Tenn. Dept. Cons., Div. Geology Bull. 48, 444 p.

* Waggaman, W. H., 1912, A report on the natural phosphates of Tennessee, Kentucky, 

and Arkansas: U. S. Bur. Soils Bull. 81, 36 p.
32 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

the uranium content of marine phosphorites is higher than that of 

continental phosphate deposits.

The marine phosphate deposits of the United States represent a 

large low-grade reserve of uranium. In 1952 the Atomic Energy 

Commission announced that the Blockson Chemical Co., near Joliet, 

111., would be the first to extract uranium from phosphate rock. Since 

then, plants in Texas City, Tex., and in Florida have started to produce uranium as a byproduct in the manufacture of wet-process 

phosphoric acid.

EXPLANATION OF THE BIBLIOGRAPHY AND INDEX MAPS

This bibliography consists primarily of annotations of published 

reports and open-file reports of the Geological Survey pertaining to 

the geology of uranium-bearing phosphorites; a few general papers 

on the geology of domestic phosphates are included. The references 

are numbered and are listed alphabetically by author.

Most of the annotations were prepared by Curtis and express the 

ideas of the authors. Where information has been added for clarification it is included in brackets. Where the author's exact words are 

used in lieu of an annotation, "Author's abstract" or a similar phrase 

appears at the end of the quotation.

The stratigraphic nomenclature as used in the bibliography is that 

of the various authors and does not necessarily correspond to the 

LT. S. Geological Survey usage.

Each locality or general area mentioned in the annotations is assigned a number for example, Locality 23, Western phosphate field. 

The localities are listed numerically on page 35 and are shown on the 

index maps, figures 2 and 3, pages 34 and 35; the locality number precedes the corresponding area in the key to localities.

ACKNOWLEDGMENTS

This compilation was done on behalf of the Division of Raw Materials of the U. S. Atomic Energy Commission.

SELECTED ANNOTATED BIBLIOGRAPHY

1 Altschuler, Z. S., 1953, Southeast phosphate minerologic and petrologic 

studies : in Search for and geology of radioactive deposits, Semiannual 

progress report, December 1,1952, to May 31,1953: U. S. Geol. Survey 

Kept. TEI-330, p. 171-176, issued by U. S. Atomic Energy Comm. Tech. 

Inf. Service, Oak Ridge, Tenn.

This is a summary of mineralogic and petrologic studies made of southeast phosphates from August 1952 to May 1953.
URANIUM-BEARING PHOSPHORITES IN THE UNITED STATES 33

A petrologic study of sections from a mine face at Homeland, Fla., where 

the aluminum phosphate zone (leached zone) transgresses the original 

stratigraphy, indicates that the mineralogy varies according to the degree 

of alteration of the rock. The minerals, listed in order from the base to 

the top of the section, are montmoilllonite and apatite in the unaltered 

area; pseudowavellite, kaolinite, apatite, and montmorillonite where alteration is first observed; psendowavellite and montmorillonite near the 

top in area«s of more intense alteration; and wavellite at the top of the 

section. Quartz, which is abundant in all samples, increases regularly 

from the base to the top.

The uranium content of the sections is increased by supergene processes 

at the base of the pseudowavellite-apatite zone.

Determination of the origin of the surface sands and of the source of 

the uranium are two major problems in regard to the leached zone of the 

land-pebble district. Field evidence indicates either a residual or depositional origin for the surface sands, and that the uranium in the 

leached zone could be a concentrated product of a once thicker section 

of slightly phosphatic, clayey, quartz sand.

Altschnler, Z. S., Clarke, R. S., Jr., and Young, E. J., 1954, Occurrence of 

uranium in phosphate deposits, petrology; in Geologic investigations 

of radioactive deposits, Semiannual progress report, June 1 to November 30, 1954: U. S. Geol. Survey Kept. TEI-490, p. 203-204, issued 

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

Samples of apatite of unusually high uranium content were studied 

by autoradiographic and nuclear emulsion methods to obtain knowledge of the distribution of uranium within them. One specimen, consisting of apatite cement in an arkose, had 0.74 percent U; another, a fossil 

bone from South Dakota, had 0.083 percent U. In both specimens the 

uranium was found to be uniformly distributed on a microscopic scale 

and not localized or concentrated in inclusions. Concentration of 

uranium occurred on a microscopic scale, peripheral areas of the bone 

being much richer than internal areas. It is interesting to note that 

uranium in these highly enriched materials occurs in the same manner 

that it does in normal sedimentary apatite of much lower grade (0.01- 

0.02 percent U), revealing that the lower grade apatites are far from saturated with uranium.

In study of well cuttings from the Clark-James tract, in the Land 

Pebble Field of Florida, it was found that the uraniferous material is 

iron stained and impregnated apatite. Although this area may have been 

secondarily altered and enriched in uranium, it is not analogous to the 

aluminum phosphate zone of the Peace River basin, as it lacks the secondary aluminum- and calcium-aluminum phosphates. In addition, an 

appreciable part of the uranium in the Clark-James tract is associated 

with goethite and limonite. This is revealed by analyses of magnetic and 

specific gravity splits in which it was found that uranium paralleled iron 

more closely than it did phosphorous or calcium. Authors' Section on 

Petrology

421223 57-
34 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

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URANIUM-BEARING PHOSPHORITES IN THE UNITED STATES 35

Locality No.

KEY TO LOCALITIES

[NOB. on figures 2 and 3] 

Locality No.

1. Land-pebble phosphate district, 

Florida.

2. Phosphate mine at Homeland, Polk 

County, Fla.

3. Anomalous radioactivity, Manatee 

County, Fla.

4. Area of phosphorite occurrences in 

the eastern Gulf of Mexico.

5. Hard-rock phosphate field, Florida.

6. Anomalous radioactivity, Marion 

County, Fla.

7. Anomalous radioactivity, Clay 

County, Fla.

8. Anomalous radioactivity, Union 

County, Fla.

9. Anomalous radioactivity, Steinhatchee area, Florida.

10. Anomalous radioactivity, Altamaha 

River drainage, Georgia.

11. Phosphate field (land rock and 

river pebble), South Carolina.

12. Titanium-apatite deposits, Amherst 

and Nelson Counties, Va.

13. Mulligan Quarry, Hunterdon 

County, N. J.

14. Canfield phosphate mine, Morris 

County, N. J.

15. Rutgers Mine, Clinton County, N. Y.

16. Mineville district, Essex County, 

N. Y.

17. White rock phosphate, Tennessee.

18. Brown rock phosphate, Tennessee.

19. Blue rock phosphate, Tennessee.

20. Phosphate field, Arkansas.

21. Area of occurrences of phosphatic 

nodules in black shale, Oklahoma 

and Kansas.

22. Phosphorite prospect, Marble Falls, 

Tex.

23. Limits of Phosphoria formation, 

western phosphate field.

24. Area of phosphorite samples taken 

off the coast of southern California.

25. Area of phosphate deposits in 

northern Alaska.

164= 156* J485 140' 132'

FIGUKE 3. Index map of nraniumrbearing phosphorites In Alaska.
36 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

3 Altschuler, Z. S., Jaffe, E. B., and Cuttitta, Frank, 1956, The aluminum 

phosphate zone of the Bone Valley formation, Florida, and its uranium 

deposits: Proc. Internat. Conf. on the Peaceful Uses of Atomic Energy, 

Geneva, 1955, v. 6, p. 507-513; U. S. Geol. Survey Prof. Paper 300, 

p. 495-504.

The Bone Valley formation of Pliocene age, which contains most of the 

land-pebble phosphates, occurs in west-central Florida, east of the Tampa 

Bay region. It unconformably overlies the Hawthorn formation of early 

and middle Miocene age and is covered by a surface mantle of quartz 

sands. It contains graded bedded pebbly and clayey phosphatic sands 

in its lower two-thirds, which are mined, and a less phosphatic massivebedded clayey sand, approximately 8-10 feet thick, in its upper third, 

which is discarded.

The upper part of the Bone Valley formation has been leached, altered 

to aluminum phosphates, and enriched in uranium in a widespread though 

discontinuous zone which averages about 6-7 feet in thickness and underlies several hundred square miles of the Peace and Alafta drainage basins. 

The areal distribution patterns with respect to the thickness, tonnage, 

and grade of the aluminum phosphate zone conform strikingly to the 

topography of the river valleys.

The Bone Valley formation was altered by weathering and ground 

water, and the vertical changes through the aluminum phosphate zone 

show a progressive change in mineralogy and texture. In typical sections carbonate-fluorapatite still prevails at the base, incipiently leached 

and altered. In the middle of the zone, the calcium aluminum phosphates 

crandallite and millisite are found, and at the top the aluminum phosphate wavellite predominates. The changes have been brought about 

by phosphatization of clay and by alumina alteration of apatite.

Much apatite and clay have been leached and replaced in the aluminum 

phosphate zone, and its rock is generally white, friable, and highly 

porous; however, its character has been greatly influenced by the primary Bone Valley petrography. Thus, where graded bedded pebbly rock 

is altered, coarse, frequently graded, vesicularity results; where massive 

clayey sand is altered, fine porosity prevails, and aluminum phosphates 

are more common.

