The Study On Stable Production Technology Of Chang 4+5 Reservoir Of Triassic Yanchang Formation In Eastern Jiyuan Oilfield

At present,the comprehensive water cut of Chang 4+5 reservoir in eastern Jiyuan oilfield is 54.7%,the recovery rate is 0.84%,and the recovery percent of reserves is 6.4%.In the past two years,the reservoir pressure has been gradually raised,the Water flooding condition has improved,the two decreasing have declined,and the stable production situation on the overall reservoir has improved.However,the contradictions affecting the long-term stable production of reservoirs are still prominent.The main contradictions are as follows: contradictions between and within reservoirs are prominent;reservoir fracture flooded seriously;the overall pressure of the reservoir remains high,but its distribution is not uniform;the proportion of low yield wells is high,and it is difficult to control them comprehensively.At present,the average output of single well in this area is only 1.08t/d.Among them,253 low-yield wells with output less than 0.5 tons and account for 30.0% of the total number of oil wells opened,and the proportion of low-yield wells is high,so it is difficult to control them comprehensively.There are two main types of low-yield wells in reservoirs: one is caused by formation reasons;the other is caused by uneven distribution of local pressure,and long-term inefficient water injection or flooded.In view of the above reservoir development contradictions and in order to realize the long-term stable production of reservoirs,it is necessary to carry out research on the technology policy of stable production of oil reservoirs,recognize the essential contradictions that restrict the stable production of oil reservoirs,and constantly optimize the technology policy of stable production,so as to provide theoretical basis and technical support for further improving the development effect and recovery factor and ensuring the stable production of oil fields.The reservoir potential can be fully exploited through fine characterization of single sand body;The study on development dynamics affecting long-term stable production of reservoirs;The fracture distribution law and well pattern optimization research of the reservoir;The fine water injection research of the reservoir;The remaining oil research and production test;The study of improving single well productivity technology,and the detailed dissection of the stable production situation of the reservoir.Evaluating the current technology policy for stabilizing production,recognizing the essential contradictions that restrict the stable production of reservoirs,focusing on the study of basic laws,aiming at improving single well productivity and ultimate recovery,activelycarrying out technological innovation,gradually forming matching development technologies adapted to the actual distribution of fractures and well pattern optimization,fine reservoir water injection,remaining oil research and production,and improving single well productivity,etc.Achieving the goal of long-term stable production and development of Chang 4+5reservoir in eastern Jiyuan Oilfield.