Usage:
Bar B Formation of Madera Group (NM*-notable exposures in Caballo Mountains area)
Geologic age:
Middle to Late Pennsylvanian (late Desmoinesian to Virgilian)*
Type section, locality, area and/or origin of name:
Type section (South Ridge section): in Caballo Mountains, east of Caballo Reservoir, [in northeastern corner of sec. 10 and northwestern corner sec. 11], T. 15 S., R. 4 W.; base of section at UTM Zone 13s, 291,508 m E., 3,656,226 m N., [Lat. 33 deg. 01 min. 28 sec. N., Long. 107 deg. 13 min. 56 sec. W., 5,600 ft elevation], top at UTM Zone 13s, 291,809 m E., 3,656,148 m N., [Lat. 33 deg. 01 min. 26 sec. N., Long. 107 deg. 13 min. 44 sec. W., 6,200 ft elevation, Palomas Gap 7.5-min quadrangle], Sierra Co., southwestern NM (Kelley and Silver, 1952; see also Lucas and others, 2012, New Mexico Geol. Soc. Gdbk., no. 63, p. 327-344).
Named from Bar B Draw [now spelled Barbee] east of Blue Mountain [Brushy Mountain] where, near head of draw, formation is widely exposed (Kelley and Silver, 1952).
AAPG geologic province:
Orogrande 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 ([ ]).