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The present‐day tectonic setting of the Eastern Mediterranean Sea results from a long deformation history, characterized by an alternation of extensional and contractional phases: from Mesozoic rifting to Late Cretaceous-present-day compression. This study focused on the tectonic reconstruction of the north-eastern side of the Mediterranean Sea, on a sector located between the Turkish coast and the northern Levantine Basin, using seismic reflection profiles. Previous studies dealt with the recent (Neogene) evolution because they did not have enough depth of investigation to recognize deeper reflections. We used vintage data such as MS and Strakhov surveys to analyze the deeper part of the area. We interpreted and depth-converted these seismic data, and we developed a sequential restoration to reconstruct the stratigraphic and structural evolution of the study area. In general, from north to south, we recognize the Cilicia Basin: a piggy-back basin bordered to the south by the offshore continuation of the Kyrenia Range. The Kyrenia Range is a positive flower structure generated during a transpressional phase because of the rotation of the Arabic plate. Southward, a secondary contractional system with an onlapping wedge is present in the area between the Kyrenia Range and another prominent ridge, i.e. the Larnaca Ridge. In the southern part, the same transpressional phase that generated the Kyrenia Range led to a positive inversion of an ancient extensional system, i.e. the Latakia Ridge. Beyond these positive flowers, the Levantine Basin is affected by extensional structures showing weak positive reactivation, including halokinetic features. In summary, we found that the inherited extensional structures strongly impacted the following contractional ones affecting both their geometry and their kinematics.

The presence of fluids in the sediments of the Gulf of Trieste (Northern Adriatic) produces surface occurrences that have been identified by high resolution seismic data. In particular, south-west of Grado, six sites have been pinpointed with evidence of accumulation of fluids within the sediment, dispersion of fluids in the water column, and presence on the sea bottom of rocky outcrops whose genesis is assumed to be linked to the precipitation of calcium carbonate methane-derived.

Several studies have described the geological setting of the Kvarner area (Northern Adriatic Sea) based on the outcropping sedimentary sequences. They are mainly represented by the Adriatic carbonate platform (AdCP) affected by the compressional/ transpressional deformation of the External Dinaric orogen, which produced both thin- and thick-skinned tectonics. In this study, we used an extensive 2D seismic, and well dataset initially acquired for hydrocarbon exploration of the Kvarner area. The 2D seismic lines were calibrated by the wells, which allowed us to reconstruct the connection between the tectonic structures of the offshore and onshore areas. In particular, the continuity of the main SE-Istrian anticlines and the northern Dalmatian Islands has been recognized and depicted by a time structural map of the base of the Plio-Quaternary sequence. These anticlines, originating from the pre-Messinian Dinaric thrust system, were reactivated by the post-Messinian transpressional tectonics, which produced positive flower structures. Between the anticlines, sharp valleys, canyons, and channels crossing the Kvarner offshore area outline two main low structural lineaments. They are partially incised during the Messinian and can be followed in Istria onshore for several kilometers. Messinian and post-Messinian erosional effects were influenced by the morphology of older tectonic structures produced by the Dinaric compressional phase and the more recent transpression. Fluvial-deltaic depositional systems fill the valleys with mainly clinoform geometry. Wells never calibrated this sedimentary sequence. Thus, we hypothesize a Plio-Quaternary or a Late Messinian age, related to the Lago-Mare Formation. The back-trusts seem to have been recently reactivated as strike-slip structure in the Rijeka city area and the Krk island (eastern Kvarner). The AdCP shows a gentle tilting toward the Apennine Chain in the western explored area, whose outermost front is situated more than 80 km to the west. This tilting re- activated older normal faults and is probably enhanced by an uplift of the Istria peninsula.

This study presents an overview of structural and stratigraphic relationships of the northern part of Croatian offshore and Kvarner area. The availability of a large 2D seismic dataset covering the area, integrated by three boreholes and one sonic log allowed a good correlation between sedimentary units and seismic facies highlighted on the profiles. Despite intensive geological and geophysical exploration during the past few decades, there is a lack of published work on seismic facies analysis and structural framework in this area. The present geological understanding in the part of a wider Dinaric and Adriatic area is mostly related to the studies conducted on the onshore (GKSFRJ, 1970 ; Vlahović et al., 2005 ; GKHR, 2009 ; Korbar, 2009 and references therein), or by integration of offshore seismic and well data (Đurasek et al., 1981 ; Prelogović, 1995 ; Grandić et al., 1999, 2001 ; Del Ben, 2002). However, majority of publication deals with southern Croatian (Prtoljan et al., 2007 ; Wrigley et al., 2012) and other with Italian part of Adriatic offshore area (Finetti, 2005 ; Busetti et al., 2010 ; Cazzini et al., 2015). Therefore, this study aims to give a geological meaning to main reflectors and compare them with onshore units by integration of interpreted structural framework. This was achieved by synthetic seismogram generation, while some seismic attributes were used to improve fault detection and better recognition of some deep reflectors, particularly the Top Triassic clastites/base Carbonates.

