GNGTS 2019 - Atti del 38° Convegno Nazionale

194 GNGTS 2019 S essione 1.3 TWO DECADES OF GEODETIC AND PETROLOGICAL OBSERVATIONS AT MT. ETNA VOLCANO (ITALY) M. Palano 1 , M. Viccaro 1,2 1 Istituto Nazionale di Geofisica e Vulcanologia, sezione di Catania - Osservatorio Etneo, Catania, Italy 2 Università degli Studi di Catania, Dipartimento di Scienze Biologiche, Geologiche e Ambientali, Sezione di Scienze della Terra, Catania, Italy Introduction. Mt. Etna is an open-vent Quaternary basaltic stratovolcano located on the eastern coast of Sicily (Fig. 1). It built up over the past 0.6-0.5 Ma at the front of the Apennine- Maghrebian thrust belt in the complex geodynamic setting of the Neogene-Quaternary Nubia- Eurasia convergence (e.g. Palano et al. , 2012 and references therein). In the last two decades, Mt. Etna’s volcanic activity has been characterized by more than 100 paroxysmal events (from moderate to intense and impulsive explosive activity, coupled sometime to voluminous lava flows) as well as by some large eruptive events (e.g., 2001, 2002- 03, 2004-05, 2006, 2008) involving the upper sector of the northern and southern flanks of the volcano, along with the summit craters. Therefore, based on a dataset of continuous GPS observation spanning the January 2001 - December 2018 interval, we propose a comprehensive picture of the deformation patterns occurring at Mt. Etna volcano. Major-trace elements plus Sr-Nd isotopic compositions (and Pb-Hf-O where available) for the whole rock, together with interpretations based on the crystal records in products coming from the 2001-2018 eruptive activity have been also integrated to the deformation history. The huge amount of available data furnishes all together an unprecedent reconstruction of the plumbing system dynamics at the volcano. GPS Network, data processing andmodelling. Routine use of GPS to monitor deformation of Mt. Etna volcano started in the summer of 1988 whit the surveying of a network of 18 benchmarks (Briole et al. , 1992). The setting up of a continuous GPS network began inNovember 2000 reaching a configuration of 13 stations in late summer of 2001. The network geometry Fig. 1 - Simplified tectonic map of Mt. Etna and its eastern off-shore. GPS stations covering Mt. Etna volcano are reported as colored points. Abbreviations are as follows: PF, Pernicana fault; TFS, Timpe Fault system; SVF, Santa Venerina fault; STF, Santa Tecla fault; AF, Acitrezza fault; TF, Trecastagni fault; MTF, Mascalucia-Tremestieri fault; ESEL, ESE lineament. Upper Inset: sketch map of eastern Sicily; AMC, Apennine-Maghrebian chain; HF, Hyblean Foreland; GCF, Gela-Catania Foredeep. Lower inset: zoom of volcano summit craters (Bocca Nuova, BN; Voragine, VOR; North-East Crater, NEC; South-East Crater, SEC; New South-East Crater, NSEC).