Rare Earth Elements concentrations 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 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.ReferencesArmand, 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.

本数据集的样品采集于南极东缘海域，作业搭载平台为澳大利亚国家海洋设施“调查者号”（R/V Investigator）科考船，采集时段为2017年1月14日至3月5日，航次编号为IN2017_V01，相关研究详见Armand等人2018年的成果。
本次海洋地球科学考察命名为“萨布丽娜海底调查”（Sabrina Sea Floor Survey），核心研究内容为探讨托滕冰川（Totten Glacier）与南大洋在多冰期尺度下的相互作用。

研究人员采用搭载有尼斯金采水器（Niskin® bottle）的CTD采水罗塞塔系统，采集了10升海水样品；随后通过孔径0.45μm的密理博GWSC04510型地下水采样囊式过滤器（Millipore GWSC04510: Ground Water sampling capsule filter），将水样直接过滤至经酸清洗处理的10升聚乙烯塑料桶中。随后在超净工作台内，按照每升水样添加2毫升的6mol/L蒸馏盐酸的比例，将水样酸化至pH=2。

返回位于澳大利亚霍巴特的塔斯马尼亚大学澳大利亚海洋与南极研究所（IMAS）痕量金属实验室后，从大体积海水中分取60mL子样品，参考Hatje等人2014年的方法，使用预装的Nobias® PA1L型螯合树脂柱（日本日立高新技术公司出品）对稀土元素（Rare Earth Elements, REE）进行预富集。预富集后的样品在塔斯马尼亚大学中央科学实验室（CSL）中，采用Element 2型扇形场电感耦合等离子体质谱仪（Sector Field Inductively Coupled Plasma Mass Spectrometer, SF-ICP-MS，赛默飞世尔科技，德国不来梅）测定溶解态稀土元素浓度。元素定量分析采用外标法，使用多元素校准溶液（MISA-5，QCD Analysts公司，美国新泽西州斯普林莱克）完成校准。样品通过Aridius® II型去溶剂雾化器（CETAC Technologies，美国）引入质谱仪。每日对去溶剂雾化系统（DSN）进行调谐，且一系列待测分析物（钡Ba、铈Ce、铀U等）的氧化物产率始终低于0.05%。原始强度数据经过空白校正与稀释倍数校正。

参考文献
1. Armand, L. K., O’Brien, P. E., Armbrecht, L., Baker, H., Caburlotto, A., Connell, T., … Young, A. (2018). 托滕冰川与南大洋多冰期相互作用（IN2017-V01）：航后报告. 澳大利亚国立大学研究出版物（ANU Research Publications）.
2. Hatje, V., Bruland, K. W., Flegal, A. R. (2014). 采用NOBIAS-螯合PA-1®树脂预富集后测定稀土元素：方法开发及其在旧金山湾羽流中的应用. 海洋化学（Marine Chemistry）, 160, 34–41.
3. van de Flierdt, T., Pahnke, K., Amakawa, H., Andersson, P., Basak, C., Coles, B., … Yang, J. (2012). GEOTRACES计划海水与悬浮颗粒物中钕同位素及稀土元素浓度的室间比对 第一部分：国际间比对结果的重现性. 湖沼学与海洋学方法（Limnology and Oceanography: Methods）, 10, 234–251.