Research on Differences of Controlling of Fault to Oil Accumulation in and outside Oil Source Area——An Example of Fuyu—Yangdachengzi Oil Layers in Sanzhao Depression and Chang-10 Block,Songliao Basin

On the basis of the research on fault development and distribution in the Sanzhao depression and Chang-10 block,Songliao Basin,the differences of controlling of fault to oil accumulation in the Sanzhao depression and Chang-10 block was studied by use of the spatial distribution of the faults in the Sanzhao depression. It was considered that there mainly developed T2 faults of the Fuyu—Yangdachengzi oil layers in SN direction in the Sanzhao depression and Chang-10 block,which were high density,uneven distribution in the plane,small fault throw and short extended distance. On the section,resembling flower-like graben-horst combinations were formed by the control of basement faults. In a plane the faults are dense to be in belt. Oil from K1qn1 source rocks migrated vertically through T2 source faults in the Sanzhao depression and downward into the Fuyu—Yangdachengzi oil layers. Oil from the Fuyu—Yangdachengzi oil layers of the Sanzhao depression was transported laterally into the Fuyu—Yangdachengzi oil layers though T2 faults in the Chang-10 block. T2 fault-condensed belt in the Sanzhao Depression is not the major accumulation position of oil in Fuyu—Yangdachengzi oil layers. Oil is mainly accumulated in the bottom walls of T2source faults. T2 fault-condensed belt in the Chang-10 block is the main accumulation position of oil in the Fuyu—Yangdachengzi oil layers.