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National Geologic Map Database
Map showing publication footprint
  • Usage in publication:
    • Copper Lake Formation*
  • Modifications:
    • Named
  • Dominant lithology:
    • Conglomerate
    • Sandstone
    • Siltstone
  • AAPG geologic province:
    • Alaska Peninsula province
    • Alaska Southwestern region
Publication:

Detterman, R.L., and Reed, B.L., 1980, Stratigraphy, structure, and economic geology of the Iliamna quadrangle, Alaska, IN Geology of the Iliamna quadrangle, Alaska: U.S. Geological Survey Bulletin, 1368-B, p. B1-B86, (incl. geologic map, scale 1:250,000)


Summary:

Type section: composite of type sections of members: lower conglomerate member: east end of ridge 2.5 km S 45 deg E of outlet of Upper Copper Lake; sandstone and siltstone member: eastern slope of peak 2432, 1.6 km south of west end of Boot Lake; upper conglomerate member: ravine cutting eastern face of ridge between Fog and Kakhonak Lakes; all between Upper Copper Lake and Sid Larson Bay, southeast of Lake Iliamna, Iliamna quad, Alaska Peninsula, AK. Consists of gray conglomerate, sandstone, and siltstone. Lower conglomerate member is 91 m thick, sandstone and siltstone member, 503 m, and upper conglomerate member 975 m. Nonconformably overlies Middle Jurassic quartz diorite pluton or unconformably overlies Kakhonak Complex (new); unconformably underlies Tertiary volcanic rocks. Is Paleocene(?) and Eocene age.

Source: GNU records (USGS DDS-6; Menlo GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Copper Lake Formation*
  • Modifications:
    • Areal extent
  • AAPG geologic province:
    • Alaska Peninsula province
    • Alaska Southwestern region
Publication:

Detterman, R.L., Case, J.E., Miller, J.W., Wilson, F.H., and Yount, M.E., 1996, Stratigraphic framework of the Alaska Peninsula, IN Geologic studies on the Alaska Peninsula: U.S. Geological Survey Bulletin, 1969-A, 74 p.


Summary:

Copper Lake Formation. Unit geographically extended into Cape Douglas area (at expense of West Foreland Formation) based on lithology. Age here is Paleocene(?) and early Eocene.

Source: GNU records (USGS DDS-6; Menlo GNULEX).


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 ([ ]).

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