describe the location of the geologic section, the county name and the Georgia Geological Survey number 

 of the well are given: e.g., Atkinson 107. Under this number are filed in the sample library maintained by 

 the Georgia Department of Mines, Mining and Geology, the cuttings of the wells which are available 

 for further study by geologists and paleontologists. The numbers also are the same as those used in the 

 well-log report by Herrick (1961). 



One paper which the authors have used extensively is that by Paul and Esther Applin (1944), on the' 

 "Regional subsurface stratigraphy and structure of Florida and southern Georgia." Because the Ap- 

 plins' paper has been so remarkably useful, the authors have chosen to model this present paper more 

 or less along similar lines. 



Mapping Methods 



The data presented are separated by horizontal distances measured in miles but the vertical measure- 

 ments are in feet. Furthermore, errors in sampling and in interpretation of the samples can have too 

 much influence in locating contour lines if the data are contoured mechanically. Therefore, the maps 

 were prepared with the contours drawn to show the major structure thereby eliminating many of the minor 

 features that strict mechanical contouring would show. At this stage in the investigation of the subsurface, 

 the major features are not yet fully understood so adding minor ones would tend to obscure rather than 

 aid interpretation. 



The contoured maps have been superimposed to try and make the maps consistent one with another. 

 Because of the wide spacing of many of the wells and lack of wells elsewhere the maps can be drawn with 

 remarkably differing interpretation. Therefore, these maps are presented as the current interpretation 

 of the authors and with the realization that they will, need to be modified considerably as new data become 

 available and as other interpretations are found to be more valid. 



In order to make the maps more readily comparable, the contour interval on most of the maps is 

 100 feet. The tops of the lower Eocene down to the Tuscaloosa (of Late Cretaceous age) are contoured 

 at an interval of 200 feet. The top of the Lower Cretaceous(?) and the pre-Cretaceous were contoured 

 at 500-foot intervals. The thickness-distribution map for the Lower Cretaceous(?) was prepared with 

 a contour interval of 400 feet. 



Because of the many maps included in this study, the symbols used are listed and described in table 

 3 rather than having essentially the same explanation repeated on each map. 



