Hemphillian age*
Tertiary
Miocene, late
Pliocene, early
Name based on the Hemphill Member of Ogallala Group, Hemphill Co., Panhandle of TX (Wood and others, 1941).
North America
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 ([ ]).