94 FLORIDA GEOLOGICAL SURVEY ELEVENTH ANNUAL REPORT. 
2 1-3 feet per mile. From the exposures on the Chipola River 
only an approximate estimate of the rate of dip of the formation 
can be given. On Four Mile Creek near Clarksville the base of 
this formation lies 13 feet above water level in the river, while 
4 or 5 miles below Clarksville at Darling Slide and Abe’s Spring, 
the base of the formation is somewhat below water level, indicat- 
ing a dip to the south of 3 feet or more per mile. 
In order to get further data on the position of this formation, 
levels were made at one place west of the Choctawhatchee River.* 
The Choctawhatchee marl on John Anderson’s farm about 1 
mile south of Red Bay in W alton County lies 102 feet above 
water level in the river, date of June 5, 1918. The base of the 
formation lies from 10 to 30 or more feet below the exposure from: 
which the levels were taken, or between 70 and 90 feet above water 
level in the river. On the following day the water level in the 
river at the Louisville & Nashville Railway crossing was found 
from known levels on the railway to be 33.3 feet above sea. From 
this crossing to the Bay at the mouth of the river, following the 
course of the stream;, is probably between 30 and 35 miles. Hence 
the fall of the river in this part of its course is close to one foot 
per mile. From the Louisville & Nashville Railway crossing to 
Red Bay, following the general course of the river, is about 13 
miles. Hence water level in the river at Red Bay is close to 20 
feet above sea, and the level of the base of the Choctawhatchee 
formation at this place accordingly is probably between 90 and 120 
feet above sea. These measurements indicate that in passing from 
east to west, or slightly north of west, the Choctawhatchee for- 
mation lies essentially at a uniforn level, the dip being south or 
slightly west of south. 
MIOCENE-PLIOCENE?. 
In this area as in the country to the east of the Apalachicola 
River, depisits of sand, pebble and clay lie above the Choctawhat- 
chee formation. On Four Mile Creek near Clarksville about 65 
feet of sandy material, mostly covered by the sloping hill, overlies 
the Choctawhatchee formation. At Round Lake and in some other 
* Levels made by H. Gunter, June 5, 1918. 
