Morrison Fm and Wanakah Fm (Junction Creek Sandstone Member at or near top; Pony Express Limestone Member at base)

Wanakah Fm: Sandstone, shale, limestone, and local gypsum
State Colorado
Name Morrison Fm and Wanakah Fm (Junction Creek Sandstone Member at or near top; Pony Express Limestone Member at base)
Geologic age Jurassic
Lithologic constituents
Major
Sedimentary > Clastic > Mudstone
Sedimentary > Clastic > Mudstone > Claystone
Minor
Sedimentary > Carbonate > Limestone
Sedimentary > Clastic > Sandstone
Sedimentary > Clastic > Mudstone > Shale
Incidental
Sedimentary > Chemical > Evaporite > Gypsum
References

Tweto, Ogden, 1979, Geologic Map of Colorado: U.S. Geological Survey Special Geologic Map, scale 1:500,000.

NGMDB product
Counties Archuleta - Gunnison - Montrose