Bois Blanc Formation (MI*,NY*,OH,PA)
Bois Blanc Limestone of Tristates Group (NY)
Early Devonian*
Named from exposures on Bois Blanc Island situated in Lake Huron about 2.5 mi southeast of Mackinac Island, MI (Ehlers, 1945).
Michigan 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 ([ ]).