Affect Evaluation Of Development Of Chang 2 Reservoir In West Of Liuluo Valley

Chang 2 reservoir in Lujiapan,west of Liuluoyu,Xiasiwan Oilfield,is an important block of Yanchang Oilfield Co.,Ltd.,with an area of 73.22km2 and an estimated oil-bearing area of58km2,with a total number of 483 Wells.At present,the reservoir microstructural characteristics are not clear,the reservoir distribution characteristics are not clear,and the direction of subsequent potential exploration measures is not clear.With Liu Luo valley temple bay oilfield blocks long 2 fine stratigraphic classification and correlation,sedimentary microfacies and sand body distribution characteristics of research,make clear Liu Luo valley area of micro structure characteristics,reservoir characteristics,the production dynamic analysis on the basis of the research on reservoir development effect evaluation,reservoir waterflood technology policy,well deployment in the study area is put forward.The results show that the formation of Chang 2 Formation in the western Liuluoyu area is a delta front subfacies,and the reservoir sand body is dominated by underwater distributary channel microfacies.It is a structure-lithologic reservoir with low porosity and low permeability.Productivity of oil Wells that rely on formation natural energy in the study area decreases rapidly,daily oil production is low,and the proportion of low-producing Wells is large.At present,the injection and production well pattern in the study area is not perfect enough,the utilization degree of water flooding reserves decreases,and the water flooding efficiency decreases.The study determined that the reasonable flow pressure of Chang 2reservoir is 0.9MPa,the reasonable production pressure difference is between 5.4-7MPa,the maximum injection pressure of injection well head is 8MPa,the reasonable injection-production ratio is about 1.1,the reasonable oil recovery rate is about 0.7%,and the average single well productivity is about 0.9t/d.The diamond-shaped inverse nine-point well pattern was adopted in the study area.Considering the fracture distribution law in the study area,the injection and production well pattern in the west of Liuluoyu with a well distance of225 meters was deployed as a whole in accordance with the optimal plan.The practical and feasible water flooding development technology policy formulated in this paper has certain reference significance for efficient water flooding development of similar reservoirs in Ordos Basin.