泰思肯集成矿物分析仪对岩矿样品精细扫描中不同实验条件的对比研究

Comparative study on different analytical conditions in fine scanning of rocks and minerals by TESCAN Integrated Mineral Analyzer

泰思肯集成矿物分析仪(TESCAN Integrated Mineral Analyzer,简称TIMA)是基于扫描电子显微镜、加载多个X射线能谱仪和其他探测器、自动识别矿物并成像的分析系统。TIMA已广泛应用到岩石学、矿物学、地球化学、石油、古生物等地球科学领域中,特别是在针对矿物成分和结构复杂、粒径细小的地质样品以及数量大且样品重复性高的实验需求时,它具备分析快速并且能获得统计学数据的优势。为了达到分析测试目的,同时节约成本,选择最佳的实验条件至关重要,但相关研究往往被忽视。因此,本文以陕西省略阳县铧厂沟金矿床中的含金矿化黄铁绢英岩样品为例,使用TIMA在不同扫描模式和分析类型以及多种实验参数设置条件下,对样品进行了分析测试,比较了测试结果的矿物相组成数据、小区域矿物相图和元素分布图的图像质量以及矿物颗粒粒径等统计数据。研究结果表明,影响TIMA分析质量的主要因素为背散射像素间距、能谱测试点间距以及X射线采集计数;实验条件的选择主要取决于样品的矿物成分、粒径和测试分析的目的。

TESCAN Integrated Mineral Analyzer(TIMA)is an analysis system based on a scanning electron microscope that incorporates multiple X-ray spectrometers and other detectors.It could automatically identify minerals and produce images.TIMA has been widely applied in earth sciences,including petrology,mineralogy,geochemistry,petroleum,and paleontology,particularly in the rapid analysis of some geological samples with complex mineral composition and structure and small grain size,and a large number of repetitive samples to obtain statistical data for research purposes.In order to achieve the goals of analysis and save costs,it is crucial to select the optimal analytical conditions,but this aspect is often overlooked.This article takes sample of gold-bearing pyrite-sericite-quartz altered rock from the Huachanggou gold deposit in Lueyang County,Shaanxi Province,as an example.Using TIMA,the samples were analyzed under different scanning modes,analysis types,and various experimental parameter settings.The study compared the mineral phase composition data,image quality of mineral phase maps and elemental distribution maps in a small field,as well as statistical data such as mineral grain size.The results indicate that the main factors influencing the quality of TIMA analysis are the backscattered electron(BSE)pixel spacing,energy-dispersive X-ray spectroscopy(EDS)test dot spacing,and X-ray acquisition counts.The selection of analytical conditions primarily depends on the mineral composition,mineral grain size,and the purpose of the analysis.