Reservoir Description And Residual Oil Distribution Study Of Chun 6 Block In Chunhua Oil Filed

Chun 6 block of Chunhua Oilfield located in the south slope of Dongying depression and the west of the fault nose structure,which is in a big nose structure background holding by north and south two boundary fault horst.The main oil-bearing series is Sha-4 member.The average thickness of single sand body is 21 meters,and the average thickness ofoil layer is 15.1 meters.The block oil bearing area is 9.9km²,whose OIIP is 11.2 million tons.The recovery rate will reach 28%.So far,Chun 6 block contains 38 oil wells which is opened about 28 wells and 22water wells is which is opened about 18.The total daily fluid production rate is 427.5tons,daily capacity of 51.3 tons,composite water cut 88%.The daily water-injection rate is 786 m³,the average working fluid level of 880 meters,oil recovery rate 0.21%,25.5%recovery degree,the cumulative oil production of 2.829 million tons,accumulative total of 9.986714 million cubic meters of water injection,accumulated injection-production ratio 1.29,provide total pressure drop of 13.7 MPa.After more than 50 years of water flooding development,serious conflict among layers,each layer using unbalanced condition,oil and water Wells is set to break the serious,well pattern adaptability is poor,imperfect injection-production well pattern of contradictions increasingly obvious.This study takes Chun 6 block for example,on the basis of fine reservoir description^[1],building the geological model of the low permeability thin interbed reservoir,using reservoir engineering and numerical simulation method to understand the remaining oil distribution,which could clear the exploration potential.According to the characters of remaining oil distribution and reservoir heterogeneity,Chun 6 block will adopt hierarchical system development,which contains C1-2 C3-5 and two sets of development series of strata.The recovery degree and the water cut of C1-2 is high,which could Perfect injection-production well spacing to change direction of fluid flow and complement formation energy for improving the oil recovery.According to the reservoir heterogeneity of C3-5.It could use the precise hydrofracture and radial drilling technology to improve water flooding reserves producing level.