Usage:
Del Valle Formation (CA)
Geologic age:
Late Cretaceous
Type section, locality, area and/or origin of name:
Arroyo del Valle-Rocky Ridge area of northeastern La Costa Valley quadrangle, Alameda Co., northern CA, where it covers approximately 4 sq mi; extends into Tesla quadrangle (Hall, 1958).
AAPG geologic province:
Northern Coast Range province
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 ([ ]).