Tuscaloosa Group; Gordo Formation

Massive beds of cross-bedded sand, gravelly sand, and lenticular beds of locally carbonaceous partly mottled moderate-red and pale-red-purple clay; lower part is predominantly a gravelly sand consisting chiefly of chert and quartz pebbles. Not mapped east of the Tallapooza River.
State Alabama
Name Tuscaloosa Group; Gordo Formation
Geologic age Cretaceous
Lithologic constituents
Major
Unconsolidated > Fine-detrital > Clay (Bed)lenticular beds of locally carbonaceous partly mottled moderate-red and pale-red-purple clay
Unconsolidated > Coarse-detrital > Sand (Bed)Massive beds of cross-bedded sand, gravelly sand.
Minor
Unconsolidated > Coarse-detrital > Gravel (Bed)lower part is predominantly a gravelly sand consisting cheifly of chert and quartz pebbles.
Incidental
Sedimentary > Chemical > Chert (Bed)lower part is predominantly a gravelly sand consisting cheifly of chert and quartz pebbles.
References

Szabo, M.W., Osborne, E.W., Copeland, C.W. Jr., and Neathery, T.L., 1988, Geologic Map of Alabama, Geological Survey of Alabama Special Map 220, scale 1:250,000.

NGMDB product
Counties Autauga - Bibb - Chilton - Colbert - Dallas - Elmore - Fayette - Franklin - Greene - Hale - Lamar - Lauderdale - Marion - Perry - Pickens - Tuscaloosa