Geologic units in Deaf Smith county, Texas

Blackwater Draw Formation (Pleistocene) at surface, covers 84 % of this area

Blackwater Draw Formation

Ogallala Formation (Pliocene to Miocene) at surface, covers 10 % of this area

Ogallala Formation

Chinle Formation (Late Triassic) at surface, covers 4 % of this area

Chinle Formation

Playa deposits (Pleistocene and Holocene) at surface, covers 0.9 % of this area

Playa deposits

Unnamed Pliocene deposits (Pliocene) at surface, covers 0.4 % of this area

Unnamed Pliocene deposits

Alluvium (Holocene) at surface, covers 0.3 % of this area

Alluvium

Dockum Group, undivided (Late Triassic) at surface, covers 0.2 % of this area

Dockum Group

Quaternary deposit, undivided (Quaternary) at surface, covers 0.2 % of this area

Quaternary deposit, undivided

Sand dune deposits (Holocene) at surface, covers 0.2 % of this area

Sand dune deposits

Caliche deposits (Pleistocene and Holocene) at surface, covers < 0.1 % of this area

Caliche deposits

Ogallala Formation (Lower Pliocene to middle Miocene) at surface, covers < 0.1 % of this area

Alluvial and eolian deposits, and petrocalcic soils of the southern High Plains. Locally includes Qoa.

Upper Chinle Group, Garita Creek through Redonda Formations, undivided (Upper Triassic) at surface, covers < 0.1 % of this area

Upper Chinle Group, Garita Creek through Redonda Formations, undivided

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.