Geologic units in Jeff Davis county, Texas

Older volcanic rocks of Davis and Barilla Mountains, including Sheep Pasture, Sleeping Lion, Frazier Canyon, Adobe Canyon, and Limpia formations, Gomez Tuff, Star Mountain Rhyolite, and Huelster Formation (Late Eocene) at surface, covers 33 % of this area

Older volcanic rocks of Davis and Barilla Mountains, including Sheep Pasture, Sleeping Lion, Frazier Canyon, Adobe Canyon, and Limpia formations, Gomez Tuff, Star Mountain Rhyolite, and Huelster Formation

Alluvium (Holocene) at surface, covers 24 % of this area

Alluvium

Younger volcanic rocks of Davis Mountains area including Brooks Mountain, Goat Canyon, Medley, Barrel Springs, Wild Cherry, Eppenaurer Ranch, Mount Locke, and Merrill Formations (Early Oligocene) at surface, covers 12 % of this area

Younger volcanic rocks of Davis Mountains area including Brooks Mountain, Goat Canyon, Medley, Barrel Springs, Wild Cherry, Eppenaurer Ranch, Mount Locke, and Merrill Formations

Alluvial fan deposits (Pleistocene and Holocene) at surface, covers 7 % of this area

Alluvial fan deposits

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

Land slide deposits

Older alluvial deposits (Pleistocene) at surface, covers 3 % of this area

Older alluvial deposits

Jones Basalt (Oligocene) at surface, covers 2 % of this area

Jones Basalt

Wiley Mountain caldera volcanic rocks (Eocene) at surface, covers 2 % of this area

Wiley Mountain caldera volcanic rocks

Ojinaga Formation (Late Cretaceous) at surface, covers 2 % of this area

Ojinaga Formation

Oligocene intrusive rocks (Oligocene) at surface, covers 1 % of this area

Oligocene intrusive rocks

Vieja Group, including Bracks Rhyolite, Chambers and Colmena Tuffs and Gill Breccia (Eocene to Oligocene) at surface, covers 1 % of this area

Vieja Group, including Bracks Rhyolite, Chambers and Colmena Tuffs and Gill Breccia

Quaternary-Tertiary deposits, undivided (Pliocene to Pleistocene) at surface, covers 1 % of this area

Quaternary-Tertiary deposits, undivided

Buda Limestone (Early Cretaceous) at surface, covers 0.9 % of this area

Buda Limestone; 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.

Boracho Limestone (Early Cretaceous) at surface, covers 0.7 % of this area

Boracho Limestone

Tarantula Gravel (Miocene) at surface, covers 0.7 % of this area

Tarantula Gravel

Duff Formation, Decie Member from Paisano caldera (Early Oligocene) at surface, covers 0.6 % of this area

Duff Formation, Decie Member from Paisano caldera

Bouquillas Formation (Late Cretaceous) at surface, covers 0.5 % of this area

Bouquillas Formation

Quaternary-Tertiary bolson deposits (Pliocene to Pleistocene) at surface, covers 0.5 % of this area

Quaternary-Tertiary bolson deposits

Gulfian rocks, undivided (Late Cretaceous) at surface, covers 0.4 % of this area

Gulfian rocks, undivided

Tertiary intrusive rocks, undivided (Tertiary) at surface, covers 0.4 % of this area

Tertiary intrusive rocks, undivided

Eocene intrusive rocks (Eocene) at surface, covers 0.3 % of this area

Eocene intrusive rocks

Cox Sandstone (Early Cretaceous) at surface, covers 0.2 % of this area

Cox Sandstone

Eagle Mountains caldera volcanic rocks (Oligocene) at surface, covers 0.2 % of this area

Eagle Mountains caldera volcanic rocks

Duff Formation (with Decie Member from Paisano caldera shown separately), Cottonwood Springs Basalt, Potato Hill Andesite, Sheep Canyon Basalt, Crossen Trachyte, and Pruett Formation, undivided (Late Eocene to Early Oligocene) at surface, covers 0.2 % of this area

Duff Formation (with Decie Member from Paisano caldera shown separaetly), Cottonwood Springs Basalt, Potato Hill Andesite, Sheep Canyon Basalt, Crossen Trachyte, and Pruett Formation, undivided

Finlay Limestone (Early Cretaceous; Comanchean; Albian Series) at surface, covers 0.1 % of this area

Finlay Limestone

Buda Limestone and Eagle Mountain Sandstone, undivided (Late Cretaceous) at surface, covers 0.1 % of this area

Buda Limestone and Eagle Mountain Sandstone, undivided

Washita Group (Early and Late Cretaceous; Comanchean Series) at surface, covers < 0.1 % of this area

Washita Group

Loma Plata Formation (Early Cretaceous; Comanchean Series) at surface, covers < 0.1 % of this area

Loma Plata Formation

Seven Rivers Formation (Permian; Guadalupe Series) at surface, covers < 0.1 % of this area

Seven Rivers Formation

Perdiz Conglomerate, Tascotal Formation, and tuffaceous sediments of Fresno Formation (Oligocene) at surface, covers < 0.1 % of this area

Perdiz Conglomerate, Tascotal Formation, and tuffaceous sediments of Fresno Formation

San Carlos Sandstone (Late Cretaceous) at surface, covers < 0.1 % of this area

San Carlos Sandstone

Bluff Mesa Formation (Early Cretaceous) at surface, covers < 0.1 % of this area

Bluff Mesa Formation; Western part of Trans-Pecos Texas.

Benevides Formation and Finlay Limestone, undivided (Early Cretaceous; Comanchean Series) at surface, covers < 0.1 % of this area

Benevides Formation and Finlay Limestone, undivided

Van Horn Mountains caldera volcanic rocks (Eocene) at surface, covers < 0.1 % of this area

Van Horn Mountains caldera volcanic rocks

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

Terrace deposits

Woods Hollow Shale, Fort Pena Formation, Alsate Shale, Marathon Limestone, and Dagger Flat Sandstone, undivided (Cambrian and Ordovician) at surface, covers < 0.1 % of this area

Woods Hollow Shale, Fort Pena Formation, Alsate Shale, Marathon Limestone, and Dagger Flat Sandstone, undivided

Victorio Peak Formation (Permian; Leonard Series) at surface, covers < 0.1 % of this area

Victorio Peak Formation