SPECULATIONS ON THE EVOLUTION OF GROUNDWATER BASINS IN THE MAMMOTH CAVE REGION, KENTUCKY (Invited Presentation)

The Mammoth Cave Region contains 29 recognized major groundwater basins, plus additional sub-basins, all of which discharge at springs on the Green, Barren, and Little Barren Rivers. The size of these basins ranges from less than 1 square mile with an estimated base flow of 0.1 cfs, to 295 square miles with an estimated base flow of 40 cfs. Further, these basins, as delineated by dye tracing, exhibit a wide diversity of plan form, especially when considered separately from their areas drained by surface streams. It is interesting to speculate about the relationships between the distribution of these basin characteristics and the structure, surface erosion history, stratigraphy, and probable hydraulic potential fields within the aquifer. It would appear that the basins formed sequentially from the east toward the west as the sandstone caprock was breached by the Green River. The centrally located Mammoth Cave Basin was pirated by the later forming Turnhole Basin. TheTurnhole Basin having a lower discharge point than the Mammoth Cave Basin. This paper complements the analyses by Deike (1967) and by Miotke and Palmer (1972) of the age and development of Mammoth Cave