Field conference on kaolin and fuller's earth, November 14-16, 1974 [1974]

FIELD CONFERENCE ON KAOLIN AND FULLER'S EARTH
NOVEMBER 14-16, 1974 by
S. H. Patterson and B. F. Buie
GUIDEBOOK 14
Published by the Georgia Geological Survey for the Society of Economic Geologists
Georgia Department of Natural Resources Joe D. Tanner, Commissioner Earth and Water Division The Geological Survey Sam M. Pickering, Jr., Director

.I

FIELD CONFERENCE ON KAOLIN AND FULLER'S EARTH NOVEMBER 14-16, 1974
by S. H. Patterson U. S. Geological Survey National Center Reston, Virginia
and B. F. Buie Department of Geology Florida State University Tallahassee, Florida
for
THE SOCIETY OF ECONOMIC GEOLOGISTS, INC.
Published by the Georgia Geological Survey ATLANTA 1974

CONTENTS Page

Part 1-Kaolin of the Macon-Gordon area

1

Introduction

1

Geology . . . . . . . . .

1

Stratigraphy. . . . . .

1

Pre-Cretaceous rocks

1

Cretaceous to middle Eocene strata .

1

Strata of late Eocene age .

4

Structure . . . . . . . . .

5

Kaolin deposits . . . . . .

5

Definition and mineralogy

5

Occurrence . . . . . .

7

Origin . . . . . . . .

7

Exploration and evaluation of deposits

9

Preparation of kaolin for market .

9

Mining. . . . . . . . .

9

Beneficiation . . . . . .

9

Kaolin uses and production .

11

Field trip-Kaolin in the Macon-Gordon area, November 15, 1974

15

Part II-Fuller's earth of the Meigs-Attapulgus-Quincy district, Georgia and

Florida. . . . .

23

Introduction

23

Geology . .

23

Stratigraphy .

23

Hawthorn Formation

23

Miccosukee Formation as used by Hendry and Yon (1967)

27

Structure . . . . . . . . . . . . . .

28

Regional structure of the Coastal Plain

28

Gulf trough, a structural feature (?)

28

Fuller's earth deposits

29

Definition

29

Mineralogy . . .

29

Clay minerals

29

Detrital nonclay minerals

31

Authigenic and diagenic nonclay minerals

31

Occurrence . . . . . . . . .

33

Origin . . . . . . . . . . .

33

Preparation of fuller's earth for market

37

Mining . .

37

Processing

37

Uses. . .

37

Production

39

Field trip-Fuller's earth in the Meigs-Attapulgus-Quincy district, November

16, 1974 .

41

References cited

49

iii

Page

Figure 1. Kaolin and bauxite districts in the Coastal Plain of Southeastern United

States . . . . . . . . . . . . .

2

2. Electron micrograph of Georgia kaolin

6

3. Flow diagram of kaolin beneficiation .

10

4. Graph showing kaolin sold or used by producers for specific uses, 1929-

1971 . . . . . . . . . . . . . . . . . . . .

12

5. Route and stops of kaolin field trip-Gordon and vicinity

16

6. Route and stops of kaolin field trip-J. M. Huber Corp. mining area

20

7. Location of Meigs-Attapu{gus-Quincy district, Georgia and Florida

24

8. Generalized section of the rocks exposed in the Meigs-Attapulgus-

Quincy district

. . . . . .

. . . . . . . . 25

9. Thickness of Miocene to Holocene sediments in Gulf Trough in south-

western Georgia, modified from Herrick and Vorhis (1963, Fig. 2) .

28

10. Electron micrograph of palygorskite (attapulgite) fuller's earth .

30

11. Photomicrograph of powder mount of dolomite in fuller's earth

32

12. Graph showing fuller's earth sold or used by producers for specified

uses, 1927-1971, compiled from U.S. Bureau of Mines Minerals

Yearbook . . . . . . . . . . . .

38

13. Route and stops of fuller's earth field trip

42

iv

FOREWORD
This guidebook was prepared for a field conference sponsored by the Society of Economic Geologists (S.E.G.), Inc., prior to the joint meeting of S.E.G. with the Geological Society of America, Miami, Fla., 1974. The conference includes an orientation session in the evening of November 14, a field trip in the Macon-Gordon area of the Irwinton, Ga. kaolin district on November 15, and a trip to the Meigs-Attapulgus-Quincy fuller's earth district, Georgia-Florida, on November 16.
ACKNOWLEDGMENTS Many professional and management personnel aided the authors in many ways during the preparation of this guidebook, including granting access to mines and plants and advice on conducting the field trips. Among those to whom we wish to express our thanks are John M. Smith and Doral Mills of Georgia Kaolin Co.; Fred Gunn, Paul Sennett, and Joe H. Mackenzie, Jr. of Freeport Kaolin Co.; Jack Rogers, E. F. Oxford, Tijs Volker, and Ralph B. Hall of J. M. Huber Corp.; Barry Reid of Cyprus Industrial Minerals Co.; Robert P. Smith of Waverly Mineral Products Co.; R. C. Valenta, Richard M. Jaffee, and Richard Chapman of Oil-Dri Corporation of America; Jack W. Williamson of Englehard Minerals and Chemicals Corporation; Doyle Croston and Larry Otwell of Thor Mining and Floridin Companies (Pennsylvania Glass Sand, Inc.); H. H. Morris, Macon, Ga., former Vice-President, Research and Development, Freeport Kaolin Co., and now consultant in the paper and paperboard fields. The senior author would be remiss if he did not acknowledge that part of his contribution was possible only because of knowledge he acquired while jointly writing the clay chapter for the 4th edition of AIME's Industrial Minerals and Rocks with Haydn H. Murray of Indiana University. Special thanks are due Sam M. Pickering, Jr., the State Geologist of Georgia for his support of this conference and for making the publication of this guidebook possible.
v

PART I - KAOLIN OF THE MACON-GORDON AREA1
INTRODUCTION
The kaolin deposits in the Macon-Gordon area, Georgia, with which the first part of this field conference is concerned, are in the southwestern one-half of the Irwinton district (Fig. 1). They are part of a belt of kaolin districts extending along the inner edge of the Coastal Plain from the Aiken district, South Carolina, southwestward to the vicmity of Macon, a distance of about 150 miles (240 km). Large kaolin deposits associated with bauxite also occur in an extension of the belt as far as the Eufaula district, Alabama, approximately 130 miles (208 km) southwest of the Macon-Gordon area. The belt splits away from the inner edge of the Coastal Plain in a southwesterly direction from Macon, and the Eufaula district is approximately 50 miles (80 km) south of the contact of Coastal Plain sedimentary rocks and the much older crystalline rocks.
The Macon-Gordon area is bounded on the southwest by the Ocmulgee River, and it extends eastward to the vicinity of Gordon, Ga. This eastern boundary is established for the purposes of this conference only as a practical limit for a 1-day field trip. Other large kaolin deposits, mines, and several plants are located farther east in the Irwinton district in the vicinities of Mcintyre, Irwinton, Deepstep, and Sandersville.
GEOLOGY STRATIGRAPHY
PRE-CRETACEOUS ROCKS
The rocks of pre-Cretaceous age in the Piedmont Province that occur in the region landward from the Coastal Plain are dominantly schist, gneiss, dnd quartzite; also present is a variety of other igneous rocks. These rocks were formerly thought to be of Precambrian age. Most of the metamorphic rocks are now known to be Paleozoic, and many are of probable late Paleozoic age. Some of the igneous bodies are of Triassic to Jurassic age. Most of the rocks exposed in the Piedmont Province are deeply weathered.
CRETACEOUS TO MIDDLE EOCENE STRATA
The kaolin deposits occur in sedimentary beds that overlap and lie unconformably on much older crystalline rocks. All of the kaolin deposits in the Macon-Gordon area were thought for decades to be of Cretaceous age, but many are now known to be younger. The Cretaceous formations in west-central Georgia and Alabama consist chiefly of marine sediments. These formations have not been traced with certainty east of the Ocmulgee River. This is mainly because of the absence of prominent lithologic differences and other criteria for distinguishing units and recognizing contacts where marine formations grade laterally into beds having nonmarine characteristics. The Cretaceous strata in the MaconGordon area consist chiefly of white and buff, crossbedded, irregular and channel-fill deposits of medium- to very coarse-grained, subrounded to angular quartz sand. Interstitial kaolin and white mica flakes are common in these beds. The beds also contain the large valuable kaolin deposits, and some of these, or at least some formerly thought to be of Cretaceous age, contain small gibbsitic bauxite deposits. Some of these bauxites were mined and used for aluminum in the early part of this century, and a few have been mined more recently for use in refractory products.
1 Approved for publication by the Director, U.S. Geological Survey.

0 0

100 MILES 100 KILOMETERS

~{ EXPLANATION
~ Wilcox group, undivided
r~ : n
Post-Tuscaloosa Cretaceous strata
~ ~
Tuscaloosa Group or
-Formation, undivided
Kaolin or bauxite district 1, Aiken, S. C. 2, Wrens, Ga. 3, Irwinton, Ga. 4, Andersonville, Ga. 5, Sprin1vale, Ga. 6, Eufaula, Ala.
Boundary of major physio(raphic province
Formation boundary

Figure 1. Kaolin and bauxite districts in the Coastal Plain of Southeastern United States. 2

Beds formerly included in the Cretaceous are probably as much as 700 or 800 feet (213 to 243m) thick (in the subsurface), but continuous natural exposures having a thickness of more than 50 feet (16m) are rare. Though these beds have nonmarine characteristics in the Macon-Gordon area, they grade in a seaward direction into beds 'containing marine fossils. East of the Ocmulgee River, all beds in Georgia formerly thought to be of Cretaceous age have been mapped as "Cretaceous undifferentiated" or as the Tuscaloosa Formation following Cooke's (1943) usage of the term. A shortcoming of the name "Tuscaloosa" in this area is that this formation farther southwest is only the basal one of six Upper Cretaceous formations. Recent studies of spores, pollen, invertebrate fossils, and foraminifera, in and associated with kaolin indicate that many of the deposits thought to be Cretaceous are of Eocene age (Buie and Fountain, 1968; Pickering, 1971; Scrudato and Bond, 1972; Cousminer and Terris, 1973; Cousiminer, 1973), a possibility suggested by Eargle (1955). The first announcement of the Eocene age for any of the deposits was by Buie and Fountain, who on the basis of paleontological evidence, established the presence of middle Eocene strata beneath some of the commercial kaolin deposits and above others. In one of the studies, Cousminer and Terris concluded through palynological work that some, if not all, of the sedimentary kaolin is middle Eocene in age. Results of palynological studies by R. H. Tschudy of the U. S. Geological Survey have confirmed that some of the kaolin deposits are of Late Cretaceous age or older, and that some are not older than Claiborne (middle Eocene). Tschudy's work also revealed that sand beds of Paleocene age are present in the kaolin belt. This raises the possibility that some of the kaolin deposits may be of Paleocene age and that kaolin deposition took place during several different intervals of geologic time.
The fauna that B. F. Buie discovered in sand associated with kaolin deposits consisted of external molds of small pelecypods and gastropods. Using the latex-cast technique, Dr. L. D. Toulmin (written commun., 1964) identified the fossils and determined that they are Claiborne (middle Eocene) or Jackson (late Eocene) in age. Toulmin's memorandum states:
"The external molds of mollusks are in poorly sorted medium- to coarsegrained quartz sand. The sand grains are held together by a small proportion of Kaolin. The stratigraphic relationship of this bed and the Moodys Branch Formation is not known. 1 The Moodys Branch Formation2 in eastern Georgia is chiefly sandy limestone and contains the fossils Periarchus lyelli and Crassostrea gigantissima. It is not known to contain a large number of molluscan species east of western Alabama.
"It is difficult to determine species from fossil molds, and the bed containing the molds may be either the equivalent of the Gosport Sand or the lower part of the Moodys Branch (Dellet Sand of Stenzel) from the genera recognized. It is faunally and lithologically different from any Moodys Branch beds I have seen in Georgia and therefore may be Gosport. Its stratigraphic relationship with the Moodys, if determinable, would be a better criterion of its age than the genera recognized. The fossils are Nucula probably ouula, Nuculana, Pitar?, Crassatella, Linga pomilia alueata, Dentalium thalloides?, Mesalia uetusta ~. Turritella.
1 The bed of fossil molds is now known to lie stratigraphically below the beds equivalent to the Moodys Branch and is separated from them by a disconformity.
2 Pickering includes the beds equivalent to the Moodys Branch Formation in the Clinchfield Sand, a formation recently defined by him" (Footnotes were added by L.D.T. in 1971 after studying the formation in the field)
As the beds containing these fossils are consistently below a clearly defined unconformity at or near the base of typical Jackson strata, it is logical to consider the fossil-bearing strata to be Claiborne in age.
The evidence, based on identifications of Foraminifera, that some of the kaolin is Tertiary in age was reported by Pickering (1971). He outlined his findings as follows:
"In the fall of 1971, the writer found a number of sediment balls embedded in a thin lens of kaolin in the Georgia Kaolin Company 59 B mine (Stop 4). Bryozoa were observed in one of the sediment balls, and a small
3

portion of it was collected and prepared for microfossil analysis. Well-preserved bryozoa, foraminifera (tentatively Textularia sp., Nonion inexcavatus, Eponides jacksonensis, Cibicides lobatulus, Cibicides americanus antiquus, Discorbis assulatus, and Valvulineria jacksonensis) and ostracodes were noted. The above mentioned foraminifera indicate an Eocene age for the sediment ball, and by inference, the kaolin lens, corroborating the evidence of Buie and Fountain."
The palynological evidence which the authors use in support of the conclusion that kaolins of both Cretaceous and Tertiary ages are present in the Macon-Gordon area is mainly the finding of R. H. Tschudy (written commun., 1974) of the U.S. Geological Survey. His determinations of ages were based on several suites of palynomorphs and other microfossils. Among those on which the Late Cretaceous (Maestrichtian) determination is based is Rugubivesiculites. The Paleocene ages were based on the presence of several genera and species reported in formations of this age in the Mississippi Embayment region. The Wilcox age was assigned to material containing Carya and Thomsonipollis. A definite middle Eocene (Claiborne) age was indicated for samples of black clay containing Platycarya, Nudopollis of the terminalis type, Tricolporopollinites (fusoid forms), and Cyrillaceaepollinites cf. C. megaexactus.
The observation and conclusion that part of the kaolin and associated beds formerly assigned to the Tuscaloosa Formation are considerably younger leads to the problem of how to distinguish the Cretaceous beds from those of Tertiary age and what criteria to apply in the recognition of new formations or other stratigraphic units. The difficulties are increased by the presence of numerous lenticular units, channel-fill deposits, and irregular and gradational contacts between lithologic units. Nevertheless, a widespread unconformity at the top of kaolin deposits of Cretaceous age or a short interval above them generally can be recognized where good exposures are present. Such a contact and adequate accurate elevations of it should permit the preparation of improved geologic maps on which the Tuscaloosa Formation of former usage is subdivided into such units as "strata of Late Cretaceous age" and "beds of Paleocene to middle Eocene age."
The strata above the probable post-Cretaceous unconformity, in the updip parts of the Macon-Gordon area, have a characteristic lithology and other features by which they can be distinguished from other beds, and they serve as a guide to the recognition of the unconformity. These strata, which are as much as 50 feet (15.2 m) thick, are at least in part equivalent to a unit other authors have called the "channel sands.:: Though the lower few feet of this unit commonly contain interlayered clays and sand in more or less horizontal beds, most of it is characterized by prominent crossbedding, channel-fill deposits, abundant clay balls or boulders, and small lenticular kaolin masses. The unit consists mainly of unconsolidated sandstone, the grains ranging in size from fine sand to gravel. Most of the quartz is "rotten" and will crumble with slight pressure. Dark, fine-grained heavy minerals are ordinarily abundant along bedding planes.
The sequence of beds between the Cretaceous strata and those of Jackson (late Eocene) age thicken downdip, and they are as much as 90 feet (27m) thick in the central part of Twiggs County. Like some of their updip counterparts the downdip strata are typical of beds deposited in a high energy environment. The lower one-half or two-thirds of the downdip strata contains coarser sand and abundant gravel and thicker and larger channel fillings than does most of the updip part. The upper part of the downdip strata contain evidence of quiet marshy conditions of sedimentation as indicated by scattered deposits of lignitic and black organic-rich clays as well as extensive deposits of commercial kaolin. Some of these kaolin deposits are more than 40 feet thick.
STRATA OF LATE EOCENE AGE
The beds above the kaolin deposits of Claiborne age have predominately marine characteristics, and have been assigned to the Barnwell Formation by some authors. The Jackson (upper Eocene) beds include clay, sand, and limestone occurring as concretions and thin beds, and calcite-cemented sand. They contain a wide variety of marine macro- and microfossils. Burrows of littoral animals called Halymenites or the diggings of Callianassa
4

