Usage:
Mule Ear Spring Tuff of Chisos Group (TX-local)
Recognized in southwestern TX, notably Trans-Pecos area, Big Bend National Park, and Big Bend Ranch State Park.
Geologic age:
early Tertiary (Oligocene)
Type section, locality, area and/or origin of name:
Named from Mule Ear Spring, 1.5 mi northwest of Mule Ear Peaks, Big Bend National Park, Brewster Co., TX. Member crops out in escarpment northwest of Contrabando Dome and along west wall of Fresno Canyon. East of Fresno Creek, it caps prominent hill northwest of Fresno mine and crops out in hills southwest and northwest of Chimney Rock in Terlingua quadrangle. Extends into Mexico (Maxwell and Hazzard, 1967).
AAPG geologic province:
Permian basin
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
Asterisk (*) indicates published by U.S. Geological Survey authors.
"No current usage" (†) implies that a name has been abandoned or has fallen into disuse. Former usage and, if known, replacement name given in parentheses ( ).
Slash (/) indicates name conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).