Usage:
Hidden Falls Bed of McGregor Member of Platteville Formation (MN)
Geologic age:
Late Ordovician (Mohawkian; Turinian)
Type section, locality, area and/or origin of name:
Type section: in Hidden Falls Park, on the Mississippi River 0.5 mi south of Ford Motor Company plant, St. Paul, Ramsey Co., MN (Sloan, 1956).
AAPG geologic province:
Sioux 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 ([ ]).