Rock Springs Formation  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Mesozoic
 ...Cretaceous
 ....Upper Cretaceous
 .....Rock Springs Formation
RTUtah
 Wyoming
 Mesaverde Group
 Hilliard Shale
SNIn Mesaverde Group. Includes McCourt Tongue and Glades coal bed. NE Utah and SW Wyoming. Added to Thesaurus in 1989.