No current usage.
(†Millsap Limestone (CO) replaced with Williams Canyon Limestone. See Williams Canyon.)
Early Mississippian
Named from Millsap Creek, Pikes Peak quadrangle, [Fremont 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 ([ ]).