GNGTS 2019 - Atti del 38° Convegno Nazionale

GNGTS 2019 S essione 1.3 185 Galluzzo D., Nardone L., Carandente A., Buonocunto C., Scarpato G., Marotta E., Milano G., Govoni A., Moretti M. (2019). Le attività del gruppo operativo SISMIKO in occasione del terremoto di Ischia Mw3.9 (Md4.0) del 21 Agosto 2017. Quaderni di Geofisica, in press. Orazi M., Tramelli A., Augusti V., Bellucci Sessa E., Bobbio A., Brandi G., Buonocunto C., Capello M., Carandente A., Caputo A., De Cesare W., Di Lieto B., Esposito A., Galluzzo D., Giannuzzi R., Giudicepietro F., Lo Bascio D., Margheriti L., Marotta E., Martino C., Moretti M., Nardone L., Ricciolino P., Peluso R., Pinto S., Romano P., Scarpato G., Torello V., Castellano M., 2018. La rete sismica di Ischia dell’Osservatorio Vesuviano –INGV: evoluzione, conFig.zione attuale e performance. Proceedings of the 37° GNGTS, 261-265 . Prieto, G. A., Lawrence, J. F., & Beroza, G. C. (2009). Anelastic Earth structure from the coherency of the ambient seismic field. Journal of Geophysical Research: Solid Earth, 114(B7). Strollo R., Nunziata C., Iannotta A., Iannotta D., 2015. The uppermost crust structure of Ischia (southern Italy) from ambient noise Rayleigh waves, Journal of Volcanology and Geothermal Research 297, pag. 39–51. STRATIGRAPHIC AND STRUCTURAL STUDY OF THE OFFSHORE SECTOR OF THE CAMPI FLEGREI CALDERA BASED ON MULTISCALE SEISMIC PROFILES ANALYSIS C. Marino 1 , L. Ferranti 1 , J. Natale 1 , M. Sacchi 2 , L. Steinmann 3 , V. Spiess 3 1 Dipartimento di Scienze della Terra, dell’Ambiente e delle Risorse (DiSTAR), Università “Federico II”, Napoli, Italy 2 Istituto per l’Ambiente Marino Costiero (IAMC), Consiglio Nazionale delle Ricerche (CNR), Napoli, Italy 3 Universität Bremen, GEO Gebäude / Raumnr. Bremen A seismo-stratigraphic and structural analysis of multiscale seismic profiles provided insights into the past ~39 ka deformation of the submerged part of the Campi Flegrei resurgent caldera, off the Pozzuoli Bay (Southern Italy). The Campi Flegrei caldera, located along the Campania margin, is a very high-risk volcanic area and represents a key example of an active resurgent caldera, as proven by ongoing unrest involving ground deformation, seismicity, and hydrothermal activity. The Campi Flegrei volcanic zone has been traditionally interpreted as a nested caldera formed by collapses associated with two main eruptions: the 100-200 km 3 Campania Ignimbrite (CI), ~39 ka BP, which is regarded as Europe’s largest and most devastating eruption of the past 200 ka (Deino et al. , 2004), and the 40 km 3 eruption of the Neapolitan Yellow Tuff (NYT) at ~15 ka BP (Di Vito et al. , 1999). The collapse of the central part of the Campi Flegrei is associated with the eruption of the NYT was followed by discrete phases of intra-caldera volcanic activity and resurgence (Marturano et al. , 2018). Despite the volcanic and tectonic evolution of the onshore part of the caldera has been intensely studied since long, only in recent years the southern part of the caldera presently submerged off the Pozzuoli Bay has been explored using marine geophysical data (Sacchi et al. , 2014; Steinmann et al. , 2016; 2018). Utilizing a multiscale seismic dataset, we investigated the formation and evolution of the Campi Flegrei caldera. The main research topics and preliminary results are shown here as follows: • A detailed study of the depositional architecture of the basin infill highlights a close link between the post-LGM sea level rise and the caldera resurgent dome system. The analysis has revealed the occurrence of transgressive and regressive events both inside and outside (e.g. Procida channel) the caldera, whose stratal pattern provides evidence of control by both the sea-level rise and alternating phases of seafloor uplift and subsidence. • Major structural features were identified and analyzed and include: the caldera ring-faults, the resurgent dome with associated apical extensional faults, and the extra-caldera faults linked to the broader context of Campi Flegrei volcanism and to the regional tectonic setting of the Campanian margin.