Dissolved thorium isotopes in seawater samples collected during the IN2017-V01 voyage of the RV Investigator

Samples were collected from the East Antarctic margin, aboard the Australian Marine National Facility R/V Investigator from January 14th to March 5th 2017 (IN2017_V01; Armand et al., 2018). This marine geoscience expedition, named the “Sabrina Sea Floor Survey”, focused notably on studying the interactions of the Totten Glacier with the Southern Ocean through multiple glacial cycles.

Ten litres seawater samples were collected using a CTD rosette equipped with Niskin® bottle and filtered through a 0.45µm Millipore GWSC04510: Ground Water sampling capsule, directly into acid-cleaned 10 L polyethylene jerrycans. Samples were then acidified to pH 2 with 2 mL/L of distilled 6M HCl in a laminar flow hood. These samples were analysed for thorium isotopes (230Th and 232Th), a tracer of particle dynamics.

The sample preparation was carried out in the clean lab of the Institute for Marine and Antarctic Studies (UTAS, Hobart). Seawater samples were acidified with HF (final concentration 0.6 mM, Middag et al., 2015), spiked with 10 pg of 229Th (NIST 4328C, National Institute of Standards and Technology, USA) and left to equilibrate for at least 48h. Samples were preconcentrated using Nobias® PA1L (Hitachi Technologies, Japan) cartridges, following the procedure of Pérez-Tribouillier et al., (2019). The separation and purification of thorium isotopes were performed by anion-exchange chemistry (Anderson et al., 2012).

Purified Th fractions were analysed using an Element II Sector Field Inductively Coupled Plasma Mass Spectrometer (SF-ICP-MS, Thermo Fischer Scientific, Bremen, Germany) at the Central Science Laboratory (CSL) of the University of Tasmania. Sample introduction was achieved using an Aridius® II desolvating nebulizer (DSN, CETAC Technologies, USA). The capacitive guard electrode was activated to maximise signal sensitivity.

Raw intensities of 230Th and 232Th were blank and mass bias corrected. Concentrations were calculated using the isotope dilution equation reported in Sargent et al., (2002).

References

- Anderson, R. F., Fleisher, M. Q., Robinson, L. F., Edwards, R. L., Hoff, J. A., Moran, S. B., … Francois, R. (2012). GEOTRACES intercalibration of 230Th, 232Th, 231Pa, and prospects for 10Be. Limnology and Oceanography: Methods, 10(4), 179–213.

- Armand, L. K., O’Brien, P. E., Armbrecht, L., Baker, H., Caburlotto, A., Connell, T., … Young, A. (2018). Interactions of the Totten Glacier with the Southern Ocean through multiple glacial cycles (IN2017-V01): Post-survey report. ANU Research Publications

- Middag, R., Séférian, R., Conway, T. M., John, S. G., Bruland, K. W., and de Baar, H. J. W. (2015). Intercomparison of dissolved trace elements at the Bermuda Atlantic Time Series station. Marine Chemistry, 177, 476–489.

- Pérez-Tribouillier, H., Noble, T. L., Townsend, A. T., Bowie, A. R., and Chase, Z. (2019). Pre-concentration of thorium and neodymium isotopes using Nobias chelating resin: Method development and application to chromatographic separation. Talanta, 1–10.

- Sargent, M., Harrington, C., and Harte, R. (2002). Guidelines for Achieving High Accuracy in Isotope Dilution Mass Spectrometry (IDMS). Guidelines for Achieving High Accuracy in Isotope Dilution Mass Spectrometry (IDMS). Royal Society of Chemistry.

Identification info

Alternate title: Dissolved thorium isotopes in seawater samples collected during the IN2017-V01 voyage of the RV Investigator

Date (Publication): 2023-04-03

Edition: 1

Citation identifier

Dataset DOI

Title: Information and documentation - Digital object identifier system

Date (Publication): 2012-04-23

Citation identifier: ISO 26324:2012

Citation identifier: doi:10.26179/r1j1-e757

Originator

Creac'h, L., Noble, T.L., Townsend, A. and Perez Tribouillier, H.

Publisher

Australian Antarctic Data Centre

Principal investigator

CREAC'H, LAYLA

Institute for Marine and Antarctic Studies

20 Castray Esplanade, Battery Point

Hobart

TAS

7004

Australia

Principal investigator

NOBLE, TARYN L

Institute of Marine and Antarctic Studies

20 Castray Esplanade

Hobart

Tas

7004

Australia

Collaborator

CREAC'H, LAYLA

Institute for Marine and Antarctic Studies

20 Castray Esplanade, Battery Point

Hobart

TAS

7004

Australia

Collaborator

TOWNSEND, ASHLEY

Central Science Laboratory, Hobart Campus, Chemistry Building

Private Bag 74

Hobart

TAS

7001

Australia

Collaborator

PEREZ TRIBOUILLIER, HABACUC

Name: CAASM Metadata

Other citation details: Unreleased data

Website: https://data.aad.gov.au/metadata/records/AAS_4419_Th_isotopes_SW

Purpose: These data were collected to determine the concentration of dissolved thorium isotopes in seawater, in order to trace particles distributions in the water column.

Status: Completed

Custodian

AU/AADC > Australian Antarctic Data Centre, Australia - AADC, DATA OFFICER (DATA CENTER CONTACT)

Australian Antarctic Division

203 Channel Highway

Kingston

Tasmania

7050

Australia

+61 3 6232 3244

+61 3 6232 3351 (facsimile)

Topic category

Oceans

Extent