A rapid single column separation scheme for high-precision Sr-Nd-Pb isotopic analysis in geological samples using thermal ionization mass spectrometry

作者：Li, Chao-Feng^*; Chu, Zhu-Yin; Guo, Jing-Hui; Li, You-Lian; Yang, Yue-Heng; Li, Xiang-Hui

来源：Analytical Methods, 2015, 7(11): 4793-4802.

DOI：10.1039/c4ay02896a

• RARE-EARTH-ELEMENTS
• MC-ICP-MS
• MINIATURIZED EXTRACTION CHROMATOGRAPHY
• ROCK REFERENCE SAMPLES
• SEQUENTIAL SEPARATION
• DOUBLE SPIKE
• LEAD
• RATIOS
• SM
• STRONTIUM

Thermal ionization mass spectrometry (TIMS) is considered the most accurate technique for determining Sr-Nd-Pb isotopic ratios in geological samples. However, time-consuming and complex sample separation procedures greatly hinder the instrumental measurement efficiency. In this study, a single-column separation chemistry procedure for Sr-Nd-Pb from single rock dissolution was developed. The chemistry procedure was designed to minimize the number of evaporation steps and considerably shorten the separation time, enabling high throughput for TIMS. In contrast to conventional three-column separation procedures (similar to 3 days), this technique was characterized by high efficiency superiority in terms of separation time (similar to 8 hours), a 3-fold enhancement in the separation efficiency. The stability of our procedure was demonstrated by replicated TIMS measurements of Sr-87/Sr-86, Nd-143/Nd-144, Pb-206/Pb-204, Pb-207/Pb-204 and Pb-208/Pb-204 ratios for six international silicate rock reference materials, spanning a wide range of bulk compositions. The analytical results obtained for these standards agreed well with published data. The external reproducibility (2 RSD, n = 10) of a BCR-2 standard sample was +/- 0.0020% for Sr-87/Sr-86, +/- 0.0023% for Nd-143/Nd-144, and +/- 0.021-0.033% for Pb-206/Pb-204, Pb-207/Pb-204 and Pb-208/Pb-204 ratios.

• 出版日期2015
• 单位岩石圈演化国家重点实验室; 中国科学院地质与地球物理研究所兰州油气资源研究中心; 中国科学院地质与地球物理研究所