Tuesday, 28 August 2007 - 1:30 PM
2.P1.A-1
New insights into submarine geomorphology and depositional processes along the George V Land continental slope and upper rise (East Antarctica)
Laura De Santis1, Giuliano Brancolini1, Daniela Accettella2, Andrea Cova2, Andrea Caburlotto2, Federica Donda1, Claudio Pelos2, Fabrizio Zgur2, and Massimo Presti1. (1) Dept. of Geophysics of the Lithosphere, Istituto Nazionale Oceanografia e Geofisica Sperimentale, Borgo Grotta Gigante 42/c, Sgonico, Trieste, 34010, Italy, (2) Dept. of Marine Research and Technology, Istituto Nazionale Oceanografia e Geofisica Sperimentale, Borgo Grotta Gigante 42/c, Sgonico, Trieste, 34010, Italy
The PNRA/MOGAM (MOrphology and Geology of Antarctic Margins) project collected swath bathymetric and subbottom acoustic data from the slope and rise of the George Vth Land in 2006 from R/V OGS Explora. Previous studies demonstrated that thick shelf margin prograding sedimentary wedge buried rugged glacial morphology, as in most of the Antarctic margin. The new survey shows that the continental slope and rise is actually incised by a complex network of converging submarine canyons, some of which directly connected to main shelf depressions. Along the slope, canyon erosion by turbiditic flows and by cold dense bottom currents likely prevented the burial of, or exhumed, relict features of the previous glacial topography Further coordinated multidisciplinary investigations of this margin are planned for the International Polar Year, and include multiyear oceanographic measurement of bottom currents, and sedimentological and biological sampling to constraint the present and recent past environment and ecosystems.