矿物包裹体的气、液相成分测定

矿物中包裹体温度、压力和气、液相成分的测定数据是阐明矿床成因、成矿物质来源、成矿物质化学条件和成矿元素运移方式等的重要地球化学参数。本文介绍了用载气热爆—气相色谱法测定气相成分(H_2、O_2、N_2、CH_4、CO、CO_2、H_2O)和用超声波提取液相成分,再用原子吸收分光光度计法和数字离子计法分别测定阳离子(K~+、Na~+、Ca~(2+)、Mg~(2+))、阴离子(F~-、Cl~-)。对实验装置、工作条件和分析步骤等本文均有叙述。并以石英标样,对实验结果作了初步讨论。其中对气相成分的提取,用载气热爆法代替真空热爆法可提高工作效率五倍。

DETERMINATION OF GAS AND LIQUID COMPONENTS OF INCLUSION IN MINERALS

The data of temperature, pressure and gas and liquid composition of inclusion in minerals are important geochemical parameters for learning the genesis of ore deposits, origin of ore-forming materials, minerogenetic physical-chemical conditions and transporting way of ore-forming elements. The authors have done test study of analysis method for determination of gas and liquid composition of inclusion in minerals.In this paper, the gas components (H_2, O_2, N_2, CH_4, CO, CO_2, H_2O) were determinated with carrier heating decrepitation-gas chromatography. A sample is set in the quartz tube and removed second inclusion in it. Then, the gas components of primary inclusion are, with hydrogen as carrier, once for all, put into gas chromatograph for determination, when they are all free. The lowest limit of detectability is (ppm) 1.2 for H_2O, 0.8 for CO_2, 0.002 for H_2, 0.05 for CH_4, 0.26 for N_2, 0.2 for O_2, 0.27 for CO. To replace vaccum heating decrepitation with carrier heating decrepitation is the character of this determination and can raise working efficient for five times.The liquid components (K~+, Na~+, Ca~(2+), Mg~(2+), F~-, Cl~-) were determinated with following steps. At first the liquid components are picked up with ultrasonic wave. The test shows the optimum conditions for the operation being 170W in power and 60min in time. Then atomic absorption spectrophotometry and ionselective electrode are used for determination of cation and anion. The lowest limit of detectability is (ppm) 0.06 for Na~+, 0.15 for K~+, 0.2 for Ca~(2+), 0.02 for Mg~(2+) and 0.2 for F~-, 3.5 for Cl~-.At last, the paper describs the analysis of type sample of quartz and discusses preliminarily the result of this test.