原位能量色散X射线荧光现场分析岩样矿物成分时, 岩样基体效应会对测量结果产生影响。 本文以Cu元素作为待测元素, 研究了17种不同岩样基体对原位能量色散X射线荧光分析Cu元素特征X射线强度的影响及其修正方法。 采用蒙特卡罗方法模拟获得了Cu元素含量相同的17种不同岩样测量谱线, 综合各类岩石元素构成的相似性, 并依据模拟谱线Cu元素Kα射线强度与谱线参数之间的相关性, 反映了原位能量色散X射线荧光分析岩样Cu元素的基体效应并不完全受岩体元素构成或岩石分类的控制, 需要依据岩石样分析谱线参数的相关性进行归类讨论。 针对基体影响Cu元素特征射线强度相似的15种岩样进一步研究, 并对Cu元素特征X射线与谱线主要参数的主成分进行分析, 发现散射本底、 X光管靶材料特征X射线及其非相干散射峰强度能够很好的描述Cu元素特征X射线强度受岩样基体影响的变化, 据此可以对基体效应影响相似的岩体进行Cu元素测量结果修正。 采用本文方法同样也能为不同岩性岩体其他待测元素基体效应的修正提供参考。

The mineral constituents of the rock sample can be analyzed with in-situ energy dispersive X-ray fluorescence analysis technology (In-situ EDXRF), the matrix effect of rock sample will effects on measurement results. The Monte Carlo simulation method is used to conduct fluorescence analysis spectrum with ideal measurement conditions, which provides analytical data for matrix effect research. The measured spectrum of seventeen kinds rock samples are being simulated, which has the same Cu content. Therefore, the influences with matrix effect of rock sample in in-situ EDXRF take Cu element for example. Based on correlation between Cu Kα X-ray intensity and spectral parameters, considering elements similarity of all kinds rock samples, it is found that the variation the Cu Kα X-ray intensity not only by the control of rock elements composition or rock classification. The matrix effect of rock samples must be classified according correlation between Cu Kα X-ray intensity and spectral parameters. After the matrix effect classification, fifteen kinds of rock samples, which belong to the same matrix effect, can be corrected more effective. Based on principal component analysis of similar matrix effect rock samples, it is found that the scattering background, target element K-series X-ray of X-ray tube and its incoherent scatter intensity can be a good description of Cu Kα X-ray intensity which is affected by rock matrix, thus it can be used to correct the Cu element measurement results. Certainly, this technology can also provide reference for matrix effect correction to other elements in rock.