are common, particularly in the sandy beds. One rather prominent characteristic of the Jackson clayey beds in fresh exposures is a greenish color, which contrasts with the white, gray, and brown colors of the underlying Claiborne sandy beds. This greenish color, though subdued, is nevertheless more pronounced than the greenish tinge of the kaolins of Tertiary age. The sand beds of Jackson age commonly are yellowish green where freshly exposed, and this characteristic aids in their recognition.
Where the Twiggs Clay or similar clays are the lowermost beds of the Jackson Group, the contact between the Jackson and Claiborne rocks can be recognized even in most weathered outcrops. However, the distinction between these two groups is difficult if not impossible where beds of both groups consist of thoroughly weathered sand.
STRUCTURE
The strata of Cretaceous and Tertiary ages containing the kaolin deposits all dip gently seaward from the landward edge of the sedimentary rocks. The dip of the Cretaceous strata is about 25 feet per mile (4.9 m per km). The dip of Tertiary strata is about 15 feet per mile (2.1 m per km). In places, the Tertiary strata overlap the older sedimentary beds and rest directly on the crystalline rocks. Faults having a few feet of displacement have been observed in several mines, but no major faulting is known in the area.
KAOLIN DEPOSITS
DEFINITION AND MINERALOGY
Kaolin when applied as a term for an economic mineral commodity is a clay consisting of substantially pure kaolinite, or related clay minerals, which is naturally white or nearly white or can be beneficiated to this color, will fire white or nearly white, and is amenable to beneficiation by known methods to make it suitable for use in whiteware, paper, rubber, paint, and similar uses. Most of the kaolin deposits mined in Georgia are essentially pure, but for most products, they require washing and degritting or air floating during preparation for market. Most are also slightly off-color, and for several uses they require leaching to recover marketable kaolin. Some kaolin used in refractory products was formerly calcined. Raw kaolin is added to a mix including other raw material in making firebrick. The kaolin used in portland cement is also mixed with other materials and fired.
The structure of kaolinite consists of an alumina octahedral sheet and a silica tetrahedral sheet that form triclinic equidimensional crystals. The theoretical formula of kaolinite is (OH)s Si4 Al4 0 10 , and the theoretical composition is 46.54 percent Si02, 39.5 percent Al2 0 3 , and 13.96 percent H2 0. Kaolinite has relatively little ionic substitution in the mineral lattice, although there is evidence suggesting minor substitution of iron for aluminum in some kaolinite. The perfection or degree of ordering of kaolinite crystals varies considerably. The crystallinity of Georgia kaolin ranges from poorly ordered to very well ordered forms. The more perfectly ordered forms of kaolinite commonly occur in hexagonal or subhexagonal crystals. Growths of crystals along the c-axis into accordionlike or vermicular forms are also common (Fig. 2).
Georgia kaolin ranges from very sandy clay to clay that is essentially pure. Most kaolin mined is more than 90 percent kaolinite. Sand-sized quartz is the principal impurity. Other minerals occurring in minor quantities include muscovite, biotite, smectite (montmorillonite), ilmenite, anatase, rutile, leucoxene, and goethite. Trace amounts of zircon, tourmaline, kyanite, and graphite are also present in some deposits. The presence of a few percent of smectite increases the viscosity of the clay-water mixtures and precludes its use for paper coating.
5

Figure 2. Electron micrographs of Georgia kaolin. Micrographs were made in the SEM Laboratory of Florida State University.
6

OCCURRENCE
Most kaolin is soft and plastic when natural moisture is present or where water has been added to dried material. One way of describing the natural texture is by the colloquial phrase-a good whittling clay-which refers to the ease with which the clay can be carved with a knife. Dry kaolin is ordinarily friable, and a common but not a diagnostic test for it is its stickiness when touched to the tongue. Some types of kaolin, occurring farther east than Gordon, apparently contain introduced silica and are hard and are sometimes referred to as flint kaolin. Though much more lithified than plastic varieties, this so-called flint kaolin is softer than most flint clay, which is widespread in fire-clay deposits of Pennsylvanian age.
The kaolin deposits occur as tabular lenses and discontinuous beds, and their shapes and lateral extent vary appreciably. Some deposits are as much as 60 feet thick, and others have been found to extend laterally for more than a mile.
Two general types of kaolin, the so-called "soft" and "hard" types, have been recognized in the kaolin industry, though use of the terms is not entirely consistent. There are many problemmatical deposits, but many of the soft kaolins are now thought to be Cretaceous and the hard ones Tertiary in age. In addition to the paleontologic evidence for the recognition of kaolin of different ages, the two types commonly can be distinguished by the following characteristics: (1) The hard kaolins ordinarily occur stratigraphically higher than the soft ones. (2) The Cretaceous kaolins are generally coarser grained and contain appreciably more vermicular crystal growths than the Tertiary ones. (3) Titanium, chiefly in the form of anatase, tends to be more abundant in the Tertiary than in the Cretaceous kaolins. (4) Most of the Tertiary kaolins have on a freshly broken surface a very slight green tinge which changes to pinkish after exposure to air for a few days. The white Cretaceous clays show no such color change. (5) The hard kaolin deposits commonly contain abundant small tubular structures; such features are absent in the soft kaolins. Some of these tubular structures resemble bryozoa, and others appear to be borings of some form of marine or littoral animal.
ORIGIN
Strange as it may seem, the kaolin deposits in the extensive belt in Georgia and South Carolina, which have been studied by many geologists and mineralogists and which lead the world as a source of commercial kaolin, are among the kaolins whose origins are least understood. Virtually all who have investigated these deposits agree that either the kaolin or the material form which it formed has been transported. Areas of disagreement center about explanations of how such very large deposits of fine-grained white clay could have formed in environments in which most of the sediments being deposited consisted of sand. Furthermore, an adequate explanation of origin of the deposits must account for the following facts: (1) some deposits of kaolin are finer grained than others; (2) some contain abundant vermicular kaolinite crystals, and some do not; (3) some of the vermicular crystals are very long and slender and must have formed in place; (4) gibbsite is present in some deposits and not in others; (5) lignitic layers or layers rich in organic matter are present in some deposits; and (6) smectite (montmorillonite) is present in some deposits in variable quantities. The deposition or formation of kaolin deposits in Late Cretaceous time and again in at least one interval of Eocene time must also be accounted for.
One of the first geologic studies of the Georgia kaolin was by Ladd (1898); he described the deposits but did not discuss their origin. Veatch (1909) concluded that the lowermost unit of the Cretaceous System, the Tuscaloosa, is the most important clay-bearing formation in Georgia. He indicated that the age of the formation in Georgia was determined only by its stratigraphic position. Veatch believed that the material making up the Tuscaloosa Formation was derived from disintegrated and decomposed rocks of the Piedmont Plateau. The greater part of the Piedmont region was a land surface for a very long period of geologic time. Streams rapidly carried the weathered residue to the Cretaceous sea. Veatch postulated that an enormous quantity of sediment was dumped rapidly at the stream mouths,
7

forming extensive sand flats. Fine clay particles were deposited in nonpersistent and lenticular beds of white clay in the deeper and quieter waters near the stream mouths. He considered the Tuscaloosa in Georgia a nonmarine deposit.
Smith (1929) concluded that the basal Cretaceous sediments in Georgia were Upper Cretaceous and correlated them with the Middendorf Formation of eastern South Carolina. Smith believed that Veatch's explanation of origin was essentially correct, except that he agreed with Neumann (1927) that the kaolin was deposited in salt water.
Kesler (1963) recognized that in Georgia and South Carolina the kaolin deposits were not limited to the top of the kaolin-bearing sequence of strata. He correctly attributed their tendency to occur in that position to their having been truncated by an unconformity. However, he believed that all of the kaolin-bearing strata were Cretaceous. More recently, pre-Jackson Tertiary strata have been recognized in the kaolin-bearing sequence, separated from the underlying Cretaceous by an unconformity. Thus, two unconformities are present in positions to indicate possible concentrations of kaolin lenses. The lenses of kaolin developed where erosion differentially removed the less-resistant sandy sediments. Kesler's theory of origin included: (1) derivation of the Cretaceous sediments from the crystalline rocks to the northwest by vigorous erosion, and accumulation of coarse feldspathic sands in coalescing deltas; (2) formation of kaolinite by decomposition of the feldspar; and (3) collection of the kaolinite in ponds formed as cut-off segments of distributaries.
Bates (1964) reviewed the various theories of origin of the Georgia kaolins and summarized the mineralogic and geologic data, some of which support a marine origin and some a fresh-water origin. Hinckley (1961) suggested that face-to-face flocculation of kaolin particles in a marine environment would result in the properties that distinguish a so-called "hard" kaolin, whereas edge-to-face flocculation in fresh water would produce a less dense, "soft" clay.
Jonas (1964) concluded from a detailed petrologic study that the originally deposited sediment was muscovite, feldspar, and quartz, and that post-depositional alteration and recrystallization produced the kaolin deposits now mined.
Buie (1964) proposed consideration of the possibility that volcanic ash was the source material for the kaolinite, the ash weathering first to montmorillonite then to kaolinite. The Cretaceous kaolin in central Georgia occurs stratigraphically near the position of volcanic materials reported by Eargle (1955, p. 91) and others, in strata present in western Georgia had farther west in the Coastal Plain. The second author of this guidebook believes that volcanic origin is a concept harmonious with several features of the kaolin that are unexplained by other concepts. However, because of the intense alteration to which the kaolin-bearing sediments have been subjected, and the degree to which crystallization of the kaolinite has occurred, it is not surprising that volcanic glass shards and other specific evidences of volcanic origin have not been found.
The Georgia kaolin deposits have had a complex history and origin, and none of the theories of origin advanced to date are entirely satisfactory. Theories that would require transportation of long, slender, vermicular crystals of kaolinite for long distances, in the form in which they occur in the deposits, do not seem plausible. The purity of the kaolin can be explained by a sedimentary winnowing process, as favored by Kesler (1963) and others, or by in situ alteration of particulate material capable of weathering to kaolinite. The physical environment in which the deposition took place is yet to be established, but it was probably similar to the present coast of Georgia and South Carolina, where abundant offshore sand bars and swampy, muddy lagoons and winding estuaries exist. The low iron content of the kaolin is remarkable but at least two mechanisms are available by which the iron may have been removed. The iron in the kaolin deposits that are still far enough below the surface to have escaped weathering, is mainly in the sulfide form, and upon weatheringif oxidation does not take place too rapidly-the iron can be taken into solution and removed as the sulfate. Removal of iron can also be accomplished by the chelating effect of organic acids from decaying plant materials. Some of the differences in physical properties of the kaolin may be due to the fact that some of the kaolin, particularly in the younger deposits, has been reworked. Other differences in physical properties are probably due to varying
8

degrees of diagenetic alteration, and different amounts of leaching while exposed at the surface during present or earlier erosion intervals. These factors may have some relation to the coarser particle size and the more abundant and larger vermicular crystal growths observed in the kaolin deposits of Cretaceous age. Another puzzling feature, which an adequate theory of origin should explain, is the presence of minute particles of anatase in the kaolin, and especially its prevalence in the deposits of Tertiary age.

EXPLORATION AND EVALUATION OF DEPOSITS
Geologically favorable areas are selected, taking into account topography, elevation, and information on geologic maps and aerial photographs, and exploration drill-hole patterns are laid out. Exploration holes are drilled to depths of as much as 200 feet (61 m) and on 400- to 800-foot (120 to 245m) centers. Auger or fishtail drills are used to penetrate to the top of the kaolin, and then a special core barrel is used to sample the clay. Cores are cleaned and cut into sections of 2 feet (0.6 m) or less long. Each cut sample is then dried, pulverized, and evaluated for several or all of the following: (1) percent grit or screen residue, (2) particle-size distribution, (3) low-shear viscosity, (4) high-shear viscosity, (5) brightness, and (6) leachability.

PREPARATION OF KAOLIN FOR MARKET MINING

Kaolin is mined by sophisticated mechanized methods (Patterson and Murray, in press).

Mining includes the clearing of timber, removal of overburden by scrapers (pans) or large

draglines, mining by either truck haulage or blunging and pumping through pipelines to

beneficiation plants. Land-reclamation plans and schedules must be approved in advance

by State officials, and environmental controls on water contamination and dust emanation

must be complied with. After overburden is removed, most companies do additional

drilling and testing for detailed evaluation of deposits and quality control. One company

hauling by truck uses a unique method of testing and separation of the raw clay according

to product. A kaolin sample is taken from ~ach loaded truck near the mine and tested

while the truck is en route to the plant. The results are available at the plant when the truck

arrives, and the driver is instructed to dump in the appropriate raw-clay hopper.

Kaolin companies have modified mining methods in different ways to comply with

laws governing reclamation. The Freeport Kaolin Co. uses what is called the roll-over

method. This technique involves clearing and partial leveling of the ground with scrapers.

The overburden is removed from the first cut. The kaolin from this cut is removed and

stockpiled with a large dragline. When this cut is completed, the dragline then removes the

overburden from the adjacent cut and dumps it in the mined area. This backfilled area is

then smoothed with bulldozers, and uncovered kaolin is dug and stockpiled on the smoothed

area by the same dragline. Another company does all its stripping with rubber-tired self-

powered scrapers. Such equipment is capable of dumping the overburden in rounded piles

requiring little further grading for reclamation. Other companies using large draglines leave

high ragged spoil piles that are lowered and smoothed to acceptable slopes with bulldozers

and planted with grass or trees.

