X射线荧光测定低量铷、锶及其应用  

XRF DETERMINATION OF TRACE Rb AND Sr IN GEOLOGICAL MATERIALS AND ITS APPLICATION IN GEOCHRONOLOGY

作　　者：甘璇玑 吴莹莹 肖德明[1] 

机构地区：[1]北京铀矿地质研究所

出　　处：《地球化学》1985年第3期283-292,共10页Geochimica

摘　　要：岩石或矿物的铷、锶等时线年龄，除进行Rb／Sr比值的草测外，必须准确测定样品中^87Sr/^86Sr和^87Rb/^86Sr的比值。前者可直接由质谱测定，也可用稀释法质谱测定值计算而得；后者一般用同位素稀释法测定^87Rb及^86Sr。本方法是用质谱直接测定町^87Sr/^86Sr比值，而^87Rb／^86Sr比值则由X射线荧光光谱法测定了Rb／Sr重量比之后，按下式计算获得：A procedure is described in the present paper for XEF determination of trace Rb and Sr in geological samples. The results obtained from 12 geochemical reference sam-ples (USGS) and 6 geochemical reference samples (BMR Australia) are in good agre-ement with those reported recently. The variation of determined Rb/Sr ratios is less than 1% in the case of Rb or Sr>30 ppm.XRF determination combined with simple isotopic measurement (87Sr/86Sr) makes it possible to calculate radiometric ages. In our practice this method has proved to have the same accuracy and precision as the isotope dilution method in Rb-Sr geochronology.

关 键 词：X射线荧光测定 铷 锶 等时线年龄 质谱分析 

分 类 号：P597.3[天文地球—地球化学] O657.34[天文地球—地质学]