The uranium content of unaltered rock of the lower part of the Bone 

Valley is approximately 0.008 percent; its P2O6 content is about 15 percent. 

Unaltered rock of the upper part of the Bone Valley contains much less 

uranium and P2O5 . By contrast, a well-developed section of aluminum 

phosphate zone typically has 0.012 percent uranium and approximately 

8-10 percent P2OS . Within the aluminum phosphate zone, uranium increases as calcium does, and the more calcic phosphates are more uraniferous. In addition, supergene processes have caused a subzone of basal 

enrichment in the aluminum phosphate zone in which individual apatite 

specimens contain as much as O.X percent uranium. Except for a single 

trace occurrence of autunite, no uranium minerals have been found in 

the Bone Valley formation.

The aluminum phosphate zone is a potentially valuable resource of 

uranium, phosphate, and alumina, particularly as it must be stripped 

anyway to mine the underlying apatite deposits, and its rock can be 

readily beneficiated by removal of quartz, the major diluent. Authors' 

abstract
URANIUM-BEARING PHOSPHORITES IN THE UNITED STATES 37

Barnes, V. E., 1954, Phosphorite in eastern Llano Uplift of central Texas: 

Texas University Bur. Econ. Geology, Kept. Inv. no. 23, 9 p.

A radioactive deposit of phosphorite, estimated to be 11 feet thick, is 

exposed about l1/^ miles south of Marble Falls, Burnet County, Tex., in 

a road-material pit on the eastern side of an outlier of Carboniferous age. 

The deposit consists of interbedded phosphate rock and limestone with 

phosphatic nodules. Stratigraphically the deposit lies above shale typical 

of that in the Barnett formation of Mississippian age, and beneath spiculitic limestone at the base of the Pennsylvania Marble Falls formation. 

Other thin phosphate zones are known in the Llano uplift, all of which 

are abnormally radioactive.

The phosphorite is composed mostly of well-rounded grains between 

0.1 and 0.6 mm in diameter. Most of the grains are oolitic, a few appear 

to be structureless pellets, and others are parts 6f organisms.

Phosphatic nodules are found in limestone beds, the lower of which is 

highly fossiliferous in places. Brachiopods are most abundant, and gastropods, cephalopods, and corals are common. The upper limestone beds 

are less fossiliferous and contain fewer phosphate nodules. The phosphatic 

nodules in the limestone are pale to dark yellowish-brown on the fresher 

surfaces, and a dark yellowish-orange where weathered.

Chemical analysis of a sample of the bed from 3 inches to 5 feet above 

the base of the deposit showed a PsO5 content of 13.92 percent, and a 

chemical analysis of the bed from 5 to 8^ feet above the base showed a 

P2Os content of 15.18 percent. The phosphorite is estimated to contain 

about 0.017 percent U3O8 (by comparison, using a Geiger counter and an 

analyzed sample of phosphate rock known to contain 0.029 percent U3OS ). 

[Analysis of a sample of phosphorite from the same area by the U. S. 

Geological Survey shows 0.006 percent equivalent uranium.]

The deposit is estimated to contain 5,000 tons of phosphorite. An additional 35,000 tons of phosphorite may be present in an outlier to the 

northeast, although no abnormal radioactivity was noted there. These 

deposits are of low grade, small tonnage, and have a questionable commercial value.

Bergendahl, M. H., 1955, Wavellite spherulites in the Bone Valley formation of central Florida: Am. Mineralogist, v. 40, nos. 5 and 6, p. 

497-504.

Megascopic spherulitic aggregates of wavellite have been recently found 

in the Florida land-pebble phosphate field. Petrographic studies were 

made to establish the identity of the mineral. Chemical and spectrographic data revealed the spherulites to be practically pure wavellite; the 

remainder is composed of phosphatic cement partly altered to wavellite. 

The origin of wavellite is considered to be secondary, a replacement of 

apatite that has undergone ground-water leaching. Author's abstract

Carswell, L. D., and McKelvey, V. E., 1954, Effects of weathering on 

phosphate rocks; in Geologic investigations of radioactive deposits, 

Semiannual progress report, June 1 to November 30, 1954: U. S. Geol. 

Survey Kept. TEI-490, p. 193-194, issued by U. S. Atomic Energy 

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

The investigation of the effects of weathering on the composition of 

phosphate rock continued, with the collection of a suite "of about 80 samples 

from various levels of the Anaconda Copper Mining Company's mine at
38 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

Conda, Idaho, and the transmittal for analysis of several hundred samples 

cut by the San Francisco Chemical Company from exploratory workings 

in the Crawford Mountains. Analyses furnished by both the Anaconda 

Company and the San Francisco Chemical Company on samples collected 

from their mines show a steady decrease in phosphate content in highgrade rocks of the lower bed from about 33 percent P2O3 near the surface 

to 30 percent or less a few scores or hundreds of feet below the surface. 

Results of a few analyses made by the U. S. Geological Survey on the 

San Francisco Chemical Company's samples from the Crawford Mountains 

show that, as the phosphate content decreases, the percent loss on ignition 

increases in [an] amount that nearly compensates for the decrease in phosphate, This suggests that the chief effect of weathering is leaching of 

carbonaceous matter and carbonates.

Coatings of a secondary uranium mineral, probably tyuyamunite, were 

found by the San Francisco Company in its Crawford Mountain workings, 

showing that some uranium is leached during weathering and redeposited 

at depth. Uranium analyses on the samples show no indication, however, 

of any notable enrichment nor of any persistent trend in variations in the 

uranium content with depth. Authors' complete text

1 Cathcart, J. B., 1950, Notes on the land-pebble phosphate deposits of 

Florida; in Snyder, F. G., (ed.), Symposium on mineral resources of 

the southeastern United States, 1949 proceedings: p. 132-151, The 

Univ. of Term. Press, Knoxville, Tenn.

The phosphate deposits in Florida are the land-pebble deposits of 

marine origin and of Pliocene age such as those in the Bone Valley formation, the hardrock deposits of continental origin, formed as replacement bodies in earlier limestone and as fluvial concentrations in Pliocene 

stream channels, and the river-pebble phosphate of continental origin 

which is found as bars and on flood plains along modern streams.

The phosphorites contain small quantities of uranium, which probably 

is in the phosphate mineral (a fluorapatite). The supposition that the 

source of the uranium was sea water is supported by the fact that the 

marine Bone Valley formation has a higher uranium content than the 

continental hardrock. The Bone Valley formation has a higher uranium 

content, and possibly accumulated more slowly than the underlying marine 

Hawthorn formation. This fact suggests that the longer the time of exposure of the phosphate nodules to the sea water, the greater their uranium 

content.

8 Cathcart, J. B., 1953, Economic geology, land-pebble phosphate district 

(Florida) ; in Geologic investigations of radioactive deposits, Semiannual progress report, June 1 to November 30,1953: U. S. Geol. Survey Kept. TEI-390, p. 175, issued by U. S. Atomic Energy Comm., Tech. 

Inf. Service, Oak Ridge, Tenn.

The Peace River area, Florida, may be divided into three physiographic 

units: the ridge, the flatwoods, and the valley and flood plain of the river. 

The aluminum phosphate zone is thickest, most continuous, and highest in 

Pa Oe and U in the flatwoods region, is thin and discontinuous, or absent in 

the ridge area, and is absent in the flood plain and valley of the Peace 

River. Analytical data indicate that areas of high P2OC and high U are 

generally the same, and in general these high areas are also the thicker 

sections. However, detailed drilling has shown the extreme lateral vari-
URANIUM-BEARING PHOSPHORITES IN THE UNITED STATES 39

ations in both thickness and analyses, from possibly minable to unminable areas in as little as 200 feet. It seems likely that very detailed drilling 

will be necessary before mining in order to predict feeds for a plant, and 

that some surge capacity and mixing facilities will be necessary to maintain a uniform feed.

9 Cathcart, J. B., 1954, Drilling of airborne radioactivity anomalies in 

Florida, Georgia, and South Carolina: U. S. GeoL Survey Open-file 

Kept., 11 p.

Areas of abnormal radioactivity, as recorded by airborne surveys in 

Florida, in general were proved by drilling to be underlain, at shallow 

depths, by uranium-bearing phosphatic rocks. In Marion County, Fla., 

drilling within the area of anomalous radioactivity showed aluminum 

phosphate material very close to the surface; check holes drilled outside 

the areas of anomalous radioactivity showed thick, barren quartz sand at 

the surface. However, several areas of anomalous radioactivity were 

drilled and checked with a scintillation counter without finding any 

anomalous radioactivity. In the area near Olustee Creek, in Union 

County, Fla., and in the Steinhatchee area, the reason anomalous radioactivity was not found may be that the anomalous areas, as shown on 

county road maps, are misplotted. County roads in both cases are shown 

cutting across the edges of the anomalous areas, and if the line enclosing 

the area of anomalous radioactivity \\ere moved only a short distance, the 

roads would be out of the areas and would be blank as the drilling 

indicated.

