Geologic units in Floyd county, Texas

Blackwater Draw Formation (Pleistocene) at surface, covers 85 % of this area

Blackwater Draw Formation

Ogallala Formation (Pliocene to Miocene) at surface, covers 6 % of this area

Ogallala Formation

Dockum Group, undivided (Late Triassic) at surface, covers 4 % of this area

Dockum Group

Playa deposits (Pleistocene and Holocene) at surface, covers 2 % of this area

Playa deposits

Quartermaster Formation (Permian; Guadalupe Series) at surface, covers 2 % of this area

Quartermaster Formation; North and central Texas including panhandle.

Lingos Formation (Middle (?) Pleistocene to Recent) at surface, covers 0.9 % of this area

Lingos Formation

Alluvium (Holocene) at surface, covers 0.1 % of this area

Alluvium

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

Sand dune deposits

Quaternary deposit, undivided (Quaternary) at surface, covers < 0.1 % of this area

Quaternary deposit, undivided

Edwards Limestone (Early Cretaceous) at surface, covers < 0.1 % of this area

Edwards Limestone

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

Sand sheet deposits