A routine high-precision method for Lu-Hf isotope geochemistry and chronology
A routine high-precision method for Lu-Hf isotope geochemistry and chronology
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DOI：
10.1007/bf01166766
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发表时间：
1981-09
影响因子：
3.5
通讯作者：
P. Patchett;M. Tatsumoto
中科院分区：
文献类型：
--
作者：
P. Patchett;M. Tatsumoto
本文介绍了一种从岩石、陨石和矿物样品中化学分离Lu和Hf的方法，以及一种改进的Hf质谱运行技术。这使得（i）使用176 Lu → 176 Hf +β−衰变方案进行地质和宇宙年代学研究，以及（ii）地球和月球中行星过程的地球化学研究成为可能。Lu和Hf的化学空白<0.2 ng。从1 μg Hf开始，总离子电流为0.5×10− 11安培，可维持3-5小时，176 Hf/177 Hf比率的精度为0.01-0.03%。采用~（179）Hf/~（177）Hf =0.7325的标准化方法，给出了约翰逊-万泰Hf标准样品JMC 475的大量结果，并敦促将该样品作为国际质谱标准样品;从丹佛提供的一批JMC 475中制备的合适的等分试样，给出了标准岩石BCR-1和JB-1的Lu-Hf分析。评价了Lu-Hf方法在同位素地球化学中的应用潜力。
A method for chemical separation of Lu and Hf from rock, meteorite and mineral samples is described, together with a much improved mass spectrometric running technique for Hf. This allows (i) geo- and cosmochronology using the176Lu→176Hf+β−decay scheme, and (ii) geochemical studies of planetary processes in the earth and moon.Chemical yields for the three-stage ion-exchange column procedure average 90% for Hf. Chemical blanks are <0.2 ng for Lu and Hf. From 1 μg of Hf, a total ion current of 0.5×10−11Ampere can be maintained for 3–5 h, yielding 0.01–0.03% precision on the ratio176Hf/177Hf. Normalisation to179Hf/177Hf=0.7325 is used.Extensive results for the Johnson Matthey Hf standard JMC 475 are presented, and this sample is urged as an international mass spectrometric standard; suitable aliquots, prepared from a single batch of JMC 475, are available from Denver.Lu-Hf analyses of the standard rocks BCR-1 and JB-1 are given. The potential of the Lu-Hf method in isotope geochemistry is assessed.