渤海特高含水期油田剩余油分布规律及挖潜策略

油田进入特高含水期后,受储层韵律性、平面非均质性、断层边界及纵向夹层等影响,油层水淹规律及剩余油分布十分复杂。为进一步提高油田采收率,结合新钻井水淹层测井解释成果、密闭取心、生产动态及油藏数值模拟等资料,对渤海Q油田水淹特征和剩余油分布规律进行深入研究,并提出相应的调整井挖潜策略。认为油层底部、井点附近及边水油藏注采主流线水淹严重,油层中上部、井间区域、遮挡带附近和底水油藏边部水淹较弱或未水淹,纵向上井间区域水淹层占比为8%～65%,平面上生产井有效动用半径为70～150 m。提出利用水平井进行井间加密、边部完善井网、垂向穿夹层动用屋檐油及井网调整等挖潜策略。结果表明:利用水平井挖潜特高含水期剩余油,可有效改善开发效果,提高油田采收率,并为海上类似油田的调整挖潜提供借鉴。

Distribution Law and Potential Exploitation Strategy of Remaining Oil in Bohai Sea High Water-cut Stage

After the oilfield enters the extra high water-cut period,it is affected by the rhythm of the reservoir,the planar heterogeneity,the fault boundary and the longitudinal interlayer.The flooding law of the oil layer and the remaining oil distribution are very complicated.In order to further improve oil recovery,combined with the results of logging interpretation of new drilling water-flooded layers, closed coring,production dynamics and numerical simulation of reservoirs,the flooding characteristics and remaining oil distribution of Bohai Q oilfield were studied in depth.And put forward the corresponding adjustment well tapping strategy. It is considered that the bottom of the oil layer,near the well point and the main line of the side water reservoir are heavily flooded,and the upper part of the oil layer, the interwell area,the vicinity of the shielding zone and the edge of the bottom water reservoir are weak or not flooded,and the vertical well is inter-well.The proportion of regional water-flooded layers is between 8% and 65%,and the effective utilization radius of production wells on the plane is between 70~150m. It is proposed to use horizontal wells for inter-well encryption,edge improvement of well network,vertical penetration of roofing roofing oil and well pattern adjustment.The results show that the use of horizontal wells to tap the extra high water-bearing period residual oil can effectively improve the development effect.Improve oil recovery and provide reference for the adjustment and digging potential of similar offshore oil fields.