GORINI , Christian

The Amazon River extends from the Andes to the Atlantic continental margin and has the world's highest flux of suspended sediment and terrestrial organic carbon to the ocean, leading to the formation of one of the world's largest deep-sea turbiditic fans, 10 km thick, down to water depths of 4500 m. The fan is undergoing gravitational collapse,...

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Based on new ('SESAME 01' cruise) and previous seismic reflection data, this paper evidences the effects of the Messinian Salinity Crisis on the sedimentation at the western Sardinian margin. In the lower part of the margin, Messinian detrital deposits are organized into two successive, 300 m thick units. According to their shape, facies and...

Submarine canyons are usually described as erosive conduits incising the continental slope through retrogressive sediment failures and active erosion by gravity flows. Only a few studies have revealed that canyon deepening is possible under conditions of net sediment deposition.In the present study, we used bathymetry/backscatter data, chirp...

The geodynamic processes in the western Mediterranean are driven by both deep (mantle) processes such as slab-rollback or delamination, oblique plate convergence and inherited structures. The present-day deformation of the Alboran Sea and in particular the Nekor basin area is linked to these coeval effects. The seismically active Nekor basin is...

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The Ionian Calabrian margin, offshore southern Italy, is a tectonically active area, located above a subduction zone dominated by rollback of the African plate. A variety of mass wasting features are known to occur along the inner continental slope, based on seafloor mapping during the Italian project MaGIC (Marine Geohazards Along the Italian...

The continental shelf offshore the present-day Amazon River is known to have hosted a mixed carbonate-siliciclastic platform from the Late Paleocene to the Late Miocene. However, character of this platform has not been properly described and the nature and timing of the cessation of carbonate sedimentation remains controversial. In the present...

The Amazon fan contains a gas hydrate province known from a bottom-simulating reflection (BSR) that lies within an upper slope compressional belt. In this study, the extent and character of the BSR and its relation to thrust-fold structures is examined using a grid of 2D and 3D seismic data. We show the BSR to comprise a series of elongate...

The Ionian Calabrian margin is a tectonically active area, and is part of the Calabrian Arc, that is the SE tip of the arcuate Appeninc-Maghrebide fold and thrust belt, generated through the Neogene northwest-oriented subduction of the Nubia plate below the Eurasian plate. Based on seabed mapping carried out during the national Project MaGIC...

The stability of natural gas hydrate accumulations on continental margins has mainly been considered in terms of changes in seawater pressures and temperatures driven from above by climate. We present evidence from the Amazon deep-sea fan for stability zone changes driven from below by fluid upwelling. A grid of 2D and 3D multichannel seismic...

Gas hydrates are ice-like compounds of water and volatiles (mainly methane) that are stable in deep-sea sediments due to high pressures and low temperatures. Changes in oceanographic conditions that reduce their stability field (e.g. sea level lowering, bottom water warming) have been suggested to trigger continental slope failures. The Amazon...

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The Messinian salinity crisis (MSC) is characterized by gigantic erosion that remodels the margins while a thick, essentially evaporitic and detrital, sedimentary sequence forms in the deep basins. Based on recent (MAURESC, 2003) and earlier (MESEA 1, 1990; MAGIRAA, 1996; GEOBREST, 2002) seismic reflection data, this work brings to light the...

Extra sets of 2D multi-channel seismic and chronostratigraphic data allowed us to undertake analyses of source to sink processes and triggering mechanisms of the gigantic megaslides previously documented off the NW and SE steep slope settings of the Foz do Amazonas basin. As these megaslides comprise two sets of stacked allochthonous masses...

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The North Anatolian Fault (NAF) is a >1200 km-long continental strike-slip fault system, acting as the plate boundary between Eurasia and Anatolia. West of the Yeniçaga fork in Turkey, the NAF divides in two main strands: the Main Marmara Fault crossing the Marmara Sea to the North, and a southern branch of the NAF crossing the Biga Peninsula....

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The Alboran Sea (Western Mediterranean) is a relatively small ocean basin connected with the Atlantic that provides a rich archive of tectonic and sedimentary processes at distinct temporal and spatial scales during the Quaternary. Since the collisional boundary of the Eurasia-Nubia plates crosses the Alboran Sea, this basin is also the locus...

The offshore Niger Delta provides a spectacular example of gravity collapse tectonics, but the timing of shale mobilisation remains poorly understood. Here we present new information from the western Niger Delta, based on a detailed interpretation of a 3D seismic volume, calibrated with biostratigraphic data from exploration wells. The study...

Numerous studies of the offshore Niger Delta have documented substrate-related collapse systems based on widely spaced 2D seismic data that generally lack detailed age calibration, but shale evolution through time remains poorly understood. This is investigated in this study through a detailed interpretation of an industry 3D seismic survey and...