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Paleozoic rocks, undifferentiated

Paleozoic rocks, undifferentiated: in east-central Madison County where scale did not permit differentiation on map.
State Montana
Name Paleozoic rocks, undifferentiated
Geologic age Phanerozoic | Paleozoic
Primary rock type carbonate
Secondary rock type mudstone
Other rock types sandstone; chert; conglomerate
Lithologic constituents
Sedimentary > Carbonate (Bed)
Sedimentary > Clastic > Mudstone (Bed)
Sedimentary > Clastic > Sandstone (Bed)
Sedimentary > Chemical > Chert (Bed)
Sedimentary > Clastic > Conglomerate (Bed)
Map references
Ross, P.R., Andrews, D.A., and Witkind, I.J., 1955, Geologic map of Montana: U.S. Geological Survey, 2 sheets, scale 1:500,000.
Unit references
Hirsch, T.L., and Hyndman, D.W., 1985, Evolution of Square Butte laccolith, eastern Highwood Mountains, Montana: Northwest Geology, v. 14, p. 17-31.
Tysdal, R.G., and Simons, F.S., 1985, Geologic map of the Madison Roadless Area, Gallatin and Madison Counties, Montana: U.S. Geological Survey Miscellaneous Field Studies Map MF-1605-B, 1 sheet, scale 1:96,000.
Counties Madison