100 
FLORIDA GEOLOGICAL SURVEY-I4TH ANNUAL REPORT 
Depth from surface. 
Calcareous, fine, green sand, some clay.. 1270 
Medium fine, glauconitic and calcareous sand... 1280 
Coarse, calcareous sand and glauconite.... 1290 
Gray, medium fine, calcareous sand, with some glauconite. 1300-1320 
CHARLOTTE COUNTY 
Charlotte County on the Gulf coast of southern Florida includes pre¬ 
vailingly level land of but moderate elevation. In the western part of 
the county are found exposures of Pliocene shell marls, and these shell 
beds probably underlie much of the county. No wells of great depth 
are recorded, although artesian water is obtained from about 200 to 
about 500 feet. 
CITRUS COUNTY 
Citrus County is in the Brooksville geological area and lies be¬ 
tween the Withlacoochee River and the Gulf of Mexico. The surface 
formations in this county are chiefly Eocene, with probably some Pleisto¬ 
cene in the river valleys and near the coast. Remnants are present of 
the Alum Bluff Miocene, as well as local deposits of a phosphate-bearing 
formation derived from the Alum Bluff formation. One well has been 
drilled near Crystal River, said to have reached to a depth of 1,900 feet. 
This well, of which no log is available, obtained flowing salt water. 
clay county 
Clay County is located in northeast Florida on the west side of the 
St. Johns River. From the St. Johns River the elevation rises rapidly 
and the western margin of the county extends to the highlands crossed 
by Trail Ridge. On Black Creek, in this county, are seen exposures of 
Miocene phosphatic marls. From available well records it appears that 
the Eocene limestones are reached in the eastern part of this county at 
a depth of about 400 feet. Flowing artesian water from Eocene (or 
older?) formations is obtained at Green Cove Springs, Doctor’s Inlet 
and elsewhere in this county. 
COLUMBIA COUNTY 
In the southern part of Columbia County the Ocala formation (Eo¬ 
cene) is found at the surface. In the central and northern parts of the 
county this formation disappears below the surface and the Alum Bluff 
