Abstract: The exploration and development of reservoir in deep zone is the anly way for further development of the old ailfields in eastern China. The paper systematically analyses oil-gas prospects in Es₃-Es₄ of Gegangji northern sag,Dongpu Depression and the types of sand body,as well as diagenesis and its effect to reservoir. Recent exploration outcome demonstrates that there are large-scaled sandbodies from different directions of the gravity flow channel and mid fan channel in deep zcane of Gegangji northern sag. Due to strong diagenesis, the secondary porosity zones are developed, which has improved reservair features and has made it possible to forni large-scaled subtle reservoir in the depression. The study will be helpful for future exploration in the area.

Key words: Gegangji northern sag, deep zone, secondary porosity, influence factor, low porosity and low permeability, reservoir type, reservoir condition

摘要： 对东淮凹陷葛岗集北洼深层Es₃-Es₄^上亚段的油气资源潜力、储层砂体类型、成岩作用及其对储层性质的影响作了较系统地论述,结合近年来的勘探成果进行综合分析论证,认为葛岗集北洼深层有来自不同方向的较大规模的扇中水道砂体和重力流沟道砂体存在,由于成岩作用强烈,其内次生孔隙成带发育,改善了储层的性能,使洼陷中有形成较大规模隐蔽油气藏的可能.对其后的勘探有一定的参考作用.

关键词: 葛岗集北洼, 深部地层, 次生孔隙, 影响因素, 低孔低渗, 储层类型, 成藏条件