GEOLOGY BETWEEN APALACHICOLA AND OCKLOCKNEE RIVERS. 55 
The Choctawhatchee formation which rests uncon formably upon 
the Alum Bluff formation clips very gradually to the south, prob- 
ably not in excess of 2 1-3 feet per mile. The red sands and clays 
lying above the Choctawhatchee formation conform so far as can 
be determined essentially to the structure, of the underlying forma- 
tion dipping gradually in passing to the coast. To the north these 
red sands extend beyond the limits of the Choctawhatchee forma- 
tion and rest directly upon the sands of the Alum Bluff formation. 
Fig. 5. Exposure of the Chattahoochee formation in railway cut near 
River Junction. 
