Sediment dynamics on the Ross Sea continental slope: results from the Rosslope Project.

We present the main results concerning the PNRA Rosslope Project (Past and present sedimentary dynamic in the ROSS Sea: a multidisciplinary approach to study the continental SLOPE). The project aims to investigate the relationships among geological, geomorphological, geophysical characteristics of the sea floor, water-mass circulation and Late Cenozoic environmental variations in two selected areas of the Ross Sea 1) the outer–shelf and the continental slope of the Adare and Central Basins, as outlet areas of the High Salinity Shelf Water (HSSW) into the Southern Ocean 2) the outer–shelf and the continental slope East of the Pennell-Iselin Banks, as the main overflow area of the Ice Shelf Water (ISW). Four cores were selected: three in the East part of the Iselin Bank and one in the Central Basin. Magnetic susceptibility, X-radiographs, grain-size, organic matter, micropaleontological, geochemical and mineralogical data were performed Micropaleontological data on diatom assemblages from selected samples demonstrate the existence of a strong reworking at least in eastern site, considering the widespread occurrence of fossil taxa along the investigated sediment cores 14C measurements gave ages ranging from 6 ky to 34 ky BP on selected samples. Geophysical data (2D seismic line) were acquired from the outer shelf to the upper slope of the East part of Iselin Bank . The results of the processed data were correlated to the adjacent existing seismic lines in order to define a more detailed model representing the Late Cenozoic sedimentation of this zone. Data processing is ongoing, but it is already possible to identify the main factors that are conditionig and have conditioned the sedimentation processes in the area.