Usage:
Grant Lake Limestone (KY*,OH*)
Grant Lake Formation (OH*)
Grant Lake Formation of Cincinnati group (informal) (OH)
Grant Lake Limestone of Cincinnati group (informal) (OH)
Grant Lake Member of Ashlock Formation (KY*)
(informal Cincinnati group is the usage of the OH Geol. Survey. The rank or lithologic term should not be capitalized.)
Subunits:
FORMATION STATUS (alphabetical): Bellevue Member (KY,OH*) or Bellevue Limestone Member (OH*) or Bellevue Tongue (IN,KY*,OH), Corryville Member (KY,OH*) or Corryville Shale Member (OH*), Mount Auburn Member (OH*), Straight Creek Member (OH,KY), Tate Member (KY*).
Geologic age:
Late Ordovician (Cincinnatian; Maysvillian)*
Type section, locality, area and/or origin of name:
Type section: roadcuts along KY Highway 1129 about 4 mi north-northwest of Orangeburg, Mason Co., KY (Peck, 1966).
AAPG geologic province:
Cincinnati arch*
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 ([ ]).