COLIN PETER STARK2023-09-232023-09-232010-02-0100948276https://scholars.lib.ntu.edu.tw/handle/123456789/635726A simple model of topographic ridge evolution is developed in which mass-wasting is treated as a vectorial erosion process. Channel incision drives backcutting as well as downcutting of the connected hillslope and the result is a mobile drainage divide that exhibits sustained horizontal and vertical motions mediated by asynchronous, asymmetric channel incision rates. The model resolves a ridge cross-section into coupled hillslope and channel links and the model equations are found to form a lowdimensional, non-linear dynamical system. For weak forcing of hillslope erosion the system converges to a stable, symmetric geometry, but for strong forcing a limit cycle arises and the divide oscillates back and forth over time. The lessons to draw from this model are that such low-dimensional dynamical behavior: (i) may explain the sinuous planform of interfluves; (ii) may form a key constituent of the high-dimensional dynamics of landscape evolution as a whole.journal article10.1029/2009GL0408512-s2.0-77649101802https://api.elsevier.com/content/abstract/scopus_id/77649101802