The characteristics of shale reservoirs on the Yichang Slope in the western Hubei Province were studied using organic geochemistry, mineral X-ray diffraction, field emission scanning electron microscopy and nuclear magnetic resonance methods on black shale samples collected from the Cambrian Shuijingtuo Formation in the well EYY 1. Shale in the study area is mainly composed of quartz, clay minerals and carbonates with high calcium and low siliceous contents. From bottom to top, the contents of clay minerals and carbonates gradually decrease, while the content of quartz gradually increases. Shale porosity has a positive relationship with TOC content, especially in the section with a TOC content higher than 2％. Micro pores and small pores are abundant in the shale. Small pores and meso pores contribute significantly to porosity. The contribution of pores in brittle minerals to the matrix porosity of shale is stable, while the contribution of organic pores and interlayer pores in clay minerals are respectively changing relative to their contents, which means that the contribution of organic pores increases with depth and pores in clay minerals decrease gradually.%以获得重大突破的鄂宜页1井为研究对象,对寒武系水井沱组黑色页岩进行了有机地球化学、矿物X射线衍射、场发射扫描电镜及核磁共振分析等测试,研究了鄂西宜昌斜坡区页岩储层的发育特征.该区页岩主要由黏土矿物、石英和碳酸盐矿物组成,由浅至深表现出黏土矿物和碳酸盐矿物逐渐减少、石英含量逐渐增加的趋势,总体上显示出"高钙低硅"特征;页岩的孔隙度与有机碳含量表现出正相关性,尤其有机碳含量大于2.0％的层段,页岩孔隙度随有机碳升高而增大明显;页岩孔隙以微孔和小孔为主,小孔和中孔对孔隙度贡献明显;页岩中脆性矿物内的孔隙对页岩基质孔隙的贡献稳定,而有机质孔和黏土矿物层间孔隙的贡献与其各自含量变化相关,随深度的增加有机质孔贡献逐渐升高,而黏土矿物层间孔隙贡献逐渐降低.
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