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National Geologic Map Database
Map showing publication footprint
  • Usage in publication:
    • Red River formation*
  • Modifications:
    • Revised
  • AAPG geologic province:
    • Williston basin
Publication:

Ross, R.J., Jr., 1957, Ordovician fossils from wells in the Williston basin, eastern Montana, IN Contributions to general geology, 1955: U.S. Geological Survey Bulletin, 1021-M, p. M439-M510.


Summary:

Assigned to Bighorn group as lower of two formations in subsurface of Williston basin. Cores studied are from wells in Roosevelt, Dawson, Wibaux and Fallon Cos, MT. Overlies Winnipeg formation; underlies Stony Mountain formation (revised) of Bighorn. Cross section of wells; fossil description and distribution. Late Ordovician (Cincinnatian) age.

Source: GNU records (USGS DDS-6; Denver 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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