Usage:
Allen Ridge Formation of Mesaverde Group (WY*)
Geologic age:
Late Cretaceous (Campanian)*
Type section, locality, area and/or origin of name:
Principal reference section: along north and south sides of Pine Tree Gulch [now Pine Draw], in S/2 NE/4 sec. 19, T. 23 N., R. 79 W., [about 7.5 mi northwest of Medicine Bow, approx. Lat. 41 deg. 57 min. 10 sec. N., Long. 106 deg. 19 min. 50 sec. W., Como East 7.5-min quadrangle], Carbon Co., south-central WY [authors unable to recover Bergstrom's composite type section] (Gill and others, 1970).
Type section (composite): from sec. 9, T. 22 N., R. 79 W., and sec. 18, T. 23 N., R. 79 W., [Como East 7.5-min quadrangle], Carbon Co., south-central WY (Bergstrom, 1959).
Apparently named from ridge adjacent to Allen Station [now abandoned] on the Union Pacific RR [in S/2 SW/4 sec. 10, T. 22 N., R. 79 W., approx. Lat. 41 deg. 53 min. 13 sec. N., Long. 106 deg. 16 min. 55 sec. W., Saddleback Hills 15-min quadrangle (1914; 1921 ed.)], Carbon Co., south-central WY (Bergstrom, 1959; see also Gill and others, 1970).
AAPG geologic province:
Green River 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 ([ ]).