New Theory of Recharge to the Artesian Basin of the Dakotas

Regional flow in the Dakota aquifer: A study of the role of confining layers

“…More recently, Swenson (1968) again questioned the ability of the Dakota system to transmit the quantity of water known to have been produced in eastern South Dakota under the existing hydraulic gradients. He, too, emphasized the differences in the chemistry of the Dakota water.…”

“…He went on to suggest that the bulk of Dakota water in eastern South Dakota is recharged from these underlying Madison Group limestones. It is implicit in Swenson's (1968) remarks that he thought the system was very nearly in steady state with little or no water still being derived from storage. The suggestion that the Dakota is recharged by water from the Madison Group limestones had been stated previously by Dyer and Goehring (1965) in a study of the Dakota aquifer in southeastern South Dakota.…”

“…The ground-water system is dominated by three major aquifers (Darton, 1909;Gries, 1958;Swenson, 1968;Schoon, 1971). The areas of aquifer outcrop are shown in figure I A, and a schematic cross section of the aquifers and their confining layers is presented in figure IB.…”

“…The areas of aquifer outcrop are shown in figure I A, and a schematic cross section of the aquifers and their confining layers is presented in figure IB. The lowest aquifer, primarily Mississippian carbonate rocks collectively called the Madison Group, terminates in the subsurface beneath the Inyan Kara Group sandstones (Swenson, 1968;Schoon, 1971). The Inyan Kara Group and the Newcastle Sandstone, both distinct aquifers in the western portion of the State, merge to form the Dakota Sandstone in the eastern part of the State (Gries, 1958;Schoon, 1971).…”

Study and interpretation of the chemical characteristics of natural water

“…The geology and hydrology of the system are complex (Swenson, 1968) and at least some of the solutes in water from the sandstone must originate from rocks other than the Dakota. Analysis 8, table 14, shows the composition of water obtained from the Dakota Sandstone in southeastern North Dakota.…”