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对湖北秭归县五龙剖面五峰组—龙马溪组下段黑色岩系的微量元素和有机碳含量进行了系统采样分析,结果表明,U/Th、Ni/Co、V/Cr和V/Sc比值等判别指标能够很好的响应各时期氧化还原条件和海平面的变化,对奥陶系—志留系界线附近的地层缺失也有明显的指示作用。另外,U/Th、Ni/Co、V/Cr和V/Sc比值与TOC值之间表现出良好的正相关关系,表明这些古环境判别指标在一定程度上可用来指示五峰组和龙马溪组的有机碳含量变化。通过对五龙剖面及周边地区富有机质页岩厚度、TOC值和含气性的对比分析,推断五龙地区和西侧的鼓锣坪地区、东侧的九畹溪地区构成隆凹相间的格局,这一认识对区域内的页岩气有利目标区预测具有一定的指导意义。
The results show that U / Th, Ni / Co, V / Cr and V / Sc ratios etc. are systematically sampled from the black rock series in the lower part of the Wufeng-Longmaxi Formation in Wulong County, Hubei Province The discriminant index can well respond to the redox conditions and sea level changes in each period, and also has a clear indication of the absence of strata near the Ordovician-Silurian boundary. In addition, there is a good positive correlation between U / Th, Ni / Co, V / Cr and V / Sc ratios and TOC values, indicating that these paleoenvironmental discriminant indexes can be used to indicate Wufang formation and Longmaxi formation Organic carbon content changes. By comparing the thickness, TOC and gas-bearing of organic-rich shale in the Wulong section and the surrounding area, it is inferred that the composition of the Longlou and the Gulou area in the Wulongping area and the Gulongping area in the Wulong area and the west and the Jiuyi stream area in the east This understanding has certain guiding significance for the prediction of the favorable target area of shale gas in the region.