Rare Earth Elements concentrations in seawater samples collected during the IN2017-V01 voyage of the RV Investigator

Brief description

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 filter 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.

Back to the home laboratory (IMAS Trace-Metal Lab, UTAS, Hobart, Australia), sub-samples of 60 mL were taken up from the large volume of seawater, and pre-concentrated for Rare Earth Elements (REE) using pre-packed Nobias® PA1L (Hitachi Technologies, Japan) chelating resin cartridges following the method of Hatje et al., (2014).
Dissolved REE concentrations were determined in pre-concentrated samples using an Element 2 Sector Field Inductively Coupled Plasma Mass Spectrometer (SF-ICP-MS, Thermo Fisher Scientific, Bremen, Germany) at the Central Science Laboratory (CSL), University of Tasmania. Elemental quantification was performed via external calibration using multi-element calibration solutions (MISA-5, QCD Analysts, Spring Lake, NJ, USA). Samples were introduced to the instrument using an Aridius® II desolvating nebulizer (CETAC Technologies, USA). The DSN was tuned daily, and oxide formation for a range of test analytes (Ba, Ce, U etc) was always less than 0.05%. Raw intensities were blank and dilution corrected.

References
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.
Hatje, V., Bruland, K. W., and Flegal, A. R. (2014). Determination of rare earth elements after pre-concentration using NOBIAS-chelate PA-1®resin: Method development and application in the San Francisco Bay plume. Marine Chemistry, 160, 34–41.
van de Flierdt, T., Pahnke, K., Amakawa, H., Andersson, P., Basak, C., Coles, B., … Yang, J. (2012). GEOTRACES intercalibration of neodymium isotopes and rare earth element concentrations in seawater and suspended particles . Part 1: reproducibility of results for the international intercomparison. Limnology and Oceanography: Methods, 10, 234–251.

Lineage

Progress Code: completed

Statement: Multiple procedural blanks and certified standards were processed and analysed in the same manner as samples. Accuracy and precision of the REE analysis was assessed using the Bermuda Atlantic Time-series Study standard (BATS seawater; (van de Flierdt et al., 2012))
We suspect issues with sample filtration at the CTD stations 9, 16 and 19 of the voyage, with the measurements representing a ‘total’ rather than dissolved fraction.

Notes

Purpose
These data were collected in order to determine rare earth elements concentrations of seawater and for paleo-proxies calibration.