,

BENEFICIATION
Kaolin is prepared for market by dry and wet processes. The dry process, which involves air floating to remove grit, is simple and yields a lower cost and lower quality product than the wet process. Dry-processed kaolin has properties similar to those of the crude form; therefore, clay processed this way is selected with considerable care. Preferred deposits have desired brightness, low grit content, and particle size with minimal additional processing. The clay is crushed or shredded, dried, pulverized, and air floated.
9

PLANT

WET CYCLONE

Y~L~TNE~ - . .J~L. . -C_E_N_T_l _W=UG=E=~ - ,.1.'- - -, . .- -

'__y:: -------------,,rl:,---- COATING GRADES ----- FILLER GRADES

DELAMINATION TANK

l ~f.l \O'~DEL AM I NATEO GRADES - - - - -

vVACUUM FILTRATE TO WASTE

GAS

BAG PACKER

Figure 3. Flow diagram of kaolin beneficiation. 10

The wet processing of kaolin involves several steps (Fig. 3) and yields highly refined _products. The obvious first step is the dispersing of the clay in water, and this is done in the blunger either in the mine or at the plant. The second step is a degritting process, in which the slurry is passed through classifiers to remove coarser nonclay materials. Some of the coarser kaolin particles are also lost in this step. The following steps vary somewhat in different plants, but they involve washing, purification, separation of particle sizes, and grading to fulfill the specifications of special uses or products. In one of the early steps, the kaolin is acidified with sulfuric acid to a pH of about 3 to dissolve the iron impurities. A strong reducing agent, such as a hydrosulfite, is then added, which reacts with the iron to form a soluble sulfate which is removable during dewatering. Dewatering of the flocculated slurry is done with centrifuges, rotary vacuum filters, or filter presses. The dewatered kaolin is dried with rotary, spray, or drum driers. Most of it is then ground with Raymond or other type of pulverizing mill. Some of the kaolin is shipped in slurry form as 70 percent solids in tank cars.
Most plants produce special delaminated grades of kaolin that are particularly suitable for lightweight paper coatings, paint films, and special rubber applications. The delaminated kaolin is produced by splitting apart the larger books or vermicular crystal growths of kaolinite. The resulting individual platelets are thinner and whiter than the larger aggregates. The splitting is done by wet attrition grinding and extrusion processes.
The most recent advancement in kaolin processing has been the introduction of the high-intensity (18 to 22 kilogauss) magnetic separator, which removes substantial quantities of discolorants that do not respond to convential methods of chemical leaching. The discolorants in Georgia kaolin are primarily iron-stained, titaniferous, and micaceous minerals (Oder and Price, 1973, p. 75). The principal feature of the separator system is a canister filled with a special type of steel wool, in a magnetic field, through which the kaolin slurry is pumped. The magnetic particles remain in the steel wool until the magnet is deenergized and removed by back flushing with a l~ge volume of water under pressure.
Some kaolin is calcined for special products. When heated to 1050 C, it converts to mullite, silica alumina spinel, and cristobalite. The calcined form is whiter, brighter, has better hiding properties when used in thin filler applications, and is more abrasive.
KAOLIN USES AND PRODUCTION
Kaolin has many industrial applications, and new uses are still being discovered. It is a unique industrial mineral because it is chemically inert over a relatively wide pH range, is white, has good covering or hiding power when used as a pigment or extender in coated films and filling applications, is soft and nonabrasive, has low conductivity of heat and electricity, and costs less than most materials with which it competes. Some uses of kaolin require very rigid specifications including particle-size distribution, color and brightness, and viscosity, whereas other uses require practically no specifications, for example, in cement, where the chemical composition is most important. The better grades of kaolin make up most of the tonnage sold and have the highest unit value. Many grades of kaolin are specially designed for specific uses, in particular for paper, paint, rubber, plastics, (Brooks and Morris, 1973), and ceramics.
Approximately 50 percent of the total kaolin produced in the United States is used in paper products (Fig. 4). Kaolin fills interstices of the sheet and coats the surfaces imparting smoothness, gloss, brightness, opacity, and printability. Color-picture magazines commonly contain as much as 30 percent kaolin. The rubber industry uses significant quantities of kaolin as filler or extender in both natural and synthetic rubber. The so-called "hard kaolins" improve such properties as strength, abrasion resistance, and rigidity of rubber used in footwear and cable covers. The "soft" kaolins are used to improve abrasion resistance and lower elasticity of floor tile and soft rubber goods. Historically, kaolin was first used in ceramics, and part of the kaolin produced is sold for making pottery, stoneware, ceramic tile, and other ceramic products. Appreciable tonnages of kaolin are also produced for use in making firebrick and other refractory products. There are more than 25 other uses for kaolin,
11

5000 r-----------------------------------------------------------------------~

I

Other uses Refractories Pottery, stoneware, tile Rubber Paper filling and coating

ez n ~ ~
0
eI n
LL
0
en
z 0 ;Jj
:J 0 I I-
1500
1000
500
1930

1940

1950

1960

1970

Figure 4. Kaolin sold or used by producers, 1929-1971. 12

including the manufacture of chemicals, catalysts, cement, medicines, adhesives, cosmetics, detergents, fertilizers, sizing compounds, linoleum, textiles., etc.
The total kaolin produced in the United States in 1960 was more than three times that of 1940, and the 1973 production was nearly double the 1960 production (Fig. 4) According to preliminary statistical data of the U. S. Bureau of Mines, 5.8 million tons of kaolin was produced in the United States in 1973. Georgia produced more than 4.3 million tons of kaolin in 1973, and the value was more than $137 million (J.D. Cooper, oral commun., 1974). Production and value figures for the individual kaolin districts in Georgia are not available, but probably the Irwinton district produced approximately two-thirds of the total for Georgia in 1973.
13

FIELD TRIP- KAOLIN IN THE MACON-GORDON AREA, NOVEMBER 15,1974 1

The bus will leave Ramada Inn, 2400 Riverside Drive, Macon, Georgia, 8:00a.m., and return to this motel for the overnight stop. Road log for the morning trip. (Distance in miles).

Mileage Interval Cumulative
0.0

0.3

0.3

2.5

2.8

1.3

4.1

5.6

9.7

3.4

13.1

0.2

13.3

0.4

13.7

0.3

14.0

3.6

17.6

Board bus at Ramada Inn; bus will travel northwest to Pierce Avenue entrance on Interstate Highway I-75, and go south on I-75 and I-16.
Turn right on ramp to I-75, continue to fork and proceed left on I-16.
Leave I-16 on right lane ramp at Spring Street exit and turn left on Georgia 49.
Turn right, staying on Georgia 49.
(Pause) Flakey clay rubble exposed in road cut is Twiggs Clay. The clay contains carbonate beds similar to marine fossiliferous beds of Jackson (late Eocene) age. Note that the vegetation planted for erosion control thrives on the clay and grows poorly on the sand. Such clays make much better artificial soil than does the sand, because they contain some of the natural mineral requirements of plants, and they retain moisture better. (A better exposure will be seen over the crest of this hill, but at an unsafe place to stop.)
Right tum on road to Martin Marietta Ruby Granite quarry.
Turn left into shop area adjacent to quarry; circle shop.
(Pause) Note contact of Coastal Plain sediments on crystalline rocks. Lowermost sedimentary beds are of probable Cretaceous age. The flat-topped hill on the far side of the quarry is a reclaimed spoil area. Return to Georgia 49.
Continue northeasterly on Georgia 49.
Turn right on Georgia 18 at crossroads. (Pause) Note red clayey sand of probable Jackson age. Most geologists working in the Coastal Plain now recognize that the red color has little relation to stratigraphy or origin. The red color is apparently related to the state of oxidation of the iron, which is in tum controled by weathering. The Jackson and Claiborne beds are difficult to distinguish where strongly weathered.

1 This road log including Figures 5 and 6 was prepared by B. F. Buie, and it was not submitted to the U. S. Geological Survey for Directors approval for publication.

15

Figure 5. Route and stops of kaolin field trip, Gordon and vicinity . 16

Mileage Interval Cumulative

2.4

20.0

0.3

20.3

3.7

24.0

0.5

24.5

0.7

25.2

1.0

26.2

0.2

26.4

1.2

27.6

(Pause) Note kaolin overlain by sand of Jackson age exposed in road cut on left side of highway. This kaolin has a low grit (+325 mesh) content. It is probably of Cretaceous age.
Twiggs Clay in road cut.
STOP 1 (Fig. 5)
Claiborne age beds are exposed on left side of highway. Road cut exposes prominently cross-bedded sand with abundant kaolin balls and boulders. On the basis of close lithologic similarity, these beds are correlated with Claiborne strata a few miles to the southwest. These beds consist mainly of subrounded quartz grains, ranging in size from medium sand to coarse gravel. Many of the quartz grains are "rotten" and will crumble with slight pressure. Accumulations of dark heavy mineral grains along bedding are common in beds of this type. Some of the large clay boulders are pisolitic; such material in this region generally contains gibbsite. Bauxite boulders of this type elsewhere are as much as 5 feet indiameter. They seem to indicate movement by water in a very high energy environment. Beds having the characteristics of those in this exposure rest unconformably on kaolin of Cretaceous age and they are stratigraphically below minable kaolin deposits.
Gordon city limits.
Road to Freeport Kaolin Company Research Laboratories on left.
Road junction, Georgia 18 and Georgia 18 Spur; turn left to Freeport Kaolin Company.
STOP 2 (Unload bus at parking lot by Freeport Kaolin Co. office.)
Visit plant; hard hats and safety glasses or eye shields will be required. Tour will be conducted by Freeport Kaolin Company personnel. Upon completion of plant tour, reboard bus for drive to Research Laboratory.
Turn right on road to Research Laboratory of Freeport Kaolin Co.
STOP 3 (Unload bus in parking lot at Research Laboratory.)
Conducted to'll' by research personnel of Freeport Kaolin Company. The tour of the Research Laboratory will be followed by LUNCH at the nearby lake. Lunch is scheduled early, to take advantage of the attractive facilities here. (Box lunches provided.)

17

Road log for the afternoon trip
Route extends from Gordon southwesterly through mining areas of Freeport Kaolin Company and Georgia Kaolin Company, to Dry Branch, Ga. and on the J. M. Huber Corporation mines.

Mileage Interval Cumulative
0.0

0.2

0.2

1.0

1.2

0.4

1.6

2.3

3.9

0.6

4.5

0.7

5.2

0.1

5.3

0.3

5.6

Road junction, Georgia 18 & Georgia 18 Spur. Proceed south on Georgia 18.
Unimproved road to General Refractories Company's Cherokee China Clay mine. This mine, now inactive, is at the end of a winding road, about 0.4 mile to the west. The kaolin here contains abundant fossil forms resembling filled tubular borings; it is Tertiary in age.
Crossroad; Georgia 18 and Georgia 57. Continue on Georgia 18.
Turn right on black-top county road (Dry Branch Road). (Pause) Note how the deep red color, in roadcut on right, tends to obscure the lithologic features.
Turn left on graded county road. (Good weather only).
Note reclaimed grassy area on left, and old mine workings on right.
Turn left from county road onto road to Freeport Kaolin Company's degritting plant area.
Haul road turns left to kaolin mine (Good weather only). STOP4 Kaolin mine of Freeport Kaolin Company. The roll-over method of mining is used here; it will be explained by Freeport personnel.
STOP5 Freeport Kaolin Company's degritting plant. The following information has been kindly supplied by Freeport Kaolin Company:
The degritting plant consists of eight 150 GPM capacity primary drag type classifiers and two secondary drag classifiers of the same size.
The slurry pumped by the blungers is received by a DorrOliver DSM screen 6 feet wide by 5.0 mm bar spacing screen located on top of a 30,000-gallon surge tank.
The undersized material is received by the tank and fed, by gravity, to two 1,000-gallon distribution tanks below. Each of the distribution tanks feeds, by gravity, a set of four primary drag classifiers. The oversized material which consists of sand,

18

Mileage Interval Cumulative

0.5

6.1

1.2

7.3

0.8

8.1

0.3

8.4

1.0

9'.4

2.0

11.4

2.3

13.7

~.4

16.1

2.8

18.9

mica and unblunged clay, is removed by each set of four drag classifiers, and is fed by gravity to a 3-inch Denver sand pump, which in turn pumps it to the secondary blunger. This is blunged together with the coarse material removed by the Dorr-Oliver DSM type screen on the surge tank.
The secondary blunger feeds by gravity the set of two secondary drag classifiers. The slurry produced by the primary and secondary drag classifiers is overflowed and by gravity is directed to a bank of eight 100-mesh Sweco vibrating screens where finer sand and mica are removed. The undersized material, containing from 30% to 35% solids is stored in four 250,000-gallon capacity tanks.
The oversized material collected from the Sweco vibrating screens and the waste material from the secondary drag classifiers are transported by gravity to waste impound ponds.
From the degritting plant, return to the county road.
Turn left and go south on graded county road, to place where dragline is operating, which will be Stop 6. STOP 6 (Alternate stop to be made only if mining operations at Stop 4 are temporarily inaccessible.) Strip mining and simultaneous land reclamation. Continue south on graded county road.
Intersection of Myricks Mill Road and Asbury Church Road at Martin's store. Turn right on hard surfaced county road.
(Pause) Note slash pine trees on right, planted in strip mine reclamation project. Mining was by roll-over method. The trees are 8 to 9 years old.
(Pause) Note improved variety of slash pine planted in similar project. These trees are 5 to 6 years old.
Junction with Dry Branch Road at Crosby (or Cannon) Comer; turn left and go southwest through extensive area of mined-out land.
Georgia Kaolin Company's degritting plant on left.
Georgia Kaolin Company's Dry Branch plant is one-half mile to south.
Junction with U.S. Highway 80 at Dry Branch, Ga. Turn left.
Tum right on Stone Creek Church Road. (Pause) This locality is called Pikes Peak. The type section of the Twiggs Clay, of Jackson (upper Eocene) age is a railroad cut

19

Possible stops depending on accessibility
Figure 6. Route and stops of kaolin field trip, J. M. Huber Corp. mining area.
20

Mileage Interval Cumulative

about 0.5 mile east of the road junction. Fuller's earth was formerly mined a short distance to the north. The most recent product was absorbent granules produced by the General Reduction Company. The plant, which was in Macon, has recently been sold and dismantled.
The Twiggs Clay here consists mainly of montmorillonite and a poorly ordered form of silica of the type that has been called opal or opal-cristobalite. X-ray diffraction traces of opal of this type commonly contain broad diffuse reflections of cristobalite.

0.4

19.3

Turn left on unimproved county road (Good weather only). This is at the northern edge of the J. M. Huber Corporation mining area, in which several observations of interest can be made. These include:
Field comparison of the Cretaceous age kaolin with kaolin of Tertiary age;
Distinguishing characteristics of the kaolin-bearing sequence of Tertiary strata;
Distinction between the pre-Jackson Tertiary strata, which at some places contain commercial deposits of kaolin, and the Jackson strata, in which commercial deposits of kaolin are unknown in this area;
The significance of unconformities in relation to the occurrence of kaolin lenses;
The increasing significance of artesian groundwater, as kaolin mining is extended farther down-dip;
Some experimental methods in reclamation of mined lands.

Note: On the accompanying map, Figure 6, several places are indicated where the observation mentioned can be made. On the basis of conditions existing nearer the date of the field trip, the places most appropriate for visiting will be selected. B.F.B.

21

PART II - FULLER'S EARTH OF THE MEIGS-ATTAPULGUS-QUINCY DISTRICT, GEORGIA AND FLORIDA
INTRODUCTION
Fuller's earth deposits occur in a belt in southern Georgia and northern Florida (Fig. 7) extending from near Meigs, through the vicinity of Attapulgus, Ga., to the region south of Quincy, Fla., a distance of approximately 50 miles (80 km). This district historically has lead the nation in fuller's earth production. At present, seven plants are active, and several others were active in the past.
GEOLOGY STRATIGRAPHY
Nearly all the rocks exposed in the Meigs-Attapulgus-Quincy district are of Miocene age or younger. However, limestone of Oligocene age is below only a shallow blanket of residuum at places on the Dougherty Plain along the western margin of the district, and limestone float containing Oligocene Foraminifera was found in the eastern part of the district. The following discussions will be concerned primarily with the Hawthorn Formation, which contains the fuller's earth, and beds immediately overlying this unit. However, the other sedimentary rocks in the district are described briefly in the generalized section (Fig. 8).
HAWTHORN FORMATION
Name. -The name Hawthorn Formation has been used throughout northern Florida and most of the Coastal Plain region of Georgia and Alabama for problematical beds in several different ways. Most of the problems related to this formation result from its variable characteristics, its gradational relationship with the formations above and below it, and poor and weathered exposures, which make it impossible to observe all of the formation at one place. Because of these characteristics, the Hawthorn Formation, as noted by Puri and Vernon (1964, p. 145) " ... perhaps is the most misunderstood formational unit in southeastern United States. It has been the dumping ground for alluvial, terrestrial, marine, deltaic, and pro-deltaic beds of diverse lithologic units in Florida and Georgia, that are stratigraphic equivalents of the Alum Bluff Stage."
In this report the name Hawthorn Formation is applied to rocks that are primarily of marine origin that overlie the Tampa Limestone. The rocks above the Hawthorn Formation throughout most of the Meigs-Attapulgus-Quincy district are assigned to the Miccosukee Formation as used by Hendry and Yon (1967) but in the southernmost part of the district the thin Jackson Bluff Formation as used by Hendry and Sproul (1966, p. 75) is present between the Hawthorn and Miccosukee Formations.
Distribution.-The Hawthorn Formation extends throughout the Meigs-AttapulgusQuincy district, except in a belt along the western boundary of the district and in scattered solution depressions in the eastern part, where it has been eroded. The formation is blanketed by younger formations in all upland areas. Virtually all major stream valleys in the central part of the district cut into but not through the Hawthorn Formation. However, most valley walls formed by this formation are covered by slope wash, slumped material, and vegetation, and natural exposures are rare.
Lithology. -All of the valuable fuller's earth deposits in the Meigs-Attapulgus-Quincy district are in the Hawthorn Formation, but this formation consists chiefly of fine- to medium-grained quartz sand, containing much silt and clay, minor carbonate beds, and traces
23

G uL F
0 F
M EXI c0

v
.....
[..,
~
~ ~
E-.
~

..,., .

