Gypsum Spring Formation, Nugget Sandstone, and Chugwater Formation

Gypsum Spring Formation - Interbedded red shale, dolomite, and gypsum. In north Wyoming wedges out south in T. 39 N. Nugget Sandstone (JTRn) - gray to dull-red, crossbedded quartz sandstone. Chugwater Formation - Red siltstone and shale. Alcova Limestone Member in upper middle part in north Wyoming. Thin gypsum partings near base in north and northeast Wyoming.
State Wyoming
Name Gypsum Spring Formation, Nugget Sandstone, and Chugwater Formation
Geologic age Lower Triassic-Upper Jurassic
Lithologic constituents
Major
Sedimentary > Carbonate > Dolostone
Sedimentary > Clastic > Mudstone > Shale
Sedimentary > Clastic > Sandstone
Minor
Sedimentary > Carbonate > Limestone
Sedimentary > Clastic > Siltstone
Incidental
Sedimentary > Chemical > Evaporite > Gypsum
References
NGMDB product
Counties Washakie