Usage:
Purisima Formation (CA*)
Geologic age:
Pliocene, late* to Miocene, latest*
Type section, locality, area and/or origin of name:
Named from exposures near Purisima and along Purisima Creek, Santa Cruz Mountains, San Mateo Co., [greater San Francisco Bay area, Half Moon Bay quadrangle], western CA (Haehl and Arnold, 1904; see also Powell and others, 2007).
Reference section: sea cliff section from Santa Cruz eastward to Rio del Mar, Santa Cruz Co., central California Coast Ranges, greater San Francisco Bay area, western CA (Powell and others, 2007).
AAPG geologic province:
Santa Cruz 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 ([ ]).