In Clay and Manatee Counties, Fla., and in the Altamaha River drainage in Georgia, the anomalies were very slight, only about twice background, and reasons for finding no anomalous radioactivity on the ground 

are not known.

In general, therefore, it would seem that anomalies which are greater 

than about twice background indicate the presence of uranium-bearing 

phosphatic rocks at or near the surface, while those anomalies which are 

only about twice background may or may not indicate the presence of 

phosphate rock. Author's abstract

10 Cathcart, J. B., 1956, Distribution and occurrence of uranium in the calcium phosphate zone of the land-pebble phosphate district of Florida: 

Proc. Internat. Conf. on the Peaceful Uses of Atomic Energy, Geneva, 

1955, v. 6, p. 514-519; U. S. Geol. Survey Prof. Paper 300, p. 489-494. 

The land-pebble phosphate district, in west-central peninsula Florida, 

comprises more than 1,000 square miles, mostly in Polk and Hillsborough 

Counties. Lower grade phosphate deposits also occur in the south.

The Tampa limestone of early Miocene age is exposed only in the northernmost part of the area, where the Hawthorn formation of early and 

middle Miocene age thins to a feather edge. The Hawthorn formation 

contains minor to trace amounts of phosphate particles; and where the 

carbonate has been removed by weathering, the residual concentration of 

phosphate particles and quartz sand is called "bedclay," and may form a 

part of the matrix.

The Bone Valley formation of Pliocene age has been leached by acid 

ground waters, forming a zone characterized by aluminum phosphate 

minerals. This zone, locally called the "leached zone," commonly contains between 0.010 and 0.015 percent uranium.
40 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

The matrix, or calcium phosphate zone, constituting the lower phosphorite part of the Bone Valley formation, and the upper residual part of 

the Hawthorn formation, consists essentially of equal parts of quartz sand, 

phosphate particles (+150 mesh), and slime ( 150 mesh). The central 

area of the Bone valley formation contains predominantly coarse (4-14 

mesh) phosphate, and the surrounding areas contain predominantly fine 

( 14-f 150 mesh) phosphate. The analysis of many thousands of samples 

has shown that the coarser phosphate particles are higher in uranium 

and lower in P2O3 content than the finer material. Uranium content of 

the coarser material (pebble) averages between 0.010 and 0.020 percent, 

and the P2O3 content averages about 31.5 percent. The uranium content 

of the finer materials (concentrates) is commonly between 0.005 and 0.015 

percent, and the P205 content averages about 34 percent. A direct relation 

between PoQs content and U content is present, however, within a size 

fraction: in pebble samples of the same size, the U content tends to 

increase as the P2O5 increases.

The uranium content of the quartz sand fraction of the matrix Is 

less than 0.001 percent, and the slime fraction of the matrix usually contains small amounts of uranium, averaging less than 0.005 percent, although some samples very high in P^O.-, content have a higher uranium 

content.

It is believed that the uranium is syngenetic, and was absorbed by the 

phosphate particles as they formed on the sea floor. This might account 

for the observed higher uranium content of the coarser materials, because 

they were probably exposed for longer periods of time to the action of 

sea water than were the smaller particles. Author's abstract

11 Cathcart, J. B., Blade, L. V., Davidson, D. F., and Ketner, K. B., 1953, The 

geology of the Florida land-pebble phosphate deposits; in Origine des 

gisements de phosphates de chaux: Gong. Geol. Internal., I9e , Alger, 

Comptes rendus 1952, Sec. 11, Fas. 11, p. 77-91 (see p. 77). 

The land-pebble phosphate district is on the Gulf Coastal Plain of Florida. 

The phosphate deposits are in the Bone Valley formation, dated Pliocene 

by most writers. These strata overlie the Miocene Hawthorn formation, 

and are overlain by unconsolidated sands 3 to 20 feet thick.

The mineable phasphate deposits, called "matrix" in the district, range 

from a featheredge to about 50 feet in thickness and consist of phosphatic 

pellets and nodules, quartz sand, and inontmorillonitie clay in about equal 

proportions. Locally the matrix displays cross-bedding and horizontal 

laminations, but elsewhere it is structureless. The phosphorite particles, composed largely of carbonate-fluorapatite, range in diameter from 

less than 0.1 mm to about 60 cm, and in P3O5 content from 30 to 60 percent. Coarse-pebble deposits, containing 30 to 34 percent P2O5 , are found 

mainly on basement highs; and fine-pebble deposits, containing 32 to 36 

percent P2O5 are found in basement lows. Deposits in the northern part 

of the field contain more phosphate particles and their P3O5 content is 

higher than those in the southern part.

The upper part of the phosphatic strata is leached to ai- advanced degree 

and consists of quartz sand and clay-sized particles of pseudowavellite 

and wavellite. The leached zone ranges in thickness from a featheredge 

to 60 feet.
URANIUM-BEARING PHOSPHORITES IN THE UNITED STATES 41

The origin of the land-pebble deposits is incompletely known. Possible 

modes of origin are a residuum of Miocene age, or a reworked residuum of 

Pliocene or Quarternary age. Authors' abstract

12 Davidson, C. F., and Atkin, D., 1953, On the occurrence of uranium in phosphate rock; in Origine des gisements de phosphates de chaux: Gong. 

Geol. Internat, 19e, Alger, Comptes rendus 1952, Sec. 11, Fas. 11, 

p. 13-31 (seep. 29).

It has been known since the investigations of Strutt over forty years ago 

that phosphorites, apatite crystals, and fossil bones are richer in uranium 

than the average rocks of the earth's crust. In the present study a 

quantitative examination has been made of the uranium content in commercial phosphate rocks from North Africa, America [Florida, South 

Carolina], various localities in Europe, and the Oceanic Islands. A considerable range of values has been found, the Ocean Island phosphorites 

possessing a low radioactivity and the phosphate rocks of marine deposition showing high uranium, especially where the carbonate content is 

low. Fossil bones and apatite crystals also contain a little uranium, the 

highest value found being 0.55 percent eU8O8 in a Middle Old Red Sandstone fossil fish from Sutherland [Great Britain]. Aluminum phosphates, 

such as variscite and turquoise, may display a significant radioactivity. 

It is concluded that, at least in most instances, the uranium is present in 

the apatite of the phosphorite of bone as a proxy for calcium, and that it is 

derived principally from percolating waters. Where the apatite or phosphorite is of a porous nature the substitution has usually proceeded uniformly throughout the mass; where it is compact or impervious replacement is concentrated towards the edges. Authors' summary

13 Dietz, R. S., Emery, K. O., and Shepard, F. P., 1942, Phosphorite deposits 

on the sea floor off southern California: Geol. Soc. America Bull., 

v. 53, no. 6, p. 815-848.

Submarine phosphorite deposits are found off the coast of Southern 

California from Monterey Bay south to the Gulf of California. Samples 

of phosphorite were collected from the sea bottom, as well as from the 

tops and sides of offshore banks. The deposits are found in Miocene to 

Recent sediments, but no positive identification of the age of the strata 

could be made.

The mode of occurrence of the phosphorite ranges from thin flat slabs 

to nodular masses. Phosphorite also is found as coatings on hard compact 

rock, as fillings in porous rock, and as a cement of fragments of darker 

phosphorite and other rocks.

The nodules are generally hard and dense, and have smooth glazed 

surfaces and a fresh appearance. Their surface consists of a thin discolored layer of phosphorite or of manganese oxide. Freshly broken 

surfaces are usually light to dark brown. Cellophane is the principal 

mineral form of the phosphate. Francolite(?) is sometimes associated 

with the cellophane. The majority of the nodules are irregularly layered, 

many are conglomeratic, and nearly all the phosphorite is somewhat 

oolitic. Many nodules enclose foreign material such as foraminiferal 

tests, grains of clastic minerals, and glauconite.

Six samples that were analyzed chemically have an average of 28.15 

percent P2O5 , 44.91 percent CaO, and 3.11 percent F. Insoluble residues

421228 57 3
42 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

comprised from 6 to 30 percent of the samples; the fine fraction consisted 

dominantly of amorphous silica and carbonaceous material; the coarse 

fraction consisted of glauconite, mineral grains, carbonaceous particles, 

and siliceous animal remains.

That the phosphorite was deposited essentially in place is suggested 

by the following facts: the one-sided marnmillary surfaces formed by 

growth layers on many nodules; the large size of many of the nodules, 

and their lack of abrasion; the close resemblance of the sediment enclosed 

in the nodules with the surrounding sediment; and the nondepositional 

environment [probably meaning the paucity of clastic sediments being 

deposited at present] which prevails on the sea floor off southern California.

The authors conclude that the nodules were deposited on the present 

banks, shelves and canyon walls during the Quaternary, and that previously an abundance of Miocene foraminif era had been eroded or weathered 

out of Miocene formations and concentrated on surfaces upon which the 

phosphorite deposition gradually took place.

