84 
FLORIDA GEOLOGICAL SURVEY—I4TH ANNUAL REPORT 
Depth in feet. 
Light-colored, finely powdered limestone.I...:.:... 2240 
Slightly brownish limestone........ 2370 
White limestone ...... 2390 
Salt water.I..... 2405 
White limestone ... 2410 
Somewhat chalky, light colored limestone. 2590 
Dark limestone . JK., ..—. 2680 
Light-colored limestone ........M:....-.... 2700-3090 
The first samples obtained from this well were at a depth of 380 feet, 
and from that depth, according to Cushman (Twelfth Annual Report, 
page 89), to the bottom of the well is probably Lower Cretaceous. 
BROOKSVILLE AREA 
Somewhat detached from the Ocala Area just described is a smaller 
area lying to the west and including Citrus and Hernando Counties and 
a part of Pasco County. This area is topographically high and is sep¬ 
arated from the Ocala Area by the Withlacoochee Valley. The forma¬ 
tions at the surface include remnants of the Alum Bluff, Miocene, and 
occasional exposures of the underlying Eocene. Toward the southern 
part of the area, Oligocene limestones come into the section. 
The only deep well drilled in this area is one near Crystal River in 
Citrus County which reached a depth of 1,900 feet and obtained flowing 
salt water. No log of this well has been preserved. 
JACKSONVILLE AREA 
The underground conditions in the northeastern part of Florida are 
known from wells at Jacksonville and also at Fernandina and in the 
Lower St. Johns Valley. In this part of the state the Eocene formations 
that are at the surface in central Florida drop to a level of about 500 
feet below the surface. The formations drilled into at Jacksonville in¬ 
clude Miocene or later, Eocene and Cretaceous. 
Record of City Water IVell at Jacksonville* 
Depth in feet. 
Filled ground and sand... 0-15 
Sand with some clay... 15 - 33 
Sandy limestone, yellowish or light buff in color...... 33 - 37 
Light-colored clayey marl . 37 - 70 
Blue, sticky clay with black phosphatic pebbles... 70 -100 
*Fla. Geol. Surv., 5th Ann. Rept., pp. 177-178, 1913. 
