Usage:
Filer Sandstone Lentil of Amherstburg Formation (MI*-recognized locally in subsurface)
Geologic age:
Middle Devonian*
Type section, locality, area and/or origin of name:
Type section (subsurface): Ruggles and Rademacher well 24, in sec. 12, T. 21 N., R. 17 W., Filer Twp., Manistee Co., MI. Confined for most part to western flank of Michigan basin (Landes, 1951).
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 ([ ]).