中文核心期刊

中国科技核心期刊

CSCD来源期刊

DOAJ 收录

Scopus 收录

胡瑶瑶, 王浩铮, 侯玉杨, 宋皓然. 基于电子探针面扫描定量化的石英闪长岩微区成分分析[J]. 岩矿测试, 2022, 41(2): 260-271. DOI: 10.15898/j.cnki.11-2131/td.202109280132
引用本文: 胡瑶瑶, 王浩铮, 侯玉杨, 宋皓然. 基于电子探针面扫描定量化的石英闪长岩微区成分分析[J]. 岩矿测试, 2022, 41(2): 260-271. DOI: 10.15898/j.cnki.11-2131/td.202109280132
HU Yaoyao, WANG Haozheng, HOU Yuyang, SONG Haoran. A Method for Estimating Micro-area Composition of Quartz-diorite Based on Quantitative Mapping of Electron Probe Microanalysis[J]. Rock and Mineral Analysis, 2022, 41(2): 260-271. DOI: 10.15898/j.cnki.11-2131/td.202109280132
Citation: HU Yaoyao, WANG Haozheng, HOU Yuyang, SONG Haoran. A Method for Estimating Micro-area Composition of Quartz-diorite Based on Quantitative Mapping of Electron Probe Microanalysis[J]. Rock and Mineral Analysis, 2022, 41(2): 260-271. DOI: 10.15898/j.cnki.11-2131/td.202109280132

基于电子探针面扫描定量化的石英闪长岩微区成分分析

A Method for Estimating Micro-area Composition of Quartz-diorite Based on Quantitative Mapping of Electron Probe Microanalysis

  • 摘要: 岩石的微区成分特征是精细化反演岩石演化的重要依据,而常规的电子探针面扫描分析方法无法提供面扫描区域的定量分析结果。本文使用矿物分布相对均匀的代表性岩石样品开展了岩石薄片的面扫描和矿物的定量分析。通过对常规测试的主量元素的面扫描进行图像校正,并利用ZAF校正后的点分析数据与面扫描图像的灰度值进行最小二乘法曲线拟合的方式,实现了X射线强度与质量浓度的转换。对比全岩X射线荧光光谱(XRF)测试数据,电子探针面扫描定量化方法的主量元素SiO2、CaO、FeO、Al2O3、TiO2的相对误差在10%以内,且相对标准偏差(RSD)不高于12%,具有良好的一致性;MgO和Na2O的相对误差与标准偏差略大,可通过多次测量加以改善;K2O由于缺乏富钾硅酸盐矿物的定量分析数据,导致结果不精确。研究表明,在仪器测试条件良好的情况下使用电子探针定量数据校正面扫描图像,可对矿物分布较均匀的岩石开展微区成分分析,给出估计结果,并通过多个切面的多次测量等方式,减少来自矿物形态、粒径大小、分布的影响。

     

    Abstract:
    BACKGROUNDThe estimation of bulk composition of the micro-area of a rock is an important basis of tracing rock evolution. The conventional electron probe microanalysis (EPMA) mapping method cannot provide quantitative analysis results of the surface scanning area.
    OBJECTIVESIn order to estimate the composition of the micro-area by quantitative mapping of EPMA.
    METHODSThe mapping and point analyses were carried out to determine the composition of the micro-area of a homogeneous quartz-diorite. By performing image correction of the pixels of the mapping of the major elements, and using the point analysis data after ZAF correction and the gray value of the surface scan image to perform the least square curve fitting method, the X-ray intensity and concentration were converted.
    RESULTSBy comparing to X-ray fluorescence spectrometry (XRF), the relative errors of SiO2, CaO, FeO, Al2O3 and TiO2 of EPMA method were within 10%, and the relative standard deviation was less than 10%. The relative error and standard deviation of MgO and Na2O were slightly larger, which can be improved by multiple measurements. The K2O content were not accurate due to lack of K-rich silicate minerals' point analysis.
    CONCLUSIONSThe results show that the estimation of micro-area composition of a rock with relatively homogeneous mineral distributions can be carried out by using point analyses of EPMA to correct the mapping under good instrument conditions, and the influence of mineral morphology, particle size, and distribution can be reduced by multiple measurements on different sections.

     

/

返回文章
返回