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High-hazard volcanoes forming islands, often located within territorial water of several European countries, are a favoured tourist destination, a factor that increases the risk. Consequently, the knowledge of volcanic dynamics through time are crucial for risk assessment and mitigation in coastal areas. Gas vents, black smokers, chimneys and any other form of gas emissions are directly connected to the dynamic behaviour of volcanoes, accordingly, intensity variation of gas-released in hydrothermal systems would provide clues on volcanic activity changes, monitoring of which can be crucial for eruption forecasting. In this study we explored the possibility of detecting any submarine volcanic activity from satellite synthetic aperture radar (SAR) images part of the Cosmo-SkyMed mission operated by the Italian Space Agency. Three test sites have been analysed: 1) the hydrothermal system offshore Nea Kameni and Palea Kameni that are part of the Santorini volcanic group (Aegean Sea); 2) the intense and stationary submarine vents within the Paleochori Bay south to Milos Is. (Aegean Sea); and 3) the Panarea hydrothermal system including the Basiluzzo's "smoking land" (South East Tyrrhenian Sea). Visual analysis of all StripMap HIMAGEs, integrated with the wind model maps (produced by ECMWF ERA5), acquired over the selected sites since 2007 have not allowed the detection of any features associable with gas-sea surface interaction, for all the analysed sites. Instead, Radar Cross Section measurements, performed by internally-developed software, revealed an increased averaged reflectivity over the areas interested by the submarine gas emissions respect to similar sites. Particularly in Nea Kameni and Palea Kameni bays the difference is of 0.233 dB and in Paleochori Bay it is of 0.808 dB. The Normalized Radar Cross Section (NRCS) in Panarea and Basiluzzo was practically not different from nearby sites, here the average difference in reflectivity is close to zero (-0.002 dB). Results give confirmation that only intense and continuous emissions of gas can be detected by Satellite radar. Indeed, sites of Panarea/Basiluzzo and even Santorini are not suitable for this kind of monitoring, at least in the current status, while in Paleochori Bay the vents are continuous and enough intense to create a perturbation of sea surface reflectivity to be recorded by Satellite radar. Amongst all investigated sites Paleochori Bay is the most suitable one for future combined Satellite acquisition and fieldwork survey with underwater systems as ROV, which can give additional valuable elements to the high-risk submarine volcanic systems assessment and to the monitoring protocol definition.

Congresso congiunto Società Geologica Italiana (SGI) - Società Italiana di Mineralogia e Petrologia (SIMP), Geosciences for the environment, natural hazards and cultural heritage, 12-14 September 2018, Catania.-- 1 page, The Tyrrhenian back-arc basin is a Neogenic basin that opened in response to the E-SE-ward retreat of the subducting Ionian slab under the Apennine chain. To date a large bibliography is available for this basin (Moeller et al., 2014), but un updated morpho-structural map which takes into account the latest multibeam and multichannel seismic data sets is still lacking. Indeed, the structural maps of the entire Tyrrhenian date back to ‘80/’90. In this work, we present a new morpho-tectonic map of the entire Tyrrhenian basin, from slopes to abyssal plains. This map results from the analysis of 65 multichannel seismic profiles, several sparker profiles and 200-m-grid cell size bathymetry data. All data were georeferenced and interpreted together using the kingdom package (HIS Markit). In detail, the data sets used are composed by the: CROP profiles acquired in the ’90; MS profiles acquired by the OGS during the ’60/’80 (http://snap.ogs.trieste.it/); SITHERE profiles acquired for the site survey of IODP leg 107; MEDOC profiles acquired in 2010; and ISTEGE profiles acquired in the 2010. IODP/DSDP wells (Leg 107 and 42A) and crustal velocity information (Prada et al., 2014, 2015; 2018) were used for the seismo-stratigraphic calibration allowing the mapping of three main units: pre-Messinian; Messinian including evaporites; and Plio-Quaternary. This information allowed to constrain the age of faults activity. Our work results highlight a basin dominated by extension locally overprinted by compression or by transcurrent-motion fault systems. In the western Tyrrhenian, the extension was mostly accommodated by large listric faults forming deep and elongated sedimentary basins. In its eastern (Campania) and southern (Sicily-Calabria) margins the stretching was mainly accomplished through normal faults forming irregular and smaller basins. Furthermore, the central Magnaghi/Vavilov abyssal plain is confined by normal faults that bound the magmatic crust and exhumed mantle rocks (Prada et al., 2016) to continental blocks of the Sardinia-Campania conjugate margins. The Marsili abyssal plain instead is surrounded by fewer, not well expressed, normal faults and, to north and to south, by lithospheric faults (STEP fault)

