FN Archimer Export Format
PT J
TI Denudation systematics inferred from in situ cosmogenic Be-10 concentrations in fine (50-100 mu m) and medium (100-250 mu m) sediments of the Var River basin, southern French Alps
BT 
AF MARIOTTI, Apolline
   BLARD, Pierre-Henri
   CHARREAU, Julien
   PETIT, Carole
   MOLLIEX, Stephane
   AUMAITRE, Georges
   BOURLES, Didier L.
   KEDDADOUCHE, Karim
AS 1:1;2:1;3:1;4:2;5:1,3;6:4;7:4;8:4;
FF 1:;2:;3:;4:;5:;6:;7:;8:;
C1 Univ Lorraine, CNRS, CRPG, UMR 7358, F-54500 Vandoeuvre Les Nancy, France.
   Univ Nice, Geoazur, F-06905 Sophia Antipolis, France.
   Inst Univ Europeen Mer, Lab Geosci Ocean, F-29280 Plouzane, France.
   Aix Marseille Univ, CNRS, Technopole Environm Arbois Meditetranee, INRA,Coll France,UM 34 CEREGE,IRD, BP80, F-13545 Aix En Provence, France.
C2 UNIV LORRAINE, FRANCE
   UNIV NICE, FRANCE
   UBO, FRANCE
   UNIV AIX MARSEILLE, FRANCE
UM LGO
IN DOAJ
IF 3.928
TC 11
UR https://archimer.ifremer.fr/doc/00637/74894/76066.pdf
   https://archimer.ifremer.fr/doc/00637/74894/76067.zip
   https://archimer.ifremer.fr/doc/00637/74894/76068.pdf
   https://archimer.ifremer.fr/doc/00637/74894/76069.zip
LA English
DT Article
AB Marine sedimentary archives are well dated and often span several glacial cycles; cosmogenic Be-10 concentrations in their detrital quartz grains could thus offer the opportunity to reconstruct a wealth of past denudation rates. However, these archives often comprise sediments much finer (< 250 mu m) than typically analyzed in Be-10 studies, and few studies have measured Be-10 concentrations in quartz grains smaller than 100 mu m or assessed the impacts of mixing, grain size, and interannual variability on the Be-10 concentrations of such fine-grained sediments. Here, we analyzed the in situ cosmogenic Be-10 concentrations of quartz grains in the 50-100 and 100-250 mu m size fractions of sediments from the Var basin (southern French Alps) to test the reliability of denudation rates derived from Be-10 analyses of fine sands. The Var basin has a short transfer zone and highly variable morphology, climate, and geology, and we test the impact of these parameters on the observed Be-10 concentrations. Both analyzed size fractions returned similar Be-10 concentrations in downstream locations, notably at the Var's outlet, where concentrations ranged from (4.02 +/- 0.78) x 10(4) to (4.40 +/- 0.64) x 10(4) atoms g(-1) of quartz. By comparing expected and observed Be-10 concentrations at three major river junctions, we interpret that sediment mixing is efficient throughout the Var basin. We resampled four key locations 1 year later, and despite variable climatic parameters during that period, interannual Be-10 concentrations were in agreement within uncertainties, except for one upper subbasin. The Be-10-derived denudation rates of Var subbasins range from 0.10 +/- 0.01 to 0.57 +/- 0.09 mm yr(-1), and spatial variations are primarily controlled by the average subbasin slope. The integrated denudation rate of the entire Var basin is 0.24 +/- 0.04 mm yr(-1), in agreement with other methods. Our results demonstrate that fine-grained sediments (50-250 mu m) may return accurate denudation rates and are thus potentially suitable targets for future Be-10 applications, such as studies of paleo-denudation rates using offshore sediments. 
PY 2019
PD DEC
SO Earth Surface Dynamics
SN 2196-6311
PU Copernicus Gesellschaft Mbh
VL 7
IS 4
UT 000502997300001
BP 1059
EP 1074
DI 10.5194/esurf-7-1059-2019
ID 74894
ER

EF