海上复杂碎屑岩储层油气藏地质建模关键技术

Key techniques for geological modeling of offshore complex clastic rock reservoirs

渤海海域油气田以陆相复杂碎屑岩沉积为主,开发井距大,资料有限,随着各主力油田进入中高含水期,储层建模面临较大挑战。提出了海上复杂碎屑岩储层油气藏地质建模关键技术:(1)基于模型的地质风险定量评价技术。通过模型不确定性分析(建模参数选取)、实验设计及模型实现、储量和可驱替体积概率分布统计及模型排队优选等工作,对油田开发地质风险进行定量评价。(2)基于沉积演化的中深层储层表征技术。建立沉积演化模型,通过网格等比例剖分、井点数据标定,将沉积演化模型转换为三维地质建模约束趋势体,进而建立储层岩相及属性模型。(3)基于数模动态响应的构型界面表征技术。通过小尺度构型界面定量表征,基于数模动态响应确定构型界面对渗流的影响。渤海8个油田应用表明,本文提出的复杂碎屑岩储层建模关键技术不仅在油气藏开发方案编制实施中成效显著,还在综合调整中成功指导了236口调整井的部署,3年累计见效增油467.7×104 m3,可为同类型油气藏的高效开发提供借鉴。

Oil and gas fields in the area of the Bohai sea are mainly deposited with terrestrial complex clastic rock,where the development well spacing is huge and limited data is got,and of which main oil fields enters middle-high water cut stages,all these challenging reservoir modeling greatly.Key technologies for geological modeling of overseas complex clastic reservoirs are put forward：1）quantitative evaluation technology for geological risks based on models：the oilfield development geological risks should be quantitatively evaluated through a series of work like the uncertainty analysis with models（selection of parameters for modeling）,experiment design and model implementation,probability distribution statistics of reserves and volume displacement,and queuing and optimizing of models.2）middle-deep reservoirs characterization based on depositional evolution：a depositional evolution model should be established and transformed into 3 D geological modeling constraint trend for lithofacies and properties modeling by virtue of equal proportion grid division and well data calibration.3）configuration interface characterization based on dynamic responses of numerical simulation：the effects of the configuration interface on percolation should be determined through small scale quantitative characterization of configuration interfaces and on the basis of dynamic responses from numerical simulation.The application in eight oil fields in the Bohai sea suggests that the key modeling technologies for complex clastic reservoirs not only brought about prominent achievements in the practices of the oil and gas reservoirs development plan,but also successfully guided the deployment of 236 adjustment wells during the comprehensive adjustment,which effectively increased oil production as a whole of 467.7×104 m3 in three successive years,and hence,can provide reference for the effective development of oil and gas reservoirs of the same type.