Usage:
Gem Hill Formation of Tropico Group (CA*)
Subunits:
Bobtail Quartz Latite Member (CA*).
Geologic age:
Tertiary
Oligocene(?)* to Miocene, middle*
Type section, locality, area and/or origin of name:
Gem Hill, 5.5 mi northwest of Rosamond, in S/2 sec. 25, SE/4 sec. 26, and NE/4 sec. 35, T. 10 N., R. 13 W., Rosamond 15-min quadrangle, Kern Co., CA (Dibblee, 1958).
AAPG geologic province:
Mojave 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 ([ ]).