Qal
Alluvium
Holocene and late Pleistocene
Ql
Leona Formation
Pleistocene
Kau
Austin Chalk
Upper Cretaceous, Santonian-Coniacian
Qt
Terrace alluvium
late Pleistocene
Kef
Eagle Ford Formation
Upper Cretaceous, Turonian
Ki
Igneous intrusive rocks
Late Cretaceous
Kbu
Buda Limestone
Upper Cretaceous, Turonian-Cenomanian
Qc
Colluvium
af
Artificial fill
modern
Kdr
Del Rio Formation
Upper Cretaceous, Cenomanian
Ksp
Salmon Peak Limestone
Lower Cretaceous, upper Albian
Qls
Landslide Deposit
Kmm
McKnight Formation, Middle member
Lower Cretaceous Albian
Kmu
McKnight Formation, Upper member
Qaf
Fan alluvium
Kml
McKnight Formation, Lower member
Kwn
West Nueces Formation
Lower Cretaceous, Albian
Km
McKnight Formation, undivided
Kgr
Glen Rose Formation
Lower Cretaceous, lower Albian
Kdvr
Devils River Limestone