Uranium-series dating of the draining of an aquifer: The example of Wind Cave, Black Hills, South Dakota

Wind Cave, South Dakota, is a three-dimensional, rectilinear maze cave developed in 90 m of Mississippian limestone and dolomite that is overlain by thick clastic cover strata. Beneath an area of 1.8 km2, 87 km of small, drained, phreatic passages are known. Exploration terminates at a water table 160 m below the highest parts of the cave. As the cave was draining, calcite precipitated from its waters. Uranium-series measurements (85) were …