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The zonation presented in this study has been developed with the aim of applying it as a branch of the logic tree that will be used for the new Italian seismic hazard map, presently in preparation according to the approach of seismotectonic probabilism. With respect to the zonation used for the present official seismic hazard map of Italy, the zonation proposed here considers narrower sources and is based on new and updated seismological data. In particular, some new seismogenic zones are proposed here, introducing areas that were not considered seismogenic until now (e.g., the narrow sources characterised by the presence of transform faults which are almost normal to the trend of the northern Apennines). The preliminary seismic hazard estimates produced with this new zonation aim to identify possible problems that the zonation introduces in the seismicity characterization of the seismogenic zones. As the present seismic hazard assessment was computed by considering a different attenuation model with respect to the one applied for the previous national seismic hazard maps, a re-elaboration of the most recent map referring to Italy has been developed: the comparison of the two maps is a good indicator of the areas where additional seismological investigation is needed to support the zonation presented here. In particular, some zones are not adequately documented with regard to seismicity and a different computation of the seismicity rates is suggested.

The geological genesis, evolution and depositional settings of the Mediterranean Sea have been studied for decades by the scientific community which, for some aspects, combines research with the Petroleum Industry to enhance hydrocarbon exploration. It is in these circumstances that the geophysical study hereafter described was conceived. Two research bodies and a multi-client geophysical company have been involved in this project: the Department of Mathematics and Geosciences of the University of Trieste (DMG), the Italian National Institute of Oceanography and Experimental Geophysics (OGS) and TGS Geophysical Company ASA. The paper presents a geophysical analysis, based on interpretation of ten 2D multichannel seismic reflection profiles located in the Eastern Sardo-Provençal basin of the North-Western Mediterranean crossing domains from the outer West Sardinian shelf to the deep basin (Fig.1A,B). The post-stack time migrated lines have a total length of 1545 km and cover an area of about 35.000 km2. The profiles belong to three distinct datasets (WMR, WS, CROP, location on Fig.1A) recorded by different geophysical projects, each of them using specific acquisition parameters. The five WMR (West Mediterranean Regional) profiles were provided by TGS. The three WS (West Sardinia) profiles were acquired by their owner OGS. The two CROP (CROsta Profonda) lines, provided by the DMG, were originally sponsored by AGIP-ENI, CNR & ENEL. The presence of the Messinian rock salt, that within a sedimentary sequence produces halokinesis and scatters most of the acoustic energy, suggested the reprocessing in time domain of a part of a CROP seismic profile in order to improve the imaging of those reflections that are strongly deformed or masked. To enhance image accuracy assessing size and location of geological structures beneath the Messinian salt, a pre-stack depth migration (PSDM) was executed using the Kirchhoff algorithm. The processing outcomes were useful not only to enhance and better define the entire seismic interpretation on the available datasets, but also allowed the evaluation of the peculiar lithologic/stratigraphic conditions of the basin. The integration of the three datasets gave better coverage of the study area and supplied complementary information thanks to different resolutions. On the whole, the work presented hereafter aimed at better knowledge of the depositional history, starting from the Messinian Age, of the North-Western Mediterranean basin.

COST-ANR MEDSALT Symposium, 24-28 October 2016, Palermo, Italy.-- 1 page, This study is based on multibeam bathymetry and multi-channel seismic reflection data collected during Eurofleets R/V OGS Explora, Cruise No. E12 (SALTFLU), Valencia (Spain) 22/06 - 04/07/2012. Modelling of overpressure evoltion is based on the resulting stratigraphy. The study area encompasses proposed drill sites BAL-02 and BAL-02 of IODP pre-proposal 857B-Pre, Deep-Sea Records of the Messinian Salinity Crisis (DREAM), proposed by J. Lofi et al in 2015. We identify four types of salt-induced abyssal plain sediment deformation structures: (1) a belt of elongated abyssal plain seahills thought to be the attenuated surface expression of salt rollers either produced by reactivated right strike slip faults synthetic to the master fault of the EBE or by differential compaction above such faults; (2) anastomosing knolls in the Menorca Fan area thought to be the product of subsurface salt deformation and gliding triggered by differential sedimentary load; (3) abyssal knolls and seahills spread in the entire abyssal plain across the basin thought to be the product of subsurface salt anticlines and pillows in a relatively more evolved stage of basin evolution affected by basement faulting, perhaps northward propagation of the shortening affecting the Algerian margin; and (4) a small flat topped circular mound in the middle of the abyssal plain interpreted as a mud volcano extruding sediments and fluids of likely pre-Messinian origin. The structures suggest that the crustal transition, not imaged in the seismic data due to intense deformation does not correspond to the Emile Baudot Escarpment (the present day continental tectonically driven continental slope). Rather it is located farther offshore in the deep basin, approximately where intense halokinesis occurs in the abyssal plain, marking the edge of the deep Messinian basin filled with kilometer-thick evaporites. Messinian marginal basins, therefore, are presently located also below the abyssal plain, at the floor of the Emile Baudot Esacarpment. Evidence for sub-salt overpressure is provided by pearchment structures in the deep Messinian basin. A compaction disequilibrium modeling exercise demonstrates that the high sedimentation rate of the thick evaporitic succession in the deep Messinian basin, may indeed generate considerable overpressure, persisting today (overpressure coefficient up to 0.8). However, the reduced evaporite thickness in the marginal basins reduces considerably the likelihood of sub-salt overpressure (overpressure coefficient up to 0.2). Therefore, we conclude that marginal basins belong to different geological domains compared to the deep basin, being the difference given by different crustal structure, evaporite thickness, in some cases evaporite composition (absence of halite layer), and pore pressure regime below and within the evaporitic formations. An upward pore water expulsion system is inferred through the Plio-Quaternary sedimentary cover induced by gypsum dehydration to anhydrite

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