Study On Well Pattern Perfection And Comprehensive Adjustment Of Lai 36 Fault Block In Guangli Oilfield

Guangli oil field is a integrated structural reservoir,controlled by 5 third-class major faults.It lies in the east end of central uplift belt,Dongying depression.And there are four main fault blocks from north to south,Lai 27,Lai 38,Lai 36,and Lai 1.The conditions on the ground of Lai 36 fault block are complicated,which is surrounded by some planned areas,such as Jinhu galaxy,logistics park and wetland.Lai 36 fault block is located in the middle of Guangli oilfield,the oil-bearing layer is the fourth member of Shahe-jie Formation.It is 2500m?2730m deep and oil-bearing area is 4.0km2.The current recovery efficiency is 41.8%.Nowadays Lai 36 faces some problems,such as low recovery percentage,low production rate,high injection pressure,shortage of production capacity,etc.These problem seriously influenced the effective production in the oilfields.Based on the deep analysis of the current situation in Lai 36 block,this paper studied the geological characteristics,structural features,reservoir characteristics,physical properties and distribution of remaining oil through the reservoir developing theory and numerical simulation technology.Lai 36 fault block is a low permeability reservoir,which has poor reservoir physical performance,high flow resistance,complicated sedimentary facies changes,bad conjunction and corresponding relationships.Based on the above characteristics,distribution characteristics of reservoir,the properties of remaining oil and the current flood pattern distribution,this paper proposed the well pattern adjustment project to improve the connectivity of effective reservoirs and corresponding injecting-producing relation.When choosing the adjustive well,this paper proposed a new method which can comprehensively consider the effective thickness,oil saturation and corresponding injecting-producing.Reasonable well pattern can be optimized by using this method,which can meet the needs of application and economic index.It can expand the swept area and improve the control degree of water flooding,provide scientific basis for comprehensive adjustment and improving the recovery efficiency of Lai 36.