^(186)锇和^(188)锇双同位素稀释法在辉钼矿铼-锇测年中的应用  

Application of Double Isotope Dilution Technique to Molybdenite Re-Os Geo-chronological Research

作　　者：屈文俊[1] 杜安道[1] 高洪涛[2] 

机构地区：[1]国家地质实验测试中心,北京100037 [2]山东济宁师范专科学校化学系,山东济宁272125

出　　处：《岩矿测试》2000年第4期241-244,共4页Rock and Mineral Analysis

基　　金：原地质矿产部青年地质学家基金资助项目!(97982 3)

摘　　要：以经过负离子热表面电离质谱仪准确标定的1 86Os和1 88Os双同位素作为稀释剂 ,利用1 86Os和1 88Os计算1 87Os的含量 ,能有效地减少用等离子体质谱仪测定1 87Os时由于仪器本身的不稳定性及质量歧视效应所产生的误差 ,使测量准确度比用单同位素作为稀释剂有明显提高。方法应用于辉钼矿Re -Os年龄标准参考物及样品的测定 ,结果与参考值一致 ,5份试样测定的RSD <3%。With neutron induced 186 Os and 188 Os spikes in which Os concentration and abundance composition were evaluated accurately by NTIMS, 187 Os in molybdenite was determined by ICP MS. With two spikes of 186 Os and 188 Os, errors caused by the instability and mass discrimination from ICP MS instrument were diminished and the analytical accuracy was significantly improved. The method has been applied to the molybdenite Re Os geo chronology with satisfactory results. The precision for the determinations of Re Os age is less than 3% RSD( n =5).

关 键 词：锇 双同位素 辉钼矿 铼-锇测年 等离子体质谱仪 

分 类 号：P597[天文地球—地球化学] O657.63[天文地球—地质学]