采用沉积学、岩石学与石油地质学等方法，在野外露头和钻井岩心观察与实验基础上，对南华北地区周口坳陷二叠系进行致密砂岩储层成岩作用研究，发现太原组胡石砂岩、山西组大占砂岩、下石盒子组砂锅窑砂岩、上石盒子组田家沟砂岩和孙家沟组平顶山砂岩是主要的砂岩储集体。砂岩中石英含量相对较高，颗粒间局部存在较大孔隙，部分颗粒因遭受过构造挤压等作用发生形变或破碎。长石含量相对较低，多为钾长石类。砂岩的填隙物以泥质、硅质、钙质和绿泥石质较为常见。本区岩石遭受的成岩变化主要有压实压溶作用、胶结作用、溶蚀作用及交代作用4种。综合分析本区二叠系砂岩储层的各项指标，认为砂岩普遍处于中成岩阶段B期和晚成岩阶段。%The petrography and diagenesis of the Permian tight sandstone reservoirs in the Zhoukou Depression of the Southern North China Basin were studied using sedimentology, petrology and petroleum geology based on field outcrops, drilling cores observations and laboratory experiments. The main contributive sandstone reservoirs include the Hushi sandstones in the Taiyuan Formation, the Dazhan sandstones in the Shanxi Formation, the Shaguoyao sandstones in the Lower Shihezi Formation, the Tianjiagou sandstones in the Upper Shihezi Formation and the Pingdingshan sandstones in the Sunjiagou Formation. In the sandstones, quartz content is relatively higher. There are larger pores among quartz particles. But many pores disappeared and even the particles were broken because of pressure. Feldspar content is lower and most of which is potash one. The interstitial materials are mainly muddy, siliceous, calcareous and chlorite. Four types of diagenesis can be found, which include compaction-pressolu-tion, cementation, dissolution and metasomatism. Many diagenesis indexes were studied in detail in order to con-firm diagenetic stages, which is in the stage B of the middle diagenesis phase or the late diagenesis phase.
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