PHOSPHORIA FORMATION AND RELATED ROCKS
  Thrust belt--Upper part is dark- to light-gray chert and shale with black shale and phosphorite
     at top; lower part is black shale, phosphorite, and cherty dolomite.  Pp, P&Ma
  Northern Yellowstone area--Brown sandstone and dolomite, cherty phosphatic and glauconitic
     dolomite, phosphatic sandstone and dolomite, and greenish-gray to black shale.  Inter-
     tonguing equivalent is Shedhorn Sandstone.  P&Ma
  North Wyoming--Brown sandstone and dolomite, cherty phosphatic and glauconitic dolomite,
     phosphatic sandstone and dolomite, and greenish-gray to black shale.  Intertonguing
     equivalents of parts of Phosphoria are Park City Formation (primarily cherty
     dolomite, limestone, and phosphatic gray shale) and Shedhorn Sandstone.  Pp, P&Ma, MzPz
FORELLE LIMESTONE--Thin-bedded limestone.  Locally is a member of the Goose Egg
     Formation.  @Pjs, Pfs
SATANKA SHALE--Red shale  @Pjs, Pfs
MINNEKAHTA LIMESTONE--Gray slabby hard limestone.  Locally is a member of the
     Goose Egg Formation.  Pmo, Pzr
OPECHE SHALE--Red soft sandy shale.  Locally is a member of the Goose Egg
     Formation. Pmo, Pzr