Morrison Formation  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Mesozoic
 ...Jurassic
 ....Upper Jurassic
 .....Morrison Formation
RTNew Mexico
 Utah
 Wyoming
 Montana
 Oklahoma
 Colorado
 Kansas
 Arizona
 South Dakota
 Brushy Basin Shale Member
 Salt Wash Sandstone Member
 Westwater Canyon Sandstone Member
SNIn Plata Mountains of Colorado, comprises (ascending) Pony Express Limestone, Bilk Creek Sandstone, Wanakah Marl (restricted), and Junction Creek Sandstone.