Tioga Ash Bed (NY*,OH*,PA*,WV*)
Tioga Bentonite Bed of Grand Tower Limestone (IL)
Tioga Bentonite Bed of Jeffersonville Limestone (IN)
Tioga Bentonite Bed of Cranberry Marsh Member of Detroit River Formation (IN)
Tioga Bentonite Bed of Grover Ditch Member of Detroit River Formation (IN)
Tioga Bentonite Bed of Vernon Fork Member of Jeffersonville Limestone (IN)
Tioga Bentonite Bed of Onondaga Limestone (MD,PA,VA)
Tioga Bentonite Bed of Columbus Limestone (OH)
Tioga Bentonite Bed of Onondaga Member of Romney Shale (WV)
early Middle Devonian (Eifelian)*
Named from Tioga gas field, Tioga Co., PA. First recognized there in drill cuttings.
Appalachian basin*
Cincinnati arch
Illinois 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 conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).