Sundance Formation  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Mesozoic
 ...Jurassic
 ....Upper Jurassic
 .....Sundance Formation
RTWyoming
 Montana
 Colorado
 Nebraska
 South Dakota
SNIncludes Canyon Springs Sandstone, Stockade Beaver Shale, Hulett Sandstone, Lak, and Redwater Shale members. Central N Colorado, central S Montana, NW Nebraska, SW South Dakota, and SW Wyoming.