川南地区下寒武统筇竹寺组是海相页岩气勘探的重要层系之一。前期围绕筇竹寺组黑色页岩的勘探取得了一定的成效,但黑色页岩厚度薄,制约了商业产能的突破。筇竹寺组中粉砂质页岩段气测显示良好,因此,有必要加强对该新层系页岩的系统研究,拓宽非常规页岩气的勘探领域。根据TOC（总有机碳含量）、X射线衍射、薄片、扫描电镜、氦气孔隙度、脉冲渗透率、低温液氮吸附、压汞分析等实验数据,开展对新层系页岩地化特征、岩石学特征、储集空间类型,物性特征、孔隙结构等研究。研究表明新层系页岩储层以粉砂质页岩为主,具有低TOC、高脆性、高孔隙度,较好的孔隙连通性、较高含气性特征。储集空间类型以脆性矿物粒间孔及碳酸盐矿物与长石粒内溶蚀孔为主,仅含少量的有机孔,粉砂级脆性矿物颗粒支撑作用是孔隙保存的关键因素。总体认为,川南筇竹寺组新层系页岩储层具备页岩气勘探的良好储集条件。

The lower Cambrian Qiongzhusi Formation in southern Sichuan is one of the important strata for marine shale gas exploration. In the early stage, the exploration of black shale in Qiongzhusi Formation has achieved certain results, but the thin thickness of black shale restricts the breakthrough of commercial productivity. Silt-shale of Qiongzhusi Formation's gas logging shows high. Therefore, it is necessary to strengthen the systematic research of this new type of shale reservoir and widen the exploration field of unconventional shale gas. Based on the experimental data such asTOC, X-ray diffraction, thin section, SEM, Helium porosity, pulse permeability, Nitrogen adsorption, and mercury intrusion porosimetry, the studies of the geochemical characteristics, petrological characteristics, reservoir space types, physical properties and pore structure of this new type of reservoir have been carried out. The study shows that the new type of shale reservoir is mainly composed of silty shale, which has the property of low TOC, high brittleness, high porosity, good pore connectivity and high gas bearing. The main types of reservoir space are brittle mineral intergranular pores, carbonate minerals and feldspar dissolution intrapores, with only a small amount of organic pores. The support of silty brittle minerals is the key factor for pore preservation. It is generally considered that the new strata of shale reservoirs in Qiongzhusi Formation of southern Sichuan have good reservoir conditions for shale gas exploration.