| State | Texas |
|---|---|
| Name | Devils Graveyard volcanic rocks |
| Geologic age | Eocene to Oligocene |
| Lithologic constituents | Major
Igneous > Volcanic > Mafic-volcanic > Basalt (Flow)
Igneous > Volcanic > Felsic-volcanic (Pyroclastic-air fall)
|
| Comments | Presidio and Brewster Cos., SW TX. Bandera Mesa member (upper member) basalt flow that underlies 32 m.y-old Mitchell Mesa Rhyolite. Bandera Mesa Mbr gave 33.2 and 33.7 +_ m.y. ages. Middle member is air-fall tuff dated at 42.8 m.y. Eocene and lower member tuffaceous sediment, air-fall tuff, and basalt flows dated 43.9 to 53.6 +_ m.y. Eocene. (Henry and others, 1986) |
| References | Bureau of Economic Geology, 1982, Fort Stockton Sheet, Geologic Atlas of Texas, University of Texas at Austin, scale 1:250,000.Bureau of Economic Geology, 1968, Van Horn-El Paso Sheet, Geologic Atlas of Texas: Bureau of Economic Geology, The University of Texas at Austin, scale 1:250,000.Bureau of Economic Geology, 1992, Geologic Map of Texas: University of Texas at Austin, Virgil E. Barnes, project supervisor, Hartmann, B.M. and Scranton, D.F., cartography, scale 1:500,000. |
| NGMDB product | |
| Counties | Brewster - Presidio |