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Map showing publication footprint
  • Usage in publication:
    • Sitkalidak Formation*
  • Modifications:
    • Named
  • Dominant lithology:
    • Sandstone
    • Siltstone
    • Conglomerate
  • AAPG geologic province:
    • Alaska Southwestern region
    • Kodiak province
Publication:

Moore, G.W., 1969, New formations on Kodiak and adjacent islands, Alaska, IN Cohee, G.V., and others, Changes in stratigraphic nomenclature by the U.S. Geological Survey, 1967: U.S. Geological Survey Bulletin, 1274-A, p. A27-A35.


Summary:

Named for Sitkalidak Island, AK. Type section designated along north coast and near east end of Sitkalidak Island from 3 to 7 km northwest of Cape Barnabas. Consists of uniform sequence of sandstone and siltstone graded beds with few conglomerate beds. Is about 3000 m thick. Overlies Ghost Rocks Formation (new) in fault contact; gradationally underlies Sitkinak Formation (new) or unconformably underlies Narrow Cape Formation (new). Fossil clam (new species of Vesicomyidae) and fossil crab (CALLIANASSA aff. C. PORTERENSIS) collected 300 m below top of unit indicate Oligocene age (F.S. MacNeil, written commun., 1963). Evidence from superposition suggest age of unit is Eocene and Oligocene.

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


Map showing publication footprint
  • Usage in publication:
    • Sitkalidak Formation*
  • Modifications:
    • Overview
  • AAPG geologic province:
    • Alaska Southwestern region
    • Kodiak province
Publication:

Nilsen, T.H., and Moore, G.W., 1979, Reconnaissance study of Upper Cretaceous to Miocene stratigraphic units and sedimentary facies, Kodiak and adjacent islands, Alaska, with a section on sedimentary petrography by G.R. Winkler: U.S. Geological Survey Professional Paper, 1093, 34 p.


Summary:

Detailed lithology, paleocurrent data, sedimentary facies, etc., included in report. Unit consists of middle- and outer-fan turbidites that locally include some basin-plain deposits.

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


Map showing publication footprint
  • Usage in publication:
    • Sitkalidak Formation*
  • Modifications:
    • Age modified
    • Biostratigraphic dating
  • AAPG geologic province:
    • Alaska Southwestern region
    • Kodiak province
Publication:

Clendenen, W.S., Sliter, W.V., and Byrne, Tim, 1992, Tectonic implications of the Albatross sedimentary sequence, a previously unrecognized unit on Sitkinak Island: U.S. Geological Survey Bulletin, 1999, p. 52-70.


Summary:

Sitkalidak Formation is Eocene age based on regional stratigraphic relations and foraminifers.

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


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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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