OPEN SOURCE TOOLS FOR TECTONIC GEOMORPHOLOGY: THE TOPOGRAPHIC ANALYSIS KIT (TAK) AND DIVIDETOOLS (Invited Presentation)

Quantitative analysis of digital topographic data is an increasingly important part of many studies in the geosciences and is a crucial component of modern tectonic geomorphology. Initially, performing these analyses was a niche endeavor, requiring detailed domain knowledge and programming skills, but increasingly broad, flexible, open source code bases have been developed to increasingly democratize topographic analysis. However, many of these still require specific computing environments and/or moderate levels of knowledge of the relevant programming language, general programming techniques, and the correct way to take these fundamental building blocks and conduct an efficient and effective topographic analysis. To partially address this, we have recently documented and released two sets of topographic analysis tools, the Topographic Analysis Kit (TAK) and DivideTools, which both leverage the power of one of these open source libraries, TopoToolbox, to build a series of high-level topographic analysis tools to perform a variety of common analyses. The functions included with TAK facilitate definition of stream networks and batch production of maps of normalized channel steepness and χ with proper treatment of outlet elevations and incomplete channel networks for maps, but also provide an update to established methodologies for fitting stream profile segments to measure normalized channel steepness originally introduced with the popular 'Stream Profiler' tool, and introduce a framework for efficiently partitioning landscapes into series of small non-overlapping watersheds for a 'basin-averaged' style of topographic analysis. Complimentary to TAK, DivideTools is a more focused set of functions for semi-quantitatively assessing the stability of drainage divides via a combination of across divide anomalies in χ, mean upstream local relief, mean upstream gradient, and channel elevation. Both sets of tools are released on GitHub. At present, TAK is released both as Matlab code and also compiled versions that are usable for users without access to Matlab (or all required toolboxes) via the free Matlab Runtime environment. A future compiled version of DivideTools is planned.