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National Geologic Map Database

Geologic Unit: Dalles

Usage:

Dalles Formation (OR*,WA*)
Dalles Group (OR)


Subunits:

GROUP STATUS (alphabetical) --all in OR: Alkali Canyon Formation, Chenoweth Formation, Deschutes Formation, McKay Formation, Tygh Valley Formation.


Geologic age:

late Tertiary (late Miocene)*


Type section, locality, area and/or origin of name:

[Notable exposures along Columbia River, near The Dalles, Wasco Co., western OR.]


AAPG geologic province:

Columbia basin*
Cascades province*
Blue Mountains province*
Great Basin 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 ([ ]).