PETROLEUM POSSIBILITIES OF FLORIDA 
109 
A well drilled for the city of Marianna in 1921 reached a depth of 
255 feet. This is the source of the public water supply and is a 10-inch 
well, with a head of 47 feet from the surface. No samples of the drill¬ 
ings were saved, but the following general log was obtained from the 
contracting engineers, the Albany Electric Company, Albany, Ga.: 
Log of New City Well, Marianna 
Surface soil and clays.... 1- 39 
Flint rock ......... 39- 41 
Hard limestone ___________ 41-186 
Cavity ......... 186-190 
Hard limestone ....... 190-212 
Flint rock ......... 212-226 
Cavity . 226-229 
Porous limestone . 229-250 
Flint rock . 250-253 
Cavity..........■... 253-255 
JEFFERSON COUNTY 
Jefferson County is in north Florida and extends from the Florida- 
Georgia state line south to the Gulf of Mexico. In the southern part 
of the county the Chattahoochee limestone is at the surface. In the 
northern part of the county this formation lies near the surface and is 
occasionally exposed in stream valleys, sinks and lake beds. Overlying 
the Chattahoochee formation in the northern part of the county is the 
Alum Bluff formation, together with red, sandy clays of undetermined 
age. 
Water wells have been drilled to a depth of 800 feet, but of these wells 
no record is available. 
LAFAYETTE COUNTY 
Lafayette County lies west of the Suwannee River and north of Dixie 
County. According to Matson, the Alum Bluff formation is present in 
this county. 1 The Chattahoochee limestone probably underlies the 
Alum Bluff. No deep wells are recorded in this county. 
LAKE COUNTY 
Lake County is in the lake region of central peninsular Florida. The 
surface materials over a large part of this county include red, sandy 
clays of undetermined age. At the eastern side of the county, on the St. 
X U. S. Geol. Surv., Water Supply Paper No. 319, p. 335, 1913. 
