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National Geologic Map Database

Geologic Unit: Astoria

Usage:

Astoria Formation (OR*,WA*)
Astoria Shale (OR,WA)


Subunits:

(ascending) [not adopted by USGS]: Angora Peak Member (OR,WA), Silver Point Member [not recorded in GNU records (USGS DDS-6)], Newport sandstone member (informal), and Big Creek sandstone member (informal).


Geologic age:

late Tertiary (early to middle Miocene)*


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

Notable exposures in city of Astoria, OR, on south side of Coumbia River near its mouth. Formation has been folded into a syncline whose axis trends northwest through city of Astoria (Howe, 1926; Moore, 1963). [Exposures now inaccessible as result of urban development.]
"Best" stratigraphic section: ridge between Chehalis River and North River, [in T. 16 and 17 [N.], R. 7 W.], southwestern WA (Etherington, 1931).
Reference section: "Clemons section" (Etherington, 1931).


AAPG geologic province:

Oregon-Washington Coast Ranges 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 ([ ]).