手持式X射线荧光光谱多点测试技术在地质岩心和岩石标本预研究中的应用

目前国内外比较先进的岩心无损测试,主要采用高光谱技术及XRF扫描技术,这两种扫描范围较大的快速分析方法,均存在着精度要求越高测试时间越长、完整岩心数据精度较高、不完整岩心及岩石标本数据精度较差的问题,难以满足馆藏地质标本取样范围小、快速、准确的要求。本文应用手持式X射线荧光光谱分析技术,以多点测试加权平均的计算方法,改善复杂的样品岩性、矿物种类等因素的影响,提高了分析结果的准确性。结果表明:本方法与定量分析结果比较,具有指示半定量范围作用的测试结果超过82%,加权平均值比算术平均值的指示效果提高了近22%,多点测试的准确度得到了明显提高。并且,该方法具有测试元素较多、粗糙标本经微处理后便可随时测试等优点,较好地解决了馆藏地质标本取样的应用问题。通过这次预研究,新发现了部分铅锌矿标本银元素含量较高、Zk0901钻孔(黄沙坪矿区)168.46~171.24 m的Mo元素平均值为0.3%等具有实际意义的研究数据,为馆藏地质标本再利用提供了重要的找矿信息。

Application of P-XRF Multi-point Analysis Technique in Pre-research of Geological Core and Rock Specimens

Internationally, two advanced nondestructive methods of drill core testing include hyperspectral technology and XRF scanning technology. Both methods include problems that the higher the accuracy requirements, the higher the accuracy of the complete core data, the less accurate data of the incomplete core and rock specimen, and the difficulty of satisfying fast and accurate requirements of small sampling areas of the geological samples. Portable X-ray Fluorescence Spectrometry (P-XRF) was used for the study described in this paper. The weighted average of the multi-point test method reduces the influence of complex sample lithology and mineral species and improves the accuracy of this method. Compared with quantitative analysis, the results with a semi-quantitative range indicator role are more than 82%. The weighted average is nearly 22% higher than the arithmetic mean, and thus the accuracy of the multi-point test is improved significantly. Furthermore, the method can be used to analyze more elements after the rough processing of specimens, which better solves the sampling problem of specimens in the geological cores and samples library. Through this pre-research, it is found that silver content is higher in some specimens of lead-zinc mine and Mo content is 0.3% in the 168.46-171.24 m position of drilling core Zk0901. This study provides important prospecting information for the reuse of the specimens in the geological cores and samples library.