||Zaragosi Sébastien1, Bourillet Jean-Francois2, Eynaud Frédérique1, Toucanne Samuel1, Denhard Benjamin1, Van Toer Aurélie1, Lanfumey Valentine1
||1 : Univ Bordeaux 1, UMR 5805, EPOC, Dept Geol & Oceanog, F-33405 Talence, France.
2 : IFREMER, Lab Environm Sedimentaires, F-29280 Plouzane, France.
||Geo-Marine Letters (0276-0460) (Springer), 2006-12 , Vol. 26 , N. 6 , P. 317-329
|WOS© Times Cited
||Sedimentation, Glaciation, Turbidity, Deep sea, Bay of Biscay, French Atlantic margin
||The compilation of results obtained on three giant piston cores from the Whittard, Shamrock and Guilcher turbidite levees reveals a high-resolution stratigraphic record for the Bay of Biscay. Due to the abundance of reworked sediments in these sedimentary environments, a specific methodological approach, based on an X-ray-assisted subsampling phase associated with sedimentological, geochemical and micropalaeontological analyses, was implemented. With an accurate chronological framework, this multi-proxy investigation provides observations on the 'Fleuve Manche' palaeoriver and the British-Irish Ice Sheet (BIS) histories over the last 20,000 years. The results obtained highlight the direct influence of the decay of the BIS on the Bay of Biscay deep-sea clastic sedimentation during the last European deglacial phase. During this period, the annual BIS cycle of meltwater seems enough to generate seasonal turbidity currents associated with exceptional sedimentation rates in all the Celtic and Armorican turbidite systems. With very high sedimentation rates, the turbidite levees represent the main deep-sea clastic depositional area. Long coring combined with a very careful subsampling method can provide continuous high-resolution palaeoenvironmental signals.