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煤系地层的砂岩中所含水介质呈酸性，致使其砂岩储层具有碳酸盐胶结物含量低、硅质胶结物含量高、粘土矿物中富含高岭石的显著特点。由于各种成岩作用，特别是压实作用和硅质胶结作用的影响，使得华北石炭－二叠系煤系地层的砂岩储层属于低孔低渗型，其孔隙类型主要为次生孔隙。表生成岩作用是形成良好储层的主要作用。华北石炭－二叠系构造演化史的研究表明，在印支期及燕山晚期该区有两次抬升，使砂岩遭受风化和淋滤，长石等矿物溶解形成大量次生孔隙，储集性得到改善。其有利孔隙带的分布与不整合面有密切关系，孔隙率随着远离侵蚀面而变小。
The water medium in the coal measures of the coal measures is acidic. As a result, the sandstone reservoirs have the characteristics of low carbonate cement content, high siliceous cement content and high kaolinite content in clay minerals. Due to various diagenesis, especially compaction and siliceous cementation, the sandstone reservoirs in the coal measures of the Carboniferous-Permian coal measures in North China belong to the low porosity and permeability type, and the pore types are mainly secondary pores. Table igneous rock formation is the main function of forming a good reservoir. The study on the tectonic evolution of the Carboniferous-Permian in North China shows that there were two uplifts in the Indosinian and late Yanshanian terrains, causing weathering and leaching of sandstones, dissolution of feldspar and other minerals to form a large number of secondary pores, improve. The distribution of its favorable pore zone is closely related to the unconformity, and the porosity decreases with distance from the erosion surface.