Longitudinal stream profiles can be used to evaluate landscape evolution. Lithology as a control on a stream profile is especially of interests because fluviokarst systems are characterized by the contact of carbonate and non-carbonate rocks at the surface. Due to the difference in weathering processes between carbonates and non-carbonate rocks, it is likely that there is a difference in their rates of erosion. Cave Branch and its tributary Horn Hollow, are fluviokarst systems located in

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... stern Kentucky. This area is primarily comprised of sandstone and limestone. The objectives of this study were to determine if variation in lithology was creating a state of disequilibrium in the Cave Branch and Horn Hollow watersheds, determine whether sandstone or limestone erode at a faster rate in this system, and to assess how erosional resistance is related to the overall development of the system. Stream profiles were compared by calculating stream power values using an integral approach in which chi plots were created. This method allows for the comparison of streams of different drainage areas because erosion is scaled with drainage area. It was determined that sandstone watersheds were generally in a greater degree of equilibrium than the limestone watersheds, but whether variation in lithology was creating a state of disequilibrium in the whole watersheds was inconclusive. Limestone streams were determined to have a greater steepness index, greater resistance, than sandstone streams. The greater degree of disequilibrium and observed greater resistance of the limestone is related to the soluble nature of limestone, and the glacial-fluvial development of this area.