14 Emery, K. O., and Dietz, R. S., 1950, Submarine phosphorite deposits off 

California and Mexico: Calif. Jour. Mines and Geology, v. 46, no. 1, 

p. 7-17.

This paper is mostly a resurnS of the paper by Dietz, Emery, and Shepard 

(ref. 13) with the addition of data on the radioactivity of some of the 

nodules. Samples of phosphorite were taken from submarine areas off 

the coast of southern California. The sea sediments are Miocene to 

Recent in age. The beta-radioactivity of 10 nodules from areas off the 

coast of California ranged from 41 to 65 counts per minute per gram. 

The background was 22 counts per minute.

15 Gould, H. R., 1953, Phosphate studies in the eastern Gulf of Mexico; in 

Search for and geology of radioactive deposits, Semiannual progress 

report, December 1, 1952, to May 31, 1953, p. 176-180: U. S. Geol. 

Survey Rept. TEI-330, issued by U. S. Atomic Energy Ctomm., Tech. 

Inf. Service, Oak Ridge, Tenn.

The purpose of the investigations of the phosphorite deposits in the 

eastern Gulf of Mexico was to determine the areal distribution, quality, 

source and mode of formation of the phosphatic sediments.

Preliminary results show that the continental shelf between Tarpon 

Springs and Fort Meyers, Fla., consists of an inshore zone 20 miles wide 

and an outer zone 100 miles wide. The inshore zone is characterized by 

detrital sands composed chiefly of quartz. Generally, only traces of 

phosphorite were found in this zone. Visual comparison with chemically 

analyzed samples indicate that samples from this zone have a P2O5 content 

of less than 0.50 percent and a uranium content of less than 0.0001 percent. 

However, a few of the samples analyzed chemically have maximum contents of 13.4 percent P2O5 and 0.004 percent uranium.

Almost no phosphorite was detected in the offshore zone, which is characterized by calcareous sands of organic origin. These sediments have a 

P2O5 content of less than 0.15 percent and a uranium content of less than 

0.0001 percent.

The characteristics of the phosphorite in the two zones suggest that it is 

detrital material transported by streams from peninsular phosphate deposits and from adjacent phosphatic beaches.
URANIUM-BEARING PHOSPHORITES IN THE UNITED STATES 43

16 Harris, R. A., Davidson, D. F., and Arnold, B. P., 1954, Bibliography of the 

geology of the western phosphate field: U. S. Geol. Survey Bull. 1018, 

89 p.

Nearly all papers published before September 1952 on the geology of 

phosphate deposits in Alberta and British Columbia, Colorado, Idaho, 

Montana, Utah, and Wyoming have been included in this bibliography. 

There is also a section on the mineralogy and chemical composition of 

phosphorites in other regions. The section on areal geology includes only 

the publications that describe the geology of areas in which the Phosphoria 

formation or its partial stratigraphic equivalents, the Park City and Embar 

formations, are found. The other sections include papers on the stratigraphy, regional structure, fuels, and mineral deposits other than phosphate. Entries are liberally cross indexed.

17 Jacob, K. D., Hill, W. L., Marshall, H. L., and Reynolds, D. S., 1933, The 

composition and distribution of phosphate rock with special reference 

to the United States: U. S. Dept. of Agriculture Tech. Bull. 364, 90 p.

A brief review of the phosphate deposits and the production and reserves of phosphate rock in the United States is given. The flotation 

process of concentrating low-grade phosphate ores is discussed with reference to its value in the conservation of the phosphate deposits in the 

southeastern part of the United States.

The results of an analytical study of 46 samples of mineral calcium 

phosphates representing nearly all of the more important domestic types 

and sources of this material are presented. Data are also given on the 

composition of 11 samples of bone ash, apatites, and foreign phosphate 

rocks, and on the percentages of fluorine and phosphoric acid in a large 

number of additional samples from deposits throughout the world.

Phosphoric acid, lime, alumina, iron, silica, carbon dioxide, fluorine, and, 

in most samples, sulphate are the predominating constituents of domestic 

phosphate rock. Magnesium, titanium, sodium, potassium, manganese, 

chromium, copper, zinc, arsenic, chlorine, and iodine are present in nearly 

all samples, but only in comparatively small quantities. Small percentages of vanadium are also present in many samples.

Phosphate rock from continental deposits usually contains 3 to 4 

percent of fluorine, whereas that from insular deposits contains smaller 

quantities. As a general rule, the fluorine-phosphoric acid ratios in a 

particular type of rock are approximately constant. Although fresh 

bones are very low in fluorine, fossil bones frequently contain high percentages of this element. Evidence is presented to show that the fluorine 

in phosphate rock and fossil bones originates principally from contact of 

the phosphates with fluorine-bearing waters, and that, to a certain extent, 

there is a rough correlation between the fluorine content and the geological 

age of these materials.

The commercial types and grades of domestic phosphate rocks contain 

approximately the following percentages of minor constituents MgO, 0.0 

to 0.5; Ti62, 0.02 to 0.15; Na2O, 0.1 to 0.8; K2O, 0.05 to 0.65; MnO, traces 

to 0.3; Cr2O8, 0.00 to 0.15; V2OS, 0.00 to 0.40; CuO, <0.0005 to 0.01; ZnO, 

<0.0005 to 0.025; AsaOa, 0.001 to 0.015; and Cl, 0.00 to 0.10. The iodine 

content ranges from approximately 1 to 130 parts per million.

Pyrite is a common constituent of Tennessee blue rock and phosphatic 

limestone, South Carolina land rock, and rock from Cokeville, Wyo.
4/4 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

The organic matter isolated from phosphate rock carries high percentages of nitrogen and sulphur, and the ash of this material is rich 

in iron.

In comparison with the other types of domestic phosphate rock, Tennesee brown-rock phosphate is characterized by the presence of high 

percentages of aluminum, iron, and manganese, and by the absence of 

vanadium. It usually contains more potassium than sodium, whereas 

the reverse is the rule with the other types.

Tennessee blue-rock phosphate is similar to Tennessee brown rock in 

that it is comparatively high in iron. It is also high in acid-soluble sulphate, but its outstanding characteristic is its high content of acidinsoluble sulphide, principally pyrite.

Florida land-pebble phosphate has no outstanding chemical characteristic. The percentages of fluorine in the different commercial grades of 

this material are, however, approximately constant, whereas in the 

other types of phosphate rock the fluorine content varies, as a general 

rule, directly with the phosphoric acid.

Florida hard-rock phosphate is characterized by its comparatively high 

content of iodine, and low content of sulphate and chlorine.

In general, the phosphates from deposits in the Rocky Mountain States 

are comparatively high in chromium and vanadium, and low in iodine. 

Certain samples, notably those from deposits at Conda, Idaho, and 

Cokeville, Wyo., are exceptionally high in organic carbon and organic 

sulphur, whereas rock from the Garrison, Mont, deposit is low in organic 

carbon and in total sulphur.

In comparison with phosphate rock, Florida waste-pond phosphate is 

low in phosphoric acid and exceptionally high in silica and alumina. 

The composition of Florida soft phosphate varies considerably with 

different samples.

Nearly all of the elements present in phosphate rock occur also in 

bone ash.

Analyses of the mechanical fractions separated from samples of ground 

phosphate rock and from Florida soft and waste-pond phosphates showed 

that, as a general rule, the phosphoric acid, calcium, and fluorine concentrate somewhat in the "sand" and "silt" fractions, whereas the alumina 

and silica concentrate to a marked extent in the "clay" and colloid fractions, particularly the latter.

Phosphate rock does not contain significant quantities of phosphoric acid 

soluble in neutral ammonium citrate solution, and less than 30 percent 

of the total phosphoric acid is soluble in 2 percent citric acid solution. 

The percentages of phosphoric acid dissolved by these reagents from a 

particular sample of phosphate increase with increase in the fineness of the 

particles.

The principal phosphatic component of phosphate rock from continental 

deposits is fluorapatite, which is present almost entirely in the submicrocrystalline condition. Hydroxyfluorapatite is an important con- 

^ ; stituent of rock from insular deposits. The available data indicate that 

domestic phosphate rock may contain small quantities of carbonate apatite 

and hydroxyapatite. Author's abstract
URANIUM-BEARING PHOSPHORITES IN THE UNITED STATES 45

18 Ketner, K. B., 1955, A bibliography of phosphate deposits in southeastern

United States: U. S. Geol. Survey Open-file Kept., 18 p. 

The bibliography includes references published before 1954 on the 

geology of phosphate deposits in South Carolina, Georgia, Alabama, and 

Florida.

10 McKelvey, V. E., 1955, Search for uranium in the United States: U. S.

Geol. Survey Bull. 103G-A, p. 1-69. (See p. 16, 17, 37.) 

Uranium is concentrated in phosphorites by chemical adsorption processes, either at the time of deposition of the phosphorite, or before the 

phosphatic material was buried. Generally, appreciable amounts of 

uranium are found only in noncalcareous marine phosphorites with a 

P2O5 content of more than 25 percent. Residual deposits derived from 

the weathering of phosphatic limestones usually have a low uranium content unless they have been exposed to sea water or other uranium-bearing 

solutions.

