||Jorry Stephan1, Jegou Isabelle1, Emmanuel Laurent2, Silva Jacinto Ricardo1, Savoye Bruno1
||1 : IFREMER, Lab Environm Sedimentaires, F-29280 Plouzane, France.
2 : Univ Paris 06, Lab Biomineralisat & Environm Sedimentaires, ISTeP, CNRS,UMR 7193, F-75252 Paris 05, France.
||Marine Geology (0025-3227) (Elsevier Science Bv), 2011-01 , Vol. 279 , N. 1-4 , P. 148-161
|WOS© Times Cited
||last deglaciation, overbank deposits, turbidity currents, Var Sedimentary Ridge, Ligurian Sea
||The Var turbiditic system located in the Ligurian Sea (SE France) is an intermediate mud/sand-rich system. The particularity of the Var deep-sea fan is its single channel with abrupt bends and its asymmetric and hyper-developed levee on the right hand side: the Var Sedimentary Ridge. Long-term sediment accumulation on the Var Sedimentary Ridge makes this an ideal target for studying the link between onshore climate change and deep-sea turbidite stratigraphy. This paper focuses on the establishment of the first detailed stratigraphy of the levee, which is used to analyze the timing of overbank deposition throughout the last deglaciation. Main results indicate that high variability in turbidite frequencies and deposition rates along the Var Sedimentary Ridge are determined by two main parameters: 1) the progressive decrease of the levee height controlling the ability of turbidity currents to spill out from the channel onto the levee, and 2) climatic variations affecting the drainage basin, in particular changes in glacial condition since late Last Glacial Maximum to early Holocene. Compared to other deep-water areas, this study confirms the ability of turbiditic systems to record past climatic events on millennial timescales, and underlines the influence of European deglaciation on the observed decrease in turbidite activity in the Var canyon. The presence of a very narrow continental shelf and a single, large channel-levee system makes the Var Sedimentary Ridge a unique example of climate-controlled turbiditic accumulations. (C) 2010 Elsevier B.V. All rights reserved.
||Access on demand
|Author's final draft