Usage:
Hecla Beds of Red River Formation of Bighorn Group (subsurface of MT,ND,SD)
Is approx. same as Roughlock Siltstone Member of Winnipeg Formation of surface terminology. See also Roughlock.
Geologic age:
Middle Ordovician
Type section, locality, area and/or origin of name: (See Canadian Lexicon)
Not designated. Named from Hecla Island near Grindstone Point on the west shore of Lake Winnipeg, Manitoba, Canada (Fuller, 1961).
AAPG geologic province:
Williston 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 ([ ]).