REVIEW OF THE GEOLOGY OF FLORIDA 121 
STRUCTURE OF PENINSULAR FLORIDA. 
For some years the Florida Geological Survey has been col¬ 
lecting well logs and well cuttings with special view to determin¬ 
ing so far as practicable the structural conditions underlying pen¬ 
insular Florida. This work has progressed slowly, although some 
data have now accumulated that have a very important bearing on 
this problem. Early in 1918 cuttings containing numerous fo- 
raminifera from a deep well then recently completed in Sumter 
County were sent to Dr. T. W. Vaughan of the U. S. Geological 
Survey, by whom they were referred to Dr. J. A. Cushman. Dr. 
Cushman’s identification of the foraminifera of these samples led 
to the very unexpected result that they indicated the presence of 
Comanchean (Lower Cretaceous) formations. Subsequently Dr. 
Cushman undertook the identification for the Survey, of the fo¬ 
raminifera in the cutting from about fifteen wells in Florida. This 
work was completed early in 1919 and the report on the well sam¬ 
ples is published herewith. In addition there are a number of other 
wells that from logs or partial sets of samples give approximate 
data of service in this study. 
SKETCH MAP OF STRUCTURAL CONDITIONS IN FLORIDA. 
Upon the basis of all data available at this time there has been 
constructed a sketch map which represents approximately what is 
known of structural conditions in the peninsular section of Flor¬ 
ida. On this map there is indicated an area in the west central 
part of the peninsula, marked “A”, in which the top of the Eocene 
limestones lie at or above sea level. The data for placing the east¬ 
ern margin of this area are very limited and the boundaries are 
necessarily very roughly approximated. In the lake region of 
Clay County in particular it is possible that the Eocene limestones 
may lie closer to the surface than is here indicated. The following 
description of samples from two wells at Apopka within this area 
has not been published heretofore. 
Record of the City well at Apopka, Florida. Drilled February 1915. Mr. 
Starbird, driller. Samples submitted by Mr. S. G. Hull. Casing rested at 
117 feet. 
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