Duperow Formation  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Paleozoic
 ...Devonian
 ....Upper Devonian
 .....Duperow Formation
RTSaskatchewan
 Montana
 North Dakota
 Manitoba
 South Dakota
 Jefferson Group
SNIn Jefferson Group. North Dakota, NE Montana, NW South Dakota, Manitoba and Saskatchewan. Added to Thesaurus in 1985.