Usage:
No current usage
(†Derry Series of Pennsylvanian System (NM) considered obsolete.)
Geologic age:
Middle Pennsylvanian
(Atokan)
Type section, locality, area and/or origin of name:
Type section: measured on west-facing slope of hill about 0.75 mi east of center of village of Derry, near center sec. 32, T. 17 S., R. 4 W., Sierra Co., southwestern NM. Named from Derry (Thompson, 1942).
AAPG geologic province:
San Juan basin
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 ([ ]).