20 McKelvey, V. E., 1956, Uranium in phosphate rock; Proc. Internat. Conf. 

on the Peaceful Uses of Atomic Energy, Geneva, 1955, v. 6, p. 499-502: 

U. S. Geol. Survey Prof. Paper 300, p. 477-481.

Marine phosphorites commonly contain 0.005 to 0.03 percent uranium. 

The uranium content increases roughly with increasing phosphate content 

but is generally low in rocks that contain more than a few percent CO2 . 

Aluminum phosphate deposits that have been derived from the weathering of marine phosphorites and phosphatic nodules in some marine black 

shale formations contain similar amounts of uranium. Most of the 

uranium in these materials does not occur as a separate mineral phase 

but substitutes for calcium in carbonate fluorapatite or crandallite. A 

few occurrences of tyuyamunite and torbernite have been reported from 

highly weathered marine phosphorites, however, and these and other 

secondary uranium minerals, such as carnotite and autunite, are not uncommon in fossil bones and teeth that have been exposed to uraniumbearing solutions after burial. Because the marine phosphorites are of 

wide extent they contain large tonnages of uranium, some of which can 

be recovered, under favorable conditions, as a byproduct of the manufacture of triple super phosphate. Author's abstract

21 McKelvey, V. E., and Carswell, L. D., 1956, Uranium in the Phosphoria 

formation: Proc. Internat. Conf. on the Peaceful Uses of Atomic Energy, Geneva, 1955, v. 6, p. 503-506; U. S. Geol. Survey Prof. Paper 300, 

p. 483-487.

The PhospLoria formation of Permian age and its close stratigraphic 

correlatives consist of two overlapping couplets, each composed of a lower 

carbonaceous, phosphatic unit, overlain by a cherty or carbonatic unit. 

Phosphate deposits are found in the Phosphoria formation over an area of 

about 135,000 square miles in Montana, Idaho, Utah, and Nevada, but the 

richest deposits are confined to a central area in eastern Idaho and adjacent parts of Montana, Wyoming, and Utah. Nearly all the phosphatic 

beds are uraniferous but their uranium content ranges from about 0.001 to 

0.065 percent Although some highly phosphatic beds are only weakly 

uraniferous, the phosphate beds that are more than 3 feet in thickness and
46 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

that contain more than 31 percent PSO5 generally contain 0.01 to 0.02 percent uraninm. Most of the differences in uranium content of the phosphate rocks cannot be correlated with other observable differences in their 

physical or chemical properties. As a rule, however, beds composed of 

pellets and oolites are more uraniferous than those composed of fish scales, 

brachiopod shells, and other organic remains; and highly weathered phosphate beds contain less uranium than their unweathered equivalents.

Most of the uranium seems to occur in carbonate-fluorapatite, where it 

probably substitutes for calcium; but tyuyamunite has been discovered in 

one area where the rocks are highly weathered. Author's abstract

22 McKelvey, V. E., Cathcart, J. B., Altschuler, Z. S., and others, 1953, Domestic phosphate deposits, in Pierre, W. H., and Norman, A. G., ed., Soil 

and fertilizer phosphorus in crop nutrition, v. 4, p. 347-376, of Agronomy, a series of monographs, prepared under auspices Am. Soc. Agronomy : New York, Academic Press, Inc.

There are six important geologic types of phosphate deposits in the 

United States. They are apatite deposits of igneous origin, residual phosphorites, marine phosphorites, river-pebble deposits, phosphatized rock, 

and quano. The characteristics of each type are discussed and representative chemical analyses are given.

Concentrations of one type or another are found in 30 of the states, although only some of the states Pensylvania, Virginia, North Carolina, 

South Carolina, Georgia, Alabama, Florida, Tennessee, Kentucky, Arkansas, Idaho, Wyoming, Utah, and Montana have produced phosphate rock. 

At present, the only production is from the landrpebble district and the 

hard-rock field of Florida, the brown-rock field of Tennessee, and from the 

Permian phosphorite deposits in Idaho, Montana, Wyoming, and Utah. 

Future production is likely to be limited to these fields.

The authors discuss the types of phophate deposits found throughout the 

United States, and estimate the total reserves of minable phosphate to be 

5 billion tons of rock containing 1.5 billion tons of PaQs. In addition, the 

reserves of lower grade material total nearly 50 billion tons of rock that 

contains 12 billion tons of P2O5.

23 McKelvey, V. E., and Nelson, J. M., 1950, Characteristics of marine uranium-bearing sedimentary rocks: Econ. Geology, v. 45, no. 1, p. 35-53.

All marine phosphorites tested before 1949 contain from less than 0.01 

to 0.02 percent uranium. The Permian Phosphoria formation in the west 

and the Pliocene Bone Valley formation in Florida represent the largest 

deposits of this type in the United States.

Uranium is also found as a constitutent of phosphatic nodules from 

shales; the uranium content of the nodules is higher, generally, than that 

of the surrounding shale. Such uraniferous phosphatic nodules are found 

in the shale at the top of the Checkerboard limestone member of the 

Coffeyville formation and in the Fort Scott limestone of Oklahoma; and 

in the Hushpuckney and Stark shales of Kansas.

In general, the uranium content of the phosphorite increases as the 

phosphate content increases, although there are many exceptions in this 

country. The uranium is believed to be in the phosphate mineral which 

is a fiuorapatite.

Local factors may influence the amount of uranium deposited. In 

the Bone Valley formation in Florida, for example, analyses of samples
URANIUM-BEARING PHOSPHORITES IN THE UNITED STATES 47

suggest that there is a higher uranium concentration in the phosphorites 

with a clay-size matrix than in those with a sandy matrix. The uranium 

content of phosphorite beds may also vary with the thickness of a given 

formation, depending on whether or not the uranium-bearing materials 

cause the increase in thickness or are diluted by the increased amounts of 

non-uraniferous materials.

Phosphorite formations are characteristically thin, but probably represent the entire depositional products of long periods of time.

The uranium hi phosphorite is of syngenetic origin; it is probably derived 

from sea water either by direct precipitation as an inorganic uranium 

salt, or by the selectivity of organisms or substances for which it has 

an affinity.

If it is assumed that the uranium is precipitated and fixed in the sediments in these ways, its later concentration may result from conditions 

that lead to the concentration of the phosphate, organic matter, or other 

substances with which the uranium is associated. An environment that 

does not favor the influx of large amounts of clastic material or the precipitation of large amounts of carbonate is a basic necessity for the 

deposition of uranium in a marine basin. The height of the adjacent 

land masses, the dimensions and configuration of the basin of deposition, 

and the climate control the development of such an environment.

The authors believe that relatively thin beds of phosphorite such as 

those described should be investigated further because they are likely 

to contain significant amounts of uranium.

24 McKelvey, V. E., Swanson, R. W., and Sheldon, R. P., 1953, The Permian 

phosphorite deposits of western United States; in Origine des gisements de phosphates de chaux; Gong. Geol. Internat., 196 , Alger, Cornptes rendus, 1952, sec. 11, fasc. 11, p. 46-64.

The Permian Phosphoria formation and its stratigraphic equivalents 

comprise about 135,000 square miles of marine sediments in Idaho, Montana, Wyoming, and Utah. There are two facies of the formation; the 

western one is of the folded Cordilleran miogeosyncline, and the eastern 

one is a platform facies. The western facies is characterized by black 

shales, cherts, carbonaceous mudstones, and rich black phosphorites. The 

eastern facies has a predominance of carbonate rocks, with interbedded 

layers of chert, sand, limestone, and weakly phosphatic rock.

The phosphorites of the Phosphoria formation are a colloform carbonate-fluorapatite mixed with detrital silicates and other material. 

Minor amounts of more than 35 metals, including uranium, are found in 

the Phosphoria formation. Uranium and the rare earths are more abundant in the phosphorites than in other rocks of the Phosphoria formation. 

The uranium probably occurs in the carbonate-fluorapatite mineral. Most 

of the metals are not abundant in calcareous phosphorites; in fact, uranium appears to decrease in the phosphorites as the CO2 content rises to as 

much as 4 percent.

The grade of minable phosphate beds is usually not more than 32 percent PaOs. The PaOs content seems to increase westward to about the center 

of the geosynclinal facies, as does the amount of carbonaceous matter and 

the quality of the phosphate rock. However, the carbonate content, the 

size of the phosphorite particles, and the grain size of the clastic material 

decrease to the west. Some of the minor metals, such as uranium and
48 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

vanadium, are more abundant in the geosynclinal facies in the west, than 

in the eastern platform facies.

The composition and facies changes of the phosphorite are indicative of 

marine deposition controlled mainly by pH, CO2 content, temperature, and 

depth. The presence of phytoplankton is also a contributing factor in the 

deposition of the phosphorite. The authors present an excellent discussion of the theory of the origin of the deposits which is similar to, but 

modified from, that proposed by Kazakov.

25 McKeown, F. A., and Klemic, Harry, 1953, Reconnaissance for radioactive 

materials in northeastern United States during 1952: U. S. Geol. 

