FN Archimer Export Format
PT J
TI Millennial-Scale Response of a Western Mediterranean River to Late Quaternary Climate Changes: A View from the Deep Sea
BT 
AF BONNEAU, Lucile
   JORRY, Stephan J.
   TOUCANNE, Samuel
   SILVA JACINTO, Ricardo
   EMMANUEL, Laurent
AS 1:1,2,3;2:3;3:3;4:3;5:1,2;
FF 1:PDG-REM-GM-LES;2:PDG-REM-GM-LES;3:PDG-REM-GM-LES;4:PDG-REM-GM-LES;5:;
C1 Laboratoire Biominéralisations et Environnements Sédimentaires, Université Pierre et Marie Curie, Paris, France
   Institut des Sciences de la Terre de Paris, Paris, France
   Laboratoire Environnements Sédimentaires, Institut français de recherche pour l’exploitation de la mer, F-29280 Plouzané, France
C2 UNIV PARIS 06, FRANCE
   CNRS, FRANCE
   IFREMER, FRANCE
SI BREST
SE PDG-REM-GM-LES
IN WOS Ifremer jusqu'en 2018
   copubli-france
   copubli-univ-france
IF 2.689
TC 34
UR https://archimer.ifremer.fr/doc/00248/35925/34447.pdf
LA English
DT Article
CR ESSDIV
BO Pourquoi pas ?
AB Although it is widely accepted that erosion and sediment transfer respond to millennial-scale climatic variability, these changes remain difficult to detect in marine sedimentary archives. In the Var sediment-routing system, northwestern Mediterranean Sea, the absence of a continental shelf results in a direct connection between the Var River mouth and the deep basin during both highstand and lowstand conditions. This makes the Var sediment-routing system an ideal target to test whether rivers can transmit climate-driven high-frequency changes in sediment flux to the ocean. On the basis of an unprecedented (centennial-to-millennial-scale) resolution in turbidite sequences, we reconstructed the activity of turbidity current overflows along the deep-sea Var Sedimentary Ridge over the past 75 kyr. The overflow activity is highest (one event every 10-30 yr) during maximum glacial conditions (30 kyr-16 kyr ago [ka]) and rapidly decreases (down to one event every 100-500 yr) during the last glacial-interglacial transition (Termination 1). During marine isotope stage (MIS)4 and MIS3 (75-30 ka), peaks in the overflow activity occurred synchronously with cold and arid Dansgaard-Oeschger stadials, while warmer and wetter interstadial conditions correspond to low overflow activity. We conclude that overflow activity on the Var Sedimentary Ridge mainly reflects changes in the magnitude of hyperpycnal currents flowing in the turbiditic channel-levee system in relation with variations in suspended-sediment concentration during Var River floods. We show that this signal is sensitive to changes in pure sediment flux induced by climatic perturbations occurring inland: (1) the decrease in glacier-derived sediment input after glacier retreat and (2) changes in erosion induced by shifts in the vegetation cover in response to Dansgaard-Oeschger climate swings.
PY 2014
PD NOV
SO Journal Of Geology
SN 0022-1376
PU University of Chicago
VL 122
IS 6
UT 000346125200004
BP 687
EP 703
DI 10.1086/677844
ID 35925
ER

EF