FN Archimer Export Format
PT J
TI The silicon isotopic composition of surface waters in the Atlantic and Indian sectors of the Southern Ocean
BT 
AF DE LA ROCHA, Christina L.
   BESCONT, Pierre
   CROGUENNOC, Alice
   PONZEVERA, Emmanuel
AS 1:1;2:1;3:1;4:2;
FF 1:;2:;3:;4:PDG-REM-GM-LGM;
C1 Univ Bretagne Occidentale, IUEM, LEMAR, UMR 6539, F-29280 Plouzane, France
   IFREMER, Dept Geosci Marines, Plouzane, France
C2 UBO, FRANCE
   IFREMER, FRANCE
SI BREST
SE PDG-REM-GM-LGM
IN WOS Ifremer jusqu'en 2018
   copubli-france
   copubli-univ-france
IF 4.259
TC 28
UR https://archimer.ifremer.fr/doc/00042/15372/12791.pdf
LA English
DT Article
AB We report here the silicon isotopic composition (delta(30)Si) of dissolved silicon (DSi) from 42 surface water samples from the Drake Passage, the Weddell Gyre, other areas south of the Southern Boundary of the Antarctic Circumpolar Current (ACC), and the ACC near the Kerguelen Plateau, taken between the beginning of February and the end of March 2007. From the beginning to end of the cruise (ANTXXIII/9), DSi diminished in the Antarctic by 50 mu mol L(-1) while concentrations of nitrate + nitrite and phosphate showed no net decline, indicating that the high seasonal Si/N removal ratios well known for the Southern Ocean may be more related to the strength of the silicate pump in the Southern Ocean than to the instantaneous Si/N uptake ratio of diatoms. The delta(30)Si of DSi in samples containing more than 20 mu M DSi were strongly negatively correlated to DSi concentrations, supporting the use of delta(30)Si as a proxy for DSi removal. The "open system" fractionation observed, epsilon = -1.2 +/- 0.11 parts per thousand, agrees well with results from previous work in other areas, and the estimate of the initial delta(30)Si of DSi of + 1.4 parts per thousand is not far off observations of the delta(30)Si of DSi in Winter Water (WW) in this area. Results were used to model DSi draw down in the past from the delta(30)Si of sediment cores, although isotopic fractionation during silica dissolution appeared to influence the d 30 Si of some surface water samples, inviting further study of this phenomenon. (C) 2011 Elsevier Ltd. All rights reserved.
PY 2011
PD SEP
SO Geochimica Et Cosmochimica Acta
SN 0016-7037
PU Pergamon-elsevier Science Ltd
VL 75
IS 18
UT 000293775200012
BP 5283
EP 5295
DI 10.1016/j.gca.2011.06.028
ID 15372
ER

EF