Yanchang Oilfield Development Adjustment Scheme Donghan Oil Region

When the oil deposit has been exploited for a period of time, the moisture content willincreased, the oil production will decrease, the contradictions between he planes, theinter-layers and the inner-layers will increase, water injection effect gradually becomes poor,input and output efficiency decline. These are the inevitable stage, to the middle and laterperiods of the reservoir development, therefore, must take the necessary for reservoirdevelopment adjustment measures, toslowthe water cut rising rate, slow down productiondecline. Donghan oildom have been exploited for more than ten years. The study area is at ahigh water cut stage, for low Wells, low utilization rate of water injection, in order to solve themain problems existing in the exploiting process in the area. An adjustment scheme forexploiting Donghan oildom must be carried out as soon as possible.The study on the theory of petroleum geology of development as the guidance, theapplication of petrel geological modeling software, reservoir modeling technique usingdeterministic modeling and stochastic modeling combined, the reservoir structure model andattribute model are established. From the ways of development, adaptability of well network,the characteristics of the development of other aspects of the comprehensive study of reservoirengineering, analysis of the present situation of exploitation, thus more effectively solves theinjection production well network does not improve the single well production leads to low,water cut rising quickly and other outstanding problems due to mining. The numericalsimulation software of formation pressure, the cumulative oil production, cumulativeproduction water, comprehensive water cut development indicators were fitted using eclipse.Quantitative analysis of residual oil in the horizontal and vertical distribution of reservoirremaining oil enrichment zone is put forward, and the main control factors of remaining oildistribution, according to the distribution of enrichment area and main controlling factors, hasdeveloped4injection production system adjustment scheme, and index prediction ofdevelopment plan, through the development of effect analysis, optimized development thereasonable scheme, at the same time, the comprehensive evaluation of reasonable well spacingdensity and potential, put forward the development scheme of the comprehensive adjustment of new and old wells, Dingbian oilfield as the Eastern Han oilfield to improve ultimaterecovery and provide scientific basis for.This paper mainly following results and understanding are obtained:(1) the current EastHan oil at a low degree of recovery, high water cut development stage, stable yield. But withthe reasonable injection production well network compared with the present well pattern,situation of oil sand body adaptability, local area well pattern is not perfect, control degree ofwater flooding in low, fracture, extension area reservoir grade difference of oil-waterrelationship is not clear, problems still outstanding, increase reserves control degree of waterflooding potential is still huge.(2) based on previous understanding, research that the East HanChang Chang2oil-bearing formation oil belongs to the river HiraharaAso deposition, the sandbody is mainly the delta plain distributary channel sand bodies, mainly in the north and southto the main; Yan9, extension10layer is the river swamp sedimentary environment,development of meandering river river, river from south to North trending, slightly northeastward development trend.(3) of injection production system that, Dong Han oil reserves ofabout1/4unused,1/3low producing degree of reserves. Current water rate is about65%, thecalculation of rational oil-water well ratio1.95:1, now well network actual oil-water wellnumber ratio of4.17:1, the difference is greater than0.5, oil and water well ratio is too large.(4) in layer heterogeneity Yan9,10reservoir mainly is medium to weak inhomogeneous type,Chang2reservoir group mainly showed strong a moderately heterogeneous type, the minorityhas a weak heterogeneous type. The interlayer heterogeneity is strong, the Yanan group andthe reservoir plane heterogeneity is medium to weak, local non mean strong.(5) should nowincrease the single well production to stabilize and improve the recovery rate, tamp, oilfieldstable production base for target. Based on the existing well pattern, to strengthen the waterinjection well adjusted as the key of the well network to improve the work; oil productionstable implementation countermeasures to fine injection production adjustment orientedcontinue, increase the dynamic monitoring and data application, guidance to furtheradjustment of injection production.(6) the remaining oil research shows, Dong Han oilfieldYan91, long1, long21-1, long21-2remaining oil enrichment degree is high, these layers ofresidual oil reserves abundance movable high value areas mainly in the four well region1119well area,1518-2-1528well area,1819-1141-1177well area,1537-1-1540well area, hascarried on the analysis to the remaining oil forming factors.(7) showed that the injectionproduction parameter optimization, reasonable injection production ratio should be in2above,the rational distribution of liquid production should not exceed12m3/d, the high water cutstage may be appropriate to increase the underflow; oil well pressure is in the range of4MPa,the water injection pressure is not more than10.14MPa. Recovery prediction of comprehensive results for20.18%.(8) simulation results based on the comprehensivegeological study, numerical, developed a comprehensive adjustment plan, comprehensiveadjustment scheme can achieve better development effect.