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Map showing publication footprint
  • Usage in publication:
    • Oak Grove member
  • Modifications:
    • Original reference
  • Dominant lithology:
    • Limestone
    • Shale
  • AAPG geologic province:
    • Illinois basin
Publication:

Wanless, H.R., 1931, Pennsylvanian cycles in western Illinois, IN Papers presented at the Quarter centennial celebration of the Illinois State Geological Survey: Illinois Geological Survey Bulletin, no. 60, p. 179-193.


Summary:

Oak Grove member of the Carbondale formation. Name applied to 20+/- feet of undescribed beds of alternating limestones and shale in lower part of Carbondale formation of central western Illinois. Said to underlie Purington shale and overlie his [H.R. Wanless'] Francis Creek shale, which rests on coal No. 2. Age is considered Pennsylvanian.
Origin of name not stated.

Source: US geologic names lexicon (USGS Bull. 896, p. 1524).


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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