重稀土-钒-铝硅酸盐矿物电子探针定量分析  

Electron Probe Quantitative Analysis of HREE-V-Aluminosilicate Minerals

作　　者：张文兰[1] 胡欢 刘鹏 陈小丹 ZHANG Wenlan;HU Huan;LIU Peng;CHEN Xiaodan(State Key Laboratory for Mineral Deposits Research,School of Earth Sciences and Engineering,Nanjing University,Nanjing 210023,China;State Key Laboratory of Continental Dynamics,Department of Geology,Northwest University,Xi’an 710069,China;Key Laboratory of Metallogeny and Mineral Assessment,Ministry of Natural Resources/Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100037,China)

机构地区：[1]南京大学内生金属矿床成矿作用研究国家重点实验室,南京大学地球科学与工程学院,江苏南京210023 [2]西北大学地质学系,大陆动力学国家重点实验室,陕西西安710069 [3]自然资源部成矿作用与资源评价重点实验室,中国地质科学院矿产资源研究所,北京100037

出　　处：《岩矿测试》2022年第5期754-763,共10页Rock and Mineral Analysis

基　　金：中国科学院地质与地球物理研究所重点部署项目(IGGCAS-201901)。

摘　　要：产自广东省梅州市玉水铜矿的景文矿,属于含水、重稀土-矾-铝硅酸盐矿物(简写为HREE-V-铝硅酸盐矿物),其化学结构式为Y_(2)Al_(2)V_(2)^(4+)(SiO_(4))_(2)O_(4)(OH)_(4),该矿物在全球属首次发现,暂未开展相关研究。相对于含轻稀土矿物,含重稀土矿物在电子探针分析过程中,当被高压电子束轰击时,被激发出来的特征X射线线系繁多,线系之间分布更加密集,彼此之间相互重叠的现象也更为严重,要获得理想数据的难度很大,是亟待解决和突破的技术难题。本文对该矿物进行了精细的电子探针定量分析,获得理想的化学成分数据,为新矿物命名提供了理论数据技术支撑。通过对实验方法的探索和总结获得以下结果:①利用15kV加速电压、100nA束流对试样进行全元素扫描,以此确定出17种元素;②在定量分析过程中,对重叠峰进行了剥离;③利用仪器软件中的Zoom-Peak ID程序,选择出17种元素的分析线系、精确的峰位及上下背景值;④选取合适的标样及测试时间等定量分析条件,最终获得理想的定量分析结果(平均总量97.41wt%)。上述四条也是确保获得理想定量分析数据的关键因素。BACKGROUND:Jingwenite,Y_(2)Al_(2)V_(2)^(4+)(SiO_(4))_(2)O_(4)(OH_(4)),from Yushui Copper Mine,Meizhou City,Guangdong Province,is a type of HREE-V hydrated aluminosilicate minerals.Since its discovery,no research has been done.During electron probe microanalysis(EPMA)for HREE minerals,many characteristic X-ray lines are excited when samples are bombarded by a high-voltage electron beam.The lines are not only numerous,but also seriously overlap with each other.It is very difficult to obtain optimal data,and it is a technical problem that needs to be solved.OBJECTIVES:To obtain ideal chemical composition data by fine quantitative analysis of the mineral by EPMA to provide theoretical data technical support for the naming of the new mineral.METHODS:Full element wave spectrum scanning for Jingwenite by JEOL JXA-8530F Plus.RESULTS:(1)17 elements were identified by wave dispersive scanning with an accelerating voltage of 15kV and a beam current of 100nA;(2)Stripping overlapped peak during the quantitative analysis;(3)Peak positions,upper and lower background values of 17 elements were set by Zoom-Peak ID program in quantitative analysis;(4)The ideal quantitative analysis results(total 97.41wt%)were obtained by selecting appropriate standard samples and testing dwell time.CONCLUSIONS:The above four items are key factors to ensure ideal quantitative analysis data.

关 键 词：HREE矿物 电子探针 分析条件 线系干扰 重叠峰剥离 

分 类 号：P575.1[天文地球—矿物学]