油藏数值模拟技术在大庆高含水油田的应用

Application of Reservoir Numerical Simulation Technology at the High-water-cut Stage of Daqing Oilfield

经过多年的稳产高产,大庆油田进入高含水阶段,由于油层多,层系之间的差异大,井网划分跨层系现象较为普遍,剩余油分布越来越复杂,给油田稳产和调整挖潜带来的难度越来越大,剩余油分布预测成为高含水期油田的开发关键。为定量分析大庆油田进入高含水期的剩余油分布特征,以精细油藏描述为基础,结合油藏开发动态,利用油藏数值模拟技术再现油藏生产过程和不同时期油水分布。基于大庆油田北三区西部开发数据和监测资料,利用地质模型对区块生产过程进行了模拟,再现了油藏开发历程。由于层段多、砂体形态复杂、层内非均质性较严重,油层部分部位控制程度相对较差,在油层的边角部位、差油层及层内差储层段成为剩余油分布的集中区。以该剩余油的分布特征提供相应的措施调整,从而解决油藏注水开发中的3大矛盾,对油田开发生产起到了很好的指导作用。

After years of high and stable yield,Daqing Oilfield has entered the high water-cut stage,because of more oil layers,the large differences between the layers,well pattern division across the layers is more general,the distribution of remaining oil is more complex,it is more and more difficult for tapping the potential of oil and adjustment,the remaining oil distribution forecast becomes the key oilfield development at in high water cut stage.To quantitatively analyze the distribution of remaining oil of Daqing Oilfield at high water cut stage,a technical idea that can reappear the production process of reservoir and the oil-water distribution has been presented for reservoir numerical simulation technique. And the idea is based on fine reservoir description and combines with the dynamics of reservoir development.On the basis of the development and performance data in the demonstrating area,the production process is simulated with geological model.It shows that the sand bodies are featured by more sequences,complex formtion,serious interlayer heterogeneity and relatively poor control of oil layer.So,it is probable that remaining oil is concentrated in corners of oil layers,poor reservoirs and poor intervals in layer.Based on distribution characteristics of remaining oil,corresponding adjustment measures are applied.And the three contradictions in the process of water flooding are also solved,which provides guidance for the oilfield development.