Barium Isotopic Compositions in Thirty-Four Geological Reference Materials Analysed by MC-ICP-MS
Barium Isotopic Compositions in Thirty-Four Geological Reference Materials Analysed by MC-ICP-MS
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MC-ICP-MS 分析 34 种地质标准物质中的钡同位素组成
DOI：
10.1111/ggr.12299
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发表时间：
2019-11-13
影响因子：
3.8
通讯作者：
Zhang, Zhao-Feng
中科院分区：
文献类型：
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作者：
An, Ya-Jun;Li, Xin;Zhang, Zhao-Feng
实验室间数据比较需要测量广泛使用的参考材料的 Ba 同位素比率。在这里，我们提供了 34 种地质参考材料的新 Ba 同位素数据，包括硅酸盐、碳酸盐、河流/海洋沉积物和土壤。这些参考材料（RM）涵盖了广泛的成分，其中Ba质量分数范围为6.4至1900μg g（-1），SiO2范围为0.62％至90.36％m/m，MgO范围为0.08％至41.03％m/m。我们的数据的准确性和精密度是通过重复样本和美国地质调查局岩石 RM 的分析来评估的。所有 RM 的钡同位素组成在不确定范围内彼此一致。这些 RM 中 Delta Ba-138/134 的变异高达千分之 0.7。页岩参考样品受高度化学风化影响，具有最高的 Delta Ba-138/134（0.37 +/- 0.03 ppm），而从排水碳酸盐岩支流中获得的河流沉积物的 Delta Ba-138/134 最低（-0.30 +/- 0.05 ppm）。地球化学 RM 在高精度、准确测定具有相似基质的天然样品的 Ba 同位素组成方面发挥着基础作用。对这些 RM 的分析可以为 Ba 同位素数据提供普遍的可比性，并能够评估实验室间数据的准确性。
Measurement of Ba isotope ratios of widely available reference materials is required for interlaboratory comparison of data. Here, we present new Ba isotope data for thirty-four geological reference materials, including silicates, carbonates, river/marine sediments and soils. These reference materials (RMs) cover a wide range of compositions, with Ba mass fractions ranging from 6.4 to 1900 mu g g(-1), SiO2 from 0.62% to 90.36% m/m and MgO from 0.08% to 41.03% m/m. Accuracy and precision of our data were assessed by the analyses of duplicate samples and USGS rock RMs. Barium isotopic compositions for all RMs were in agreement with each other within uncertainty. The variation of delta Ba-138/134 in these RMs was up to 0.7 parts per thousand. The shale reference sample, affected by a high degree of chemical weathering, had the highest delta Ba-138/134 (0.37 +/- 0.03 parts per thousand), while the stream sediment obtained from a tributary draining carbonate rocks was characterised by the lowest delta Ba-138/134 (-0.30 +/- 0.05 parts per thousand). Geochemical RMs play a fundamental role in the high-precision and accurate determination of Ba isotopic compositions for natural samples with similar matrices. Analyses of these RMs could provide universal comparability for Ba isotope data and enable assessment of accuracy for interlaboratory data.