MODELING LANDSLIDE TSUNAMIS: REVIEW OF THE NTHMP BENCHMARKING WORKSHOP

Landslides and other forms of tsunamigenic submarine mass failures (SMF)'s form a significant component of the overall tsunami hazard in a number of settings worldwide. In recognition of the need for assessing both the skill of existing models and their limitations, the National Tsunami Hazard Mitigation Program (NTHMP) held the Landlside Tsunami Modeling Benchmark Workshop in January 2017. The workshop brought together over 30 modelers, experimentalists and field geologists. Prior to the workshop, modelers were provided with seven benchmark tests, with three selected for special attention and analysis: a submarine slide of a solid, elliptical body on a planar slope, a submarine granular slide in a laboratory flume, and a reconstruction of a field case involving two separate slides during the 1964 Alaska earthquake. In this talk, we review the various classes of hydrodynamic models employed (either (1) non-dispersive, shallow water models, (2) weakly-dispersive, Boussinesq-type models, (3) fully-dispersive non-hydrostatic models, and (4) Navier-Stokes models), and the modeled treatment of slide rheology (solid, fluid or granular) and provide a general assessment of model suitability by comparison to data. Finally, we review the implications of new geological information for the ongoing improvement of model formulations.