Geologic units in Hartley county, Texas

Sand sheet deposits (Holocene) at surface, covers 33 % of this area

Sand sheet deposits

Blackwater Draw Formation (Pleistocene) at surface, covers 30 % of this area

Blackwater Draw Formation

Ogallala Formation (Pliocene to Miocene) at surface, covers 27 % of this area

Ogallala Formation

Tecovas Formation (Late Triassic) at surface, covers 3 % of this area

Tecovas Formation

Dune sand sheet deposits (Holocene) at surface, covers 3 % of this area

Dune sand sheet deposits

Rita Blanca Formation (Pliocene) at surface, covers 2 % of this area

Rita Blanca Formation

Alluvium (Holocene) at surface, covers 1 % of this area

Alluvium

Caliche deposits (Pleistocene and Holocene) at surface, covers 0.5 % of this area

Caliche deposits

Trujillo Formation (Late Triassic) at surface, covers 0.3 % of this area

Trujillo Formation

Playa deposits (Pleistocene and Holocene) at surface, covers 0.3 % of this area

Playa deposits

Sand dune deposits (Holocene) at surface, covers < 0.1 % of this area

Sand dune deposits

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

Terrace deposits

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

Eolian deposits.