Despite several offshore data are available, a general model of the central part of the Izmit Gulf is still a challenge and only few measurements have been done on the Hersek peninsula. This area is a key point not only because represents the only onshore segment of the North Anatolian Fault (NAF) within the central part of the Izmit Gulf, but also because the new Istanbul-Izmit highway will cross such gulf in this zone, with a suspension bridge, which will be the second longest bridge of such type in the world. This paper, integrating different analyses and data sets aims verifying at some of the present hypotheses. In particular, we propose the joint interpretation of new seismic reflection profiles from the Hersek Peninsula, as well as geophysical, remote sensing and geological data from the Izmit Gulf (Sea of Marmara, Turkey), close to the epicenter of the 1999, M-w 7.4 Izmit earthquake, to identify shallow-crustal deformations associated with the NAF. Our seismic reflection profiles, which are the first onshore two-components records within the Izmit Gulf, image compressive features that form a structural high cut by the principal deformation zone of the NAF. The observed transpressive stress pattern appears to be the main factor contributing to the physiography of the peninsula, together with the growth northwards of the Yalakdere River deposits. We demonstrate that this pattern is compatible with an 8 degrees bending of the NAF strand. Based on these new data, we propose a kinematic model for the evolution of this structure around the Hersek Peninsula during Holocene, and we test our reconstruction using a finite-elements numerical simulation model of the stress/strain distribution.

We propose the integration of magnetic, electromagnetic (ground- penetrating radar, GPR) and seismic methods to study the inner structure of pre- historic funerary mounds. The combination of techniques allows high-resolution imaging and detection of buried targets and characterization of subsurface materi- als based on magnetic susceptibility, dielectric permittivity, conductivity and seismic velocity/attenuation. The 2012 archaeo-geophysical expedition to Scythian necrop- oleis in Kazakhstan allowed advancement of the integrated procedure through opti- mization of the individual techniques. We improve the results of seismic tomography inversion through an ART algorithm with a relaxation parameter which is progres- sively reduced during the iterative reconstruction process. We use instantaneous at- tributes and spectral decomposition to improve the interpretation of GPR reflection data. The results obtained from the 2012 dataset allow detailed reconstruction of the inner structure of three kurgans (i.e. funerary mounds) with maximum 7 m cen- tral elevation. In particular, localized anomalies related to metallic targets smaller than the GPR and seismic resolution limits are identified from magnetic data after high pass filtering; GPR data allow imaging of inner stratigraphy up to a maxi- mum depth of about 250 cm; seismic tomography maps large traveltime anomalies probably related to funerary chambers at the base of the mound.

In this work we present a comparison between two seismic datasets acquired by the oceanographyc research vessel OGS-Explora through the passive margins of the West Mediterranean sea: the West Sardinia continental margin of the Sardo-Provencal basin (WS10 dataset acquired in 2010) and the South Balearic continental margin of the Algerian basin (SF2012 dataset, acquired in 2012 within SALTFLU project). The West Sardinia margin was originated by the Oligocene-Early Miocene breakup of European plate followed by the drift of the Sardinian block and the southern French margin; the Algero-Balearic basin opened later respect the Balearic basin, dating its oldest oceanic crust 16My following the rift of the Kabylide thrust belt (Muffret et al., 2004 and cited literaure). Although the margins are different in age and geodynamic histories, here we intend to focus on differences and analogies concerning the geological features that characterize the Messinian and Post Messinian period, starting from the availability of already processed and interpreted seismic dataset of Western Sardinia (Geletti et al., 2014) and of processed by OGS and partly interpreted profiles of South Balearic margin. In particular this approach should allow us to correlate the Messinian and Plio-Quaternary units that deposited in the West Mediterranean. The comparison let to make considerations about the seismic facies of the Messinian sedimentary sequence that characterize the basinal domain and the slope of the North Algerian margin; analogies with the seismic facies of the Upper evaporite Unit recognized in the Sardo Provencal basin have been observed, represented by a thick well stratified package of high amplitude reflectors and intercalation of transparent layers. Observation about deformation structures mainly due to salt tectonic activity will be presented, basing on the already identification by Camerlenghi et al., (2009), of different kind of salt-induced abyssal plain sediment deformation. Basing on the fact that there are lack of information in this sector of Western Mediterranean due to the absence of calibrating boreholes, this work could be a starting point to a major comprehension of the distribution of the Messinian Salinity Crisis processes within the basins of the Mediterranean sea.

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.

The MSC, even if it is well documented in the whole Mediterranean Sea by several different seismic markers, is a still open question. The interpretation of the seismic signatures let to distinguish alternated phases of exposure and flooding of the different basins which often result to be hardly correlated to one another. In the Adriatic basin and in the Sicily Channel the Messinian layer, where it is not replaced by an erosional surface, is present as a thin evaporate layer mainly constituted by Gessoso Solfifera formation. The Messinian trilogy has been observed only in the deep Balearic Basin, while in the Ionian and Levantine Basins it shows a mainly salt seismic facies. The presented seismic data aim to contribute to the recognition of the different seismic facies which characterize the different units; their comparison could improve the comprehension of the processes that affected the Messinian events in the Mediterranean region, specially because of the critical lacking of boreholes.