~

\

0

50

100

150

200 MILES

\

I

0

50

100

150 200 KILOMETERS

Figure 7. Location of Meigs-Attapulgus-Quincy district, Georgia and Florida. 24

SERIES
Holocene and Pleistocene

FORMATION

Miccosukee Formation as used by Hendry
and Yon (1967)

THICKNESS (FEET)

DESCRIPTION

0-60

Alluvial and eolian deposits of sand, silt, and muck

0-80

Reddish-brown, brown, and yellowish-brown clay, medium to coarse sand, and thin kaolinitic clay beds; crossbedded ; contains channel-fill deposits and lenticular units of quartz gravel; marine fossils absent but con -
tains Callianassa borings locally

Jackson Bluff Formation as used by Hendry
and Sproul ( 1966)
Miocene
Hawthorn Formation

0-20

Greenish-gray and brown sandy clays and clayey sands; contains abundant marine fossils

100-275

Fine to medium quartz sand and clayey silt; contains fuller's earth and other clays and scattered very sandy limestone beds; locally contains minor pelletal and secondary phosphate, opal concretions, and irregular masses of opal

Tampa Limestone

....
. ' .. .
o o

-";=.
I o o o ' ~ ,.

. ...

.. :..:... . , .. .. .. 0 0

. . . . o o 0,.. 1 O
0

~ 0

0

O 0 ol 0 : 0

0

I 0

0

I

0

: :' .: ... .. . .

' o I ' ,'

25-250

Light-gray and light-grayish-brown very sandy limestone, quartz sand , and thin clay beds; locally contains minor dolomitic sandy limestone and, in places, massive white limestone occurs in lower part; Foraminifera rare

Oligocene

II I I I I

Suwannee Limestone

I I I

I . . i :.:..

'.

I I

0 ' -
I
I I

- ._::.
I I
I I

I

L

......

I

. :.:;

I

II I I I

II I I J

24-230

Light-yellow to light-brown crystalline limestone containing much dolomitic limestone and scattered beds of dolomite; white crystalline limestone occurs in upper part locally; minor quantities of white quartz sand is present in some beds, and opal and chert masses are common; Foraminifera locally abundant

Figure 8. Generalized section of the rocks exposed in the Meigs-Attapulgus-Quincy district.

25

of phosphatic material. The sand is mostly rounded and subrounded quartz, and most of it is intermixed with clay and silt. Most of the clay other than that in the fuller's earth deposits consists of mixtures of palygorskite and montmorillonite, but much of the clay in weathered parts of the formation is kaolinitic, and kaolinite is virtually the only clay mineral present in thoroughly weathered parts. The carbonate beds consist chiefly of very sandy limestone, and some are dolomitic. Most of the carbonate beds are no more than 5 feet (1.5 m) thick and are interbedded with sand, some of which is sufficiently cemented with calcite to be properly called sandstone. Carbonate beds are much more abundant in the central part of the Gulf trough in the central part of the district, where the Hawthorn Formation is much thicker than on either side. Carbonate beds occur above the fuller's earth in the area south of Attapulgus, Ga., but none are present above the clay in the northern part of the district. Studies of drill core and water-well samples reveal that carbonate beds are abundant at depth in the central part of the Gulf trough, and at places so much sandy limestone is present that the Hawthorn Formation grades downward into the Tampa Limestone, which is also sandy. Most of the phosphate in the Hawthorn Formation is in scattered pelletal grains and fish teeth and bones consisting of carbonate-fluorapatite. Most of the phosphate pellets at depth are black and shiny, and those in the shallower more weathered parts are brown, tan, or light gray.
Opal occurs in the Hawthorn Formation at several localities. Masses as much as 3 feet (1 m) thick of light-yellowish-gray brecciated flintlike brittle opal, which weathers white, occur 1.7 miles (2 km) south of Cairo, Ga. This opal, which can be distinguished from chert by X-ray methods, is chiefly hydrous silica, but it also contains minor quantities of palygorskite and other clay minerals as well as some detrital quartz. Clayey opal concretions are common in parts of the fuller's earth in the northern part of the district.
Fossils are rare in the Hawthorn Formation throughout most of its extent. However, some of the carbonate beds exposed in fuller's earth mines in the southern part of the district are almost coquina, and these beds also contain Foraminifera and ostracod faunas. Microfossils are common in fuller's earth in the northern part of the district. Both vertebrate fossils and petrified tree trunks have been recovered from that part of the formation removed in stripping in fuller's earth near Quincy and Midway, Fla.
Stratigraphic relations.-North of the Meigs-Attapulgus-Quincy district the Hawthorn Formation apparently overlies several older formations unconformably. This formation also rests unconformably on the Tampa Limestone in the eastern part of Leon County, Fla., as indicated by differences in lithology between the two formations (Hendry and Sproul, 1966, p. 67). In the Gulf trough in the central part of the district, however, the Hawthorn Formation as observed in well cuttings grades gradually downward into the Tampa Limestone through a thick zone in which unfossiliferous sandy limestone layers increase in abundance downward. Where the gradation is present only an arbitrary interpretation of the position of the contact between the two formations is possible, and there is no justification for assuming an unconformity is present.
The contact by the Hawthorn with the overlying Miccosukee Formation as used by Hendry and Yon (1967) is also problematical in many places. The principal criterion used in picking this contact is the upper limit of beds having definite marine characteristics. At places, the recognition of the top of marine beds was based on marine micro- or macrofossils, and at other it was the presence of limestone, pelletal phosphate, or palygorskite fuller's earth.
Additional characteristics used in separating the two formations were the appreciably larger grain size of the sand in the Miccosukee Formation than in the Hawthorn Formation at most places and the more abundant white kaolin layers in the Miccosukee Formation than in the underlying Hawthorn Formation. Also, an unconformity marked by a coarse sand gravel and cobbles in channel-fill deposits in the lower part of the Miccosukee Formation occurs at several localities. At other places the top of the Hawthorn is marked by a weathered kaolinitic zone.
Though the criteria outlined for distinguishing the Hawthorn and Miccosukee Formations seem reliable, the two formations are extremely difficult to distinguish where weathering has progressed to considerable depths. The grain size of the two formations varies considerably,
26

and in places none of the other characteristics for identifying the formations are present. Locally, some of the thin limestones have been removed by leaching, and secondary phosphate minerals found at several localities suggest that all of the pelletal phosphate may have been leached from some beds.
Thickness. -over most of the district the Hawthorn Formation is no more than 100 feet (30.5 m) thick, but in the central part of the Gulf trough some wells have penetrated beds more than 275 feet (83.9 m) thick that could be considered part of this formatian. However, wherever this formation is exceptionally thick, its lower part contains much sandy limestone. How much of this sandy limestone should be assigned to the Hawthorn Formation and how much to the Tampa Limestone is largely a matter of opinion.
MICCOSUKEE FORMATION AS USED BY HENDRY AND YON (1967)
Throughout most of the district, the Hawthorn Formation is overlain by a problematical clastic formation, which has been called the Miccosukee Formation (Hendry and Yon, 1967) in recent years. One of the major problems related to the Miccosukee Formation is concerned with its age, and much of the uncertainty is due to the absence of fossils in the unit. No fossils were found in this formation in the Meigs-Attapulgus-Quincy district, and the only ones it is known to contain in the region are animal teeth of late Miocene age discovered (Yon, 1965) east of the district. These fossils and the position of this formation above the Miocene Hawthorn Formation make it reasonably certain that the Miccosukee is younger than middle Miocene. The upper part of the formation, however, may contain some beds of Pliocene age, and, if not, the only possible sedimentary record of the Pliocene Epoch preserved in the district is in the sand deposits, considered to be of Pleistocene age in this report, or in one of the lower soil horizons.
A second problem is the identification of both the upper and lower contacts of the Miccosukee Formation and even the entire formation at many places where it is thin and thoroughly weathered. The Miccosukee Formation overlies the Hawthorn Formation unconformably, as it overlaps the older Tampa Limestone in Jefferson County, Fla. and the younger Jackson Bluff Formation as used by Hendry and Sproul (1966, p. 84) in Leon County, Fla. However, the unconformity is difficult to recognize in much of the Meigs-Attapulgus-Quincy district, because the lithology of the upper part of the Hawthorn Formation is very similar to that of the Miccosukee Formation.
The maximum thickness of the Miccosukee Formation in the Meigs-Attapulgus-Quincy district is approximately 80 feet (24.4 m). However, the formation is much thinner than this at most places, and it has been eroded completely in the areas occupied by the larger stream valleys. The maximum thickness measured was in Florida, and the formation is generally much thicker in Florida than it is in the northern part of the district. In the vicinity of the fuller's earth pits near Meigs and Ochlocknee, the formation is only 15 to 25 feet (4.6 to 7.6 m) thick.
Hendry and Yon (1967, p. 252) described the Miccosukee Formation in Jefferson and Leon Counties, Fla., as consisting of continental deposits, presumably because of the vertebrate fossils, lithologic character, and abundant crossbedding. However, burrows of Callianassa, which are indicative of littoral and shallow neritic environments, were found in the upper part of the formation at one locality in the Meigs-Attapulgus-Quincy district, indicating that at least part of the formation in this area was deposited under nearshore marine conditions. The burrows of Callianassa are similln to those in the older geologic reports referred to as Halymenites and as Ophiomorpha nodo1>.1 var. spatha in some recent papers.
The Miccosukee Formation consists of lenticular clayey sands, clay beds, and local channel-fill deposits of gravel. The upper part is chiefly cut-and-fill deposits and is, in general, coarser grained than the lower part. Crossbedding is co._-~:wn throughout the formation. The clay beds range from paper-thin laminae to beds mu~~ t-.,.n 5 feet (1.5 m) thick. The fresh deeply buried clay is greenish gray and is chiefly mo11tmorillonite. The clay in the upper thoroughly weathered part is ordinarily white and is chiefly kaolinite. Some of the kaolinite associated with gravel and coarse sand occurs as water-rounded clay balls.
27

STRUCTURE
REGIONAL STRUCTURE OF THE COASTAL PLAIN
The Meigs-Attapulgus-Quincy district is within the extensive belt of gently dipping sedimentary rocks underlying the Coastal Plain. In most of the Georgia part of the Coastal Plain, the strike of these layered rocks is in a northeast-southwest direction, and the dip is toward the Atlantic Ocean. The strike shifts to a more westerly direction approximately along the Chattahoochee River, which forms the boundary between Georgia and Alabama west of the Meigs-Attapulgus-Quincy district. Along the river and farther west, the dip is to the south and, therefore, toward the Gulf of Mexico. In most places the dip is so gentle it cannot be observed in outcrops, and it can rarely be measured by field methods. One of the places where the dip can be measured is along the Chattahoochee River, where Toulmin and LaMoreaux (1963, p. 385) measured many sections, and using the river level as a datum, found that beds of early Tertiary age dip 13 feet per mile (2.4 m per km).

GULF TROUGH, A STRUCTURAL FEATURE(?)
An elongate belt in which sedimentary rocks of Miocene age are much thicker than on either side (Fig. 9) extends in a northeast-southwest direction across the Meigs-Attapulgus-
EXPLANATION 0223
Well Thickness of Miocene to Holocene
sediments, in feet
- - - - 7 0 0- -- Isopach
Miocene to Holocene sediments, in feet

FLORIDA

Axis of Gulf trough

85

84

83 '

0

10 20 30

40 50 MILES

I I I I II I I I

I

I

0 10 20 30 40 50 KILOMETERS

Figure 9. Thickness of Miocene to Holocene sediments in Gulf Trough in southwestern Georgia, modified from Herrick and Vorhis (1963, Fig. 2).

Quincy district. The Florida part of this belt is in the northern part of a geologic feature that was recognized as an embayment of the Gulf of Mexico, which Johnson (1892) named the Chattahoochee embayment. This feature is now called the Apalachicola embayment (Pressler, 1947, p. 1853; Puri and Vernon, 1964, p. 1, fig. 2; Hendry and Sproul, 1966, p. 95). This same embayment has been called the Southwest Georgia basin by several authors, but embayment is preferred over basin because the feature is not closed on its southern end, and Apalachicola would seem to be a more appropriate name than Southwest Georgia because much of this feature is in Florida. The Apalachicola embayment has been illustrated by several authors as a large triangular feature having one side along the Gulf of Mexico in the vicinity of the delta of the Apalachicola River and the apex in southwestern Georgia. The elongate belt of thick Miocene rocks extends much farther northeast than the area most authors have considered the Apalachicola embayment to occupy. All of the

28

elongate belt in Georgia, including the northern part of the Apalachicola embayment, has been named the "Gulf Trough of Georgia" by Herrick and Vorhis (1963, p. 55, figs. 2 and 3); Hendry and Sproul (1966, p. 97) dropped the Georgia restriction to the name and used simply the "Gulf trough." The term Gulf trough is used in this report for the entire belt of thick Miocene rocks in the district, and it includes the northern part of the Apalachicola embayment as located by several authors.
The Gulf trough has been referred to as a syncline and a graben, but in the senior author's opinion, the Gulf trough was most likely a strait separating peninsular Florida from the mainland during Oligocene and much of Miocene time. The principal reason for this opinion is that isopachous maps of Oligocene and Miocene rocks in the trough (Toulmin, 1952, fig. 7; Herrick and Vorhis, 1963, Figs. 2 and 3) show an outline similar to that of the present Straits of Florida (Uchupi, 1966) which separates Florida from the Great Bahama Banks. The idea of peninsular Florida being separated from the mainland in the past is not new, as Dall (Dall and Harris, 1892, p. 111, 121-122) proposed the "Suwannee Strait" for a belt of thick Miocene sediments much farther east than the Gulf trough. Rainwater (1956, p. 1727) suggested that the Suwannee Strait extended along the Georgia-Florida boundary as far west as Jackson County, Fla., which is west of the Meigs-Attapulgus-Quincy district. He, therefore, deserves credit for the idea of a strait in this region, but he believed that the strait extended much more to the east than the isopachous maps show the Gulf trough to extend.
FULLER'S EARTH DEPOSITS
DEFINITION
The term "fuller's earth" comes from the ancient use of fine-grained earthy materials and water in cleaning or fulling wool, thereby removing oil and dirt. The term has no compositional or mineralogical significance, and several types of clay and other fine-grained materials have been used in fulling. The usage of the term was modified in the latter part of the last century to include earths of value, without chemical treatment, in decolorizing and purifying mineral, vegetable, and animal oils.
Though the fuller's earth of the Meigs-Attapulgus-Quincy district was first used in purifying oils, the tonnage now produced for this purpose is surpassed many times by that sold for other uses. Nevertheless, the term "fuller's earth" is retained for these clays, because of the lack of a more suitable term and the production of this and similar clay is reported by the U.S. Bureau of Mines as fuller's earth. Perhaps some justification for the application of the term "fuller's earth" to so many products lies in the fact that most of them have adsorbent properties.
MINERALOGY
The fuller's earth deposits of the Meigs-Attapulgus-Quincy district are of variable mineral composition. A few of the pure deposits consist chiefly of one clay mineral and contain only minor amounts of other clay and nonclay minerals. Most deposits, however, are mixtures of clay minerals and contain several detrital, authigenic, and diagenic nonclay minerals. Material of biogenic origin is ~bundant in some deposits.
CLAY MINERALS
Palygorskite and sepiolite.-Palygorskite (attapulgite) and sepiolite are complex magne;;um silicate minerals having a fibrous crystal habit (Fig. 10). ThesP ...:nerals commonly occur iu close association and are so similar that some mineralogists believe intergrowths of even more complex structural variation may exist.
29

Figure 10. Palygorskite (attapulgite) fuller's earth. Photograph by E. J. Dwornik. 30

(

O

H

Acco h Mg5

rding Sis 0

to 2 0

Bradley (1940, p. 40 4H20, but substituti

6 o

), n

pa of

lygorski Al3+ for

te has eithe

an ideal r Mg* or

fSoir4m+ tualkaeos fp(lOacHe.2

)4 It

consists of silica chains linked in amphibolelike structures and has both monoclinic and

orthorhombic symmetry. Sepiolite, (Si 1 2 )(Mg9 )0 3 0 (OH) 6 (OH2 )4 6H2 0, is similar to palygorskite, but it is thought to have extra silica tetrahedrons on the amphibole chain at

regular intervals (Grim, 1968, p. 116), so that the unit cell is somewhat larger than for

palygorskite. Further information on these minerals and how they were identified can be

found in Patterson (in press) and Weaver and Beck (1972).

