Snowcrest Range and Tendoy Groups: Conover Ranch, Lombard, Kibbey, McKenzie Canyon, Mission Canyon, Middle Canyon, and Paine Formations

Snowcrest Range Group (PAMsr) - Conover Ranch Formation: Red siltstone and mudstone with minor silty limestone and sandstone beds. Thickness 35 m (115 ft). Lombard Formation: Gray, silty limestone with minor black shale. Thickness120 m (394 ft). Kibbey Formation: Yellow siltstone, sandstone, and mudstone with minor silt limestone in lower part. Thickness 80 m (262 ft). Tendoy Group (Mtd) - McKenzie Canyon Formation: Gray, chert-bearing limestone and solution breccia. Marine. Thickness 140 m (460 ft). Mission Canyon Formation: Light gray, chert-bearing limestone and brown dolomitic limestone. Shallow marine. Thickness 180 m (590 ft). Middle Canyon Formation (Mmd): Dark gray, silty limestone with chert beds and nodules. Shallow marine. Thickness at type section 335 m (1,100 ft). Paine Formation: Dark gray, silty limestone with solution breccia zone. Shallow marine. Thickness 230 m (755 ft).
State Montana
Name Snowcrest Range and Tendoy Groups: Conover Ranch, Lombard, Kibbey, McKenzie Canyon, Mission Canyon, Middle Canyon, and Paine Formations
Geologic age Pennsylvanian and Mississippian
Lithologic constituents
Major
Sedimentary > Carbonate > Limestone (Bed)
Sedimentary > Clastic > Siltstone (Bed)
Sedimentary > Clastic > Mudstone (Bed)
Minor
Sedimentary > Clastic > Sandstone (Bed)
Sedimentary > Clastic > Mudstone > Shale > Black-shale (Bed)
Incidental
Sedimentary > Chemical > Chert (Bed)
References

Vuke, S.M., Porter, K.W., Lonn, J.D., and Lopez, D.A., 2007, Geologic Map of Montana - Compact Disc: Montana Bureau of Mines and Geology: Geologic Map 62-C, 73 p., 2 sheets, scale 1:500,000. This map was digitized in 2012 as a result of a contract between the U.S. Geological Survey and the Montana Bureau of Mines and Geology.

NGMDB product
Counties Beaverhead