/Yakima basalt subgroup [informal] of Columbia River Basalt Group (ID*,OR*,WA*)
[Yakima basalt subgroup considered informal and should not be capitalized. "Subgroup" not recognized as a formal stratigraphic rank term (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). Columbia River Basalt Group adopted by the ID, OR, and WA Geol. Surveys, and the USGS (rules suspended).]
"SUBGROUP" STATUS (alphabetical) --all in ID*,OR*,WA*: Grande Ronde Basalt, Saddle Mountains Basalt, Wanapum Basalt. ["Subgroup" not recognized as a formal stratigraphic rank term (CSN, 1933; ACSN, 1961; NACSN, 1983, 2005).]
late Tertiary (Miocene)*
Named from occurrence in Yakima area, eastern WA (Smith, 1901).
Eastern Columbia 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 ([ ]).