Caliche deposits
(Pleistocene and Holocene) at surface, covers 32 % of this area Caliche deposits
Fredericksburg Group
(Early Cretaceous; Comanchean Series) at surface, covers 3 % of this area Fredericksburg Group
Pond deposits
(Pleistocene) at surface, covers 2 % of this area Pond deposits
Alluvium
(Holocene) at surface, covers 2 % of this area Alluvium
Playa deposits
(Pleistocene and Holocene) at surface, covers 0.1 % of this area Playa deposits
Antlers Sand
(Early Cretaceous) at surface, covers < 0.1 % of this area Antlers Sand
Edwards Limestone
(Early Cretaceous) at surface, covers < 0.1 % of this area Edwards Limestone
Ogallala Formation
(Pliocene to Miocene) at surface, covers < 0.1 % of this area Ogallala Formation