Chugwater and Dinwoody Formations

Chugwater Formation - Red siltstone and shale. Alcova Limestone Member in upper middle part. Thin gypsum partings near base. Dinwoody Formation - Olive-drab hard dolomitic thin-bedded siltstone.
State Wyoming
Name Chugwater and Dinwoody Formations
Geologic age Lower Triassic-Upper Triassic
Lithologic constituents
Major
Sedimentary > Clastic > Siltstone
Sedimentary > Clastic > Mudstone > Shale
Minor
Sedimentary > Carbonate > Limestone
Incidental
Sedimentary > Chemical > Evaporite > Gypsum
References
NGMDB product
Counties Fremont - Hot Springs - Natrona - Park - Sublette - Teton - Washakie