渤海海域A油田夹层控制下的剩余油分布模式

Remaining oil distribution pattern controlled by interlayer in A oilfield in Bohai Sea

为分析并总结夹层控制下的剩余油分布规律,以高含水开发阶段的渤海海域A油田为研究对象,开展了储层夹层构型精细解剖和数值模拟研究。结果表明:渤海A油田夹层以泥质夹层和物性夹层为主,平均厚度小于1 m,表现为顺物源的"前积式"和垂直物源的"上拱式"展布样式。内部夹层的延伸规模、发育位置控制着剩余油的分布位置和富集程度。夹层水平延伸距离越远,夹层底部区域剩余油的富集范围越大;在注采井与夹层配置方面,采油井钻遇夹层的情况下,夹层对剩余油分布影响更大,夹层底部剩余油更为富集;在夹层和储层韵律性控制下,层内剩余油分布模式分为夹层顶部富集型、夹层上下富集型和夹层底部富集型3种。该成果对油田后期调整挖潜和实施稳油控水措施均提供了决策依据。

In order to analyze distribution rule of remaining oil controlled by interlayer,the reservoir architecture and numerical simulation analysis of interlayer were carried out in Bohai A oilfield with high water cut stage.The results show that foreset imbricate interlayers are mainly composed of shale interlayer and tight sandstone interlayer,which average thickness is less than one meter.The remaining oil is controlled by position and area of interlayer.The longer the horizontal extension length of interlayer is,the greater the enrichment area of remaining oil is in the bottom zone of interlayer.In the injection well,oil well and interlayer configuration,when the production well penetrated into interlayer,interlayer has greater effect on remaining oil,which will be more enriched in bottom zone of the interlayer.Under the control of interlayer and reservoir rhythmicity,the remaining oil distribution patterns were divided into three types:interlayer top enrichment type,interlayer top-bottom enrichment type and interlayer bottom enrichment type.The results provide decision basis for adjustment,tapping potential and stabilizing oil and controlling water measures in late stage of oilfield.