Minnekahta Limestone and Opeche Shale (SDPmo;0)

Minnekahta Limestone-Purple to gray, finely crystalline, thin- to medium-bedded limestone with varying amounts of red shale. Thickness 30-50 ft (9-15 m). Opeche Shale- Red siltstone, argillaceous sandstone and shale interbedded with caliche layers. Thickness 85-130 ft (26-40 m).

State	South Dakota
Name	Minnekahta Limestone and Opeche Shale
Geologic age	Phanerozoic \| Paleozoic \| Permian
Original map label	Pmo
Primary rock type	siltstone
Secondary rock type	sandstone
Other rock types	shale; limestone
Lithologic constituents	Major Sedimentary > Carbonate > Limestone (Bed) Sedimentary > Clastic > Mudstone > Shale (Bed) Sedimentary > Clastic > Sandstone (Bed) Sedimentary > Clastic > Siltstone (Bed)
Map references	Martin, J. E., Sawyer, J. F., Fahrenbach, M. D., Tomhave, D. W., and Schulz, L. D., 2004, Geologic Map of South Dakota: South Dakota Geological Survey
Unit references	Martin, J. E., Sawyer, J. F., Fahrenbach, M. D., Tomhave, D. W., and Schulz, L. D., 2004, Geologic Map of South Dakota: South Dakota Geological Survey
Geographic coverage	Custer - Fall River - Lawrence - Meade - Pennington