Geologic units in Laclede county, Missouri

Roubidoux Formation (Early Ordovician-Ibexian Series) at surface, covers 51 % of this area

Sandstone, chert and interbedded dolomite

Smithville Dolomite, Powell Dolomite, Cotter Dolomite, Jefferson City Dolomite (Early Ordovician-Ibexian Series) at surface, covers 41 % of this area

Fine crystalline, silty, cherty dolomite, and oolitic chert with local sandstone beds.

Gasconade Dolomite (Early Ordovician-Ibexian Series) at surface, covers 9 % of this area

Coarse - crystalline cherty dolomite with a basal Gunter Sandstone Member.

Eminence Dolomite, Potosi Dolomite (Late Cambrian-Croixian Series) at surface, covers < 0.1 % of this area

Eminence Dolomite - dolomite with some druse - coated chert. Potosi Dolomite - dolomite with abundance of druse - coated chert.

Elvins Group - (including Derby-Doerun Dolomite, Davis Formation), Bonneterre Dolomite (Late Cambrian-Croixian Series) at surface, covers < 0.1 % of this area

Derby-Doerun Dolomite - alternating thin dolomite, siltstone, and shale; Davis Formation - glauconitic shale with fine - grained sandstone, limestone, and dolomite); Bonneterre Dolomite - dolomite, dolomitic limestone, and limestone; glauconitic in lower part.

Pennsylvanian Undifferentiated (Pennsylvanian) at surface, covers < 0.1 % of this area

Pennsylvanian Undifferentiated

Lamotte Sandstone (Late Cambrian-Croixian Series) at surface, covers < 0.1 % of this area

Sandstone with some dolomitic and shaly lenses; coarse - graines to conglomeratic and arkosic at base.

Osagean Series (Early Mississippian-Osagean Series) at surface, covers < 0.1 % of this area

Keokuk Limestone, Burlington Limestone, Elsey Formation, Reeds Spring Formation, Pierson Limestone, Fern Glen Formation.