Survey Kept. TEI-317 A., 68 p., issued by U. S. Atomic Energy Comm., 

Tech. Inf. Service, Oak Ridge, Tenn.

The geology and radioactivity of magnetite-apatite mines and prospects, 

which are not significant as possible sources of radioactive elements, are 

presented in table form. A few deposits that have a possible potential 

as sources of radioactive elements are described in detail; some of these are 

described briefly below.

The Mineville group of magnetite mines is in the Mineville district, near 

Mineville, Essex County, N. Y. The Miller, Old Bed, and "21" BonanzaJoker, are three faulted parts of one complexly folded ore bed in the 

Mineville group. The ore is massive and granular; apatite is a constituent 

of the gangue in rich as well as lean ore. The Old Bed is the richest ore 

body and contains the highest percentage of phosphorous (1 to 1.25 percent). Granular high-grade ore generally contains the least amount of 

apatite and other gangue minerals. Medium- to fine-grained ore (magnetite grains less than about 2 mm across) contains radioactive fluorapatite-rich layers and stringers, as well as disseminated fluorapatite.

Chemical analysis of a sample of hand-picked apatite grains shows a 

uranium content of 0.018 percent and a thorium content of 0.04 percent. 

The amount of radioactivity of various samples seems to be a function of 

the amount of red or flesh-colored apatite present in the sample.

The Canfleld phosphate mine is about 2 miles west of Dover, Morris 

County, N. J. The ore is a granular aggregate of magnetite and greenishgray apatite, with quartz, feldspar, and biotite as minor constituents. 

The mine was originally explored for magnetite, but the high apatite content made the material worthless as an ore of iron, and the mine was 

abandoned. Among the rocks on the dump, those with the highest apatite 

content are also the most radioactive. Radioactive monazite is also present in small amounts.

The rocks of the Rutgers mine, Clinton County, N. Y., and the Mulligan quarry, Hunterdon County, N. J., also have some apatite, but the 

geology is described only briefly in this report.

26 Mansfield, G. R., 1927, Geography, geology, and mineral resources of part

of southeastern Idaho: U. S. Geol. Survey Prof. Paper 152, 207 p.

The principal mineral resource of southeastern Idaho is phosphate

rock, which occurs at two horizons, upper Mississippian and Permian,

but only the Permian rock has much commercial value. This rock is

characterized chiefly by its oolitic texture and generally dark color and

by its odor when freshly broken, which resembles that of crude petroleum.

It is a bedded deposit of marine origin and will have to be mined in the

same manner as coal.
URANIUM-BEARING PHOSPHORITES IN THE UNITED STATES 49

The phosphate rock is really a mixture or "solid solution" of several 

phosphatic minerals, but the chemical composition is approximately that 

of tricalcium phosphate, Ca3 (PO4) 2. There are numerous accessory constituents, among which vanadium is noteworthy. Some tendency has 

been noted toward enrichment by weathering.

The western phosphate reserve now includes 2,269,055 acres, of which 

664,911 acres is in Idaho. The Idaho portion comprises 268,299 acres 

formally classified as phosphate land and hence released from any form 

of phosphate withdrawal and 396,612 acres unclassified and still remaining withdrawn. There are in addition some privately owned lands. 

The government-owned phosphate land is classified and made available 

for exploitation under regulations which are specified. Not all the reserved land has yet been examined, but 52 townships in Idaho and 6 

townships in Wyoming, which are regarded as phosphate bearing, are 

described in this paper in some detail, and estimates of their tonnages 

are furnished, together with revised estimates of tonnage for other parts 

of the western field. The estimates thus far available for Idaho alone 

indicate a reserve of about 5,000,000,000 tons of high-grade phosphate 

rock.

The history of the western phosphate industry is briefly sketched, including an account of the litigation, its settlement, and the subsequent 

laws affecting phosphate lands. The producing companies are briefly 

described and information is given regarding the production, marketing, 

and utilization of the rock, together with a statement about processes of 

manufacture of phosphate and of phosphorous. Author's summary, chap. 

7, Mineral Resources

27 Mansfield, G. R., 1940, Phosphate deposits of the United States: Econ.

Geology, v. 35, no. 3, p. 405-429.

A variety of types of phosphate deposits, representing a wide range in 

geologic age, are found in the United States. Guanos containing from 4 

to 32 percent P2O5 have been reported chiefly from Texas and New Mexico, 

where they are locally of some commercial importance. Phosphatic marls 

of both Cretaceous and Tertiary age are found in the sedimentary rocks 

of the eastern Coastal Plain; the P2O5 content is low, ranging from less 

than 1 percent to 4.5 percent. Low-grade phosphatic limestones are widely 

distributed in both the eastern and western parts of the United States and 

range in age from Paleozoic to Tertiary. Apatite is a constituent of many 

igneous and metamorphic rocks, but is rarely found in commercial concentrations. The only apatite produced in the United States is from the 

titanium-apatite deposits in Nelson County, Va. Phosphate rock in the 

North Carolina, Georgia, and Alabama fields is of low grade and has not 

been explored extensively. Medium-grade phosphate rock deposits in South 

Carolina were among the greatest sources in the world before the exploitation of the Florida and Tennessee fields. Some phosphate has been produced from the brown-rock phosphate deposits in Kentucky, and from the 

phosphate deposits in the Cason shale of Ordovician age in Arkansas. The 

most important deposits of phosphate rock are found in Florida, Tennessee, 

and the western field.

The principal types of phosphate rock in Florida are the land pebble, 

hard rock, soft rock, and river pebble. The land-pebble phosphate is in 

the marine Bone Valley formation of Pliocene age and is the most im-
50 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

portant commercial deposit of the four types mentioned. The residual 

hard-rock deposits are in the Alachua formation of Pliocene age. Soft 

rock is finely divided phosphatic material and is present in small amounts 

in both the land-pebble and hard-rock fields. River-pebble phosphate, 

mostly of Recent age, occurs as bars and banks in stream channels in the 

adjoining lowlands.

The Tennessee phosphates occur in the western part of the central basin 

of the state and in valleys of the western part of the Highland Rim surrounding the basin The phosphates are of three types: brown, blue, and 

white rock. Brown-rock phosphates are residual deposits derived from 

phosphatic limestone formations of Ordovician age, and are now the most 

important commercially. The blue rock is an unaltered portion of the 

Hardin sandstone member of the Chattanooga shale of basal Mississippiau 

or Late Devonian age. The white-rock deposits are secondary deposits 

formed by solution of phosphatic minerals in the overlying blue rock, and 

by redeposition in openings in the underlying limestone.

The phosphate deposits in the phosphatic shale member of the Permian 

Phosphoria formation in Idaho, Montana, Wyoming, and Utah contain 

the commercial deposits of the western field.

The geology of the deposits and the mining and prospecting methods 

used are discussed briefly; reserves are given for most of the fields.

28 Moxharn, R. M., 1954, Airborne radioactivity surreys for phosphate in 

Florida: U. S. Geol. Survey Circ. 230, 4 p., 9 figs.

Airborne radioactivity surveys totaling 5,600 traverse miles were made 

in 10 areas in Florida, which were thought to be geologically favorable 

for deposits of uraniferous phosphate. Abnormal radioactivity was recorded in 8 of the 10 areas surveyed. The anomalies are located in 

Bradford, Clay, Columbia, De Soto, Dixie, Lake, Marion, Orange, Sumter, 

Taylor, and Union Counties. [Airborne radioactivity survey maps of all 

the areas covered are included In the circular.]

Two of the anomalies were investigated briefly on the ground. One 

resulted from a deposit of river-pebble phosphate in the Peace River 

valley; the river-pebble samples contain an average of 0.013 percent 

equivalent uranium. The other anomaly resulted from outcrops of 

leached phosphatic rock containing as much as 0.016 percent equivalent 

uranium. Several anomalies in other areas were recorded at or near 

localities where phosphate deposits have been reported.

At least two of the airborne radioactivity anomalies described above 

have been caused by deposits of uraniferous phosphatic materials. Most 

of the other anomalies were detected in areas in or near which phosphate 

has been reported, so it would appear that the anomalies are in some 

manner related to uranium associated with phosphatic materials. However, it should be pointed out that, at nearly every locality at which 

phosphate has been reported, the material is said to be covered by as 

much as 50 feet of overburden. If radioactive source rocks of the tenor 

with which we are dealing are covered by more than 1 foot of inert overburden, the radiation intensity should be reduced to an undetectable level 

at the 500-foot flight level. So, if the anomalies described above are to 

be attributed to phosphatic materials, we must assume that (1) the
URANIUM-BEARING PHOSPHORITES IN THE UNITED STATES 51

deposits are at or near the surface of the ground or (2) radioactive materials are being transported to the surface from buried deposits.

The results of the surveys indicate that the phosphate deposits of 

Florida contain sufficient uranium to be detected by airborne radioactivity 

detection equipment provided there is some surface expression of the 

deposits. The significance of the radioactivity anomalies in the areas of 

buried phosphate deposits cannot be ascertained until adequate exploration work is undertaken. Author's abstract

29 Nininger, R. D., 1954, Minerals for atomic energy: 367 p. (See p. 38-39 

and 73-74.), D. Van Nostrand Co., Inc., New York, Toronto, London.

