This paper takes the deep sandstone of Bayingebi Formation in Guaizihu Sag of Yin’e Basin as the research object. Based on the basic characteristics of the reservoir, this article uses the constant rate mercury intrusion method to distinguish pores and throats and quantitatively characterize the characteristic parameters of pores and throats. Combined with scanning electron microscopy and casting thin section method, the morphological characteristics of pores and throats are qualitatively characterized, and the differences in microscopic pore structure are analyzed. In addition, different pore types are classified according to the fractal dimension of pore throat, and the main factors affecting the development of reservoir pores are discussed. The results show that the reservoir rock types in this area are mainly feldspar lithic sandstone with low compositional maturity. The average porosity of sandstone reservoir in the study area is 10.8%, and the average permeability is 1.17 mD, which belongs to low porosity and ultra-low permeability reservoir. Reservoir space types are mainly primary intergranular pores, dissolution pores and microfractures. The average pore radius is 195 μm, and the average throat radius is 3.5 μm. The pore structure types of the reservoir are divided into micro pore small throat type, small pore small throat type and large pore coarse throat type. The study area generally has the characteristics of relatively large pore-throat ratio, good pore-throat configuration relationship is an important factor affecting reservoir physical properties, and the main controlling factors affecting pore development are the combined effects of early diagenesis, organic acid dissolution and hydrocarbon filling. After relatively weak compaction and cementation transformation, the original debris provides a material and spatial basis for later dissolution, and the thick organic-rich mudstone at the top and bottom of the reservoir provides a source of organic acid dissolution and hydrocarbon filling. 

以银额盆地拐子湖凹陷巴音戈壁组深层砂岩为研究对象, 在探究储层基本特征的基础上, 采用恒速压汞法区分孔隙与喉道, 定量地表征孔喉特征参数; 通过扫描电子显微镜和铸体薄片, 定性地表征孔喉形态特征, 分析微观孔隙的结构差异; 结合孔喉分形维数划分孔隙类型, 探讨影响储层孔隙发育的主要因素。研究结果表明, 该区储层岩石类型以长石岩屑砂岩为主, 成分成熟度较低, 平均孔隙度为10.8%, 平均渗透率为1.17 mD, 属于低孔低渗型储层。储集空间类型主要为原生粒间孔、溶蚀孔和微裂缝, 孔隙半径平均值为195 μm, 喉道半径平均值为3.5 μm, 储层的孔隙结构类型分为微孔小喉型、小孔小喉型和大孔粗喉型。研究区储层孔喉比总体上较大, 良好的孔喉配置关系是影响储层物性的重要因素, 影响孔隙发育的主控因素则是早期成岩作用、有机酸溶蚀和烃类充注的综合作用。经过相对较弱的压实作用和胶结作用改造后, 原始碎屑为后期溶蚀提供了物质和空间基础, 储层顶部和底部巨厚的富有机质泥岩提供了有机酸溶蚀和烃类充注的物源。