|Name||Ste. Genevieve Limestone|
|Geologic age||Mississippian (Visean)|
Sedimentary > Carbonate > Limestone (Bed)Limestone can be oolitic, shaly or sandy.
Sedimentary > Clastic > Sandstone (Bed)Sandstone can be shaly or argillaceous.
|Comments||Thickness from stratigraphic columns: Ste. Genevieve Ls (0-400’) in southern Illinois (south of 40 degrees north latitude); Ste. Genevieve Ls (0-80’) in northern Illinois (north of 40 degrees north latitude). Ste. Genevieve Limestone includes, from oldest to youngest, Fredonia Ls Mbr - “McClosky”, Spar Mountain Ss Mbr - “Rosiclare” Ss Mbr, Karnak Ls Mbr - “Ohara”, and “Aux Vases lime” in southern Illinois. The Ste. Genevieve Limestone is the uppermost formation of the Mammoth Cave Group. [The 'Mbr' designators were derived from Geolex IL005 reference.][Oil well drillers' terms shown in quotation marks.]|
|Stratigraphic units||Fredonia Ls Mbr - “McClosky”, Spar Mountain Ss Mbr - “Rosiclare” Ss Mbr, Karnak Ls Mbr - “Ohara”, “Aux Vases lime”|
Kolata, D.R., comp., 2005, Bedrock Geology of Illinois: Champaign, Ill., Illinois State Geological Survey, Illinois Map Series 14, scale 1:500,000.
USGS Geologic Names lexicon found at: http://ngmdb.usgs.gov/Geolex/
|Counties||Hardin - Johnson - Madison - Massac - Monroe - Pope - Pulaski - Randolph - Saint Clair - Union|