Palygorskite is most abundant in the Attapulgus-Quincy part of the district where it

comprises 70 to 80 percent of some fuller's earth deposits. It rarely makes up more than

20 percent of the fuller's earth mined in the vicinities of Meigs and Ochlocknee, but it was

found to be abundant in a few localities in the central part of the district where no mining

has been done recently. Sepiolite is rare, if not absent, in the southern part of the district,

but it forms as much as 10 percent of deposits in the northern part. Scattered deposits

containing minor quantities of sepiolite were also penetrated in augering in the central part

of the district.

Montmorillonite.-Montmorillonite is a clay mineral consisting of two silica tetrahedral

sheets having a central alumina octahedral sheet. The theoretical formula of this mineral,

following calculations of Ross and Hendricks (1945, p. 23), is generally considered to be

(OH)4 Sis (Al3.34Mgo.66 )02o .
.j,
Nao.66
The arrow indicates the group has a deficiency of charge which requires an additional exchangeable ion external to the silica sheet. Here this charge is shown as balanced by Na. The exchangeable ion on montmorillonite in the Meigs-Attapulgus-Quincy district is probably ca++ instead of Na+, and W may be the balancing ion in some of the weathered parts of deposits.
Kaolinite.-Kaolinite, (OH) 8 Si4 Al40 10 , occurs in the upper weathered part of many deposits. Small quantities of this mineral were found in the upper parts of deposits mined in the northern part of the district. It also is common in the upper part of deposits in the central part of the district and was found in samples from several outcrops.

DETRITAL NONCLAY MINERALS

Quartz is the most abundant detrital mineral in the fuller's earth. It ranges in abundance from trace amounts to so much that the fuller's earth might properly be called a clayey sand, and very sandy deposits have no value. Most quartz occurs in rounded to subrounded, frosted grains, but angular clear grains occur in some deposits. Grain size of most of the quartz ranges from silt to medium sand, and very little of it is in clay-sized particles. Feldspar is the second most common detrital mineral in the fuller's earth. It was found to make up as much as 20 percent of some of the impure deposits in the central part of the district, but it is rare or absent in most deposits mined. Several heavy minerals, typical of sedimentary suites in Miocene rocks of the Coastal Plain, including garnet, sillimanite, rutile, and ilmenite are present in more than trace amounts in virtually all deposits.

AUTHIGENIC AND DIAGENIC NONCLAY MATERIALS
Calcite. -Calcite, in addition to that of biogenic origin occurs in concretions, discrete crystals, scattered veinlets, and as desiccation-crack fillings in the fuller's earth. Most concretions are small, but a few are a foot or more across and 6 to 8 inches (15 to 20 em) thick. The individual calcite crystals, which are scattered through some deposits, ordinarily are suffiuently large to be observed in hand specimen, and some are as much as one-fourth inch across. The veinlets are rarely as much as one-half inch thick, and many are paper-thin

31

fillings along joints. The desiccation crack fillings are as much as an inch thick and extend downward from the top of one deposit for 1112 feet (0.5 m). All the forms of calcite are generally rare in most of the deposits mined, but they are so abundant locally that parts of some deposits must be bypassed or discarded in mining. Excessive calcite found in evaluation drilling is also one of the principal reasons many deposits have little value.
The discrete crystals, veinlets, desiccation crack fillings, and some concretions are virtually pure calcite. Some concretions, however, were found to contain appreciable quantities of dolomite mixed with the calcite, and many of the concretions are quite sandy.
Carbonate-fluorapatite. -Trace amounts of carbonate-fluorapatite occur in the fuller's earth deposits, principally as animal remains and in pelletal form. Most of these phosphatic materials are in the sand and silt lenses which are common in some deposits, but scattered phosphatic materials have been found in the fuller's earth.
Dolomite.-White chalky dolomite occurs as thin beds and concretion-like algal heads in the fuller's earth in the central and southern parts of the district. The beds range from 1 to 8 inches (2 to 20 em) in thickness, and the concretions are as much as Ph feet (.5 m) in longest dimension. They were identified by the presence of growth layers in some of them, which were observed after cutting and polishing. Algal heads commonly are bulbous, and many resemble cauliflower heads. Some of the bedded dolomite appears massive and dense in hand specimen but consists of rhombohedral crystals ranging in size from about 1 to 15 m. Most of these grains have isotropic nuclei which are too small to identify (Fig. 11).
Figure 11. Powder mount of dolomite in fuller's earth.
Opal. -Clayey opal concretions, which are ovoid and reach a maximum length of 6 inches (15.4 em), occur in the fuller's earth at a few places in the northern part of the district. They are so abundant in parts of one deposit the fuller's earth is discarded in mining. These opal concretions appear similar to the clay which contains them but are much harder. One of these opal concretions was examined by electron microscopy by Pollard and others (1971). They found that the silica occurs mainly in the form of spheres 0.1-.9 min diameter. Some of these spheres coalesce to form rods, sheets, and blocks. The origin of at least some of the spheres appears to be related to the dissolution of diatoms or other siliceous fossils.
32

Material of biogenic origin.-Trace amounts of calcite grains, which are mainly rounded shell fragments, occur in some deposits in the central part of the district. Fish teeth also have been found in fuller's earth, but they are rare. Diatoms are so abundant in the northern part of the district that some layers could be considered a clayey diatomaceous earth. Diatoms are rare in the southern part, and those that are present are poorly preserved and show evidence of solution, suggesting that they may once have been more abundant in this part of the district too. Silicoflagellates and sponge spicules are common in the fuller's earth in the northern part of the district but are rare in the southern part.
OCCURRENCE
The fuller's earth deposits occur in large lenses that locally form a discontinuous bed in the upper part of the Hawthorn Formation. Though fuller's earth is scattered throughout, the deposits that have been mined most extensively are in the northern and southern parts of the district. Small mines have been operated in the central part in the past, but none have been active in recent years.
The deposits in the northern part of the district are thicker and more continuous than those in the southern part. The fuller's earth beds near Meigs and Ochlocknee, Ga., are as much as 60 feet (20m) thick according to water-well records, and deposits 32 (9.7 m) and 47 feet (14.3 m) thick are mined. Deposits mined in the Attapulgus, Ga.-Quincy, Fla., parts of the district range from 7 (2.1 m) to more than 10 feet (3m) thick. However, lenticular deposits in this part of the district overlap, and at places, two layers of fuller's earth, each nearly 10 feet (3m) thick and separated by sandy beds as much as 11 feet (3.4 m) thick, are mined. In a few places, three overlapping layers are present.
The lithologies of the fuller's earth in the two parts of the district are also quite different. In addition to the significant differences in clay-mineral composition described in following discussions, clay pebble zones are common in the middle and upper parts of deposits near Meigs and Ochlocknee, Ga., but do not occur in the southern part of the district. The clay pebbles occur with quartz sand in layers ranging from 112 to 3 inches (1 to 7 em) in thickness. The pebbles may be as much as 2 inches (5 em) in longest dimension, but most are smaller. Most pebbles consist of the same type of clay that makes up more massive parts of the deposit, but several were found to be richer in attapulgite than the deposits which enclose them.
The position of the fuller's earth in the Hawthorn Formation and the kinds of beds above the deposits are quite different in the northern and southern parts of the district. In the northern part, the fuller's earth occurs either at the top of the Hawthorn Formation or with nly a f w feet of clayey and sandy beds separating the fuller's earth from the overlying Miccosul{ee Formation as used by Hendry and Yon (1967). In the southern part of the distxict, Hawthom beds as much as 70 fe t (21 m) thick are present above the fuller's earth. These b ds consist mainly of clayey sand, mu h of which is carbonate cemented, and carbonate beds and minor quantities of clay.
ORIGIN
A completely satisfactory explanation of the origin of the fuller's earth in the MeigsAttapulgus-Quincy districts has never be~n found, despite the work of the senior author (Patterson, in press) and considerable research and speculation by other geologists and mineralogists on these deposits and similar ones elsewhere. Clearly, the origin of the deposits is related to the origin of the dolomite and phosphate minerals that occur in the fuller's earth, and the formation of these two minerals has also been difficult for geologists to understand. One of the principal difficulties is that the similar clay minerals, palygorskite and sejJiolite, that are present in the deposits are in fine fibrous particles that could not have withstood transportation and therefore must have formed in place. However, the
33

other clay minerals, mainly montmorillonite and kaolinite, that are present in parts of the deposits could have been introduced at the time of deposition, as were quartz sand and other detrital minerals. The explanation is further complicated because some of the characteristics of deposits may have originated either penecontemporaneously, by diagenetic changes long after overlying beds were deposited, or from deep weathering related to the present surface. Another problem is whether or not all deposits throughout the district are the same age. The deposits in the northern part of the district differ considerably from those in the southern part in mineralogy, abundance of diatoms, stratigraphic position with respect to the top of the Hawthorn Formation, and altitude above sea level. These differences suggest that the deposits are younger in the northern part, that they are progressively older to the south, and that minor changes in environments of deposition took place during the formation of deposits in the district. However, all of these different characteristics may have resulted from geologic factors other than age and environment of deposition.
Montmorillonite is the most abundant mineral in some of the fuller's earth deposits. Part of it apparently formed by the weathering of palygorskite (attapulgite) but montmorillonite occurs elsewhere in several different types of rocks, and some of it in these fuller's earth deposits may have been deposited nearly in its present form. The purest and best known montmorillonite occurring elsewhere is in bentonite, a clay formed by the alteration of finegrained minerals and glass in volcanic ash or tuff. Montmorillonite also forms by hydrothermal processes and by weathering of certain types of igneous rocks, particularly in areas of low rainfall or where drainage is restricted.
Kaolinite is abundant in the upper parts of fuller's earth deposits under shallow overburden, particularly in the northern part of the district. The gradation of kaolinite downward into montmorillonite in fuller's earth deposits near the surface suggests that it formed by weathering of this mineral but some of the kaolinite could have been deposited virtually in its present form.
Several theories have been advanced to explain the origin of palygorskite and sepiolite. Longchambon (1935) thought they form by the alteration of amphibole and pyroxene, presumably because these minerals also have elongate chainlike atomic structures. Kerr (1937, p. 549), before the structure of palygorskite was understood, favored the idea that the "Attapulgus clay" was a form of montmorillonite resulting from the weathering of crystalline rocks of the highlands. Millot and his coworkers (Millot and others, 1957) believe in a process of neoformation which is apparently similar to halmyrolysis for the origin of palygorskite and sepiolite. According to this idea, these minerals form in marine or restricted nonmarine environments. The silica is made available by the weathering of rocks in nearby land areas. Magnesium either comes from the same source or is concentrated from seawater. Rateev (1965, p. 179) concluded that conditions favorable for sepiolite formation are high carbon concentration, high pH, and high Si02 activity. He noted that such conditions are most likely to exist in desiccating lakes in arid regions. McClellan (1964, p. 91-96) advanced the idea that palygorskite in Georgia and Florida formed from the silica dissolved from diatoms and magnesium introduced by sulfate spring water. However, only minor movement of ground water has occurred, inasmuch as the carbonate rocks associated with the fuller's earth show little evidence of solution. Moreover, some of the older ones that are cavernous contain no large deposits of fuller's earth.
The idea that the fuller's earth in the Meigs-Attapulgus-Quincy district and similar clay in other places in Southeastern United States formed from volcanic ash was considered by Grim (1933), who studied samples from several localities. Such an origin for fuller's earthtype clays in Levy and Citrus Counties, Fla., was also considered by Vernon (1951, p. 187) who attributed to C. S. Ross the observation that these particular deposits consist chiefly of montmorillonite anci opal and have all the characteristics of bentonite, except no volcanic shards have been found in them. Heron and Johnson (1966, p. 61) reached similar conclusions for Miocene clays in Beaufort County, S.C., as did Espenshade and Spencer (1963, p. 20) for fuller's earth in peninsular Florida. Gremillion (Buie and Gremillion, 1963, p. 25; Gremillion, 1965a, 1965b, p. 89-91) argued strongly in support of the theory that the palygorskite in the Meigs-Attapulgus-Quincy district formed from volcanic ash, but he supplied little supporting evidence for this idea. Hathaway and others (1970, p. 20-22)
34

believe that palygorskite and sepiolite in Miocene rocks on the submarine Blake Plateau east of Florida formed from ash and they cite the presence of a zeolite mineral in these rocks and abundant volcanic ash in Oligocene beds in support of this idea.
The dolomite and filled mud cracks establish that during at least part of their history some fuller's earth deposits were above sea level in an area of a mudflat or shallow lagoon. An intratidal or supratidal origin of the dolomite is indicated by its pronounced similarity to dolomite forming penecontemporaneously in a mudflat or sebkha along the Persian Gulf (Illing and others, 1965), in supratidal areas in the Bahamas (Shinn and others, 1965), and in very restricted supratidal lagoons in southwestern Australia (von der Borch and others, 1964). The dolomite in both the fuller's earth deposits and in the sebkha along the Persian Gulf is very fine grained and occurs in separate rhombs that are unlikely to have formed where any spatial restriction by enclosing lithified sediments was present. The nuclei in many of the dolomite rhombs in the fuller's earth (Fig. 9) also indicate nucleation around preexisting particles without spatial restrictions. Furthermore, the cauliflowerlike dolomite concretions in some fuller's earth resemble bulbous masses caused by algae communities described in the Persian Gulf sebkha by Illing and others (1965, p. 93).
The foregoing explanation for the origin of palygorskite (attapulgite) and dolomite is similar to interpretations by Weaver and Beck (1972, p. 55). After a thorough study of drill core from the vicinity of Attapulgus, Ga., these authors concluded, "The horizontal bedded clay-rich attapulgite beds must have been deposited in a quiet lagoon, probably hypersaline; the dolomite beds were deposited in a similar environment possibly during periods of increased salinity or decreased availability of Si and Al."
The problem of origin of palygorskite and sepiolite, inasmuch as they must have formed in place, is mainly the source of silica, aluminum, and magnesium which together with water are the chief components. Observations cited in the foregoing section indicate that dolomite has formed during or shortly after the evaporation of sea water; therefore, most of the magnesium required for the formation of palygorskite and sepiolite most likely came from the same source. The idea that these minerals can form by halmyrolysis or neoformation from sea water, if sufficient aluminum and silica are present, is supported by the findings of Wollast and others (1968). They were able to synthesize a magnesian sepiolite at room temperature from seawater enriched with sodium metasilicate. Siffert and Wey (1962) also were able to make sepiolite at low temperatures in the laboratory from Si(OH)4 and MgCl 2 Inasmuch as most of the magnesium in palygorskite and sepiolite apparently came from seawater, the remaining problem is mainly concerned with the source of aluminum and silica. The abundant diatoms and silicoflagellate remains in deposits in the northern part of the district indicate that the water in which the fuller's earth accumulated was supplied with abundant silica. As seawater is ordinarily deficient in silica and aluminum, both probably were introduced in the form of silicate minerals and dissolved 'Tiatter carried by streams draining areas of weathered rocks, rather than from volcanic ash. Reasons for these assumptions will be outlined in following paragraphs.
Probably some volcanic ash did accumulate in restricted basins in which palygorskite and sepiolite formed, but little support can be mustered for the idea that ash was the major parent material. Evidence has been found in recent years for the transport of very fine grained minerals for great distances by tropospheric air currents. Considering the volcanic activity in southwestern United States, Mexico, and the Caribbean region during Miocene time and in other parts of the world, it is unlikely that any appreciable thickness of Miocene sedimentary rocks anywhere is completely free of air-transported volcanic matter. However, only the following weak evidence and reasonintt supports the idea that the palygorskite and sepiolite in the Meigs-Attapulgus-Quincy district formed from volcanic ash: (1) Some deposits conf.,;.., trace amounts of angular feldspar. (2) A few grains of embayed quartz of the type considered to be indicative of volcanic origin by Krynine (1946) occur in some places. (3) Prolific expansion of diatom populations, as is.indicated by the abundance of these fossils in some deposits, have been attributed to the enrichment of seawater by volcanic ash. The rea~ons for believing this have been reviewed by Taliaferro (1933) and Bramlette (1946 ). (4) Opal or cristobalite in the fuller's earth and elsewhere in Miocene rocks is similar to material in other regions that has been considered as possibly originating from ash (Hathaway
35

