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Map showing publication footprint
  • Usage in publication:
    • Four Mile Dam formation*
  • Modifications:
    • Original reference
  • Dominant lithology:
    • Limestone
  • AAPG geologic province:
    • Michigan basin
Publication:

Cooper, G.A., and Warthin, A.S., Jr., 1941, New Middle Devonian names [of geologic formations]: Washington Academy of Sciences Journal, v. 31, no. 6, p. 250-260.


Summary:

Pg. 260. Four Mile Dam formation. Fossiliferous limestone, which at its type section is a part of a reef of uncertain thickness overlain unconformably by Norway Point formation. Age is Middle Devonian.
Type section: at Four Mile Dam on Thunder Bay River, Alpena Co., northeastern MI.

Source: US geologic names lexicon (USGS Bull. 1200, p. 1408).


Map showing publication footprint
  • Usage in publication:
    • Four Mile Dam formation*
  • Modifications:
    • Revised
  • AAPG geologic province:
    • Michigan basin
Publication:

Warthin, A.S., Jr., and Cooper, G.A., 1943, Traverse rocks of Thunder Bay region, Michigan: American Association of Petroleum Geologists Bulletin, v. 27, no. 5, p. 571-595. [Available online, with subscription, from AAPG archives: http://www.aapg.org/datasystems or http://search.datapages.com]


Summary:

Pg. 579 (fig. 3), 587-589. Four Mile Dam formation. Overlies Alpena limestone. Includes Dock Street clay member at base. Thickness at type section 8 feet; thickness where Dock Street clay member is present about 16 feet. Included in Traverse group.

Source: US geologic names lexicon (USGS Bull. 1200, p. 1408).


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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