GNGTS 2016 - Atti del 35° Convegno Nazionale

272 GNGTS 2016 S essione 1.3 Cataldi R., Mongelli F., Squarci P., Taffi L., Zito G., Calore C.; 1991: Geothermal ranking of Italian territory . Geothermics, 24 , pp. 115-129. Chiocci F.L., De Alteriis G.; 2006: The Ischia debris avalanche: first clear submarine evidence in the Mediterranean of a volcanic island prehistorical collapse . Terra Nova, 18 , pp. 202-209. De Alteriis G., Violante C.; 2009: Catastrophic landslides of Ischia volcanic island (Italy) during prehistory . The Geological Society, London, Special Publications, 322 , pp. 73-104. Della Seta M., Marotta E., Orsi G., De Vita S., Sansivero F., Fredi P.; 2011: Slope instability induced by volcano- tectonics as an additional source of hazard in active volcanic areas: the case of Ischia island (Italy) . Bull. Volcanol. DOI 10.1007/s00445-011-0501-0. Della Seta M., Esposito C., Marmoni G.M., Martino S., Paciello A., Perinelli C., Sottili G.; 2015: Geological constraints for a conceptual evolutionary model of the slope deformations affecting Mt. Nuovo at Ischia (Italy) . Italian Journal of Engineering Geology and Environment, DOI: 10.4408/IJEGE.2015-02.O-02. del Potro R., Hürlimann M.; 2009: The decrease in the shear strength of volcanic materials with argillic hydrothermal alteration, insights from the summit region of Teide stratovolcano, Tenerife . Engineering Geology, 104 , pp. 135– 143. de Vita S., Sansivero F., Orsi G., Marotta E.; 2006: Cyclical slope instability and volcanism related to volcano- tectonism in resurgent calderas: the Ischia island (Italy) case study . Engineering Geology, 86 , pp. 148-165. de Vita S., Sansivero F., Marotta E., Di Vito M.; 2013: Assetto geologico-strutturale ed evoluzione vulcanologica dell’isola. Miscellanea INGV, 18 , pp. 27-32. Di Napoli R., Martorana R., Orsi G., Aiuppa A., Camarda M., De Gregorio S. et al; 2011: The structure of a hydrothermal system from an integrated geochemical, geophysical, and geological approach: The Ischia Island case study . Geochem. Geophys. Geosyst., 12 , Q07017. Frolova J., Ladygin V., Rychagov S., Zukhubaya D.; 2014: Effects of hydrothermal alterations on physical and mechanical properties of rocks in the Kuril–Kamchatka island arc. Engineering Geology, 183, pp. 80–95. Heap M.J., Lavallée Y., Laumann A., Hess K.U., Meredith P.G., Dingwell D.B.; 2012: How tough is tuff in the event of fire? . Geology, 40 , pp. 311–314. Hossain M.A., Wilson M.; 2002: Natural Convection Flow in a Fluid-saturated Porous Medium Enclosed by Non- isothermal Walls with Heat Generation . Int. J. Therm. Sci., 41 , pp. 447–454. John D.A., Sisson T.W., Breit G.N., Rye R.O., Vallance J.W.; 2008: Characteristics, extent and origin of hydrothermal alteration at Mount Rainier Volcano, Cascades Arc, USA: Implications for debris-flow hazards and mineral deposits . Journal of Volcanology and Geothermal Research, 175 , pp 289–314. Lopez D.L., Williams S.N.; 1993: Catastrophic Volcanic Collapse: Relation to Hydrothermal Processes . Science, 20 , pp, 1974-1976. McKenna J.R., Blackwell D.D.; 2004: Numerical modeling of transient Basin and Range extensional geothermal systems . Geothermics, 33 , pp. 457–476. Reid M.E., Sisson T.W., Brien D.L.; 2001: Volcano collapse promoted by hydrothermal alteration and edifice shape, Mount Rainier, Washington . Geology, 29 , 779–782. Reid M.E.; 2004: Massive collapse of volcano edifices triggered by hydrothermal pressurization . Geology, 32 , pp. 373-376. Rittmann A.; 1930: Geologie der Insel Ischia . Z f Vulkanol Erganzungsband, 6 . Tibaldi A., Vezzoli L.; 1998: The space problem of caldera resurgence: an example from Ischia Island, Italy. Geol Rundsch, 87 , pp. 53-66. Role of mechanical erosion in controlling the effusion rate of basaltic eruptions A. Piombo 1 , A. Tallarico 2 , M. Dragoni 1 1 Dipartimento di Fisica e Astronomia, Alma Mater Studiorum - Università di Bologna, Bologna, Italy 2 Dipartimento di Scienze della Terra e Geoambientali, Università degli Studi “Aldo Moro”, Bari, Italy Observations show that the effusion rate of magma has a typical dependence on time in basaltic eruptions (e.g., Wadge, 1981). In many of these, the effusion rate curves show first a period of increasing and later a ecreasing phase from a maximum value. The effusion rate increases from initially low values during a time of minutes or hours and decreases gradually toward the end of the eruption.