Uranium occurs in marine phosphorites of the western Phosphoria formation and the Bone Valley formation in Florida, and in phosphatic 

nodules of black shales in Oklahoma and Kansas. The uranium in these 

marine phosphates is of syngenetic origin. Nonmarine phosphorites, such 

as those in Tennessee, and the Florida hard-rock phosphates, are not 

appreciably uraniferous.

Uranium-bearing phosphorites range in age from Paleozoic to Pliocene 

and seem to be equally favorable as sources of uranium. Generally, the 

beds with the highest P2O5 content are likely to have the highest uranium 

content, although there are some exceptions. The uranium appears to 

be primarily in the phosphate mineral which is a fluorapatite, although 

some uranium is probably associated with the clay minerals and organic 

material.

The first uranium production from phosphates was in 1952 from the 

central Florida deposits. The Bone Valley formation of Pliocene age is 

the most uraniferous. The underlying Hawthorn formation of Miocene 

age has a lower P2O5 and uranium content than the Bone Valley 

formation.

The Permian Phosphoria formation which crops out in Idaho, Montana, 

Wyoming, and Utah is appreciably uraniferous. The uranium content 

varies from one area to another; it increases, for example, westward from 

Wyoming into Idaho, and decreases westward in Montana. The northwest phosphates contain several minor metals other than uranium.

30 Patton, W. W., Jr., 1955, Phosphate deposits in northern Alaska: U. S. 

Geol. Survey Open-file Kept., 13 p.

Phosphate deposits have been found in the Kiruktagiak River and Tiglukpuk Creek areas in the Brooks Range in northern Alaska. The phosphate beds are in a 40-foot-thick zone of phosphate rock, limestone, and 

mudstone in the upper part of the Lisburne group of Mississippian age.

The phosphate rock is dark grey to black on fresh surfaces, light grey or 

brown on weathered surfaces, and is often coated with a characteristic 

bluish-white bloom. Secondary purple fluorite was noted in veinlets and 

on bedding plane surfaces of the phosphate rock. Phosphate pebbles a 

maximum of one-half inch in diameter are often found on bedding surfaces. The thickness of the phosphorite ranges from a fraction of an 

inch in highly argillaceous rock to 2 feet in highly calcareous rock.

The P2O5 content of the rocks generally ranges from 14 to 32 percent, 

although some samples contain as much as 34 percent. Chemical analyses
52 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

indicate a maximum of 0.024 percent equivalent uranium and 0.02 percent 

uranium.5

Detailed stratigraphic sections and chemical analyses (P2O5 only) are 

given for Monotis Creek in the Kiruktagiak River area and for Skimo Creek 

in the Tiglukpuk Creek area.

31 Runnels, R. T., Schleicher, J. A., and Van Nortwick, H. S., 1953, Composition of some uranium-bearing phosphate nodules from Kansas 

shales: Kans. State Geol. Survey Bull. 102, Pt. 3, p. 93-104.

This report discusses samples of uranium-bearing phosphate nodules 

taken from seven different shale beds of Pennsylvanian age in Kansas. 

The localities examined are in Wyandotte, Labette, Linn, Crawford, 

Douglas, and Wilson Counties. The shales examined are listed below, 

in ascending order, and some are described briefly.

Shale from the Cherokee group: A black, fissile shale a few feet above 

the Mulky coal and below the Fort Scott limestone. Round to oval 

phosphate concretions are abundant throughout.

Little Osage shale member of the Fort Scott limestone.

Anna shale member of the Pawnee limestone: The shale occurs just 

below the Myrick Station limestone member. The phosphate nodules 

have a higL purity (34 percent P2O3 ) and a high uranium content (0.02 

percent U3O8 ).

Lake Neosho shale member of the Altamont limestone.

Shale of the Pleasanton group: The shale has a consistent black fissile 

bituminous facies. The top 18 feet is barren of nodules in contrast to the 

underlying 10 feet which contains abundant nodules. The phosphatic 

nodules of this group differ slightly from those in other groups in that 

many of these have a core of iron sulfide.

Muncie Creek shale member of the lola limestone: Some nodules from 

this shale have very high contents of P2O5 (37 percent) and U3OS (0.03 percent). There is evidence [not given] that these nodules have been reworked and probably redeposited during final deposition and initial compaction of the shale.

Heebner shale member of the Oread limestone: This is a persistent black 

shale occurring between the Plattsmouth and Leavenworth limestone members. The nodules are generally well formed and numerous. According 

to the author the phosphate content is fairly high (32 percent PaC^s), although the uranium content is not anomalous (0.017 percent U3O8 ).

The average composition of the phosphatic nodules is 30.2 percent P2O5 , 

0.017 percent UsOg, and 3.2 percent F. The mineral form has tentatively 

been identified as a carbonate-bearing fluorapatite, which is chemically 

between fluorapatite and dahlite. The X-ray diffraction patterns suggest 

a single carbonate-fluorapatite mineral, but the sedimentary origin of the 

nodules points to the possibility of the presence of dahlite.

5 Mateko, J. J., 1953, Reconnaissance for uranium in Alaska ; in Geologic investigations of 

radioactive deposits, Semiannual progress report, June 1 to November 30, 1953 : U. S. Geol. 

Survey Kept. TEI-390, p. 224 ; issued by U. S. Atomic Energy Comm., Tech. Inf. Service, 

Oak Ridge, Tenn.

Matzko, J. J., 1954, Reconnaissance for uranium in Alaska ; in Geologic investigations 

of radioactive deposits, Semiannual progress report, December 1, 1953, to May 31, 1954: 

U. S. Geol. Survey Rept. TEI-440, p. 187 ; issued by U. S. Atomic Energy Comm., Tech. Inf. 

Service, Oak Ridge, Tenn.
URANIUM-BEARING PHOSPHORITES IN THE UNITED STATES 53

The phosphate nodules may be a potential source of fertilizer because 

their phosphate content is comparable to that of commercial rock phosphate. The potential value of the uranium is unknown.

32 Russell, W. L., 1944, The total gamma ray activity of sedimentary rocks 

as determined by Geiger counter determinations: Geophysics, v. 9, 

no. 2, p. 180-216.

This report presents in table form the radioactivity of 510 samples of 

sedimentary rocks including shales, limestones, sandstones, and dolomites. 

Results are given for formations in Arkansas, Kansas, and Oklahoma that 

contain phosphatic nodules. The reference has been included because it 

is one of the few publications that give the results of radioactivity determinations of these rocks.

33 Swanson, II. W., McKelvey, V. E., and Sheldon, R. P., 1953, Progress 

report on investigations of western phosphate deposits: U. S. Geol. 

Survey Circ. 297, 16 p.

A comprehensive investigation of the western phosphate deposits has 

been in progress since 1947. Most of the field work is now completed 

but final reports will not be completed for some years. The scope of the 

investigations and preliminary conclusions, however, are summarized in 

this report.

The principal phosphate deposits are found in the Phosphoria and Park 

City formations over an area of about 135,000 square miles in Montana, 

Idaho, Wyoming, and Utah. The rocks composing these formations in the 

western part of the field are chiefly dark phosphatic shales and cherts that 

were deposited near the margin of the Paleozoic Cordilleran miogeosyncline; those to the east are thinner, Avere deposited on the stable continental 

platform, and include conspicuous limestones and sandstone that grade 

eastward into redbeds in Wyoming and Utah. Complex structures characterized by parallel-trending tight folds and thrust faults were developed 

subsequently in the area of the miogeosyncline, whereas simpler structures 

characterized by random orientation were developed in the platform area.

Two black phosphatic shale members characterize the Phosphoria formation. The lower and more important of these members is thickest 

and most phosphatic in southeast Idaho and pinches out in southern 

Montana, central Wyoming, and eastern Utah. The upper member is 

best developed in southwestern Montana but is prominent also in western 

Wyoming. Chert characterizes the intervening member, but limestone 

and sandstone are important constituents to the north and east. Also 

toward the north and east, chert and sandstone above the upper phosphatic 

shale are important.

The Bear River region of southeastern Idaho and adjacent parts of 

Wyoming and Utah contains the greatest total amount of phosphate as 

well as the thickest beds of high-grade phosphate, although some highgrade beds of mineable thickness occur in other parts of the field, particularly in western Montana. Several valuable deposits were discovered 

during this investigation, most noteworthy of which are a 6-foot bed 

of acid-grade rock in the Centennial Mountains at the Montana-Idaho 

State line, a 12-foot bed of 33 percent P2O3 rock in the Caribou Range, 

Idaho, several strippable deposits of acid- and furnace-grade rock in 

southeastern Idaho, and a 12-foot bed of 20 percent P2O3 rock at the top 

of the formation north of Cokeville, Wyoming. Authors' abstract
54 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

34 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 were analyzed radiometrically for uranium, 

and chemically for PZO5, C'aO, 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, 

PzO-5, 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 P2Os 

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

35 Thompson, M. E., 1954, Further studies of the distribution of uranium in 

rich phosphate beds of the Phosphoria formation: U. S. Geol. Survey 

Bull. 1009-D, p. 107-123.

