曲流河单砂体精细刻画在老油田二次开发中的应用

Application of Fine Description of Single Sand Body in Meandering River to Old Oilfield Redevelopment

点砂坝是曲流河单砂体的基本成因单元,废弃河道和末期河道可以控制点砂坝砂体发育的规模及形态,不同类型废弃河道内部的泥质沉积可以遮挡其两侧点砂坝,使其相互间呈不连通或弱连通状态。曲流河单砂体刻画的核心是对末期(废弃)河道的识别,以及确定河道与点砂坝间的组合配置关系。通过建立废弃河道的测井、地震识别标志,辅以动态监测资料,进行了地下曲流河单砂体精细刻画,可为认识油藏提供精确的地质模型,从而有助于解决注采矛盾,并形成对剩余油富集规律的新认识。

Point bar is the basic genetic unit of meandering river sand body,which can be controlled by abandoned channel and final channel in scale and configuration.The inner muddy deposit in different types of abandoned channels may keep out their two-side point bars so that creates the disconnecting or weak-disconnecting status between them.The key of single sand body description is to identify the final or abandoned channel and make the assemblage relation clearly between the channel and the point bar.By the establishment of logging and seismic signs for the final channel,integrated with the dynamic monitoring data,this paper presents the fine description of the sand body,which can provide detailed geologic model for reservoir recognition and help to deal with injection-production contradiction,hence obtaining new knowledge of the remaining oil accumulation in it.