Usage:
Cataract Formation (MI*,IN)
Cataract Group (MI,OH)
Subunits:
FORMATION STATUS: Stroh Member (IN), Cabot Head Member (MI*,IN), and Manitoulin Member (MI*,IN).
GROUP STATUS: Moss Lake Formation (MI), Cabot Head Shale (MI), Cabot Head Formation (OH), Manitoulin Dolomite (MI), Manitoulin Formation (OH), Brassfield Formation (OH), Clinton Dolomite (OH), Lockport Dolomite (OH), Bass Islands Formation (OH).
Geologic age:
Silurian*
Type section, locality, area and/or origin of name: (See Canadian Lexicon)
Cataract, Ontario, Canada (Schuchert, 1913).
AAPG geologic province:
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 ([ ]).