/Dry Creek sandstone member [informal] of Ione Formation (CA*)
[Preoccupied. Name previously applied to Dry Creek Shale by Peale (1893) in MT.] Considered informal by the USGS. For informal usage, the rank or lithologic term should not be capitalized.
Tertiary
Eocene, middle
Named from beds on tributary of Dry Creek, Chico quadrangle, north-central CA (Allen, 1929).
Sacramento 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 ([ ]).