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Salt tectonics at salt-bearing margins is often interpreted as the combination of gravity spreading and gravity gliding, mainly driven by differential sedimentary loading and margin tilting, respectively. Nevertheless, in the Western Mediterranean Sea, the classical salt-tectonic models are incoherent with its morpho-structural setting: Messinian salt was deposited in a closed system formed several Ma before the deposition, horizontally throughout the entire deep basin, above a homogenous multi-kilometer pre-Messinian thickness. The subsidence is purely vertical in the deep basin, implying a regional constant initial salt thickness. The post-salt overburden is homogenous and the distal salt deformation occurred before the mid-lower slope normal-fault activation. Instead, the compilation of MCS and wide-angle seismic data highlighted a clear coincidence between crustal segmentation and salt morphology domains. The salt structures change morphology at the boundary between different crustal natures. Regional thermal anomalies and/or fluid escapes, associated with the exhumation phase, or mantle-heat segmentation, could therefore play a role in adding a further component to the already known salt-tectonics mechanisms. The compilation of crustal segmentation and salt morphologies in different salt-bearing margins, such as the Santos, Angolan, Gulf of Mexico and Morocco-Nova Scotia margins, seems to depict the same coincidence. In view of the evidences observed in the Western Mediterranean Sea, the influence of the temperature parameter on salt deformation should not be overlooked and warrants further investigation.

The structural setting of the northern Ionian Sea is the result of the collision between the Calabrian Accretionary Wedge (CAW) and the adjacent foreland, i.e. the Apulian Carbonate Platform. The CAW represents a sector of the Apennine accretionary system extending in the Ionian Sea, bounded to the west by the Malta Escarpment and to the east by the Apulia Escarpment. This work presents the results of the interpretation of new seismic and bathymetric data acquired on the north-eastern edge of the CAW, in the N-Ionian Sea. The data interpretation has identified four main structural domains from NE to SW: 1. The Apulian carbonate Platform consisting of foreland shelf and transitional Mesozoic-Cenozoic carbonate deposits; 2. A narrow foredeep basin, filled by a very thick Plio-Quaternary succession; 3. A deformed domain, at the front of the CAW, incorporating thrusted foredeep sequences and a carbonate block of the Apulian Platform (Transpressed Apulian Block, TAB); 4. A highly deformed pre-Pliocene accretionary wedge. A mid-Pliocene unconformity interpreted on both the CAW and Apulian Foreland suggests that a regional tectonic event occurred at that time, related to the evolution of Calabrian Arc, moving on the subducting oceanic Ionian slab before the collision. This event would correspond to a main tilting and faulting phase of the Apulian Foreland during the diachronous oblique collision with the CAW. The collision and the presence of a remnant of Ionian foreland at the southern front of the accretionary prism, caused a gradual transition to a transpressional tectonics which produced the uplift of the TAB. The TAB would be the south-east continuation of the Amendolara ridge transpressed structure, which forms the offshore extension of the Pollino range. This transpressed shear zone involving the Apulian Foreland developed above the transition between the Adriatic continental crust and the subducting Ionian oceanic crust.

The sedimentary wedge of the Apennines foredeep in the Central Adriatic Sea provides evidence of westward tilting of the foreland during the Lower Pliocene. The wedge was covered by an Upper Pliocene-Lower Pleistocene sequence of parallel and horizontal strata that onlapped onto the pre-wedge sediments. The Southern Apennines contain younger foredeep growth strata because the chain front migrated until the Lower Pleistocene. Seismic profiles from the Central and Southern Apennines foredeep show a regional, apparently contrasting eastward-dipping set of post-growth parallel layers that are covered by a Middle/Upper Pleistocene Prograding Sedimentary Wedge (PSW), which is particularly thick in the Central Adriatic basin. In accordance with the “Law of Original Horizontality” and by excluding possible exceptions to this law (inclined depositions in several specific frameworks), the observed geometric setting can be explained as an effect of post-deposition inversion of the previous orogen-ward tilting. We infer that the driving mechanism of uplift was the regional isostatic rebound of the Adria foreland, which started in the Middle Pleistocene and is still active as indicated by the current uplift of Adria and by the passively raised chain. Under the same conditions, the greater the tilting of the foredeep during the chain migration, the greater the degree of isostatic rebound. The rheology of the foreland and sedimentary loading are also key elements of these crustal-scale vertical movements. Furthermore, normal faults and greater foredeep uplift of the foreland can play local roles in short-wavelength deformations. The current axis of the chain, which was affected by imbrication of the Apennine and Apulia units, is now subject to higher rates of rebound and erosion. We infer that inversion of some of the previous faults that originated the buried western margin of the Apulia carbonate platform (AP) triggered the extensional seismicity that is recorded along the chain. The rapid uplift of the foreland and of the overlying thrust belt since the Middle Pleistocene caused a change in the drainage network on the Adriatic side of the chain from a longitudinal pattern to a transverse pattern. In addition, erosion of the uplifted units contributed to the high rate of deposition of the PSW in the Adriatic foreland basin. The regional rebound process that is proposed in this work implies a primary role of the AP buoyancy and rejects the hypothesis of its current passive sinking, which is often regarded as the primary source of Apennines tectonics.

