Usage:
U-Bar Formation of Bisbee Group (AZ?,NM)
U-Bar Formation (NM*)
Geologic age:
Early Cretaceous*
Type section, locality, area and/or origin of name:
Type section (composite): lower part in NE/4 sec. 10, T. 32 S., R. 15 W.; middle part in NW/4 sec. 32, T. 31 S., R. 15 W.; and upper part in NE/4 sec. 31, T. 31 S., R. 15 W., Hidalgo Co., NM. Named from U-Bar Ridge (Zeller, 1965).
Reference section: lower part on Little Hat Top, in sec. 19, T. 32 S., R. 14 W.; and oyster limestone and limestone shale members on Pierce Tank, in secs. 29 and 30, T. 32 S., R. 14 W., Hidalgo Co., NM (Zeller, 1965).
AAPG geologic province:
Pedregosa basin*
Basin-and-Range province*
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 ([ ]).