The Differences Of Reservoir Quality Of The Ek22 Oil Group In Wangguantun Oilfield

Wangguantun oilfield has a complicated fractured structure.The reservoir of the Ek2 formation is widely distributed.There are differences of the reservoir quality in different fault blocks and the reservoir quality in Ek22 oil group is also different.The main controlling factors are not clear.At the same time,in the middle and late stages of development,the preponderance flow path has formed in some reservoirs,but it is not clear about its distribution and genetic mechanism.Taking the Ek22 oil group of Wangguantun oilfield as the research target,the reservoir characteristics and the preponderance flow path are investigated by application of core,logging,casting thin slice,mercury pressure and other data.The distribution of sand body and reservoir quality of the Ek22 oil group are detailed,the main controlling factors are revealed,the distribution of the preponderance flow path and the genetic mechanism are analyzed,which provide geological basis for the further development and production of the oilfield.The facies of Ek22 in Wangguantun oilfield is nearshore subaqueous fan.The distribution of sand body is affected by the source and hydrodynamic condition.Sand body of the Guan 984 fault block located near the source is overlaid by multiple-stage channels.Thick sand body of the Guan 68 and the Guan 998 fault block far from the source is stable.The sand body in main channel microfacies is thick,stably distributed and continuous,followed by the sand body in sub channel.The reservoir of the Ek22 oil group is mainly composed of middle to low porosity and medium to low permeability feldspar sandstone and debris-feldspar sandstone.The reservoir space is mainly primary pore,and secondary pore is mainly intergranular dissolution pore.The reservoir has strong heterogeneity.Reservoir quality is mainly affected by sedimentary facies and cementation.The preponderance flow path caused by sedimentary facies and low cemented degree is distributed from East to West and mainly in the bottom of main channel sand body.