氢同位素平衡分馏系数α^e与T,M,f间的定量关系  

QUANTITATIVE RELATION OF HYDROGEN ISOTOPE EQUILIBRIUM FRACTIONATION FACTOR α~e WITH T, M AND f

作　　者：钱雅倩[1] 郭吉保[1] 

机构地区：[1]南京地质矿产研究所,南京210016

出　　处：《火山地质与矿产》1997年第4期251-259,共9页Volcanology & Mineral Resources

基　　金：国家自然科学基金!4860069;49273165

摘　　要：氢同位素平衡分馈系数（αe）是氢同位素地球化学研究中必不可少的参数。然而实验测定αe值难度大，周期长，所以还有不少羟基矿物尚无αe值。另外，由于类质同象系列中羟基矿物的化学组成、羟基振动频率等的变化，各矿物的αe值也有所不同，但不可能用实验方法系统地测定类质同象系列中每个矿物的αe值，使氢同位素的应用受到一定影响。本文对αe值与温度（T）、矿物化学组成（M）、羟基振动频率（f）之间的关系作了研究，并得出以下经验方程。非氢键羟基矿物在450－850℃温度范围内，关系式为氢健结构羟基矿物在400℃关系式为：以上关系式对快速、准确获得缺乏αe值的羟基矿物和／或类质同象系列中各矿物的氢同位素分馏方程和分馏系数都是十分有用的。Hydrogen isotope equilibrium fractionation factor (αe) is an indispensable parameter for study of hydrogen isotope geochemistry. As experimental determined αe value is more difficult,some hydroxyl minerals lack αe values yet. In addition, αe value of every mineral that has va-rious chemical compositions and hydroxyl stretching frequency is different in hydroxyl minerals of i-somorphous series, and therefore, it is impossible to determine αe value for every mineral in the isomorphous series by the experiment. As a result, it has influence on application of hydrogen isotope. This paper gave a generalized equation relating 103lnαe with temperature (T), mineral chemical composition (M) and hydroxyl stretching frequency (f) for the systems non-hydro-gen-bonded hydroxyl minerals and water over the temperature range 450 - 850℃ as follows:where M is cation mole factor. And, at 400℃, equation relating 103lnαe to mineral chemical composition (MFe) and hydroxyl stretching frequency (f) for the systems hydrogen-bonded hydroxyl mineralswater is given by These empirical equations a-re much available to estimate hy-drogen isotope fractionation equation and fractionation factor of hydroxyl mineral for absence of αe values and for every mineral in the isomorphous series.

关 键 词：氢同位素 分馏系数 羟基振动频率 化学组成 温度 

分 类 号：P597[天文地球—地球化学] O613.2[天文地球—地质学]