Selma Group; Prairie Bluff Chalk (ALKpb;1)

Prairie Bluff Chalk - (Selma Group), Very light-gray to light-bluish-gray firm sandy, fossiliferous brittle chalk and grayish-black silty sandy calcareous glauconitic, fossiliferous clay; semi-indurated beds of sandy, clayey limestone are present in some exposures. Abscent locally in parts of Marengo, Dallas and Wilcox Counties where overlapped by the Clayton Formation or eroded. The Prairie Bluff thins eastward from southwestern Lowndes County to northern Pike County where it interfingers with the Providence Sand.

State	Alabama
Name	Selma Group; Prairie Bluff Chalk
Geologic age	Upper Cretaceous
Original map label	Kpb
Primary rock type	carbonate
Secondary rock type	clay or mud
Other rock types	sand; silt; limestone
Lithologic constituents	Major Unconsolidated > Fine-detrital > Claygrayish-black silty sandy calcareous glauconitic, fossiliferous clay. Sedimentary > Carbonate > Limestone > ChalkVery light-gray to light-bluish-gray firm sandy, fossiliferous brittle chalk Minor Sedimentary > Carbonate > Limestone Unconsolidated > Fine-detrital > Silt Unconsolidated > Coarse-detrital > Sand
Map references	Szabo, M. W., Osborne, E. W., Copeland, C. W. Jr., Neathery; T. L., 1988, Geologic Map of Alabama, Geological Survey of Alabama Special Map 220, scale 1:250,000. [http://www.ogb.state.al.us/ogb/ogb_gisdata/algeomap.zip]
Unit references	Szabo, M. W., Osborne, E. W., Copeland, C. W. Jr., Neathery; T. L., 1988, Geologic Map of Alabama, Geological Survey of Alabama Special Map 220, scale 1:250,000. [http://www.ogb.state.al.us/ogb/ogb_gisdata/algeomap.zip]
Geographic coverage	Crenshaw - Dallas - Lowndes - Montgomery - Pike - Sumter - Wilcox