Usage:
Hemlock Formation of Menominee Group of Marquette Range Supergroup (recognized locally in MI*,WI*)
Hemlock Formation of Baraga Group of Marquette Range Supergroup (MI-local)
Notable exposures in Iron River-Crystal Falls district, Northern Peninsula.
Subunits:
(alphabetical) --all in MI: Bird Iron-Bearing Member*, [/?]Mansfield Iron-Bearing Slate Member*.
Geologic age:
Paleoproterozoic*
Type section, locality, area and/or origin of name:
Exposures along Hemlock River, Crystal Falls district, northeastern Iron Co., Northern Peninsula, northwestern MI (Clements, 1899).
AAPG geologic province:
Lake Superior region*
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 ([ ]).