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National Geologic Map Database

Geologic Unit: Antrim

Usage:

Antrim Shale (IL,IN*,MI*,OH,WI)


Subunits:

(alphabetical) --all in MI: /Chester black shale member (informal), , Lachine Member*, Norwood Member*, Paxton Member*.


Geologic age:

Late Devonian*


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

Named from Antrim Co., Lower Peninsula, MI, in which the shales are exposed (Lane, 1901).
Type locality: 1.6 km south of Norwood, along Lake Michigan (GNU records, USGS DDS-6; Reston GNULEX).


AAPG geologic province:

Michigan basin*
Wisconsin arch


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 ([ ]).