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National Geologic Map Database
Map showing publication footprint
  • Usage in publication:
    • Nakwasina Group*
  • Modifications:
    • Named
  • Dominant lithology:
    • Chert
    • Volcanics
    • Greenstone
  • AAPG geologic province:
    • Alaska Southeastern region
Publication:

Berg, H.C., and Hinckley, D.W., 1963, Reconnaissance geology of northern Baranof Island, Alaska, IN Contributions to general geology, 1961: U.S. Geological Survey Bulletin, 1141-O, p. O1-O24, (incl. geologic map, scale 1:125,000)


Summary:

Type area designated as shores of Nakwasina Passage and Nakwasina Sound (Baranof Island, southeastern AK), from which unit name is derived. Consists largely of metachert, volcanic rocks, and greenstone; marble, volcanic breccia, graywacke, argillite, phyllite, calcareous siltstone, schist, and hornfels occur locally. Group is probably many thousands of ft thick. Commonly separated from overlying rocks by faults; lower contact with schist and gneiss unit not observed. Considered to be Paleozoic(?) in age based on stratigraphic relations; no fossils found in unit.

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


Map showing publication footprint
  • Usage in publication:
    • Nakwasina Group*
  • Modifications:
    • Age modified
  • AAPG geologic province:
    • Alaska Southeastern region
Publication:

Loney, R.A., Berg, H.C., Pomeroy, J.S., and Brew, D.A., 1963, Reconnaissance geologic map of Chichagof Island and northwestern Baranof Island, Alaska: U.S. Geological Survey Miscellaneous Investigations Series Map, I-388, 1 sheet, scale 1:250,000


Summary:

[Overall] age is considered to be Permian(?) and Triassic(?) [based on regional correlation with Kelp Bay Group (part) and Katlian Group].

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


Map showing publication footprint
  • Usage in publication:
    • Nakwasina Group†
  • Modifications:
    • Abandoned
  • AAPG geologic province:
    • Alaska Southeastern region
Publication:

Loney, R.A., Brew, D.A., Muffler, L.J.P., and Pomeroy, J.S., 1975, Reconnaissance geology of Chichagof, Baranof, and Kruzof Islands, southeastern Alaska: U.S. Geological Survey Professional Paper, 792, 105 p., (incl. geologic map, scale 1:250,000)


Summary:

Unit is abandoned. Its strata are reassigned to Kelp Bay Group.

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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