and others 1970, p. 17; Heron and Johnson, 1966, p. 59-62). However, a nodule of amorphous silica from the fuller's earth investigated by scanning electron microscopy (Pollard and others, 1971) apparently formed from silica released by the dissolution of diatoms and not from ash.
Though the foregoing paragraph outlines reasons for assuming that volcanic ash was present in the parent materials of the fuller's earth, insufficient evidence could be found to support a conclusion that the deposits formed primarily from this material. No volcanic shards, the well-known criterion for recognizing bentonite, were found by the author during the examination of several thin sections and many powder mounts of the fuller's earth with a petrographic microscope. However, shards would be difficult to identify if present, because many deposits contain isotropic shardlike fragments of diatoms that resemble volcanic shards. The diatom fragments, as noted by Grim (1970, p. 501), have been misinterpreted as being of volcanic origin, and Espenshade and Spencer (1963,p. 20-2.1) also commented on the misidentification of shards.
The conclusion that the fuller's earth did not form primarily from ash is essentially the same as that reached by Kerr (1937, p. 548), who stated "A significant microscopic feature of the Attapulgus clay is the absence of relict structures indicative of volcanic origin. A large number of thin sections of fuller's earth from Attapulgus have been examined without revealing a single feature such as a shard, a flow line, a lithic fragment, or some other feature suggestive of volcanic origin." McClellan (1964, p. 98), after investigating the fuller's earth by X-ray and microscopic methods, also concluded that no support for the presence of large quantities of volcanic ash could be found. Furthermore, no anomalous concentrations of by major oxides and minor elements suggestive of volcanic origin are present in the fuller's earth, and no zeolite minerals have been found in the fuller's earth. Zeolite minerals, particularly clinoptilolite, in Miocene and other Tertiary beds in the Coastal Plain have been thought to be suggestive of volcanic ash origin (Rooney and Kerr, 1964, p. 735; Heron and Johnson, 1966, p. 60-61; Reynolds, 1970, p. 834; Towe and Gibson, 1968).
As volcanic ash apparently was not the major parent material of the palygorskite, the most likely source of silica and aluminum required seems to be silicate minerals and dissolved matter in solution carried by streams. For several reasons, which have been summarized by Hathaway and others (1970, p. 21), silica and aluminum transported from land areas would not be expected to enrich the water of the open ocean. However, conditions in the restricted environment in which the palygorskite and associated dolomite formed would be quite different from those in the open ocean. A chemical environment in which penecontemporaneous dolomite formed was probably also the type that would allow the concentration of introduced silica and aluminum.
The montmorillonite and kaolinite in the fuller's earth are among the silicate minerals most likely to have been introduced by streams, but montmorillonite may have formed in place by halmyrolysis and both apparently have also formed from palygorskite during weathering. Probably most of the montmorillonite intermixed with palygorskite and sepiolite either was deposited as such or formed penecontemporaneously with these clay minerals. However, much of the montmorillonite in the upper part of fuller's earth deposits under thin overburden seems to have formed during weathering from palygorskite and sepiolite, a fact which was first recognized by Gremillion (1965b, p. 54-72). He proposed the following sequence of weathering-palygorskite-montmorillonite-kaolinite. The evidence for this sequence of weathering is montmorillonite is far more abundant in the upper parts of deposits than in the lower parts, and it tends to be much more abundant in deposits under light overburden than in deeply buried ones. Furthermore, the close association of palygorskite and montmorillonite in several different types of rocks in other regions indicates that these minerals are related in origin. Apparently either mineral can form from the other, if the required chemical environment exists. This conclusion is supported by the observations of Paquet and Millot (1972, p. 258-259), who summarized data which indicate that palygorskite is unstable in soils and commonly alters to montmorillonite. Kaolinite occurs mainly in the uppermost parts of deposits. In the northern part of the district, the uppermost parts of some deposits under thin porous overburden contain few clay minerals other than
36

kaolinite. The formation of this kaolinite from montmorillonite is indicated by the gradation of the kaolinite-rich zones downward through zones in which these minerals are mixed and into zones containing mainly montmorillonite and little or no kaolinite. This evidence for the formation of kaolinite from montmorillonite is identical with that found by Altschuler, and others (1963) in the Bone Valley and Citronelle Formations in central Florida.
PREPARATION OF THE FULLER'S EARTH FOR MARKET
MINING
Mter a suitable fuller's earth deposit has been proved by drilling and testing, the first step in mining is the removal of the overburden. Bulldozers and scrapers are used for this purpose by all companies active in the district, and one company uses a large walking dragline powered with electricity to do much of its stripping. Thicknesses of stripped overburden range from a few feet to approximately 75 feet (23m) in most mines, but in some mines the maximum overburden removed along ridge lines is as much as 100 feet (30.5 m) thick. Most of the overburden is unconsolidated enough to be loosened with a bulldozer, but in the southern part of the district some of the overburden consists of limestone and cemented sandstone which must be blasted before removal with heavy equipment. In most mines, removal of overburden is done in panels, and after the earth in one panel is mined, the overburden from the next panel is dumped in the mined-out area. After stripping, the fuller's earth is loaded on trucks by dragline and hauled to the plant. In the early part of the century, mine trams were used for hauling, and some of the stripping was done by hydraulic methods, but neither technique has been used in recent years.
PROCESSING
The raw fuller's earth as it is delivered to the plant contains approximately 50 percent volatile matter, and some of it as much as 10 percent undesirable impurities. The volatile matter is chiefly free and combined water. The processing of fuller's earth involves mainly crushing or slicing the crude clay, drying or firing to drive off the volatile matter and improve the desired properties, grinding, grading by particle size, and packaging. According to Oulton (1965, p. 5), more than 90 different commerical grades and products, each with its own specific properties and applications, are made by varying the raw material and processing. One plant uses an extruding process before drying to improve the properties for certain products. In this process, the crushed clay is fed into a pug mill, and water is added to obtain the desired plasticity. It is then extruded into rods which are approximately 1!2 inch in diameter.
Drying in most plants is done in gas- or oil-fired rotary dryers, which are as large as 10 feet (3m) by 65 feet (20m), but one plant uses a fluid bed-type dryer. The temperature at which the clay is dried ranges from 300 to 1200 Fin the different dryers, depending on the use of the product. The dried clay is ground in rod or other types of mills and sifted to yield a variety of granular and pulverized grades. Plants in the northern part of the district that produce mainly absorbent granules actually beneficiate their product by discarding the fines. This is possible because most of the impurities are in the sand and silt size and, therefore, are distinctly finer than the granular-size product. Plants in the southern part of the district, which produce many grades of pulverized fuller's earth as well as granular grades, commonly recycle their material and select their raw clay with considerable care. One of the products resulting from selective mining and processing is 95 percent finer than 10 microns in particle size; it is used for suspending agents and other purposes.
USES
The major uses of fuller's earth produced in the United States in the period 1927 through 1971 are shown graphically in Figure 12. In the early part of this period, much of
37

1000 900 800

EXPLANATION

I

Otheruses Insecticides and fungicides Vegetable oils and animal fats Drilling mud Absorbent uses Mineral oils

700

(j)

z
0

600

f-

f0:: 0 I
(j)

lJ... 500 0

(j)
0 z
<( (j)
::l 0 400 I f-

300

200

100

1930

1940

1950

1960

1970

Figure 12. Fuller's earth sold or used by producers for specified use, 1927-1971, compiled from U.S. Bureau of Mines Minerals Yearbooks.
38

the fuller's earth produced in the Attapulgus and Quincy parts of the district was sold for bleaching or clarifying lubricating oils. The decline of this market began just prior to World War II when more efficient catalytic cracking and improved processing of petroleum expanded. The most notable increase in fuller's earth markets in the 1960's and 1970's was in absorbent granules. Nearly one half of the large tonnage of absorbent granules produced in the United States is processed in this district. The insecticide-fungicide use also has been increasing rather steadily in recent years. Virtually all the fuller's earth used as drilling mud is the palygorskite (attapulgite) type mined in the southern part of the district. This type clay provides a drilling mud that is superior to bentonite where "salt formation" is encountered in drilling; however bentonite makes a superior mud where the rocks penetrated contain only fresh water.
The foregoing discussions apply only to those uses consuming sufficient quantities of fuller's earth to be classified separately by the U.S. Bureau of Mines in the Minerals Yearbooks. In addition, fuller's earth is or has been produced for many miscellaneous uses. Some of these are: pharmaceuticals designed to absorb toxins, bacteria, and alkaloids in the treatment of dysentery, purification of water and dry-cleaning fluids, dry-cleaning powders an.d granules; manufacture of NCR (no carbon required) multiple-copy paper, manufacture of wallpaper; extenders or fillers for plastics, paints, and putties. Fuller's earth mined near Ellenton, Fla., was used for making lightweight aggregate for the construction of concrete barges during World War II. Still other uses of fuller's earth and its suitability for uses in new products are outlined by Haden (1963), Haden and Schwint (1967), and Haas (1970, 1971). Some reports also note that fuller's earth is used in making cement. Probably the basis of these reports is the mining of the Twiggs Clay near Clinchfield, Ga., and its use in making portland cement. It is used for this purpose mainly to obtain the desirable chemical composition in the clinker from which the cement is made. The classification of this clay as fuller's earth results from the fact the Twiggs Clay is mined for fuller's earth near Macon, Ga., and this formation is widely known in Georgia as a fuller's earth.
PRODUCTION
Records of production of fuller's earth in the Meigs-Attapulgus-Quincy district are not available; however, the total output can be estimated on the basis of the national leadership of this district and figures available for the total output of all districts in Georgia and Florida. These two states have led the Nation in domestic production of fuller's earth since 1895. They produced 72 percent of the national total during the period 1895 through 1971, which was 20.3 million tons valued at more than $375 million. The total fuller's earth production of Georgia and Florida during this period was about 14.7 million tons, having a value of nearly $300 million. The value per ton is higher than the national average, because in most years the palygorskite (attapulgite) fuller's earth from the southern part of the MeigsAttapulgus-Quincy district sold for $2 to $4 a ton more than fuller's earth from other districts. Other fuller's earth districts are presently active in both Georgia and Florida, and still others have been active intermittently in the past; therefore, the total production for Georgia and Florida does not apply directly to the Meigs-Attapulgus-Quincy district. However, this district has been the major fuller's earth producer in these two States and can be assumed to have supplied 80 percent of the total for these States. On this assumption, the total fuller's earth produced in the Meigs-Attapulgus-Quincy district has been approximately 11.7 million tons, and the value probably has been more than $230 million.
The following companies operate seven plants producing fuller's earth in the MeigsAttapulgus-Quincy district: Waverly Mineral Products Co., Meigs, Ga., Pennsylvania Glass Sand Corp., having plants at Quincy, Fla. (operated under the name Floridin Co.), Havana, Fla. (formerly owned by Dresser Minerals Division of Dresser Industries, Inc.), and at Ochlocknee, Ga. (formerly owned by Thor Mining Co.); the Oil-Dri Corporation of America owns a plant completed at Ochlocknee, Ga., in 1971 and formerly operated a plant under the name of Cairo Production Co., near Cairo, Ga.; the Minerals and Chemicals Division of Englehard Minerals and Chemicals Corp. and Milwhite Co., Inc. have plants at Attapulgus, Ga. One of the newest plants in the district was built by Cherokee Industries, Inc. at Ochlocknee,
39

Ga. This plant was acquired by the Control Packaging Company, and it ceased operation in the summer of this year. Fuller's earth plants which have been dismantled were formerly operated at six other localities in the district.
40

FIELD TRIP- FULLER'S EARTH IN THE MEIGS-ATTAPULGUS-QUINCY DISTRICT, NOVEMBER 16, 1974

Mileage Interval Cumulative
0.0

33.0

33.0

75.0

108.0

25.2 1.4
18.3 0.6
2.6

133.2 134.6 152.9 153.5
156.1

Leave Ramada Inn, 7:30a.m., proceed north to Pierce Ave. access ramp and south on Hwy. I-75. South of Macon, the route extends across a broad belt of strata of Late Cretaceous age. The contact with overlying Tertiary beds is approximately 10 miles south of Macon.
Perry, Ga. The Medusa Portland Cement Co. plant is at Clinchfield, about 6 miles to the east. It is the only cement plant in the Coastal Plain of Georgia. The cement is made from the soft Eocene Ocala Limestone (Tivola Tongue of the Georgia Geological Survey). Clay from the Twiggs Clay, which overlies the limestone, and kaolin are added to obtain the proper silica and alumina content of the cement.
The Ocala Limestone underlies the region south of Perry. It has been leached throughout most of its outcrop belt, but its position is marked by residuum. Clayey beds (Twiggs Clay?) occurring above the limestone can be seen in several roadcuts.
Tifton, Ga. Leave Hwy. 1-75 and proceed south on U.S. Hwy. 319 (Fig. 13). The Tifton Upland, named for this place, is the upland plain that extends over much of the Georgia Coastal Plain. This same surface is somewhat more dissected in Florida and is called the Tallahassee Hills in that state.
Moultrie, Ga. Turn right (west) at corner of courthouse square and proceed straight ahead at Ga. Hwy. 37.
Road junction Ga. Hwy. 37 and Ga. Hwy. 111. Turn left on Ga. Hwy. 111.
Crossroads Ga. Hwy. 111 and U.S. Hwy. 19. Proceed straight ahead on Ga. Hwy. 111.
Crossroads Ga. Hwy. 111 and Ga. Hwy. 3 in Meigs, Ga. Turn left (south) on Ga. Hwy. 3. If turn is missed, turn left at next intersection (1 block farther) and continue south.
Turn left to Waverly Mineral Products Co. plant. STOP 1. Absorbent granules are produced in this plant by two systems. A. Double-pass drying From mine by truck to hopper at plant-+ shredder-+ raw-clay storage-+ secondary crusher (double-saw shredder)-+ fluid-bed drier (250 F)-+ fluid-bed cooler (150 F)-+ conveyer to screen house (through scalper to remove fines) then ground and screened to -8/-30 mesh-+ rotary kiln (1000 -1300 F)-+ cooler (125 F)-+ finished-product bins.
41

. . - -- - -- .".%....j
(JQ ~ '"I (!)
~
CA:I

~ 0
.~...
(!)

$1'

:p:l..

,j:::..
1:..:>

.".'..
0 "0
".0..'..

-E:
(!) '"I
"'~

(!)
:~..:.r.
-...........
(!)
p..

.~o

-

0-

-

... .

--

- - ~ -

~ Active mine - trip stop
! Fuller's earth plant

WMP OD CP TH -
MC EMC FC

Waverly Minerals Products Co. Oil-Dri Corporation of America Control Packaging Co. Thor Mining Co. (Pennsylvania
Glas Sand Company, Inc.) Milwhite Company, Inc. Englehard Minerals and Chemicals, Inc. Floridin Division Pennsylvania Glass
Sand Company, Inc.

west Q
4l ' 'E ,,UK
~
\

''c

E

Mileage Interval Cumulative

2.8

158.9

0.2

159.1

1.3

160.4

1.3

161.7

0.4

162.1

0.5

162.7

B. Single-pass drying Raw-clay storage-)- double-roll crusher~ rotary drier (750 F)~ coolex (150F) ~ screen house number 2 (through scalper to remove fines) -7 eorrugated rolls and hammer mill~ screened to -8/-30 mesh....,.. finished-product bins.
All absorbent granules produced here are packaged in doublewalled paper bags ranging from 4- to 50-pound capacity. Shipment is by rail and huck.
The four active plants in the Meigs-Ochlocknee, Ga., area produce mainly absorbent b1Tanules. They are sold for floorsweep-type granules for absorbing oil, grease, chemicals, etc.; animal litter, soil conditioners, etc. Occasionally, a seasonal herbicide carrier that is -8/-15 mesh is produced.
Leave Waverly Mineral Products Co. plant and proceed left (south) on Ga. Hwy. 3.
Oil-Dri Corporation of America plant. Turn left into plant area. LUNCH STOP.
Leave plant and proceed left (south) on Ga. Hwy. 3.
Control Packaging Co. plant on left.
Turn right on county black-top road (at Sing filling station). The packaging and shipping installations of Thor Mining
Co. (Pennsylvania Glass Sand Co.) are along the railroad about 0.5 mile straight ahead.
The Dawes Silica Mining Co. plant is 5 miles farther south on Ga. Hwy. 3. The products, processed by washing heavy-mineral separation, and screening, includ glass sand, foundry sand, construction sand, and silica flour. The sand is dug from pits in terrace deposits along the Ochlockonee River.
Turn right (north) on county black-top road.
Thor Mining Co. plant on right. The plant is in an area that has been mined and backfilled. Absorbent granules made here are trucked to the packaging plant in Ochlocknee.
Oil-Dri Coporation of America, Inc., fuller's earth mine is on the right (east). Thor Mining Co. mine is on the west side of the road.
STOP 2

43

Mileage Interval Cumulative

Rock description

Thickness

Mineral estimates (in parts of 10; Tr., trace)

.E.,

Feet Inches

:E.;;;
~

1?.

