- Usage in publication:
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- Eagle Creek Formation*
- Modifications:
-
- Named
- Biostratigraphic dating
- Dominant lithology:
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- Limestone
- Argillite
- AAPG geologic province:
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- Alaska Southern region
Summary:
Named as unit in Mankomen Group (newly defined). Type locality designated as west side of Eagle Creek valley, secs.22-23,27,34 T15N R5E, Mt. Hayes A-1 (1:63,360) quad, south-central AK. Divided into four informal members (ascending): lower limestone, lower argillite, upper limestone, and upper argillite members. Measured sections with fossil assemblages included in report. Total thickness is 2938 ft. Conformably overlies Slana Spur Formation (new) (Mankomen Group). Conformably underlies Nikolai Greenstone or unnamed chert and limestone. Is Early Permian (Sakmarian and Artinskian) age based on brachiopods and fusulinids.
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 ([ ]).