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岩石或矿物中铷和锶的含量可以用X射线荧光光谱、原子吸收光谱、光学发射光谱、质谱、中子活化分析等分析方法进行测定。Flanagan(1976)统计了用各种分析方法测定8个USGS岩石标准样品中铷锶含量的平均值,结果表明,X射线荧光光谱的分析结果,其准确度和精密度虽不及质谱同位素稀释法,但高于光学发射光谱和原子吸收光谱分析法。1976年美国地质调查局(USGS)发行了8个新的岩石标准样品(Flanagan,1976),它们是玄武岩BHVO-1、海洋泥质岩MAG-1、石英安粗岩QLO-1、流纹岩RGM-1、页岩SCO-1、云母片岩SDC-1、页岩SGR-1和正长岩STM-1,这些岩石标准样品又称为USGS-Ⅲ。美国地质调查局是USGS—Ⅲ的发行者,但至今尚未公布这些岩石标准样品的推荐值。Gladney和Goode(1981)以及Abbey(1982)分别发表了USGS-Ⅲ的统计值,尤其是Abbey应用“选择实验室”法给出了可靠程度较高的可用值。
The content of rubidium and strontium in rocks or minerals can be determined by X-ray fluorescence spectrometry, atomic absorption spectroscopy, optical emission spectroscopy, mass spectrometry, neutron activation analysis and other analytical methods. Flanagan (1976) has calculated the average of rubidium and strontium content in eight USGS rock samples by various analytical methods. The results show that although the accuracy and precision of X-ray fluorescence spectrometry analysis are not as good as that of mass spectrometry isotope dilution method, But higher than optical emission spectroscopy and atomic absorption spectrometry. In 1976, the United States Geological Survey (USGS) issued eight new rock standards (Flanagan, 1976), which are basalt BHVO-1, marine mudstone MAG-1, quartz amphibolite QLO-1, rhyolite RGM-1, shale SCO-1, mica schist SDC-1, shale SGR-1 and syenite STM-1. These rock samples are also called USGS-Ⅲ. The US Geological Survey is the publisher of the USGS-III, but so far no recommendations have been published for these rock standards. Gladney and Goode (1981) and Abbey (1982) published statistics for USGS-III, respectively. In particular, Abbey’s “Select Labs” method gave more reliable values.