Probability hazard map for future vent opening at Etna volcano (Sicily, Italy).

Monday, 15 December 2014
Placido Montalto1, Alfonso Brancato1, Flavio Cannavo1, Mauro Coltelli2, Mario Mattia1, Domenico Patanè3, Cristina Proietti2 and Danila Scandura1, (1)National Institute of Geophysics and Volcanology, Rome, Italy, (2)INGV National Institute of Geophysics and Volcanology, Rome, Italy, (3)INGV National Institute of Geophysics and Volcanology, Catania, Italy
The frequent flank eruptions occurrence at Mt. Etna lead to a high volcanic hazard that, linked to a population of nearly one million people dwell on its flanks, poses a high volcanic risk.

In the framework of the project PON SIGMA (Integrated Cloud-Sensor System for Advanced Multirisk Management), we developed a near real-time computer-assisted analysis and probabilistic evaluations that provide the identification of the areas prone to the highest vent opening hazard. The use of a code such BET_EF (Bayesian Event Tree_Eruption Forecasting) provide us a long-term hazard map mainly based on the past behaviour of the Etna volcano. The near real-time additional seismic and ground deformation data allow the long-term hazard map switches into a short-term future vent opening one. The short-term hazard map was computed starting from the evaluation of deformation field over Etna surface. Analytical inversion of deformation and seismic data is performed to find the parameters of a magmatic source in an elastic, isotropic and homogeneous half-space and forward model is performed to computed the displacement field over Etna surface.

We modelled the final intrusion of the Mount Etna May 2008 eruption that was accompanied by a violent seismic swarm and marked by ground deformation recorded at GPS stations. Results suggest a good accordance between the higher probability area and the real vent occurrence.