GNGTS 2017 - 36° Convegno Nazionale

GNGTS 2017 S essione 1.3 189 at shallow depth, forcing the fragmentation of the high viscous magma and contributing to increase the eruptive explosivity and MDR. Contamination timescale has been constrained applying the crystal size distribution (CSD) theory on clinopyroxene microlites (which are formed in syn-eruptive phase). The crystallization time obtained ranges from hours to days, in agreement with clinopyroxene texture displaying elongate, tabular and swallowtail morphologies, that are an evidence of rapid crystallization. Conclusions. In conclusion, our 3D-textural and Sr- and Nd- isotopic data demonstrate that magma/limestone interaction can be a fast syn-eruptive process developed during magma withdrawal and ascent in volcanic conduit that can contribute to amplify the intensity of eruptions. This is especially important for mafic-intermediate active volcanic systems developed within a carbonate substrate, that are widespread in several tectonic settings. References Balcone-Boissard H., Boudon G., Cioni R., D.Webster J., Zdanowicz G., Orsi G. and Civetta L.; 2016: Chlorine as a geobarometer for alkaline magmas: Evidence from a systematic study of the eruptions of Mount Somma - Vesuvius. Sci. Rep., 6, 21726. Bertagnini A., Landi P., Rosi M. and Vigliargio A.; 1998: The Pomici di Base plinian eruption of Somma-Vesuvius. J. Volcanol. Geotherm. Res., 83, 219–239. Blythe L.S., Deegan F.M., Freda C., Jolis E.M., Masotta M., Misiti V., Taddeucci J. and Troll V.R.; 2015: CO 2 bubble generation and migration during magma–carbonate interaction. Contrib. Mineral. Petrol., 169 (4), 1–16, doi:10.1007/s00410-015-1137-4. Deegan F.M., Troll V.R., Freda C., Misiti V. and Chadwick J.P.; 2011: Fast and furious: crustal CO 2 release at Merapi volcano, Indonesia. Geol. Today, 27, 57-58. De Lorenzo S., Di Renzo V., Civetta L., D’Antonio M. and Gasparini P.; 2006: Thermal model of the Vesuvius magma chamber. Geophys. Res. Lett., 33, L17302. Landi P., Bertagnini A. and Rosi M.; 1999: Chemical zoning and crystallization mechanisms in the magma chamber of the Pomici di Base plinian eruption of Somma-Vesuvius (Italy). Contrib. Mineral. Petrol., 135, 179–197. Masotta M., Mollo S., Freda C., Gaeta M. and Moore G.; 2013: Clinopyroxene–liquid thermometers and barometers specific to alkaline differentiated magmas. Contrib. to Mineral. and Petrol., 166, 1545–1561. Toramaru A.; 2006: BND (bubble number density) decompression rate meter for explosive volcanic eruptions. J. Volcanol. Geotherm. Res., 154, 303–316. The December 2015 and May 2016 eruptions at Mt. Etna: insight on volcano plumbing system structure and geometry by a multidisciplinary approach A. Cannata 1,2 , G. Di Grazia 2 , M. Giuffrida 3 , S. Gresta 3 , M. Palano 2 , M. Sciotto 2 , M. Viccaro 3,2 , F. Zuccarello 3 1 Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, Italy 2 2Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio Etneo, Catania, Italy 3 Dipartimento di Scienze Biologiche, Geologiche e Ambientali, Università degli Studi, Catania, Italy Introduction. The enhancement of our knowledge on volcano plumbing system structure and geometry, as well as on magma dynamics and timescales, requires a multidisciplinary approach (e.g. Pallister and McNutt, 2015). Mt. Etna volcano is monitored by amultiparametric permanent network (Fig. 1), continuously producing streaming of variegated data (i.e. GPS, seismic, infrasonic, tiltmetric, video, thermal data and so on). Therefore, it can be considered a perfect natural laboratory to perform multidisciplinary studies (e.g. Cannata et al. , 2015; Viccaro et al. , 2016). In the period January 2011 - December 2014, the New South-East Crater (NSEC) produced more than 50 paroxysmal episodes, while the South-East Crater (SEC), Bocca Nuova (BN) and North-East Cater (NEC),