CASPER FORMATION--Gray, tan, and red thick-bedded sandstone underlain by interbedded 
     sandstone and pink and gray limestone.  May include some Devonian(?) sandstone
     along east flank of Laramie Mountains.  P&c, P&cf, P&M, MzPz
TENSLEEP SANDSTONE
  North Wyoming--White to gray sandstone containing thin limestone and dolomite beds.  Per-
     mian fossils have been found in the topmost beds of the Tensleep at some localities in
     Washakie Range, Owl Creek Mountains, and southern Bighorn Mountains.  P&Ma, PM, MzPz
  South Wyoming--White to gray sandstone containing thin limestone and dolomite beds.  PM,
     MzPz