Usage:
Slope Formation of Fort Union Group (ND)
(†Slope Formation of Fort Union Group not used by the USGS. Rocks reallocated to Ludlow Member of Fort Union Formation. See also Ludlow.)
Geologic age:
early Tertiary (Paleocene)
Type section, locality, area and/or origin of name:
Type section: south-facing exposure [along Little Missouri River], in northwestern corner sec. 15, and southwestern corner sec. 10, T. 105 N., R. 135 W., [Three V Crossing 7.5-min quadrangle, Little Missouri National Grassland], Slope Co., southwestern ND. Named from Slope Co. (Clayton and others, 1977).
Type area: in T. 105 N., R. 135 W., Slope Co., southwestern ND (Clayton and others, 1977).
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 ([ ]).