Geologic units in Foard county, Texas

Blaine Formation (Permian; Guadalupe Series) at surface, covers 35 % of this area

Blaine Formation

Clear Fork Group (Permian; Leonard Series) at surface, covers 25 % of this area

Clear Fork Group

San Angelo Formation (Permian; Guadalupe Series) at surface, covers 11 % of this area

San Angelo Formation

Quaternary deposit, undivided (Quaternary) at surface, covers 10 % of this area

Quaternary deposit, undivided

Seymour Formation (Middle Pleistocene; Irvingtonian) at surface, covers 10 % of this area

Seymour Formation

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

Sand sheet deposits

Alluvium (Holocene) at surface, covers 3 % of this area

Alluvium

Dune sand sheet deposits (Holocene) at surface, covers 2 % of this area

Dune sand sheet deposits

Terrace deposits (Pleistocene and Holocene) at surface, covers 1 % of this area

Terrace deposits

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

Playa deposits