Tectonic Unit: TrJS
         Name: Spray River

  Description: Jurassic shale, organic-rich paper shale,         
               sandstone, phosphatic and cherty limestone;       
               Triassic shoaling-upward marine siltsone,         
               sandstone, limestone, dolostone, collapse breccia,
               rare gypsum; marine                               

    Formation: Omineca Belt  
                  Ancestral North America 
                     J    Lower schist 
                     lmTr Jones L. 
               Foreland Belt  
                  Ancestral North America 
                     KTr  Glenn (lower part) 
                     JK   Kingak (lower part) 
                     mJ   Aklavik, lower Ellis: Rierdon, Sawtooth 
                     lmJ  Bug Cr.: 
                     mJ   Richardson Mtns. 
                     lJ   Manuel Cr., Almstrom Cr., Murray Ridge 
                     lmJ  Fernie (lower part) 
                     Tr   Spray R.: 
                     uTr  Whitehorse, Starlight 
                     lmTr Sulphur Mtn. 
                     uTr  Bocock, Pardonet, Ludington, Baldonnel, Charlie L. 
                     mTr  Liard 
                     lmTr Toad 
                     lTr  Grayling                                 

    Age Range: Triassic - Jurassic
  Maximum Age: 245.0 Ma
  Minimum Age: 145.6 Ma