From granular collapses to shallow water waves: A predictive model for tsunami generation

Sudden large-scale geophysical flows such as cliff collapses, rockfalls, or massive landslides are known to be tsunamigenic and constitute a significant hazard for coastal populations and infrastructures. A key challenge is to be able to predict a priori the amplitude of the tsunami wave that would be engendered by a given cliff collapse. In this study, we introduce a comprehensive model of shallow water waves generated by the subaerial collapse of a granular column. The proposed model is able to capture the role of the geometry of the collapse as well as the water depth and is successfully compared to a large dataset of experiments.