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National Geologic Map Database

Geologic Unit: Keefer

Usage:

Keefer Sandstone (KY*,MD*,OH*,PA*,VA*,WV*)
Keefer Sandstone of Clinton Group (MD,PA,WV)
Keefer Formation (PA,VA,WV)
Keefer Sandstone Member of Clinton Formation (PA*,VA)
Keefer Member of Mifflintown Formation (PA)
Keefer Sandstone Member of Mifflintown Limestone (PA*)


Geologic age:

Silurian (Llandovery to Ludlow; Niagaran Provincial Age)


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

Named from Keefer Mountain, [Cherry Run and Big Cove Tannery 7.5-min quadrangles, Franklin Co., southern PA], a few mi northeast of Hancock, MD (Ulrich, 1911; Stose, 1912; US geologic names lexicon, USGS Bull. 1200).


AAPG geologic province:

Appalachian 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 ([ ]).