| State | Texas |
|---|---|
| Name | Black Peaks Member of Tornillo Formation |
| Geologic age | Paleocene |
| Lithologic constituents | Major
Sedimentary > Clastic > Sandstone (Bed)
Sedimentary > Clastic > Mudstone > Claystone (Bed)
|
| Comments | Sandstone and clay; sandstone at base, conglomeratic, crossbedded, gray to grayish white, some cannonball concretions split into platy layers; clay, mottled gray and deep dark-red; vertebrate fossils common; thickness ranges from 284 to 866 ft, crops out in northern part of Big Bend NP. |
| References | Bureau of Economic Geology, 1979, Emory Peak--Presidio Sheet, Geologic Atlas of Texas, University of Texas at Austin.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 |