Rock from the Phosphoria formation is pelletal rather than oolitic, and 

is generally dark brown to black. The phosphatic material is chiefly 

pelletal phosphate of the carbonate-fluorapatite type.

The five sets of close samples (narrow and contiguous samples across a 

lithologic unit) from Idaho, Wyoming, and Utah, which are described in 

the preceding article by this author (ref. 34), were also analyzed chemically for F and CO2 in an effort to determine whether there is any correlation between these constituents and equivalent U and P2O5. The formula 

used for the coefficient of correlation is that given by Snedecor."

The samples with a high percentage of equivalent uranium show much 

better correlation of equivalent uranium with P2O5 than do the samples of 

a low percentage of equivalent uranium. The samples that show good correlation of equivalent uranium with P2O6 show better correlation of CO2 

with P2O5.

The size of the phosphorite pellets was measured in the thin sections of 

two sets of samples. This was done in an effort to determine whether or 

not the size of the pellets in phosphate rock might have a direct relation 

to the amount of uranium present. Cumulative curves and frequency 

histograms were plotted from the size measurements obtained. Comparison of these with the uranium concentration for each sample did not show 

a significant correlation between size of phosphorite pellets and amount of 

uranium.

36 Anonymous, 1950, Uranium found in Florida phosphate limited to certain

deposits: Eng. Min. Jour., v. 151, no. 8, p. 93.

Land-pebble phosphate, hard-rock phosphate, and river-pebble phosphate 

are the three types of phosphatic rock found in Florida. Mr. Oathcart's 

report is concerned primarily with the land-pebble deposits, the only type 

which contains the uranium. The most productive part of the land-pebble 

district is in Polk and Hillsborough Counties, in the west-central part of 

Florida.

8 Snedecor, G. W., 1946, Satistical methods applied to experiments in agriculture and 

biology: Iowa State Coll. Press, p. 138.
URANIUM-BEARING PHOSPHORITES IN THE UNITED STATES 55

In the two counties named, which contain the high-grade part of the 

land-pebble phosphate district, iiranium occurs principally in the Bone Valley formation. Fresh unweathered Hawthorn formation has little or no 

uranium, but leached Hawthorn, rich in P2O5, contains a small amount of 

uranium. The Pleistocene sands have no uranium except where they contain reworked phosphatic material from the Bone Valley formatio

South of the high-grade district, in Manatee and Hardee Count 

Bone Valley, Hawthorn, and Pleistocene formations contain onl 

minor amounts of uranium.

The uranium in the land-pebble deposits was probably syngenetic 

gin. The uranium seems to be associated with the phosphate.

Two types of rocks in the land-pebble phosphate district conta 

uranium. First is the rock composed of sand, clay, and abundan 

phate nodules, termed "matrix." Uranium is present in nodules as 

by analyses of samples from which everything but the phosphate i 

have been removed. In this case it is possible that the uranium ta 

place of the calcium in the phosphate mineral. Uranium is also 

in the clay fraction (slime). Certain rocks which are composed 

sized particles and are white and kaolin-like and highly phosphat 

contain small amounts of uranium. Green "matrix" clays, howev 

tain almost no phosphate, and little or no uranium. Resume of a 

J. B. Catlicart (U. 8. Geol. Survey)

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INDEXES

AUTHORS

Reference No.

Altschuler, Z. S______________ 1-3, 22 

Arnold, B. P_______________ 16 

Atkin, D___________________ 12 

Barnes, V. E______________ 4 

Bergendahl, M. H____________ 5 

Blade, L. V_______________ 11 

Buck, K. L_________________ 22 

Carswell, L. D______________ 6, 21 

Cathcart, J. B__________ 7-11, 22, 36 

Clark, R. S., Jr_____________ 2 

Cuttita, Frank_____________ 3 

Davidson, C. F_________-___ 12 

Davidson, D. F_____________ 11,16 

Dietz, R. S_________________ 13, 14 

Emery, K. O______________ 13,14 

Gould, H. R________________ 15 

Harris, R. A______________ 16 

Hill, W. L__________________ 17 

Jacob, K. D________________ 17 

Jaffe, E. B________________ 3

Reference No.

Ketner, K. B_______________ 11,18 

Klemic, Harry______________ 25 

McKelvey, V. E__________ 6, 19-23, 33 

McKeown, F. A______________ 25 

Mansfield, G. R_____________ 26,27 

Marshall, H. L_____________ 17 

Moxham, R. M______________ 28 

Nelson, J. M_______________ 23 

Nininger, R. D___________ 29 

Patton, W. W., Jr_ __________ 30 

Reynolds, D. S________________ 17

Runnels, R. T ___ _ 31 

Russell, W. L_____ 32

Schleicher, J. A_____________ 31 

Sheldon, R. P_____________ __ 24,33

Shepard, F. P___________ 13 

Swanson, R. W_____________ 22,33 

Thompson, M. E_ 34, 35 

Van Nortwick, H. S____________ 31

Young, E. J___________________ 2

GEOGRAPHIC AREAS

Reference No. 

United States

Alabama ________________ 22,27

Alaska _________________ 30

Arkansas

Phosphate field________ 22, 27, 32

California

Offshore phosphorites 13,14

Florida

Bradford County__________ 28 

Clay County-____________ 9, 28 

Columbia County_________ 28 

De Soto County_____ _ _ 28 

Dixie County____________ 28 

Hardee County _____-___ 36 

Hard rock phosphate field__ 7,17, 27 

Hillsborough County______ 1,10, 36 

Lake County___^_________ 28

Land-pebble phosphate district_ 3,10,

11, 23, 27, 29, 36

Manatee County _______ 9

Marion County ___________ 9, 28 

Orange County________ _ 28 

Peace River area_______ _ 3, 8 

Polk County____________ 1, 10, 36 

Steinhatchee area___ __ 9 

Sumter County__________ 28 

Taylor County___________ 28 

Union County ____________ 9, 28

Reference No.

United States Continued

Georgia ____ 9, 22. 27

Altamaha River drainage__ 9

Gulf of Mexico, eastern_______ 15

Idaho _____________ 6, 21-24, 26,

27.29,33-35

Kansas ______________ 23, 29, 31, 32 

Kentucky ______________ _ 22, 27 

Montana __________ 21-24, 27, 29, 33 

New Jersey- _ - 25 

New Mexico_______ _ 22,27 

New York_____________ __ 25 

North Carolina______________ 22, 27

Oklahoma _______________ 23,29 

South Carolina _______ 12, 17, 22, 27 

South Dakota_______ 2 

Tennessee __.._____ _ 17, 22, 27 

Texas ______ _ 4, 27 

Utah __________ 21-24, 27, 29, 34-35 

Virginia __________________ 22, 27 

Western phosphate field_______ 6,16,17,

21-24, 26-27, 29, 33-35 

Wyoming _______ 21-24, 27, 29, 33-35

Others

Europe 12 

Great Britain___________ _ 12 

North Africa__________ 12 

Oceanic islands ____ 12

57
58 SELECTED BIBLIOGRAPHIES OF URANIUM GEOLOGY

GENERAL

Reference No.

Alachua formation __ _____ 27 

Aluminum phosphate_____ 1, 3, 8,10, 11 

Apatite deposits ___________ 22, 25, 27 

Altamont limestone, Lake Neosho

shale member______ 31

Barnet formation _ _ _ 4

Bibliographies _____________ 16, 18

Bone Valley formation______ 3, 5, 7, 10,

11, 23, 27, 29, 36

Cason shale_ ___ __ _ 27 

Chattanooga shale, Hardin sandstone

member _________ 27 

Cherokee group_____________ 31 

Cofleyville formation, checkerboard

limestone member___ 23 

Fort Scott limestone, Little Osage

member _________ 31 

Fossil bones _______________ 2,12

Guano __________________ 22, 27

Hawthorn formation______ 10, 11, 29, 36

Hushpuckney shale_ _ _ 23 

lola limestone, Muncie Creek member ____________ 31

Reference No.

Land-pebble deposits 1, 3, 7, 8, 

10,11, 23, 27, 29, 36

Lisburne group _ _ _ 30 

Marble Falls formation________ 4 

Oread limestone, Heebner shale member _____________ 31 

Pawnee limestone, Anna shale member ____________ 31 

Phosphate reserves _ 17, 22, 27 

Phosphoria formation. 21-24, 27, 29, 33-35 

Phosphorites, marine _ __ 1-11,13-15, 

17, 19, 21-24, 26-36

residual __________ 17,19,22,27 

Phosphatized rock_ _ ___ 7,17, 22, 27 

Pleasanton group 31 

Radioactivity, anomalous 9, 28 

Radioactivity, determinations of 32 

River pebble deposits__________ 22, 27 

Stark shale. __ _ 23 

Tampa formation- __ _ 10 

Wavellite sperulites 5

o