Abstract:

Identifying cave levels provides insight into cave development and climatic changes that have affected a karst system over time. Cosmogenic dating has been used to interpret levels in Mammoth Cave and the Cumberland Plateau. This absolute dating technique has proven successful in determining cave paleoclimates and regional geomorphic history, but is expensive. The study presented here is a preliminary method to cosmogenic dating that can outline a region’s speleogenesis using a Geographic Information System (GIS) and published denudation rates. The Carter Cave system in northeastern Kentucky is within the karst landscape found along the western edge of the Appalachians and contains multiple daylighted caves at various elevations along valley walls. These characteristics make the Carter Caves an ideal location to apply GIS to cave level identification and evolution as described by Jacoby et al. (in review), who identified the cave levels within the area. The authors concluded that an argument can be made for either four or five cave levels in the Carter Cave system; however, studies identified four levels in both Mammoth Cave and the Cumberland Plateau. Further analysis indicated that the fifth level formed as a result of a change in lithology rather than an event that influenced the local base level. This research is an extension of the conclusions presented by Jacoby et al. (in review). The GIS was used to calculate the volume of surficial material lost within each level as a result of degradational geomorphic processes. Then, level thickness lost and published denudation rates were used to calculate the relative time required to form each level. There was not one denudation rate applicable to each level within the cave system, but the rates varied between 12 m/Ma and 40 m/Ma. This study concludes that the cave system took between 3.4 and 5.7 Ma to form. This study did not perform an absolute dating of cave sediments or assess any detailed stratigraphic influence.