3D Tsunami modelling from submarine landslide in Gulf of Naples, Southern Tyrrhenian Sea, Italy

A modified version of the GEOWAVE (Watts, 2009) model is used, taking properly into account the decreasing nearshore tsunami wavelength through a system of nested grids. GEOWAVE simulates tsunami waves generation, propagation, and inundation using a fourth order fully nonlinear equations, fully dispersive Boussinesq wave model with multiple wave dissipation mechanisms, wave breaking, and dry land overflow. In the numerical simulation, the Tsunami Open and Progressive Initial Conditions System (TOPICS) is adopted to produce 3D tsunami source for tsunamis generated by submarine slides and slumps, while a 25 m uniform spacing grid is derived from the bathymetric dataset of the Naples Bay. Interesting results of tsunami simulation, in the above-mentioned areas, show that the amplitude of wave run-up ranges from 0.90 m near to Procida Island and up to 1.90m nearness of Naples Port. This difference in run-up is ascribed to a different coastal morphology. In fact, the port of Naples offshore has a slope of 3-4 degrees while the Procida Island offshore of 25-30 degrees.