【摘要】 黄铁矿等硫化物离子探针硫同位素分析已经广泛应用在成矿机理、古环境重建、大气环境硫源示踪及行星演化等研究中。纳米离子探针(CAMECA Nano SIMS 50L)的使用将硫化物硫同位素分析空间分辨率提升到微纳尺度(1μm～100nm),实现了分辨率1～2μm、精度0.5‰(1SD)的硫同位素点分析方法，分辨率100nm、精度1‰的硫同位素图像分析方法。为了进一步优化分析流程拓展纳米离子探针硫同位素的应用，本文系统比较了纳米离子探针微纳尺度硫同位素点分析方法、图像分析方法的各自特点及分析流程；并以东营凹陷北带沙四段黄铁矿为研究对象，联合采用了纳米离子探针硫同位素点分析和硫同位素图像分析手段，对黄铁矿微细结构进行分析，从而揭示了储层中黄铁矿成因及其油气成藏的指示意义。更多还原

【Abstract】 Secondary Ion Mass Spectrometry(SIMS) has been widely applied to in situ sulfur isotopic analysis for the study of mineralization mechanisms, paleoenvironmental reconstruction, atmospheric sulfur source tracing and planetary evolution. The application of nano scale SIMS(CAMECA Nano SIMS 50L) has achieved the sulfur isotope spot analysis method with a spatial resolution of 1～2μm. Thus, sufficient signal amount cannot be achieved due to limited analytical depths, resulting in low analytical precision(1.5‰). Recently, we report a new method that simultaneously improves spatial resolution and precision of sulfur isotopic analysis based on the NanoSIMS imaging mode. This method uses a long acquisition time(e.g., 3h) for each analytical area to obtain sufficient signal amount. The optimal spatial resolution of ～100nm for sulfur isotopic analysis can be implemented with an analytical precision of ～1‰(1SD). In order to further optimize the analysis process to extend the application of Nano SIMS sulfur isotopic analytical method, this study systematically compares the characteristics and analysis process of NanoSIMS sulfur isotopic spot analytical methods and imaging analysis methods. We then applied the above methods to study pyrites in the Dongying Depression. Sub-micron sulfur isotopic variations were observed, which were used to reveal the genesis of pyrite in the reservoir and yield implications for oil charging.更多还原