Pulaski, Houston, Bleckley, Laurens, Johnson, Emanuel, Bulloch, and Screven Counties as well as most 

 of Jenkins and Candler Counties. Lithologically, the Cooper Marl is a cream to light-gray, somewhat 

 sandy, rather loosely consolidated, glauconitic, rather abundantly fossiliferous marl, i tie downdip lime- 

 stone facies of the upper Eocene in Georgia is the Ocala Limestone, which is composed of two kinds of 

 limestone. The upper division is composed of flat white, highly calcitized and somewhat saccharoidal, 

 porous, abundantly fossiliferous limestone. It occurs as a wedge that pinches out inland somewhere in 

 the second tier of counties, as for example in eastern Effingham and Bulloch Counties. The lower part 

 is found throughout the subsurface of the Coastal Plain wherever the Ocala Limestone is present and 

 consists of cream, somewhat granular, much calcitized, sparsely glauconitic, sandy (at depth), fossili- 

 ferous limestone. On the basis of lithology as well as paleontology, the outcropping Ocala Limestone in 

 Georgia is representative of the lower division, the upper division not extending this far updip, as noted 

 above. Like the Oligocene limestones the limestone facies of the upper Eocene is composed, through 

 secondary alteration, of light to dark-brown, recrystallized, saccharoidal, dolomitic limestones in south- 

 western and extreme southern Georgia. In eastern Mitchell and Decatur Counties, and in Grady and 

 Thomas Counties, the top of this stratigraphic unit has been arbitrarily picked in wells on the first 

 appearance of dark-brown dolomitic limestones. These upper Eocene dolomitic limestones are only 

 partially dolomitized in Brooks, Lowndes, Echols, and Clinch Counties, where the top of this unit may 

 usually be picked on the basis of appropriate Foraminifera. Thicknesses of the upper Eocene vary from 

 a few feet in the area of outcrop to over 700 feet. 



A few of the more important publications on the upper Eocene Foraminifera include articles by Cush- 

 man and Applin (1926), Cushman (1935 and 1945), Gravell and Hanna (1938), Howe and Wallace (1932), 

 Cole (1944 and 1945), and Puri (1957). The Foraminifera of the upper Eocene are the most abundant and 

 distinctive of any Tertiary unit in the Coastal Plain of Georgia. Moreover, both the Twiggs Clay member 

 of the Barnwell Formation and the Cooper Marl contain excellent assemblages of the smaller Foramini- 

 fera. The Ocala Limestone contains the most abundant foraminiferal faunas of any formation in the 

 Coastal Plain. In downdip areas, where the upper division is present, this limestone is composed almost 

 entirely of fossil remains such as molluscan shells, small brachipods, echinoid spines, bryozoan remains, 

 ostracods, and Foraminifera. The lower division of the Ocala Limestone is not as abundantly fossiliferous 

 as is the upper part but it contains many more of the larger foraminiferal species. Of the outstanding 

 guide fossils of the upper Eocene in Georgia, those from the Twiggs Clay Member of the Barnwell For- 

 mation include Textularia hockleyensis Cushman and Applin, Valvulineria jacksonensis Cushman, Nonionella 

 hantkeni (Cushman and Applin) var. spissa Cushman, and Hantkenina alabamensis Cushman. Those from 

 the Cooper Marl include Gaudryina jacksonensis Cushman, Marginulina cocoaensis Cushman, Bulimina 

 jacksonensis Cushman, and Eponides carolinensis Cushman. Those from the upper division oftheOcala 

 Limestone include Textular ia dibollensis Cushman and Applin var., i^ ianularia truncana (Gumbel), Lin- 

 gulina ocalana Puri, Operculinoides floridensis (Heilprin). Mississippiana monsouri Howe, Asterocyclina 

 nassauensis Cole, and Pseudophragmina flintensis (Cushman). In addition to these diagnostic Foramini- 

 fera at least one species of a small brachiopod, Argyrotheca wegemanni Cole , often occurs in the upper 

 division of the Ocala Limestone. 



Species from the lower division of the Ocala Limestone include Textularia dibollensis Cushman and 

 Applin var. humblei Cushman and Applin, Eponides cocoaensis Cushman, Siphonina jacksonensis Cushman 

 and Applin, Cibicides mississippiensis (Cushman) yar. ocalanus Cushman, Camerina striatoreticulata 

 (L. Rutten), Operculina mariannensis Vaughan, Amphistegina pinarensis Cushman and Bermudez var. 

 cosdeni Applin and Jordan, Lepidocyclina Ocalana Cushman, and Asterocyclina georgiana (Cushman). 



The detailed faunal list in table 5 contains the more prominent foraminiferal species that have been 

 observed both in surface and subsurface occurrences of the upper Eocene deposits in Georgia. 



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