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As the definition of contourites has widened to embrace a large spectrum of sediments in so-called mixed systems, the distinction between contourites and turbidites has become at times vague. The case history of sediment Drift 7 off the Antarctic Peninsula is analysed in this paper in the light of newly acquired swath bathymetry data. The co-existence of various sedimentary processes is reflected in a complex morphology: erosional gullies produced by debris flows on the upper part of the continental slope; deeply incised channels at the slope base; main trunk-type inter-drift turbidity channels separating the drifts; slide scars; undulating depositional bedforms interpreted as bottom-current sediment waves; fluid escape structures perhaps associated with deep-water coral bioherms. The data suggest that Drift 7 is a genuine sediment drift in which bottom currents pirate the sediment of the turbidity currents. Finally, we propose that the control on location and elongation of the drift is inherited from an older margin structure. The relationships between bottom current and deposition are investigated through a comparison with the SE Greenland continental margin, an analogous counterpart in the northern hemisphere.

Well-preserved SSE-dipping low-angle normal faults (LANF) active during the Early Permian (Cisuralian) were recognized along the northern margin of the Orobic Basin (central Southern Alps, N Italy). These faults, which escaped most of the Alpine deformations, exhumed the Variscan basement during the deposition of the upper part of the Lower Permian succession (Pizzo del Diavolo Formation). Fault planes show evidence of frictional processes typical of the upper crust associated with hydrothermal circulation, responsible for the deposition of cm to m thick tourmalinite and Uranium mineralization.The recognized LANFs interacted with high-angle normal faults producing half grabens that stored the Lower Permian deposits, where synsedimentary fault activity in their hangingwall is testified by abrupt vertical and lateral facies changes, thickness variations and by soft-sediment deformations.Mesoscopic structures, exposed in the hangingwall of a major LANF (the Aga-Vedello Fault system) along a synthetic high-angle normal fault, include conjugate normal faults, horst-and-graben, domino-

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Abstract. We use various geophysical datasets (multibeam and singlebeam echosounder data, sub-bottom profiling Chirp and sonar data and very high-resolution boomer seismic data) along with published sedimentological data and depth data from nautical charts in order to create models of the depth of the seafloor and the base of Holocene marine sediment in the Gulf of Trieste. The two models are later used in order to calculate the thickness of marine Holocene sediment which has been depositing on the Late Pleistocene alluvial plain since the Holocene transgression in the Italian and Slovenian parts of the gulf. Thicker Holocene marine sedimentary sequences averaging at around 5 m are characteristic for the southeastern part of the gulf. In other parts of the gulf the Holocene marine sedimentary cover is very thin or even absent, except in close proximity to the shoreline and fluvial sediment sources, in the area of the Trezza Grande paleodelta and above topographic depressions of the Late Pleistocene base. The presented datasets available from the OGS SNAP data repository (http://doi.org/cpz2) represent a valuable reference for a wide variety of research disciplines dealing with the dynamic Earth system in the Gulf of Trieste and could be used as a valuable tool for designing sampling and geophysical campaigns in the studied area.

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The western part of the Gulf of Taranto, southern Italy, is a seismically active area with high sediment supply. New swath bathymetry and sub-bottom profiler (CHIRP) data were acquired on board R/V OGSExplora during the WGDT cruise. The data were analyzed to describe the seafloor morphology and the acoustic facies of relevant morphologic features. Special attention was given to the features produced by mass wasting and softsediment deformations. The features identified include: slides and slide scars, debris flow deposits, enigmatic dipslope trending sub-parallel linear depressions, and alongslope undulations inferred to have been produced either by creeping or sediment deposition by hyperpycnal flows. The description of these features contributes to the characterization of the Calabria foreland basin system and provides an analogue for other basins similarly affected by a close relation between sediment supply and active tectonics.