Greenish-gray, olive-drab, and white tuffaceous sandstone and claystone; lenticular marlstone and conglomerate.
(Thrust Belt) Main body--Variegated red to gray, brown, and gray mudstone and sandstone; conglomeratic lenses. (in southwest Wyoming) - Drab to variegated claystone and siltstone, carbonaceous shale and coal, buff sandstone, arkose, and conglomerate. In northwestern part of Green River Basin is thick arkosic light-yellowish-tan sandstone intertonguing with pale-green to gray claystone and shale. (in east Wyoming) - Drab sandstone and drab to variegated claystone; numerous coal beds in lower part.
Clay, silt, sand, and gravel in flood plains, fans, terraces, and slopes.
Green River Formation (Thrust Belt) - Buff laminated marlstone and limestone, brown oil shale, and siltstone. Includes Angelo and Fossil Butte Members. Wasatch Formation (Thrust Belt) - Variegated mudstone and sandstone. Includes Tunp and Bullpen Members, other tongues and unnamed members, and main body (variegated red to gray, brown, and gray mudstone and sandstone; conglomerate lenses). Green River Formation (in southwest Wyoming) - Oil shale, light-colored tuffaceous marlstone, and sandstone. Wasatch Formation (in southwest Wyoming) - Drab to variegated claystone and siltstone, carbonaceous shale and coal, buff sandstone, arkose, and conglomerate. In northwestern part of Green River Basin is thick arkosic light-yellowish-tan sandstone intertonguing with pale-green to gray claystone and shale.
Locally includes intermixed landslide and glacial deposits, talus, and rock-glacier deposits.
Oil shale and marlstone.
Gray siltstone, sparse red sandstone, and lignite beds.
Dark-gray to tan claystone, siltstone, and sandy shale.
Partly consolidated gravel above and flanking some major streams.
Mostly alluvium, colluvium, and glacial and landslide deposits. Primarily in Yellowstone area and Bighorn Mountains.
(Thrust Belt) - White to brown sandstone and dark-gray shale; oyster coquina in upper part; coal and lignite in lower part. (North and South Wyoming) - Gray sandstone and sandy shale.
Light-colored tuffaceous sandstone and siltstone, locally conglomeratic. Locally designated by some as Norwood Tuff.
Till and outwash of sand, gravel, and boulders.
Sage Junction Formation - Gray and tan siltstone and sandstone. Quealy Formation - Variegated mudstone and tan sandstone. Cokeville Formation - Tan sandstone, claystone, limestone, bentonite, and coal. Thomas Form Formation - Variegated mudstone and gray sandstone. Smiths Formation - Ferruginous black shale and tan to brown sandstone.
Red sandy mudstone, sandstone, and chert-pebble conglomerate; thin limestone and dark-gray shale in upper part, more conglomeratic in lower part. Includes Smoot Formation (red mudstone and siltstone), Draney Limestone, Bechler Conglomerate, Peterson Limestone, and Ephraim Conglomerate. Upper Jurassic fossils have been reported from the Ephraim.
Mostly locally derived clasts. Includes some glacial deposits along east flank of Wind River Range. Locally includes some Tertiary gravels.
Green, brown, and gray tuffaceous sandstone, shale, and marlstone; contains evaporites in subsurface sections.
Gray sandstone, siltstone, and carbonaceous claystone; conglomeratic in upper part; coal-bearing in lower part.
Clasts of red quartzite, gray chert, and limestone in a gray to white tuffaceous sandstone matrix.
Light- to dark-gray siliceous tuffaceous shale and siltstone, thin bentonite beds, and quartzitic sandstone.
Includes active and dormant sand dunes. In northwestern Wyoming is chiefly loess (age 12,000-19,000 years).
Black shale, fine-grained brown sandstone, thin limestone, and bentonite beds.
Stump Formation - Glauconitic siltstone, sandstone, and limestone. Preuss Sandstone or Redbeds - Purple, maroon, and reddish-gray sandy siltstone and claystone; contains salt and gypsum in thick beds in some subsurface sections. Twin Creek Limestone - Greenish-gray shaly limestone and limy siltstone. Includes Gypsum Spring Member.
Older alluvial deposits
Alluvium and colluvium
Wasatch/Colton Formations and Flagstaff Limestone.