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  • Usage in publication:
    • Keensburg Coal Member
  • Modifications:
    • Named
  • Dominant lithology:
    • Coal
  • AAPG geologic province:
    • Illinois basin
Publication:

Nance, R.B., and Treworgy, C.G., 1981, Strippable coal resources of Illinois; Part 8, Central and southeastern Counties: Illinois Geological Survey Circular, no. 515, 32 p.


Summary:

Coal exposed at McClearys Bluff, Wabash County, IL, is here named the Keensburg Coal Member of the Mattoon Formation of the McLeansboro Group. The coal lies 7 ft above the McClearys Bluff Coal Member and 50 to 55 ft above the Friendsville Coal Member of the Mattoon Formation. Thickness at type section is 1 ft. Age is Late Pennsylvanian (Missourian).

Source: GNU records (USGS DDS-6; Reston 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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