Umpqua Formation (CA,OR*)
Umpqua Group (OR)
GROUP STATUS: Roseburg, Lookingglass, and Flournoy Formations [not adopted by USGS].
FORMATION STATUS (ascending): Bushnell Rock, Tenmile, White Tail Ridge, and Camas Valley Members [not adopted by USGS].
Type section: occurs along north Umpqua River, about 17 mi northeast of Roseburg, Douglas Co., OR (Weaver and others, 1944).
Oregon-Washington Coast Ranges province*
Klamath Mountains province*
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
Asterisk (*) indicates usage by the U.S. Geological Survey. Other usages by state geological surveys.
"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 does not conform with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). This may be explained within brackets ([ ]).