Stammeier Jessica A, Nebel Oliver, Hippler Dorothee, Dietzel Martin
Institute of Applied Geosciences, Graz University of Technology, Rechbauerstraße 12, 8010 Graz, Austria.
GFZ German Research Centre for Geosciences, Telegrafenberg, 14473 Potsdam, Germany.
MethodsX. 2020 Mar 3;7:100847. doi: 10.1016/j.mex.2020.100847. eCollection 2020.
We undertook Sr/Sr analyses for a range of carbonate bearing geological reference materials, and combined these with δMg for a subset of samples. Following chemical purification in a series of chromatographic extractions, isotope ratios were measured by Multi-Collector-ICP-MS using a Plasma II (Nu instruments, Wrexham, UK). To validate efficient sample digestion procedures of carbonate fractions, total samples were treated with either 3 mol l HNO and 0.5 mol l HCl, respectively. Results of both leaching procedures are identical within reproducibility. Reference values for SRM 88A (formerly NBS 88A), SRM 1B (formerly NBS 1B), SARM 40, SARM 43, JDo-1, JLs-1, and San Carlos olivine range from 0.70292 to 0.73724 in Sr/Sr and from -2.80 to -0.41 ‰ for δMg, respectively. This set of geological reference materials can be used for sedimentary rock material with different carbonate mineral and matrix composition as quality control measurements of combined stable Mg and radiogenic Sr isotope analyses.•We present a protocol that facilitates the chemical separation of Mg and Sr in carbonate bearing geological reference materials including Sr/Sr and δMg of certified reference materials.
我们对一系列含碳酸盐的地质参考物质进行了锶同位素比值（Sr/Sr）分析，并将其中一部分样品的分析结果与镁同位素比值（δMg）相结合。在经过一系列色谱萃取进行化学提纯后，使用英国雷克瑟姆的Nu仪器公司生产的Plasma II型多接收电感耦合等离子体质谱仪（Multi-Collector-ICP-MS）测量同位素比值。为验证碳酸盐组分高效的样品消解程序，分别用3mol/L硝酸和0.5mol/L盐酸处理全部样品。两种浸出程序的结果在重现性范围内是相同的。标准参考物质88A（原NBS 88A）、1B（原NBS 1B）、SARM 40、SARM 43、JDo-1、JLs-1和圣卡洛斯橄榄石的Sr/Sr参考值范围为0.70292至0.73724，δMg参考值范围为-2.80至-0.41‰。这套地质参考物质可用于具有不同碳酸盐矿物和基质组成的沉积岩材料，作为稳定镁和放射性锶同位素联合分析的质量控制测量标准。•我们提出了一种方案，该方案有助于在含碳酸盐的地质参考物质中进行镁和锶的化学分离，包括标准参考物质的Sr/Sr和δMg。
