Re-Os同位素定年方法进展及ICP-MS精确定年测试关键技术  

Development of Re-Os isotopic dating analytical technique and determination know-how on ICP-MS precise dating for molybdenite

作　　者：靳新娣[1] 李文君[2] 吴华英[1] 张连昌[1] 杜安道[3] 

机构地区：[1]中国科学院地质与地球物理研究所中国科学院矿产资源研究重点实验室,北京100029 [2]中国地质大学,北京100083 [3]中国地质科学院国家地质实验测试中心,北京100037

出　　处：《岩石学报》2010年第5期1617-1624,共8页Acta Petrologica Sinica

基　　金：国家重点基础研究发展规划项目(2006CB403507);中国科学院地质与地球物理研究所技术支撑项目(11000820)联合资助

摘　　要：本文介绍了Re-Os同位素定年的基本原理、技术发展及应用现状;综述了样品分解和Re-Os分离富集的主要方法,重点对ICP-MS法进行Re-Os同位素定年做了较详尽的介绍,包括质量分馏校正、干扰校正、含量初测、取样量的确定、稀释剂的稀释比及稀释剂加入量等,以确保高精度测试;评述了ICP-MS最常见的测定对象-辉钼矿中Re-Os的失耦现象及降低其对Re-Os同位素定年影响的对策,文中描述了由测定同位素比值计算含量时的误差传递公式并重申了最佳稀释比。最后,指出了Re-Os同位素定年方法研究中应该关注的工作方向。Principles and technical development history,as well as its application of Re-Os dating are presented in this paper.The review focuses on the methods for sample decomposing and Re-Os chemical concentrating and enrichment,especially on determination know-how for ICP-MS Re-Os precise dating,such as mass fractionation and mass interference correcting,concentration predetermining approximately,deciding of sample weight,Re/Os ratio of spike and volume of spike solution and so on.The decoupling of Re and 187 Os on subgrain-scale in molybdenite and strategies for reducing its influence are described.Formula for transmission of error,or the relationship between the change rate for error of concentration and that for error of isotope ratios determined,is exhibited in this paper.It is pointed out that we should pay attention to different directions in study of Re-Os dating method.

关 键 词：RE-OS同位素体系 辉钼矿RE-OS定年 ICP-MS Carius管溶样 成矿时代 

分 类 号：P597.3[天文地球—地球化学]