An analysis of multichannel seismic reflection data was conducted focusing on the comparison between the Messinian Salinity Crisis (MSC) and Plio-Quaternary (PQ) evolution of the eastern Sardo-Provençal and northern Algero- Balearic basins and related margins in the West Mediterranean Sea. Both basins were completely opened during the MSC and their well-defined seismic stratigraphy is very similar in the deep parts. The primary difference between these two basins is due to their different pre-MSC extensional history, including the opening age and the stretching factors. These factors influenced the occurrence of post-MSC salt tectonics on these margins.

We have applied an attribute-based autopicking algorithm to reflection seismics with the aim of reducing the influence of the user’s subjectivity on the picking results and making the interpretation faster with respect to manual and semiautomated techniques. Our picking procedure uses the cosine of the instantaneous phase to automatically detect and mark as a horizon any recorded event characterized by lateral phase continuity. A patching procedure, which exploits horizon parallelism, can be used to connect consecutive horizons marking the same event but separated by noise-related gaps. The picking process marks all coherent events regardless of their reflection strength; therefore, a large number of independent horizons can be constructed. To facilitate interpretation, horizons marking different phases of the same reflection can be automatically grouped together and specific horizons from each reflection can be selected using different possible methods. In the phase method, the algorithm reconstructs the reflected wavelets by averaging the cosine of the instantaneous phase along each horizon. The resulting wavelets are then locally analyzed and confronted through crosscorrelation, allowing the recognition and selection of specific reflection phases. In case the reflected wavelets cannot be recovered due to shape-altering processing or a low signal-to-noise ratio, the energy method uses the reflection strength to group together subparallel horizons within the same energy package and to select those satisfying either energy or arrival time criteria. These methods can be applied automatically to all the picked horizons or to horizons individually selected by the interpreter for specific analysis. We show examples of application to 2D reflection seismic data sets in complex geologic and stratigraphic conditions, critically reviewing the performance of the whole process.

The Kvarner area is located in the Northern Adriatic Sea, between the south-east Istrian Swell, the Rijeka coast and the Croatian sea boundary. It includes several islands, representing the outcropping parts of anticlines produced by the compressional/transpressional deformation of the External Dinaric Chain. An extensive 2D seismic dataset, acquired for hydrocarbon exploration and calibrated by wells, allowed us to reconstruct the time structural maps in Kvarner and unravel its regional fault pattern. The Dinaric compressional phase affected the area in the Late Cretaceous, with both thin- and thick-skinned tectonics related to Adriatic Carbonate Platform (AdCP) succession rigidity. Structural highs facing the Kvarner offshore from the Istrian inland continue through the Kvarner and Rijeka bays and outcrop in the islands. These anticlines, originating from the pre-Messinian Dinaric thrust system, were reactivated by the post-Messinian transpression, as testified by flower structures. Several sharp valleys represent two main low structural lineaments, developed between the anticlines and partially incised during the Messinian. They were observed throughout the entire studied area, specifically in the western part of the bays, where the lineament continues through the valleys and penetrates the SW-Istria land. Data show that the Messinian erosional effect and sedimentation patterns were influenced and driven by the morphology of older structures produced by the Dinaric compressional phase.