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利用X射线衍射和扫描电子显微镜及能谱仪开展了岩石特征、矿物组成、微观结构特征和元素与矿物成分分析，研究了中上扬子地区五峰组-龙马溪组下段富有机质硅质页岩的成因及其与页岩气富集的关系。五峰组和龙马溪组下段硅质页岩中的脆性矿物石英含量较高，多在45%以上，最高达88%，而黏土矿物含量较低；少数页岩样品黏土矿物含量较高，同时碳酸盐矿物含量也较高，石英含量则较低。显微镜下发现富含石英的硅质页岩中大多存在大量团块状生物碎屑，并作为骨架颗粒与其他矿物基质胶结在一起，结构致密，而富含黏土矿物的页岩则多具水平层理和纹层理，未见明显的生物碎屑。进一步的显微分析发现，富含石英的硅质页岩中的生物碎屑具有清晰的外形轮廓和圈层状生长结构及放射状针刺结构，显示出明显的硅质生物放射虫的形貌特征，且主要由硅和氧两种元素组成的能谱分析结果证实了确属放射虫无疑。多种元素的面分布特征进一步反映出陆源物质的输入较少，而且海底的热液活动也极为有限，指示页岩中硅质主要来源于放射虫生物骨架，为该段硅质页岩的生物成因提供了充分证据。放射虫大量发育的基本条件是海水中营养元素-溶解态硅的富集，浮游藻类在该环境下易于大量勃发，高的初级生产力条件为硅质页岩中有机质的富集奠定了重要物质基础。放射虫成因的硅质页岩还有利于页岩中原生无机孔隙和次生有机孔隙的保持和保存，对页岩气的富集有极为重要的控制作用。
The rock characteristics, mineral composition, microstructure characteristics and elemental and mineral composition of the rocks were analyzed by X-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy. The organic-rich siliceous shale in the lower part of the Wufeng Formation-Longmaxi Formation in the Middle-Upper Yangtze region was studied. Genesis and its relationship with shale gas enrichment. The fossil minerals in the siliceous shale in the lower part of Wufeng Formation and Longmaxi Formation have higher quartz content, more than 45% and up to 88%, while the content of clay minerals is relatively low. The content of clay minerals in the few shale samples is high, Salt mineral content is higher, the quartz content is lower. Microscopically, most of the quartz-rich siliceous shale is found to contain a large number of clumps of biological debris, which are cemented together with other mineral matrices as structural grains and have a dense structure, while clay-rich shale has more horizontal layers Li and texture layering, no obvious biological debris. Further microanalysis revealed that the bioclastic in quartz-rich siliceous shale has a clear outline of the shape and the lamellar growth structure and radial acupuncture structure, showing the morphological features of the siliceous bio-radiolarian , And the result of energy spectrum analysis mainly composed of two elements of silicon and oxygen confirmed that there is no doubt that it belongs to radioactive insects. The multi-element surface distribution further reflects the less input of terrigenous materials and the hydrothermal activity on the seabed is extremely limited, indicating that the siliceous in shale is mainly derived from the radiolarian biological framework, Genesis provided sufficient evidence. The basic conditions for the large-scale development of radiolarians are the enrichment of nutrient elements in the seawater - dissolved silicon. Planktonic algae bloom easily in this environment, and high primary productivity conditions lay an important material foundation for the enrichment of organic matter in siliceous shale . Radiolarian silica shale is also beneficial to the preservation and preservation of primary inorganic and secondary organic pores in shale, and plays an important role in controlling shale gas enrichment.