Ozark Plateau Karst Aquifers
The Ozark Plateaus aquifer system consists mostly of carbonate rocks that are Cambrian through Mississippian in age. The sedimentary rocks are on the western flank of the Ozark Uplift, which is a dissected dome centered in Missouri. The regional dip of the rocks is westward and southwestward. The aquifer system consists of two aquifers and an intervening confining unit.
The uppermost aquifer is the Springfield Plateau aquifer, which consists of the Keokuk Limestone and the Reeds Spring and the St. Joe Limestone members of the Boone Formation. The rocks are mainly chert and limestone with solution-enlarged openings and local cavernous zones. The Springfield Plateau aquifer has a maximum thickness of about 500 feet in Oklahoma and contains water under unconfined to confined conditions. Yields of wells completed in the aquifer range from a few gallons per minute to more than 80 gallons per minute, whereas springs that issue from the aquifer might discharge as much as 3,500 gallons per minute. A confining unit that consists of rocks of Ordovician, Devonian, and Mississippian age and is called the Ozark confining unit separates the Springfield Plateau aquifer from the Ozark aquifer.
The Ozark aquifer, which is known locally as the Roubidoux aquifer, consists of dolomites and sandstones within the Roubidoux, the Gasconade, the Eminence, and the Potosi Formations of Ordovician and Cambrian age. The thickness of the Ozark aquifer ranges from 200 to 500 feet. Much of the water in the aquifer is in fractured dolomite and sandy zones where it is under confined conditions. Wells completed in the Ozark aquifer commonly yield from 50 to 250 gallons per minute and locally yield as much as 1,000 gallons per minute.
There are 2 USGS scientists you can contact for more information about this aquifer.