Name: Stable isotopic composition of biogenic and dissolved silicon (δ30Si) over the Northern Kerguelen Plateau (South West Indian Ocean GEOTRACES Section, SWINGS-GS02).
Published: 2025-03-17
License: https://creativecommons.org/licenses/by/4.0/
Keywords: Silicon, Isotopes, δ30Si, Dissolved Si, Biogenic Si, GEOTRACES

Silicic acid concentration (Dissolved silicon, DSi: µmol.L^-1), Isotopic composition of Dissolved silicon (δ³⁰Si_DSi: ‰), Isotopic composition of Biogenic silicon (δ³⁰Si_BSi: ‰).

Note that :

Total fraction for BSi isotopic composition is available from Niskin bottles after filtration (> 0.8µm)
Fraction for DSi isotopic composition is available from Niskin bottles after filtration (< 0.8µm)

Disciplines

Chemical oceanography, Biological oceanography

Parameters

Silicate concentration parameters in the water column , Stable isotopes in water bodies

Devices

spectrophotometers , isotope ratio mass spectrometers

Keywords

Silicon, Isotopes, δ30Si, Dissolved Si, Biogenic Si, GEOTRACES

Location

-47.936224N, -55.561966S, 77.812504E, 61.699224W

Licence

Acknowledgements

We would like to thank Captain A. Eyssautier, LDA and GENAVIR officers, engineers, technicians and the crew of the R/V Marion Dufresne for their professional assistance during the SWINGS cruise. We would like to thank the chief scientists Catherine Jeandel and Hélène Planquette. We also thank Emmanuel de Saint-Léger and Fabien Pérault (CNRS DT INSU) for their help with the preparation, deployment and maintenance of the rosette/in situ pumps. The SWINGS project was supported by the Flotte Océanographique Française (10.17600/18001925), Agence Nationale de la Recherche (ANR 19-CE01-0012), CNRS/ INSU (Centre National de la Recherche Scientifique/Institut National des Sciences de l’Univers) through its LEFE actions, Université de Bretagne Occidentale, and IsBlue project, Interdisciplinary graduate school for the blue planet (ANR 17-EURE-0015) and co-funded by a grant from the French government under the program ‘Investissements d’Avenir” embedded in France 2030. The International GEOTRACES Programme is possible in part thanks to the support from the U.S. National ScienceFoundation (Grant OCE-2140395) to the Scientific Committee on Oceanic Research (SCOR). We are grateful to Marine Piéjus for on-board sampling and filtering; Mustapha Benrahmoune (LOCEAN) for managing clean laboratory; Pierre Burckel and the PARI analytical platform (IPGP) for ICP-MS; Stéphanie Jacquet for on-board filtration units; Irina Djouraev and the Alysés analytical platform (IRD-SU) for ICP-MS too; the PANOPLY analytical platform (CNRS-CEA-Université Paris Sud-UVSQ) for the MC-ICP-MS analysis. Maps were drawn with the M_Map Matlab toolbox (Pawlowicz, 2020). This study has been conducted using E.U. Copernicus Marine Service Information. The authors thanks EUR IPSL Climate Graduate School for financial support.

Note

Concentrations of DSi with their associated δ³⁰Si_DSi and δ³⁰Si_BSi signatures. LSi concentrations are also shown. Standard deviations are shown for triplicate and more analyses (*); for duplicate analyses (i.e. without *), the range is used instead. No SD implies no replication of δ³⁰Si measurement.

Devices

Samples were collected using a Rosette equipped with 12 L Niskin bottles. Between 1 and 6 L of seawater was immediately filtered on-board through polyethersulfone (PES) membranes (PALL SUPOR®, 47 mm, 0.8 μm pore size) with pressurised filtration units to separate the dissolved part (DSi) from the particulate part (BSi).

Measurements of DSi concentrations were carried out by colorimetry following Grasshoff et al., (1983).

BSi concentrations are available from Deteix et al. (2024) and on Seanoe database at the following address: https://doi.org/10.17882/97947

After sample preparation, deviation from the average crustal stable isotopic composition were measured as at LSCE-IPSL, Panoply platform, on a MC (Multi Collectors)-ICP-MS Thermo Neptune+ in dry plasma mode following Closset al. (2016) and reported in ‰ as d³⁰Si relative to Quartz NBS28 (Reference Material 8546).

Closset, I., D. Cardinal, M. Rembauville, F. Thil, and S. Blain. 2016. Unveiling the Si cycle using isotopes in an iron-fertilized zone of theSouthern Ocean: from mixed-layer supply to export. Biogeosciences 13: 6049–6066. https://doi.org/10.5194/bg-13-6049-2016

Deteix, V., E. Cotard, S. Caquineau, W. M. Landing, F. Planchon, T. Ryan-Keogh, and D. Cardinal. 2024. Biogenic and lithogenic silicon along the GEOTRACES south West Indian Ocean section (SWINGS-GS02) and the islands mass effect on regional Si biogeochemical cycle. Mar. Chem. 263–264: 104412. https://doi.org/10.1016/j.marchem.2024.104412

Grasshoff, K., Ehrhardt, M., Kremling, K. 1983. Methods of Seawater Analysis. Velag Chemie Weinhein, New York.

Data

File	Size	Format	Processing	Access
SWINGS_DATA_Niskin_DSi_δ30Si	2 Ko	CSV	Quality controlled data		Download

Sea scientific
open data
publication

Stable isotopic composition of biogenic and dissolved silicon (δ30Si) over the Northern Kerguelen Plateau (South West Indian Ocean GEOTRACES Section, SWINGS-GS02).

Disciplines

Parameters

Devices

Keywords

Location

Devices

Data

Sea scientific
open data
publication

Stable isotopic composition of biogenic and dissolved silicon (δ30Si) over the Northern Kerguelen Plateau (South West Indian Ocean GEOTRACES Section, SWINGS-GS02).

Disciplines

Parameters

Devices

Keywords

Location

Devices

Data

Sea scientificopen datapublication

Sea scientific
open data
publication