玄武岩中铅同位素和微量铀钍铅的测定  

Determination of Pb Isotopic Ratios and Trace U,Th,Pb Concentration of Basalts

作　　者：彭子成[1] Lorretta Kwak Peng Zicheng;Lorretta Kwak

机构地区：[1]中国科技大学 [2]美国地质调查所同位素地质部,科罗拉多州

出　　处：《岩矿测试》1986年第2期121-124,I0006,共5页Rock and Mineral Analysis

摘　　要：近10年来国外对基性玄武岩的铅同位素和U/Pb、Th/Pb、Th/U的研究已十分活跃。通过对这些同位素和微量元素的分析,可以对来自不同构造背景的玄武岩,如海岭的拉斑玄武岩、海岛的碱性玄武岩、岛弧的高铝玄武岩、以及大陆的拉斑、碱性、强碱性玄武岩的岩浆来源。The chemical procedures for determining the isotopic compositions of Pb and trace U,Th,Pb concentration of basalts from Eastern China were introduced in this paper.Samples were dissolved in HNO_(3)-HF-HClO_(4) and separated by AG 1×8(Cl^(-))and AG 1×8(NO_(3)^(-))resin columns.With the aim at gaining the high purity and yield of U,Th,Pb compounds,all chemical reagents used must be purified. The average values of 5 repeat determinations of U. S. Standard BCR-1 are 18.813±0.005 for ^(206)Pb/^(204)Pb, 15.630±0.003 for ^(207)Pb/^(204)Pb, 38.709 ± 0.017 for ^(208)Pb/^(204)Pb;whereas U, Th, Pb concentration are 1.70±0.01, 5.91± 0.04, 13.46±0.12, respectively. The procedures are also suitable for analyzing chondrites, granites and andesites. Even for kimberlites, after dissolving the samples with Krogh bomb the isotopic ratios of U, Th, Pb can also be measured by above-mentioned procedures.

关 键 词：铅同位素 碱性玄武岩 拉斑玄武岩 高铝玄武岩 岩浆来源 微量元素 基性 铀钍 

分 类 号：P58[天文地球—岩石学]