Pinkerton Trail Formation of Hermosa Group (AZ*,CO*,NM*,UT*)
Pinkerton Trail Limestone of Hermosa Group (CO,UT)
Middle Pennsylvanian (Atokan to Desmoinesian)*
On Pinkerton Trail near Denver and Rio Grande RR tracks, about 12 mi north of Durango, La Plata Co., CO. Named from Pinkerton Trail (Wengerd and Strickland, 1954).
Reference section (subsurface): Shell No. 1 Bluff well, in sec. 32, T. 39 S., R. 23 E., San Juan Co., UT (Baars and others, 1967).
San Juan basin
Black Mesa basin*
Paradox 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 ([ ]).