~

0..

E
]
0.
Jj

;

-~
E

:Ee

" 0
;:!=!

0
~ "

!; j
"0'

;
~
:rB::

~
0
8

[Total thickness of fuller's earth, beds 7-12, is 32 ft. Altitude of top of bed 8 is 239 ft.]

I. Soil, brownish-gray, sandy-----------

10

Miccosukee Formation (?)

2, Sand, gray in lower part, yellowish brown in middle, and reddish brown and weathered in upper part; mostly fine to medium grained and clayey but contains

some lenses of ver)' coarse sand; lower part in lenticular units and channel-fill

deposits ---- 25

Hawthorn Formation

3 Clay, pale-.vellow i5Y 7/4), plastic ----- --- -- - -- -- - 5-8

rr.

~ Sand, light-gray (5Y 7/2), ver)" clayey - --- 1-1'!2

5. Clay, like 2 --- - - - -- - 6. Sand, like 4 - --- - - ---- - --- - ---- - -- 7. Cia), pale-yellow i5Y 7/ 4), plastic, diatoms and silicoflagellate remains common
!stripped with overburden) . _.. .. _. _. _. _. _. _. _. _. _. _. _. _. _. _. .... --.-- . .
8, Cia), li~ht-gra) i5Y 7/2), massive, jointed; black manganese (?) and yellow films alon~ joints; softer than lower cia); diatoms abundant--------

7 1 1h -2

5

2

Tr.

2

9. Clay, light-gray (5Y 7/2), tough, interbedded with sand-clay-pebble beds; clay beds

range from 2 in. to 1 ft in thickness, sand-clay-pebble beds are as much as 2 in.

thick; diatoms abundant, sponge spicules and silicoflagellate remains common

Samples:

Clay _ . . ---- . . . -- - -- - ___ --- - - -- .....

1

Clay pebbles ---- ---- -- -- ----------------- ----------------- . .. ---- - Tr.

10. Clay, light-gray (5Y 7/2), massive, tough, jointed; diatoms abundant

4

8

I

11. Clay, light-gray (5Y 7/ 2) massive, tough, jointed; contains a few sand lenses \-'l X 8

-- ---- - ----

I

G

3

4

Tr. 5

Tr,

2

2

Tr

3

Tr. Tr. - ----- 2 I - -- -

in . in upper half; diatoms abundant, sponge spicules and silicoflagellate remains

common . -----------------.------------------------------------------- n

Tr.

Tr.

12. Clay, light-gray (5Y 7/2), massive, tough, jointed; black manganese (?) films

along joints; diatoms abundant, sponge spicules common ...

Samples: Upper 4ft---------------------------- -- -------------- ---- ----

,,. 5

,,. 2

Lower 1ft . ------------------------- - - - -------------- - ------ -------

Tr.

6

2

------------------------------------------------- Sand, light-gray (5Y 7/2), fine-grained, hard.----------------------. ----- ------

Total measured .. ----- -- - . . . . . .... 74 10

Section of fuller's earth and overlying beds exposed in Oil-Dri Corporation of America mine.

0.9

163.6

Return to county road junction and tum right (west).

5.4

169.0

Road junction. Tum left (south) on Ga. Hwy. 111.

6.7

175.7

Turn right (west) at water tower on north edge of Cairo,

Ga. (if turn is missed, proceed 8/10 mile and turn right on

U.S. Hwy. 84).

0.7

176.4

Road junction. Enter U.S. Hwy. 84 at angle and proceed

west on this highway.

2.2

178.5

An inactive fuller's earth plant is on railroad 1.7 miles to the

south.

4.5

183.1

Whigham, Ga. Continue west on U.S. Hwy. 84.

6.6

189.7

Climax, Ga.

Note: If rainy day, turn left (south) on Ga. Hwy. 262 and

proceed on alternate rainy-day route.

44

Mileage Interval Cumulative

7.0

196.7

2.4

199.1

14.2

213.3

0.5

213.8

1.5

215.3

Turn left (south) on bypass around Bainbridge, Ga.
Turn left (southeast) on Ga. Hwy. 309.
Crossroads Ga. Hwy. 309 and Ga. Hwy. 241. Continue straight on Ga. Hwy. 309.
Two fuller's earth plants (Milwhite Co., Inc., and Englehard Minerals and Chemicals Inc.) are at Attapulgus, Ga., 4 miles northeast of the road junction. Plants operated by Floridin Division of Pennsylvania Glass Sand Co. are at Quincy, Fla., 10 miles to the southwest and at Havana, Fla., 10 miles to the southeast.
Fuller's earth produced in the southern patt of the district consists mainly of attapulgite. Many products including drilling mud, insecticide and fertilizer carriers, fillers, bleaching materials, absorbents, etc., are produced from this clay.
Enter Florida. Continue straight on Fla. Hwy. 159.
Turn right (south) on black-top to Englehard Minerals and Chemicals, Inc., La Camelia mine.
STOP3
The LaCamelia mine area extends over 660 acres. About 3% million tons of raw palygorskite (attapulgite) fuller's earth have been produced here since the first mining in 1954. The dragline used for stripping has a 160-foot boom and a 7-yard bucket. The relatively small bucket is used with the long boom to obtain casting distance.

45

Rock description

T hickn ess

.Mineral es ti ma tes (i n pa rts of 10; T r ., t race)

a

~

:

Feet Inches ~ 6
-">;;'.

.~ 0
~

0..

lfJ

~
c E
::0;

~
:~ 0
~"'

~

Jj
~

."t,i'l'

"0'

~

!!1

!;!:1;

'i3
0

-;;

0

u

Q

[Thickness of clay, bed 21, where not cut by channel fill, 10ft; beds 27-30, 9 ft 10 in. Altitude of top of bed 21 is 187 ft]

-:;~;
Q,

!;!1;

:!
0

~

c";:

:":;

I. Soil, dark-brownish-gray, sandy-------------------------------------------Miccosukee Fonnatfon (!)

2. Sand, rrddish, rlayey, nonbedded, weathered--------------------------------

3. Clay and sand inlerhedrled, liKhH!ray anrl brown variegated; contains scattered

while and light-gray chert norlulcs; lhicknc8s irregular--------------------- 1-3

4. Sand, brownish-red, rine- to medium-grained. massive; contains burrows of Cullintlfl.'>,'m; thickness irrc~ular __________________________________________ _
5. Sand and clay interbedded; sand is brownish red, mainly medium grained but con-

1-2 -- - ~- - - - -- - - -- - -- - - - -- --

tains some gravel; clay is light gray and yellowish gray; thickness irregular._ 1-2 - - ---- - -- -- - -- - -- -- -- - --6. Sand, brownish-red, cross bedded; mainly coarse grained with some gravel in upper

part; contains a few burrows of Callimurs:w ------------------------------- 18 7. Nodular zone consisting: of spheroidal wavellite concretions 11.! to 2 in. in diameter;

concretions coalesce to form a ledKC 4 to 6 in . thick-----------------------8. Sand, reddish-brown, medium to very coarse ~rained; most grains coated with red
iron oxide; cross bedded _________________________________________________ _
Hawthorn Fnrmatiun

12 - - - --- -

9. Sand and clay interbedded, mostly yellow 1!OYR 7181: lower part cross bedded, contains black lithiophorite accumulations alan~ bedding; clay abundant in lower

part, where beds are as much as 2 in. thick; clay higher in unit is mostly in

laminae; uppermost zone 1 to 2ft thick is weathered white and consists of fin egrained sand and kaolin, indicatin~ an unconformity-----------------------
Samples:

30 -- - ----

While weathered zone at top--------- - ------------------------------- - ----- - ---- -

6

Clay bed in lower parL--- - -- - ---------------------------------------- -- ---- ----- -

3

10. Sand, brownish-yellow (IOYR 6/ 81, Cine-grained, very clayey, poorly bedded____ 4

11 . Sand, light-gray i!OYR 7/ 21, ver.v fine grained, nonbedded____________________ 14

12. Limestone, light-yellowish-brown (!OYR 6/ 41, sandy, soft_____________________ I

13. Limestone, light-yellowish-brown (2.5Y 6/ 41, hard, ver; sandy; consists mainly of

internal molds or fossils, contains lar)l(e Pt>cfeu ; brown and gray phosphate

pellets common ------------ ___ ------- ___ --------------------------------

14. Limestone, light-yellowish-brown (IOYR 6/4), very sandy, sort---------------15. Limestone, light-gray (5YR 6/ 1), soft, fossilierous ___________________________ _

16. Limestone, light-gra; (5Y 6/1), hard, phosphatic, sandy: a persistent zone or black muck or Kel occurs in vugs and cracks in upper part; contains abundant marine fossils; Sorite.~ present ________________ __________________________________ _

17. Clcaayl,c1_lmeovree1_nhslue__t_h_a_n__g_r_a_y__(_5_Y__5_/ll,__h_a_r_d_;__c_o_n_t_a_in__s__ir_re__g_u_la_r__b_o__x_w_o_r_k__o_f__w_h_it_e_ 2

4

5

18. Sand, dark-greenish-gray, clayey; contains abundant marine fossils ___________ _ I

8

19. Sand, dark-grcenish-l{fay, clayey------------------------------------------- ~

6

20. Clay, more blue Lhan Kray (5Y 5/11. hard: contains irregular boxwork of white calcite veins ________________________________________________________ . __

Sample:

Clay _----------- _____ . _____ ---- _--------- __ ----------- ____ . ________ --- --- _ - ----

Tr.

2L Cia.\', most!.\ olhe gray (5Y 6/ 2), hard: contains two persistant layers of while

chalky dolomite 2 to 4 in. thick in upper part; cut by irregular channel-fill-type

lenticular deposit The lenticular deposit is composed or fine to very coarse sand units and carbonate and phosphatic ma terials, and has burrows of Crlllimm.'>.w; rillin~s of burrows contain Foraminifera of Chiopla age (middle Miocene) ___ _ 10

Samples:

CChlaalyky---d-o-lo-m--i-te--_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_--_-..-__--_-__-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_- --- _-__--_

8 I

Tr

22. Limestone, pale-yellow (5Y 8/31, abundant black clay films along joints: thickness irregular _________ _. ___ .. ___ ------- _______ ------ ____________ . _ ~ I

Sample: Cla.1 film ____ .---------- ____________________________________________ _. - --- __ - -- -- - ~- - - - - ---- -

23. Clay, pale-olive (5Y 6/3); minor black mangancse(~)stains along joints; contains

scattered aiKal heads consisting of\\ hitc chalk) dolomite as much as 11':: in thick

and crystals of a carbonate min era i-----------------------------------Samplcs:

Cla.1 ---------------- - - -- ----- - ---------------------------------- -------

Oolomitc rorming algal head- - --- - - - ------------------------------ - -- -- - -- ....... ..

24. Cia.\, lil!ht-gra)' I5Y 7/ 21, hard ; contains phos phate nodules: a la)er of \\' hitc chalky

dolomilc occurs in upf)Cr part . . _______ ______________________________ .. . .. ___ __.,. 8

6

I

2

5

25. Sandgtone, white I&Y 8/ 21. mos t!,, Cint' grained, calcite-cemented; co ntains

phosphat' nodules, fish remains, and scattNcd chunks or clay-------------

26 Cia.\, pale-oli\'e (5Y 6/ 3J; somewhat darker in upper part: upper contact irregular,

upper part contains stringers of O\~crlyinJZ sandstone, appears churned b~

burrowing marine animals, probably Callitll/u.~.w'---------------------------

10

21. Clay, gray f5Y 5/1); contains much black organic matter, plastic; has brecciated appearance __________________ . __ __ . ____________________________________ - - - -- - 10

28, Clay, pale-olive i5Y 6/31 in lower part,i(l'a;- (5Y 5/1) in upper part: plastic: some

black organic stains near hase ------- - -------------------------------- - 29, Clay, li~ht-Kra,r i5Y 6/21, plastic ___________________________________________ _

30. Cla)T, gray f5Y f)lll, plastic; con rain~ t\\-0 '' hitc chalky dolomite zones 1 to 4 in

thick, one zone ncar base and one 1 ft ahoYe base; a few small sand lenses 1to 10
in. thick in upper parl ------------- -- .. - - r ---- --- - ---
Samples:

ClaY---------------------------- - - - - - -- -- - -- - - - -- --- - - - -- --- - --- -- - - - -- - --- - - - 1

'rr

Chalky dolomite----------------- ---- -- --- -~- --- - - -- - - - -- - - -- ---- - - - -- ---- 2 ---- -- - -- - - - - -- ---- -- --- -- -------

31 Sandstone, white i5Y 8/ 2), hard, claye; - - - - -- - -- -- ----- ----- - ---~- - - - -- --- - - - - --- -- -- -- - -- -- ~-- - --- -- -- --- ---- ------- -------

Total measured (rounded).- ---- ..... __ .. _.... .. ..... ___ ______ ,. _-- -- - -- - - 14() -- ----- - -- - -- -- -- - -- - - - - -- - - ------ - ----- --- --- - - - ~- -- - - - -~--- ---- - -

Section of fuller's earth and overlying beds in La Camelia mine .

46

Mileage Interval Cumulative

3.3

218.6

3.3

221.9

1.0

222.9

4.1

227.0

2.9

229.9

9.4

239.3

Return to Fla. Hwy. 159. Turn right (east).
This is the Jamieson area. An old inactive fuller's earth plant is on the north side of the highway. A large mine operated by the Floridin Division is on the right (south) side of the road. Fla. Hwy. 159A forks left. Stay on Fla. Hwy. 159.
Road junction. Turn left and then right on access road to U.S. Hwy. 27.
Turn right on U. S. Hwy. 27. This is Havana, Fla. One of the Floridin Division plants is located about a mile to the north. This plant was built by the Magnet Cove Barium Division, Dresser Industries, Inc., primarily to supply palygorskite (attapulgite) drilling mud.
Cross Ochlockonee River. A small naturally washed sand operation about a mile
upriver is active from time to time. A dragline bucket is pulled across the river beds. The sand is remarkably white quartz. One use of it is in cement-bonded brick. White portland cement is used, and the brick formed under pressure is an attractive white construction product.
Turn right on Fla. Hwy. 263 (truck route), continue on this highway passing under Interstate Hwy. I-10, crossing Interstate Hwy. I-90 at stop light, crossing Fla. Hwy. 20 at stop light, and one mile beyond Fla. Hwy. 20 make right tum at airport sign.
Tallahassee airport. Field Conference terminates.

47

ALTERNATE RAINY-DAY ROUTE FROM CLIMAX, GA.

Mileage Interval Cumulative

0.0

189.1

12.5

201.6

0.8

202.4

At Climax, Ga., turn left (south) on Ga. Hwy. 262.
Englehard Minerals and Chemicals, Inc., Block N mine on left. Large acreages have been mined and reclaimed. A pulpwood crop has been harvested recently as part of a thinning of reforestation project.
Englehard Minerals and Chemicals, Inc., Block M mine. ALTERNATE STOP 3 The section exposed in this mine is in a general way similar to the following one of fuller's earth and associated bed formerly exposed in the Block N mine.

Rock description

Thickness

Mineral estimates (in parts of 10; Tr., trace)

Jaj

Jj

Feet Inches

:.;;;
~

~

b

"0..

.~
0a
r"n

..2
15 0
E
"::0;:

:2s l
0
:".:

.,_

~
:s

~
~

0'

r..

