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State Missouri
Geologic age Phanerozoic | Paleozoic | Ordovician
Comments Undifferentiated Ordovician Rocks-Predominantly dolomite and limestones and some important sandstone and shale units. Ordovician age rocks are exposed over approximately one-third of the state. The Canadian, Champlainian, and Cincinnatian Series all represented. The Canadian, Champlainian Series being the most extensive.
Primary rock type dolostone (dolomite)
Secondary rock type limestone
Other rock types sandstone; shale
Lithologic constituents
Sedimentary > Carbonate > Dolostone (Bed)
Sedimentary > Carbonate > Limestone (Bed)
Sedimentary > Clastic > Sandstone (Bed)
Sedimentary > Clastic > Mudstone > Shale (Bed)
Map references
Middendorf, M. A., and others, 2003, Geologic Map of Missouri: Missouri Geological Survey. Scale 1:500K
Unit references
Howe, W. B. and Koenig, 1961, The Stratigraphic Succession in Missouri: Missouri Geological Survey and Water Resources, Vol XL. 2nd Series.
Counties Bollinger - Franklin - Montgomery - Saint Charles - Saline - Warren