Usage:
Bluff zone (informal) in Hermosa Formation (subsurface of AZ,NM,UT)
Informal. The rank or lithologic term should not be capitalized.
Geologic age:
Middle Pennsylvanian (Desmoinesian)
Type section, locality, area and/or origin of name:
Present in subsurface. Described from Bluff field discovery well, depth-interval 5,470 to 5,495 ft, Shell Bluff No. 3, in sec. 4, T. 40 S., R. 23 E., Paradox basin, San Juan Co., southeastern UT (Herman and Barkell, 1957).
AAPG geologic province:
Paradox basin
Black Mesa basin
San Juan 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 ([ ]).