Research On Chang4+5 Reservoir Dynamic Analysis And Stability Technique In West Baiyushan

The Chang4+5 reservoir in West Baiyushan is located in Jingan Oilfield,which is typically a reservoir with low porosity and low permeability.Some problems in production are brought owing to further development,making the present development techniques are not suit to the need of development.Therefore stable production technology policy will be researched in order to make a suitable policy for Chang4+5 reservoir to improve the development effect so that the development effect of injection water is all improved based on the above research and the reservoir is developed highly efficiently.Firstly,the geological characteristic were researched in the paper;secondly,the well production status,water cut,pressure distribution,efficiency of oil well,injection-production relationship were analyzed,and some oil wells with high water cut are also studied to find out the reason why the production of some oil wells are very low.And then,reasonable layer pressure,reasonable production rate,reasonably single production and oil production by water flooding were testified.Eventually,the policy of stable oil recovery technology in the reservoir was researched.The research results show that the main factors affecting the productivity are high ratio of high water-cut wells,unsuitable well patter,low use degree of residual oil,low use degree of water-flooding reservoir,uneven distribution of plane stress and high water saturation of reservoir itself.The reservoir engineering demonstration shows the reasonable formation pressure is 12.46MPa and the corresponding reasonable bottom hole flowing pressure is 3.62MPa.At present the average flowing pressure is 3.28MPa and pressure is not appropriate.The reasonable rate of oil production is 0.9%,but the production rate at present is 0.46%which is to lower than that.Reasonable well productivity should be1.9t/d～2.0t/d,but single-well oil production level at present is too low,and the ultimate recovery was predicted at 18.08%.Through the comprehensive analysis of the causes,stable production technology policy were put forward:take the measure of water shutoff and profile control and strengthen the treatment of high water cut;fill holes of potential layer,improve the correspondence between injection and production and use degree of residual oil;strengthen profile adjustment,implement acidification and injection measures to enhance the use degree of water-flooding reservoir;adjust injection parameters by areas,optimize injection-production ratio,improve edge-reservoir energy;Eventually comprehensive treatment plan are put forward combined with other programs.