Usage:
Ash Hollow Formation of Ogallala Group (NE,SD)
Subunits:
(alphabetical): Cap Rock Member (NE,SD), Feldt Ranch Beds (NE), Merrit Dam Member (NE).
Geologic age:
late Tertiary (Miocene; Clarendonian to possibly late? Hemphillian NALMA)
Type section, locality, area and/or origin of name:
Type section: exposures in Ash Hollow Canyon, [in Ash Hollow State Historical Park], southeast of Lewellen, Garden Co., western NE (Engelmann, 1876; Lugn, 1938, 1939).
AAPG geologic province:
Chadron arch
Denver basin
Powder River basin
Salina basin
Sioux uplift
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 ([ ]).