Reconstruction of the 1783 Scilla landslide, Italy: numerical investigations on the flow-like behaviour of landslides

This paper presents a mass flow model that includes gravity force, material stresses, drag force and topography effects solving a set of hyperbolic partial differential equations by using a so-called depth-averaged technique. The model is non-linear and general enough to tackle various problems of interest for geophysics and environmental engineering, such as the dynamic evolution of flow-like avalanches, the dam break problem (involving only water flow) and the generation of tsunami waves by landslides. The model is based on a Eulerian fluid solver, using a second-order central scheme with a minmod-like limiter; is tested against a number of typical benchmark cases, including analytical solutions and experimental laboratory data; and also compared with other numerical codes. Through this model, we study a historical tsunamigenic event occurred in 1783 in Scilla, Italy, that resulted to be catastrophic with a toll exceeding 1500 fatalities. The landslide is reconstructed by a mixture debris flow, and results are compared with the observational data and other numerical simulations.