Analogue and numerical modeling of the Stromboli hot avalanches

Hot avalanches at Stromboli volcano were investigated by means analogue and numerical modeling. Analogue experiments were performed with the aim of understanding the effects of different trigger mechanisms of slope instability while the runout of Stromboli hot rock avalanches was modeled using two numerical codes DAN-W (2D version) and DAN-3D. The accumulation experiments demonstrate that the accretion of a portion of the slope alters the flank stability and triggers small landslides. Numerical models were able to reproduce the extension and the order of magnitude of the thickness of the hot avalanches reported in the literature. The best results of DAN-3D and DAN-W models on the 1930 hot avalanche were obtained using a Voellmy model with a frictional coefficient f = 0.19 and a turbulence parameter ξ = 1000 m/s.. The obtained results allowed to produce a hazard evaluation for the explosive-related, mass-wasting phenomena in the inhabited areas of Stromboli Island.