GNGTS 2024 - Atti del 42° Convegno Nazionale

Session 1.2 GNGTS 2024 Automated detecton, characterizaton, and localizaton of Very Long-Period seismic events specifcally designed for volcanic monitoring applicatons on Stromboli Island. S. Gammaldi, D. Delle Donne, P. Cantello, W. De Cesare, A. M. Esposito, R. Peluso, M. Orazi Isttuto Nazionale di Geofsica e Vulcanologia (INGV), Osservatorio Vesuviano, Sezione di Napoli. Real-tme applicatons in seismology have become essental for actvely monitoring and surveilling volcanoes. They serve as valuable tools for promptly identfying volcanic unrest. In open-vent actve volcanoes, the detecton of Very Long Period (VLP) seismicity, typically associated with mild and persistent explosive actvity, holds paramount signifcance in volcano monitoring. Variatons in the occurrence rate and magnitude of VLP seismicity may indicate an impending phase of unrest. This study introduces a novel method for the automatc real-tme detecton and characterizaton of VLP seismicity at the Stromboli actve volcano in Italy. The detecton algorithm relies on Three-Component Amplitude (TCA), derived from waveform polarizaton and spectral analysis of contnuous recordings. It furnishes crucial informaton such as the tme of detecton, azimuth, incidence, amplitude, and frequency of the identfed VLP. The automatcally detected amplitude is then presented as peak-to-peak and root mean square amplitude, facilitatng the automated amplitude localizaton of VLP. The VLP detectons and characterizatons obtained through our automatc detecton algorithm are compared with those derived from manual and automatc inspectons of the seismic record, as well as with VLP tme histories from existng published datasets. The comparison reveals that the VLP detecton tme series generated by the automatc algorithm efectvely mirrors fuctuatons in VLP actvity, as manually identfed by operators over an approximately 20-year period. This validaton allows for the integraton of the automatc algorithm into the real-tme processing framework employed at Stromboli for volcano surveillance. Corresponding author: sergio.gammaldi@ingv.it