Midway Group; Clayton Formation

White to yellowsih-gray argillaceous limestone occurs in the upper part (McBryde Limestone Member): the lower part is medium-gray fossiliferous calcareous silt, glauconitic sand and thin beds of sandy limestone and calcareous sandstone (Pine Barren Member). At the base of the formation in southeast AL is a gravelly medium to coarse sand containing clay pebbles. The formation thins west of Wilcox County and westward from Thomaston in eastern Marengo County is mapped with the Porters Creek Formation. The formation is generally deeply weathered and fresh exposures are rare. In western areas exposures consist of weathered white to yellowish-gray argillaceous, fossiliferous sandy limestone, ferruginous sand, and fossiliferous sandstone. In eastern areas exposures consist of residual accumulations of chert boulders, moderate-reddish-orange sand, and clay containing masses and thin layers of iron minerals (limonite-goethite).
State Alabama
Name Midway Group; Clayton Formation
Geologic age Paleocene
Lithologic constituents
Sedimentary > Carbonate > Limestone (Bed)White to yellowsih-gray argillaceous limestone, yellowish-gray argillaceous, fossiliferous sandy limestone.
Unconsolidated > Fine-detrital > Silt (Bed)the lower part is medium-gray fossiliferous calcareous silt
Unconsolidated > Fine-detrital > Clay
Sedimentary > Clastic > Sandstone (Bed)calcareous sandstone (Pine Barren Member), fossiliferous sandstone.
Unconsolidated > Coarse-detrital > Sand (Bed)glauconitic sand, ferruginous sand
Sedimentary > Chemical > Chert

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 Barbour - Bullock - Butler - Coffee - Crenshaw - Dallas - Henry - Lowndes - Marengo - Pike - Wilcox