南马庄油田沙三段储层特征

南马庄油田的产层为下第三系沙三段，储集砂体为浪控三角洲和湖滨滩坝相．储集岩性以细粒长石砂岩和粗粉砂岩为主．主要自生矿物为碳酸盐和高岭石、伊利石、伊－蒙混层、绿泥石等粘土矿物．还有少量自生石英和长石矿物．储集孔隙以次生粒间孔隙为主，其形成机制与有机质的热演化有关．储层物性虽好，但存在明显的层内、层间和平面非均质性．油层分布受岩性和构造的双重控制．

Reservoir Characteristics of the Third Member of Shahejie Formation in Nanmazhuang Oil Field

he production layers of Nanmazhuang Oil Field is in the third member of Shahejie formation. The depositional sequence,lithologic data and sandstone distribution patterns indicate that the sandstone was deposited by wave-dominated deltas and lakeside beaches and bars. The main authigenic minerals include carbonate kaoninite,illite,miscible layer of illite-montmorillonite and chlorite. Most of the porosity is secondaryintergranular space. The reservoir quality is generally good,but obvious heterogeneities exisit in and betweenthe layers and on the surface. Hydrocarbon distribution is controlled by lithology and geologic structure.