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National Geologic Map Database

Geologic Unit: Monongahela

Usage:

Monongahela Formation (MD*,OH*,PA*,WV*)
Monongahela Group (PA*,OH,WV*)


Subunits:

GROUP STATUS: Uniontown Formation (PA*,WV), Benwood Limestone (OH), Sewickley Sandstone (PA), and Pittsburgh Formation (PA*).
FORMATION STATUS: Big Run Sandstone [Bed] (OH), Gilboy Sandstone Member (OH*,PA*,WV*), Little Captina Limestone Member (OH*), McKeefrey Siltstone Member (OH*,PA*,WV*), Morning View Sandstone Member (OH*,PA*,WV*), Redstone Member (WV*), Ritchie Red Beds (OH,WV).


Geologic age:

Pennsylvanian, Late*


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

Type area: Exposures along Monongahela River, southwest PA (Rogers, 1840).


AAPG geologic province:

Appalachian basin*


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