The geological setting of the Central Adriatic Basin is characterized by the presence of several sedimentary features originated during the growing up of the Dinaric and Apennine Chains. The migration of these fronts towards the axis of the Adriatic Sea, determined the Plio-Quaternary clastic sequence (Channel et al., 1979). During the Lower Pliocene, the migration of the Apennine Chain produced the west-ward tilting of the Adriatic foreland, causing a sedimentary wedge and a thickness of sub-horizontal Pliocene deposits, covered by the Quaternary prograding sequence. These last are visible on the seismic profile ADRIA 95 located in the western portion of the Central Adriatic Basin. The profile was partially processed by Geletti et al. (2008) and now we decided to improve the elaboration of the seismic signal to better define the reflectors characterizing the Plio-Quaternary sequence, the recent deformation of the shallower layers and some bright spots, probably associated to gas presence. We applied a standard processing flow, testing in particular multiple reflections attenuation methods, pre-stack deconvolution techniques, stacking velocity analysis and depth migration within the first 2 sec TWT of the recording trace. The bright spots have been focused by seismic attributes analysis.

Over the last decades some main oil and gas discoveries have been achieved in the West Africa margin and the production is expected to rise in the next years, especially in deep and ultra-deep waters. The main trapping mechanism in the conjugated South Atlantic passive margins (but also in other salt provinces as Caspian basin, Gulf of Mexico, etc; see Fig. 1), is generally connected to salt tectonics. This paper, that arises from a larger thesis work, is carried out by a collaboration between the University of Trieste and Eni E&P Division: its first target is the interpretation of a set of seismic horizons, both in pre- and post-salt sequences, along some confidential depth migrated 2D seismic profiles of the W-Africa margin; a second target is balancing cross-sections to validate the interpretation and to promote a better understanding of the geological evolution of the halocinetic structures. The confidentiality of the data doesn’t allow us to detail the exact position of the profile, but many considerations and results could be regionally applied.

We have observed a strong seismic reflection, with high attenuation below the event, at a depth of 1700-1800 msec TWT (about 700 m below the sea bottom), above the Apulia carbonate platform, in the Salento Adriatic offshore, Otranto Channel. The Merlo-1 explorative well penetrated the Plio-Pleistocene and Upper Miocene sediments covering a structural high of the Cretaceous-Oligocene units of the platform margin. This position, in our opinion, compromised the possibility of crossing the reflector, terminating in onlap or in pinch-out around the structure drilled by the well. We performed dedicated signal analyses in order to evaluate if this bright spot effectively represents a gas reservoir. We used seismic attribute analysis considering amplitude, phase and frequency related attributes, velocity analyses and AVO to improve the interpretation and to obtain semi-quantitative data. Interpretation of all the available seismic profiles was used to map the extension of the possible reservoir and its relation to the Apulia platform margins.

Novel P- and S- wave seismic reflection datasets integrated by topographical, geomorphological, stratigraphic data provide new elements to interpret structure and evolution of a hazardous sector of the North Anatolian Fault (NAF), next to the westernmost segment activated by the 1999 earthquakes. The study area is the Hersek Peninsula, located at the southern margin of Marmara Sea. Multi-component seismic reflection data image the late glacial erosion surface unconformity and overlying sedimentary sequence. The integration with geomorphological data shows two distinct domains: a deltaic system that evolved from south to north with a progressive rotation towards west and a northern sector of the peninsula underlain by an anticline, resulting from tectonic transpression which is responsible for the uplift and tilting of the northern tip. An 8° bend of the NAF in this sector is responsible for transpression and uplifts, as validated also by numerical and analogue simulation. Such structural features match those observed in the evolution of strike-slip fault system, that evolve from large shear zone with fault stepovers, to en-echelon faults and pull-apart basins and finally to localized ruptures. Concentration of stress in single rupture zones can be used as an indicator of increasing seismic hazard.

The analysis of several seismic reflection profiles offshore the Adria plate reveals acomplex spatial-temporal distribution of the carbonate platforms, often linked todifferent conditions of the crustal thicknesses. The “platform sequence”, the“platform-to-basin sequence” and the “oceanic sequence” seem to represent theprincipal paleogeographic domains and are associated with different crustal typeswhich, during the Tertiary age, became the foreland of the southernApennine/Calabrian Arc and the Dinaric/Hellenic Chain. In this work, we have triedto highlight how these main crustal domains affect recent tectonics in a remarkableway. The migration of the Calabrian Arc and the Hellenic Chain brought about aregional compressive regime, which currently affects the whole crustal thickness ofthe Adria plate, causing transpression along the main strike-slip systems of the plate,inversion tectonics in the Salento offshore, and underthrusting below the Dinaric front,whereas the external front of the central-southern Apennines does not seem to beactive any more.