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National Geologic Map Database

Geologic Unit: Knobs

Usage:

Knobs Supergroup (KY)
Knobs Group (IL)


Subunits:

GROUP STATUS (alphabetical) --all in IL: Borden Siltstone, Chouteau Limestone, Meppen Limestone, New Albany Shale, Springville Shale; [interpreted from Kolata (2005) and Willman and others (1975, p. 127)].


Geologic age:

Devonian to
Mississippian


Type section, locality, area and/or origin of name:

Not designated. Named from "The Knobs," a narrow band of highly dissected terrain developed on Late Devonian and Early Mississippian shales that partially surrounds Bluegrass region and lies in front of Highland Rim, Muldraugh, or Knobstone Escarpment of KY (Swann and Willman, 1961).


AAPG geologic province:

Illinois basin


For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.

Asterisk (*) indicates usage by the U.S. Geological Survey. Other usages by state geological surveys.

"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 does not conform with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). This may be explained within brackets ([ ]).