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

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