Reply to comment by Chen et al. on "Controls on the size and geometry of landslides: Insights from discrete element numerical simulations"

Chen et al.'s comment presents limit equilibrium (LE) calculations of slope stability, which yield different landslide geometries compared with those obtained by Katz et al. (2014) using the Discrete ElementMethod (DEM). Previous work, however, has demonstrated excellent agreement in the slide geometries and sizes obtained by DEMvs. those obtained by limit analysis, thereby lending confidence to DEM and to limit analysis as methods to study slope instability and geometry. We suggest three reasons why the LE results may differ from DEM: (1) LE is a static method, which seeks a single failure surface to predict slope stability. Although it captureswell the average slope conditions, the details of the stress distributionmay be inaccurate. (2) DEM is a dynamicmethod that holistically simulates the evolution of stress and strain. Thus it is better suited to simulate far fromequilibriumsituations, such as overly steep slopes with FS b 1, which have strong dynamic responses. (3) The geometries of the slides presented by Chen et al. appear to be constrained by the domain size. We expect that a larger simulation domain may allow exploration of additional slide geometries, potentially with better correspondence with those of the DEM simulations.