No current usage.
(†Alnwick Lake Beds (CO) replaced with Tallahassee Creek Conglomerate. See Tallahassee Creek.)
late Tertiary (late Miocene or Pliocene)
Notable exposures in valley of Oil Creek about Alnwick, Pikes Peak region, [Teller Co.], eastern CO (Cross, 1894).
Denver 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 ([ ]).