Towards an Automatic Monitoring System of Infrasonic Events at Mt. Etna: Strategies for Source Location and Modeling

Active volcanoes characterized by open conduit conditions generate sonic and infrasonic signals, whose investigation
provides useful information for both monitoring purposes and
studying the dynamics of explosive processes. In this work, we
discuss the automatic procedures implemented for a real-time application to the data acquired by a permanent network of five
infrasound stations running at Mt. Etna volcano. The infrasound
signals at Mt. Etna consist in amplitude transients, called infrasound events. The adopted procedure uses a multi-algorithm
approach for event detection, counting, characterization and location. It is designed for an efficient and accurate processing of
infrasound records provided by single-site and array stations. Moreover, the source mechanism of these events can be investigated
off-line or in near real-time by using three different models: (1) Strombolian bubble; (2) resonating conduit and (3) Helmholtz
resonator. The infrasound waveforms allow us to choose the most suitable model, to get quantitative information about the source and
to follow the time evolution of the source parameters.