GNGTS 2016 - Atti del 35° Convegno Nazionale

GNGTS 2016 S essione 1.3 249 A guide to tectonic evolution. In Hudson, M.R., and Grauch, V.J.S., eds., New Perspectives on Rio Grande Rift Basins: From Tectonics to Groundwater: Geological Society of America Special Paper, 494, 21–45, doi:10.1130 /2013.2494(02). Brown R., Civetta L., Arienzo I., D’Antonio M., Moretti R., Orsi G., Tomlinson E.L., Albert P.G., Menzies M., 2014. Assembly, evolution and disruption of a magmatic plumbing system before and after a cataclysmic caldera- collapse eruption at Ischia volcano (Italy). Contrib. Mineral. Petrol., 168, 1035, DOI:10.1007/s00410-014-1035- 1. Carlino S., Somma R., Troise C., De Natale G., 2012. The geothermal exploration of Campanian volcanoes: Historical review and future development. Renewable and Sustainable Energy Reviews, 16, 1004–1030. D’Antonio M., 2011. Lithology of the basement underlying the Campi Flegrei caldera: Volcanological and petrological constraints. Journal of Volcanology and Geothermal Research 200, 91–98. Fedele, F.G., Giaccio, B., Isaia, R., Orsi, G., 2003. The Campanian Ignimbrite Eruption, Heinrich Event 4, and Palaeolithic Change in Europe: a High-Resolution Investigation. In: Robock, A., Oppenheimer, C. (Eds.), Volcanism and the Earth’s Atmosphere: Am. Geophys. Un., Geophys. Monogr., 139, 301–325. Fedi, M., Quarta, T., 1998. Wavelet analysis for the regional-residual and local separation of potential field anomalies. Geophysical Prospecting 46, 507–525. Ferrucci F., Gaudiosi G., Pino N.A., Luongo G., Hirn A., Mirabile L., 2989. Seismic detection of a major Moho uphaeval beneath the Campania Volcanic Area. Geophysical Research Letters, 16 (11), 1317-1320. Lipman P.W., Bachmann O., 2015. Ignimbrites to batholiths: Integrating perspectives from geological, geophysical, and geochronological data. Geosphere; June 2015; 11 (3), 705–743; doi:10.1130/GES01091.1. Martel C., Champallier R., Prouteau G., Pichavant M., Arbaret L., Balcone-Boissard H., Boudon G., Boivin P., Bourdier J.L., Scaillet B., 2013. Trachyte Phase Relations And Implication For Magma Storage Conditions In The Chaine Des Puys (French Massif Central). Journal Of Petrology, 54 (6), 1071-1107. Doi:10.1093/Petrology/ Egt006. Niu, Y., Batiza, R., 1991. DENSCAL: a program for calculating densities of silicate melts and mantle minerals as a function of pressure, temperature, and composition in melting range. Computer Geosci. 17 (5), 679-687. Orsi, G., D’Antonio, M., de Vita, S., Gallo, G., 1992. The Neapolitan Yellow Tuff, a largemagnitude trachytic phreatoplinian eruption: eruptive dynamics, magma withdrawal and caldera collapse. J. Volcanol. Geotherm. Res., 53, 275–287. Santacroce, R., Cioni, R., Marianelli, P., Sbrana, A., Sulpizio, R., Zanchetta, G., Donahue, D.J. & Joron, J.L., 2008. Age and whole rock-glass compositions of proximal pyroclastics from the major explosive eruptions of Somma- Vesuvius: a review as a tool for distal tephrostratigraphy. J. Volcanol. Geotherm. Res. 177, 1–18. Zollo, A., Maercklin, N., Vassallo, M., Dello Iacono, D., Virieux, J. & Gasparini P., 2008. Seismic reflections reveal a massive melt layer feeding Campi Flegrei caldera. Geophysical Research Letters, 35, L12306. Magma degassing, hydrothermal systems and volcanic unrest: the case of Campi Flegrei (Italy) G. Chiodini 1 , A. Paonita 2 , A. Aiuppa 3 , S. Caliro 4 , C. Cardellini 5 , A. Costa 1 , P. De Martino 4 , A. Mangiacapra 4 , F. Quareni 1 , Z. Petrillo 4 1 INGV, sezione di Bologna, Italy 2 INGV, sezione di Palermo, Italy 3 Università di Palermo, Italy 4 INGV, sezione di Napoli, Italy 5 Università di Perugia, Italy An ascending magma batch, upon decompression, selectively releases dissolved volatiles depending on their solubilities so that, while barely soluble CO 2 dominates “deep” degassing, more soluble H 2 O prevails at shallow depths. This selective release of volatiles from magma implies that heat transfer to overlying hydrothermal systems exhibit a non-linear pressure dependence. By applying a gas-melt degassing model, we find that there is a narrow pressure interval (CDP, critical degassing pressure) over which the total amount of separated fluid and of the associated thermal energy steeply increases by more than one order of magnitude.