Usage:
Rivil subinterval (informal) of Frobisher-Alida interval (informal) in Mission Canyon Formation of Madison Group (ND-subsurface)
Informal. The rank or lithologic term should not be capitalized.
Geologic age:
Middle Mississippian (Visean; late Osagean)
Type section, locality, area and/or origin of name:
Named from producing interval in Rivil oil field, Burke Co., ND, by [M. H. Smith, 1960, "Revised nomenclature for the Williston basin [abs.]," Billings, MT, AAPG Rocky Mountain Section, 10th Ann. Mtg. Prog. w/ Abs. ] (see entry under Anderson and others, 1960).
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 ([ ]).