Usage:
Establishment Shale Member of Bloomsdale Limestone of Plattin Group (MO)
Establishment Member of Mifflin Formation of Platteville Group (IL)
Establishment Shale of Plattin Group (IL*,MO*)
Geologic age:
Late Ordovician (Mohawkian; Turinian)*
Type section, locality, area and/or origin of name:
Type section: exposure in tributary ravine just north of village of Zell, Ste. Genevieve Co., eastern MO. Named from Establishment Creek (Templeton and Willman, 1963).
AAPG geologic province:
Illinois basin*
Ozark uplift*
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 ([ ]).