Congresso congiunto Società Geologica Italiana (SGI) - Società Italiana di Mineralogia e Petrologia (SIMP), Geosciences for the environment, natural hazards and cultural heritage, 12-14 September 2018, Catania.-- 1 page, The main object of the Proposal 927-pre: “ TyrrhenIan Magmatism & Mantle Exhumation” (TIME) is the understanding of the relationship between the exhumed mantle rocks and the overlying basalts sampled in the Tyrrhenian Basin during the previous ODP Leg 107 (Kastens et al 1988).The scientific objectives of the proposal include studying the kinematics of the opening, the nature and timing of associated magmatism and the geochemistry and deformation of the exhumed mantle section.The proposal resulted from the outcome of the MagellanPlus Workshop “TyrrhenIan Magmatism & Mantle Exhumation” (TIME) sponsored by IODP and ECORD. The workshop was held in the Institute of Marine Science (ISMAR) of the National Council of the Italian Research (CNR) in Bologna on June 5-7, 2017. The proposal 927-pre was submitted on October. 2017 and received the recommendation for the development into a full proposal by the IODP STEP Panel on February 2018.The database used to conceive the drilling project is possibly one of the best available from a rifted basin. The basement of the Tyrrhenian basin has been dredged at highs and drilled in several campaigns, and the stratigraphy is reasonably well known from three previous drilling expeditions, DSDP leg 13, DSPD leg 42 and the ODP leg 107 It is available a full-coverage, high-resolution, multibeam bathymetry of the basin as well as a large data set of vintage and modern 2D MCS reflection profiles and seven regional wide-angle seismic profiles crossing the main geological domains (Moeller et al 2014; Prada et al 2016, 2018)

The Catanzaro Trough is a Neogene-Quaternary basin developed between the Serre and the Sila Massif, filled by up to 2000 m of Upper Miocene to Quaternary sedimentary succession, belonging to the central Calabrian Arc and extended from offshore, Sant’Eufemia Basin (SE Tyrrhenian Sea), to the onshore, Catanzaro Basin. By joining on land geo-structural with marine geophysical data, we performed a detailed analysis of processes that during last 5 My have controlled the evolution of western portion of the Catanzaro Trough. The fieldwork study, focused on the onshore area, has allowed to acquire more than 700 fault planes, classified on the base of kinematics and fault directions, whereas the geophysical data (sub-bottom, multi- and mono-channel seismic profiles), coming from some scientific cruises within the Sant’Eufemia Gulf (SE Tyrrhenian Sea), gave us the opportunity to reconstruct the tectono-stratigraphic evolution of the offshore area. The combination amongst abrupt sea level changes, transpressional and trans/extensional tectonics and back-arc Tyrrhenian subsidence during SE-drifting of Calabrian Arc controlled sedimentary basin hosted by the Catanzaro Trough, as the result we have recognized three tectonic events formed in the Upper Miocene- Zanclean, Piacezian-Lower Pleistocene, and Middle-Upper Pleistocene. The data analysis provide information about stratigraphy and tectonics in the strata and also give some indication of the tectono-stratigraphic architecture. Sedimentary basin, in fact, looks to be mainly controlled by the activity of NW–SE and NE–SW oriented fault systems. The NW-SE oriented faults showing strike slip and oblique kinematics can be considered responsible for the opening of a WNW–ESE paleo-strait connecting the Tyrrhenian Sea with the Ionian Sea during multi-phases tectonics that have acted in the study area since Miocene. The integrated geo-structural and geophysical data show a change from left-lateral to right-lateral kinematics during Piacezian-Lower Pleistocene, as the result of a change of the stress field. Since Middle Pleistocene, the study area experienced an extensional phase, WNWESE oriented, controlled mainly by NE-SW and subordinately N-S oriented normal faults, which split obliquely the western Catanzaro Trough, producing up-faulted and downfaulted blocks, arranged as graben-type systems, extending from onshore to offshore area. In agreement with and Jacques et al., (2001) and Presti et al., (2013), the NE-SW and NS trend normal faults play a relevant role as part of recent seismotectonic processes controlling the Late Quaternary geodynamic of the central Calabrian Arc, representing the source of the main destructive earthquakes occurred in the area. Thanks to these multidisciplinary approach we are able to provide a more reliable and detailed structural frame of the central Calabria segment, providing new elements about recent activity of faults, and giving a further contribution for the seismogenetic potential assessment of an area historically considered with the highest earthquake and tsunami risk throughout Italy. Scuola di Dottorato "Archimede" in Scienze, Comunicazione e Tecnololgie, indirizzo Scienze della Terra, Ciclo XXVII, a.a. 2015-2016 Università della Calabria

The earthquake (Mw 7) that struck western Calabria (southern Italy) on 8 September 1905 profoundly struck a broad region, causing 557 deaths, injuring more than 2000 people, and leaving about 300,000 people homeless. Historical documents also reported a tsunami, although not devastating, for which effects were observed both along the coast and offshore. For all the damage it caused, this event was much studied but not fully explained. Literature source models for the 1905 earthquake are numerous and diverse, in fault geometry, location, and even associated magnitude. They also differ in nature, because these solutions are either field-based or derived from tsunami modeling and macroseismic data inversion. Above all, few or none of the previously published source models appear to be fully compatible with the damage pattern caused by this earthquake. To contribute to the identification of the seismogenic source of this destructive event, we computed a series of ground-shaking scenarios based on the different fault-source models that various authors associated with this event. The only documented data available that are suitable for our comparative purposes are the macroseismic intensities associated with localities affected by the event. Our results show that shaking scenarios for two out of seven literature source models are compatible with the damage distribution caused by the 1905 earthquake. The different parameters and boundary conditions constraining these two solutions suggest that either seismogenic source should include further complexities. Alternatively, because these two sources are antithetic and partially form a graben, they might have kinematically interacted, if passively, on 8 September 1905. Also, our critical analysis attempts to take site effects into account, at least qualitatively, allowing a more robust evaluation of damage distribution against numerical models.