Geologic units in Cochran county, Texas

Blackwater Draw Formation (Pleistocene) at surface, covers 75 % of this area

Blackwater Draw Formation

Sand deposits, undivided (Holocene) at surface, covers 16 % of this area

Sand deposits, undivided

Sand sheet deposits (Holocene) at surface, covers 5 % of this area

Sand sheet deposits

Ogallala Formation (Pliocene to Miocene) at surface, covers 3 % of this area

Ogallala Formation

Sand dune deposits (Holocene) at surface, covers 0.4 % of this area

Sand dune deposits

Pond deposits (Pleistocene) at surface, covers 0.3 % of this area

Pond deposits

Tahoka Formation (Pleistocene; Wisconsinan) at surface, covers 0.1 % of this area

Tahoka Formation

Eolian deposits (Holocene to middle Pleistocene) at surface, covers < 0.1 % of this area

Eolian deposits.

Older alluvial deposits of upland plains and piedmont areas, and calcic soils and eolian cover sediments of High Plains region (Middle to lower Pleistocene) at surface, covers < 0.1 % of this area

Includes scattered lacustrine, playa, and alluvial deposits of the Tahoka, Double Tanks, Tule, Blanco, Blackwater Draw, and Gatuna Formations, the latter of which may be Pliocene at base; outcrops, however, are basically of Quaternary deposits.