EXPLORING THE CONTROLS OF KARSTIFICATION BY ANALYZING KARST SURFACE DRAINAGE ACROSS THE UNITED STATES (Invited Presentation)

Karst conduit networks enable transport of solid and dissolved weathering products through the subsurface, bypassing the hillslopes and surface streams that carry those materials in non-karstic terrains. This subsurface transport weakens coupling between tectonic uplift and landscape erosion and may strongly influence the evolution and dynamics of the karst critical zone. However, we have limited understanding of the factors that control the partitioning of weathering fluxes between surface and subsurface routes. We develop a proxy for this flux partitioning by quantifying the extent to which a landscape drains into karst depressions versus into fluvial networks. Using available depression databases, the open-source python package HyRiver, which enables automatic queries to high resolution topographical data across the US, and Whitebox, an open-source terrain analysis tool, we developed scripts to conduct surface flow routing into karst depressions across the entire carbonate area of the US. This enabled us to partition the landscape into the portion that drains into karst depressions and the portion that drains into surface fluvial networks. We use these two areas to calculate the karst drainage percentage and examine how this drainage percentage relates to potential climatic and geological controls.