Usage:
Black River Group (NY*,PA*,WV*,VA*,IN,VT*)
Black River Limestone (IL*,IN*,MI*,NY*,OH*,PA*,WV*)
Black River Formation (MI*)
Subunits:
GROUP STATUS (alphabetical): Amsterdam Limestone (NY*), Deicke K-bentonite Bed (subsurface of OH*,PA*,WV*), Gull River Limestone (NY), Hatter Formation (PA*) or Hatter Limestone (PA*), Isle La Motte Limestone (NY,VT), Linden Hall Limestone (PA*), Lowville Limestone (NY*,PA*,VT) or Lowville Formation (NY,VT), Pamelia Limestone (NY*) or Pamelia Formation (NY) or Pamelia Dolostone (NY), Pecatonica Formation (IN-subsurface), Peery Limestone (VA*,WV*), Plattin Formation (IN), Selby Limestone (NY), Snyder Limestone (PA*,VA,WV), Ward Cove Limestone (VA*,WV*), Wardell Formation (VA*, WV*), Watertown Limestone (NY*), Witten Limestone (VA*,WV*).
Geologic age:
Late Ordovician (late Whiterockian to Mohawkian; late Chazyan to early Chatfieldian)*
Type section, locality, area and/or origin of name:
Named from exposures in cliffs of Black River, north-central NY (Vanuxem, 1842).
AAPG geologic province:
Appalachian basin*
Michigan basin*
New England province*
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 ([ ]).