Geologic units in Comal county, Texas

Glen Rose Limestone (Early Cretaceous) at surface, covers 51 % of this area

Glen Rose Limestone

Edwards Limestone (Early Cretaceous) at surface, covers 30 % of this area

Edwards Limestone

Pecan Gap Chalk (Late Cretaceous; Gulfian Series) at surface, covers 5 % of this area

Pecan Gap Chalk

Terrace deposits (Pleistocene and Holocene) at surface, covers 4 % of this area

Terrace deposits

Buda Limestone and Del Rio Clay, undivided (Late Cretaceous) at surface, covers 4 % of this area

Buda Limestone and Del Rio Clay, undivided; Eastern part of Trans-Pecos and High Plains and Western part of Trans-Pecos and North, central, and south Texas including Quaternary for all of west Texas.

Leona Formation (Pleistocene) at surface, covers 3 % of this area

Leona Formation

Hensell Sand (Early Cretaceous; Comanchean Series) at surface, covers 2 % of this area

Hensell Sand

Austin Chalk (Late Cretaceous; Gulfian Series) at surface, covers 1 % of this area

Austin Chalk

Eagle Ford Formation (Late Cretaceous) at surface, covers 0.4 % of this area

Eagle Ford Formation

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

Alluvium