GNGTS 2013 - Atti del 32° Convegno Nazionale

In particular, the main morphological and structural features on the submerged portions of volcanic edifices, such as Panarea and Stromboli in the Aeolian Arc (Sicily, Southern Italy) have been identified through high resolution seismic profiles and seismic tomography in the south-eastern Tyrrhenian sea (Gabbianelli et al. , 1996; Castellano et al. , 2008). Conclusions. The Ischia island is encircled by several lava outcrops, interpreted as megadykes, whose formation seems to be linked to the calderic nature of the volcanic complex. These megadykes are located in correspondence to the Punta Cornacchia, Punta dello Zaro, S. Angelo and Punta del Soccorso promontories (Rittmann, 1930). Debris avalanche detachments develop between these volcanic lineaments, both in the southern and in northern sides of the island. This is not verified for the eastern side. Here, the lateral collapses occur within morphological protrusions, coincident with lava outcrops. The debris deposits systematically originate inside the A and C morphological units, whereas the marine deposits are detected within the C and D physiographic units. Slow mass movements and borders of detachments are detected only into the D unit area. We have interpreted this evidence as it follows. The A morphological unit is mainly related to the rising up of the Epomeo block. The B morphological unit is related to the presence of the upper shelf, strongly eroded at its upper border. The C morphological unit individuates the upper scarp, which is to be retained as tectonically- controlled, since it exhibits an average slope value with respect to the expected one and a strong gradient at its foot. Finally, the D morphological unit outlines the lower escarpment, which is characterized by the presence of hemipelagic drapes. References Acocella V. and Funiciello R.; 1999: The interaction between regional and local tectonics during resurgent doming: the case of island of Ischia, Italy : Journ. Volcanol. Geoth. Res., 88, pp. 109-123. Acocella V., Funiciello R. and Lombardi S.; 1997: Active tectonics and resurgence in Ischia island (southern Italy) . Il Quaternario, 10, pp. 427-432. Acocella V., Funiciello R., Marotta E., Orsi G. and De Vita S.; 2004: The role of extensional structures on experimental caldera and resurgence. Journ. Volcanol. Geoth. Res., 129, pp. 199-217. Aiello G., Budillon F., Cristofalo G., D’Argenio B., de Alteriis G., De Lauro M., Ferraro L., Marsella E., Pelosi N., Sacchi M. and Tonielli R.; 2001: Marine geology and morpho-bathymetry in the Bay of Naples . In: Faranda F.M., Guglielmo L. and Spezie G. (Eds.) Structures and Processes of the Mediterranean Ecosystems , Springer-Verlag Italy, Chapter 1, pp. 1-8. Aiello G., Marsella E. and Passaro S.; 2009a: Submarine instability processes on the continental slopes off the Campania Region (Southern Tyrrhenian sea, Italy): the case history of Ischia island (Naples Bay). Boll. Geof. Teor. Appl., 50 (2), pp. 193-207. Aiello G., Budillon F., Conforti A., D’Argenio B., Putignano M.L. and Toccaceli R.M.; 2009b: Progetto per la realizzazione di cartografia geologica marina secondo le modalità CARG. Note illustrative alla cartografia geologica marina. Foglio geologico n. 464 “Ischia”. Preprints, 25 May 2009, III SAL Geologia Marina, IAMC, Istituto per l’Ambiente Marino Costiero, Geomare Sud, CNR, Napoli. Aiello G., Marsella E. and Passaro S.; 2012a: Stratigraphic and structural setting of the Ischia volcanic complex (Naples Bay, southern Italy) revealed by submarine seismic reflection data. Rend. Lincei, 23 (4), pp. 387-408. Aiello G., Giordano L., Marsella E. and Passaro S.; (2012b): Seismic stratigraphy and marine magnetics of the Naples Bay (Southern Tyrrhenian sea, Italy): the onset of new technologies in marine data acquisition, processing and interpretation. In: Elitok O. (Ed.) Stratigraphic Analysis of Layered Deposits , Intech, Chapter 2, pp. 21-60. Amante C. and Eakins B.W; 2008: ETOPO1 Arc-Minute Global Relief Model: Procedures, Data Sources and Analysis. 1 st Edition, NOOA, National Geophysical Data Center, Boulder, Colorado. Barra D., Cinque A., Italiano A. and Scorziello R. (1992): Il Pleistocene superiore marino di Ischia; paleoecologia e rapporti con l’evoluzione tettonica recente. Studi Geologici Camerti, Suppl. 1, pp. 231-243. Bruno P.P.G., de Alteriis G. And Florio G.; (2002): The western undersea section of the Ischia volcanic complex (Italy, southern Tyrrhenian sea) inferred from marine geophysical data. Geophys. Res. Lett., 29 (9), 1343, doi: 10.1029/2001GL013904. Buonasorte G., Ciccacci S., De Rita D., Fredi P. and Lupia Palmieri E.; (1993): Some relations between morphological characteristics and geological structure in the Vulsini Volcanic Complex. Zeitsch fur Geomorph., Suppl. BD 82, pp. 59-71. Calcaterra D., De Riso R., Evangelista R., Nicotera A., Santo A. and Scotto di Santolo A.; (2003): Slope instabilities in the pyroclastic deposits of the Phlegrean district and the carbonate Apennine (Campania, Italy). Int. Workshop on Occurrence and Mechanisms in Natural Slopes and Earthfills, IW Flows 2003, Sorrento, May 14-16, 2003. 230 GNGTS 2013 S essione 1.3