Fig. 3. Sketch map to indicate general structural conditions in Florida. A. 
Belt of country in which the Eocene formations, when present, lie above sea 
level, mostly from sea level to as much as about 100 feet above. B. Eocene for¬ 
mations'below sea level; for the most part between o and 200 feet below. 
Doubtful territory for both belts A and B is indicated by a question mark.. 
C. Eocene formations probably more than 200 feet below sea level, varying: 
from 200 feet to a maximum, so far as known, of about 1000 feet in the 
southern part of the peninsula. Figures entered in the map record approxi¬ 
mate depth to the top surface of the Eocene, usually the Ocala formation. 
The margins of the Floridian land mass are approximately coincident with 
the 100 fathom contour, the location of which is indicated on the map. The 
axis of the land mass is approximately indicated by the line a-a'. 