Jj

2;:;l

'6
0

-;;;

0

u

Q

[Total thickness of clay measured, beds 5-7, is 15ft 6 in. Altitude of top of bed 6 is 173 ft]

1. Soil, dark-gray __________________________________________________________ _

Hawthorn Formation (?)

2. Sand, light-gray, fine- to medium-grained, weathered------------------------

2

3. Sand, brownish-gray, medium-grained, clayey-------------------------------

4

4. Limestone, white, very sandy; contains molds and casts of marine fossils -----

2

5. Clay, light-gray (5Y 7/1), plastic; burrows of Calliana.ssa or other marine animals

abundant and cause the clay to have a brecciated appearance; calcile-filled desic-

cation cracks abundant in upper 4 in. (stripped with overburden)-----------
6 Clay, light-gray (5Y 7/2), poorly bedded; contains a few white calcite crystals in lower part, black manganese(?) films along joints _______________________ _

7. Clay, light-olive-gray (SY 6/2), moderately hard, jointed; upper part contains a few

small lenses of light-gray silt and white ovoid lenses of limestone---------8. Sand, light-gray (SY 7/2), fine-grained, silty and clayey; upper part contains molds

of marine fossils Sample: 2 llm fraction _________________________ ----- _______________________ _

Tr.

5

2

Tr.

2

10

Total measured ----~----- - - ------- ------ --- ----------------

24

~
c. :!
0:s ~

.~
~
:::;s:

Tr

Section of fuller's earth and associated beds formerly exposed in Block N mine.

Continue on Ga. Hwy. 262.

1.7

204 .1

Highway junction. Turn left (southeast) on U.S. Hwy. 27.

1.3

205.4

Enter Florida.

5.3

210.7

Havana, Fla.

1.0

211.7

Return to fair-weather route mileage 222.6.

48

REFERENCES CITED
Altschuler, Z. S., Dwornik, E. J., and Kramer, Henry, 1963, Transformation of montmorillonite to kaolinite during weathering: Science, v. 141, no. 3576, p. 148-152.
Bates, T. F., 1964, Geology and mineralogy of the sedimentary kaolins of the Southeastern United States-a review, in Bradley, W. F., ed., Clays and clay minerals-Proceedings of the Twelfth National Conference ... 1963: New York, Macmillan Co., p. 177-194.
Bradley, W. F., 1940, The structural scheme of attapulgite: Am. Mineralogist, v. 25, no. 6, p. 405-410.
Bramlette, M. N., 1946, The Monterey Formation of California and the origin of its siliceous rocks: U.S. Geol. Survey Prof. Paper 212, 57 p.
Brooks, L. E., and Morris, H. H., 1973, Aluminum silicate, kaolin, in Patton, T. C., ed., Pigment hand book: New York, John Wiley and Sons, v. 1, p. 199-215.
Buie, B. F., 1964, Possibility of volcanic origin of the Cretaceous sedimentary kaolin of South Carolina and Georgia [abs.], in Bradley, W. F., ed., Clays and Clay MineralsProceedings of the Twelfth National Conference ... 1963, New York, Macmillan Co., p.195.
Buie, B. F., and Fountain, R. C., 1968, Tertiary and Cretaceous age of kaolin deposits in Georgia and South Carolina [abs.]: Geol. Soc. America Spec. Paper 115, p. 465.
Buie, B. F., and Gremillion, L. R., 1963, Attapulgite in fuller's earth deposits of Georgia and Florida: Georgia Mineral Newsletter, v. 16, no. 1-2, p. 20-25.
Cooke, C. W., 1943, Geology of the Coastal Plain of Georgia: U.S. Geol. Survey Bull. 941, 121 p.
Cousminer, H. L., 1973, Paleogene palynology of basal Coastal Plain sediments, Irwinton district, Georgia [abs.] : Geol. Soc. America Abs. with Programs, v. 5, no. 7, p. 584-585.
Cousminer, H. L., and Terris, L., 1973, Palynology of Paleocene clays from Georgia: Am. Assoc. Stratig. Palynologist, 5th Ann. Mtg., Abs. of Papers.
Dall, W. H., and Harris, G. D., 1892, Correlation papers, Neocene: U.S. Geol. Survey Bull. 84, 349 p.
Eargle, D. H., 1955, Stratigraphy of the outcropping Cretaceous rocks of Georgia: U.S. Geol. Survey Bull. 1014, 101 p.
Espenshade, G. H., and Spencer, C. W., 1963, Geology of phosphate deposits of northern peninsular Florida: U.S. Geol. Survey Bull. 1118, 115 p.
Gremillion, L. R., 1965a, Miocene near-shore deposits of attapulgite: Coastal Research Notes, no. 11, p. 11-12.
____ 1965b, The origin of attapulgite in the Miocene strata of Florida and Georgia, Florida State Univ., Ph.D. thesis, 139 p.
Grim, R. E., 1933, Petrography of the fuller's earth deposits, Olmstead, Ill., with a brief study of non-Illinois earths: Econ. Geology, v. 28, no. 4, p. 344-363.
49

REFERENCES CITED (Continued)
Grim, R. E., 1968, Clay mineralogy, 2d ed: New York, McGraw-Hill, 596 p.
1970, The texture and composition of bentonites: Israel Jour. Chemistry, v. 8, p. 501-503.
Haas, C. Y., 1970, Attapulgite clays for future industrial mineral markets [abs.]: Mining Eng., v. 22, no. 12, p. 63.
1971, Attapulgite clays for future industrial mineral markets: Soc. Mining Engineers of AIME, Centennial Ann. Mtg. New York, N.Y., Feb. 26-Mar. 4, 1971, Preprint No. 71-H-54, 13 p.
Haden, W. L., Jr., 1963, Attapulgite-Properties and uses, in Swineford, Ada, ed., Clays and clay minerals-Proceedings of the Tenth National Conference ... 1961: New York, MacMillan Co., p. 284-290.
Haden, W. L., Jr., and Schwint, I. A., 1967, Attapulgite-its properties and applications: Indus. and Eng. Chemistry, v. 59, no. 9, p. 58-69.
Hathaway, J. C., McFarlin, P. F., and Ross, D. A., 1970, Mineralogy and origin of sediments from drill holes on the continental margin off Florida: U.S. Geol. Survey Prof. Paper 581-E, 26 p.
Hendry, C. W., Jr., and Sproul, C. R., 1966, Geology and ground-water resources of Leon County, Florida: Florida Geol. Survey Bull. 47,178 p.
Hendry, C. W., Jr., and Yon, J. W., Jr., 1967,Stratigraphy of upper Miocene Miccosukee Formation, Jefferson and Leon Counties, Florida: Am. Assoc. Petroleum Geologists Bull., v. 51, no. 2, p. 250-256.
Heron, S.D., Jr., and Johnson, H. S., Jr., 1966, Clay mineralogy, stratigraphy, and structural setting of the Hawthorn Formation, Coosawhatchie district, South Carolina: Southeastern Geology, v. 7, no. 2, p. 51-63.
Herrick, S.M., and Vorhis, R. C., 1963, Subsurface geology of the Georgia Coastal Plain: Georgia Geol. Survey Inf. Circ. 25, 79 p.
Hinckley, D. N., 1961, Mineralogical and chemical variations in the kaolin deposits of the Coastal Plain of Georgia and South Carolina: Pennsylvania State Univ ., Ph.D. thesis, 194 p.
Illing, L. V., Wells, A. J., and Taylor, J. C. M., 1965, Penecontemporary dolomite in the Persian Gulf, in Pray, L. C., and Murray, R. C., eds., Dolomitization and limestone diagenesis-A symposium: Soc. Econ. Paleontologists and Mineralogists Spec. Pub. 13, p. 89-111.
Johnson, L. C., 1892, The Chattahoochee embayment: Geol. Soc. America Bull., v. 3, p. 128-132.
Jonas, E. C., 1964, Petrology of the Dry Branch, Georgia, kaolin deposits, in Bradley, W. F., ed., Clays and clay minerals-Proceedings of the Twelfth National Conference ... 1963: New York, MacMillan Co., p. 199-205.
Kerr, P. F., 1937, Attapulgus clay: Am. Mineralogist, v. 22, no. 5, p. 534-550.
50

REFERENCES CITED (Continued)
Kesler, T. L., 1963, Environment and origin of the Cretaceous kaolin deposits of Georgia and South Carolina: Georgia Mineral Newsletter, v. 16, nos. 1-2, p. 2-11.
Krynine, P. D., 1946, Microscopic morphology of quartz types, in Geologia, paleontologia, mineralogia e petrologia: Cong. Panam. Engenharia Minas e Geologia 2d, Rio de Janeiro, v. 3, p. 35-49.
Ladd, G. E., 1898, A preliminary report on a part of the clays of Georgia, Georgia Geol. Survey Bull. 6A, 204 p.
Longchambon, Henri, 1935, Sur des constituants mineralogique essentiels des argiles, en particulier des terres a foulon: Acad. Sci., Paris, Comptes. Rendus., v. 201, no. 10, p. 483-485.
McClellan, G. H., 1964, Petrology of attapulgus clay in north Florida and southwest Georgia: Univ. Illinois, Ph.D. thesis, 119 p.
Millot, Georges, Radier, Henri, and Bonifas, Marthe, 1957, La sedimentation argileuse a attapulgite et montmorillonite: Soc. Geol. France Bull., ser. 6, v. 7, no. 4-5, p. 425-433.
Neumann, F. R., 1927, Origin of the Cretaceous white clays of South Carolina: Econ. Geology, v. 22, no. 4, p. 374-387.
Oder, R. R., and Price, C. R., 1973, A brightness beneficiation of kaolin clays by magnetic treatment: Jour. Tech. Assoc. Pulp and Paper Industry [TAPPI], v. 56, no. 10, p. 75-78.
Oulton, T. D., 1965, Mining, production, and uses of attapulgite clay products: Am. Inst. Mining, Metall., Petroleum Engineers, Soc. Mining Engineers, Preprint 65H39, 10 p.
Paquet, Helene, and Millot, Georges, 1972, Geochemical evolution of clay minerals in the weathered products and soils of Mediterranean climates: Internat. Clay Conf. [A.I.P.E.A.] Madrid, June 25-30, Preprints, v. 1, p. 255-261.
Patterson, S. H., in press, Fuller's earth and other industrial mineral resources of the MeigsAttapulgus-Quincy district, Georgia and Florida: U.S. Geol. Survey Prof. Paper 828.
Patterson, S. H., and Murray, H. H., in press, Clays, in Lefond, S. J. and others, eds., Industrial minerals and rocks (nonmetallics other than fuels): 4th ed., New York, Am. Inst. Mining, Metall., Petroleum Engineers.
Pickering, S.M., Jr., 1971, Lithostratigraphy and biostratigraphy of the north-central Georgia Coastal Plain: Georgia Geol. Soc. 6th Ann. Field Trip, Oct. 8-9, 1971, 8 p.
Pollard, C. 0., Jr., Weaver, C. E., and Beck, K. C., 1971, Anatomy of a silica nodule [abs.]: Geol. Soc. America Abs. with Programs, v. 3, no. 5, p. 340-341.
Pressler, E. D., 1947, Geology and occurrence of oil in Florida: Am. Assoc. Petroleum Geologists Bull., v. 31, no. 10, p. 1851-1862.
Puri, H. S., and Vernon, R. 0., 1964, Summary of the geology of Florida and a guidebook to the classic exposures: Florida Geol. Survey Spec. Pub. no. 5, 312 p.
51

REFERENCES CITED (Continued)
Rainwater, E. H., 1956, Geology of Jackson County, Florida, by Wayne E. Moore [a review]: Am. Assoc. Petroleum Geologists Bull., v. 40, no. 7, p. 1727-1729.
Rateev, M.A., 1965, Modification degree of clay minerals during the stage of sedimentation and diagenesis of marine deposits, in Rosenquist, I. Th., and Graff-Petersen, P., eds., Internat. Clay Conf. Stockholm 1963, Proc.: New York, Pergamon Press, v. 2, p. 171-180.
Reynolds, W. R., 1970, Mineralogy and stratigraphy of lower Tertiary clays and claystones of Alabama, in Symposium on environmental aspects of clay minerals: Jour. Sed. Petrology, v. 40, no. 3, p. 829-838.
Rooney, T. P., and Kerr, P. F., 1967, Mineralogic nature and origin of phosphorite, Beaufort County, North Carolina: Geol, Soc. America Bull., v. 78, no. 6, p. 731-748.
Ross, C. S., and Hendricks, S. B., 1945, Minerals of the montmorillonite group, their origin and relation to soils and clays: U.S. Geol. Survey Prof. Paper 205-B, p. 23-79.
Scrudato, R. J., and Bond, T. A., 1972, Cretaceous-Tertiary boundary of east-central Georgia and west-central South Carolina: Southeastern Geology, v. 14, no. 4, p. 233-239.
Shinn, E. A., Ginsburg, R.N., and Lloyd, R. M., 1965, Recent supratidal dolomite from Andros Island, Bahamas, in Pray, L. C., and Murray, R. C., eds., Dolomitization and limestone diagenesis-A symposium: Soc. Econ. Paleontologists and Mineralogists Spec. Pub. 13, p. 112-123.
Siffert, Bernard, and Wey, Raymond, 1962, Synthese d'une sepiolite a temperature ordinaire: Acad. Sic., Paris, Comptes. Rendus., t. 254, p. 1460-1462.
Smith, R. W., 1929, Sedimentary kaolins of the Coastal Plain of Georgia: Georgia Geol. Survey Bull. 44, 482 p.
Taliaferro, N. L., 1933, The relation of volcanism to diatomaceous and associated siliceous sediments: California Univ. Dept. Geol. Sci. Bull., v. 23, no. 1, p. 1-56.
Toulmin, L. D., 1952, Sedimentary volumes in Gulf Coastal Plain of United States and Mexico. Part II, Volume of Cenozoic sediments in Florida and Georgia: Geol. Soc. America Bull., v. 63, no. 12, pt. 1, p. 1165-1176.
Toulmin, L. D., and LaMoreaux, P. E., 1963, Stratigraphy along Chattahoochee River, connecting link between Atlantic and Gulf Coastal Plains: Am. Assoc. Petroleum Geologists Bull., v. 47, no. 3, p. 385-404.
Towe, K. M., and Gibson, T. G., 1968, Stratigraphic evidence for widespread late early Eocene volcanism, eastern North America [abs.] : Geol. Soc. America, Ann. Mtg., Mexico City, Mexico, Nov. 11-13, 1968, Program with Abstracts, p. 299-300.
Uchupi, Elazar, 1966, Map showing relation of land and submarine topography, DeSoto Canyon to Great Bahama Bank: U.S. Geol. Survey Misc. Geol. Inv. Map I-475.
U.S. Bureau of Mines, 1928-1934, Mineral resources of the United States, 1924[-1931]: Washington, D.C., U.S. Govt. Printing Office (annual publication; continued by U.S. Bur. Mines, Minerals Yearbook).
1933-to date, Mineals Yearbook [1932- ] :Washington, D.C., U.S. Govt. Printing Office (annual publication).
52

REFERENCES CITED (Continued) Veatch, Otto, 1909, Second report on the clay deposits of Georgia: Georgia Geol. Survey
Bull. 18, 453 p. Vernon, R. 0., 1951, Geology of Citrus and Levy Counties, Florida: Florida Geol. Survey
Bull. 33, 256 p. von der Barch, C. C., Rubin, Meyer, and Skinner, B. J., 1964, Modem dolomite from South
Australia: Am. Jour. Sci., v. 262, no. 9, p. 1116-1118. Weaver, C. E., and Beck, K. C., 1972, Vertical variability in the attapulgite mining area, in
Puri, H . S., ed., Proceedings 7th Forum on Geology of Industrial Minerals, Tampa, Fla., April 28-30, 1971:'Florida Bur. Geology Spec. Pub. 17, p. 51-90. Wollast, Roland, Mackenzie, F. T., and Bricker, 0. P. ~ 1968, Experimental precipitation and genesis of sepiolite at earth surface conditions: Am. Mineralogist, v. 53, nos. 9-10, p. 1645-1662. Yon, J. W., Jr., 1965, The stratigraph_ic significance of an upper Miocene fossil discovery in Jefferson County, Florida: Southeastern Geology, v. 6, no. 3, p. 167-176.
53

..