渤海SZ油田剩余油控制因素及挖潜策略研究

Study on the Control Factors and Potential-tapping Strategies for the Remaining Oil of SZ Oilfield in the Bohai Sea

渤海SZ油田经首次加密调整后开发效果大幅提高,但随着油田逐渐进入高含水阶段,剩余油分布日趋复杂,进一步调整和挖潜的难度增大,需要探索新的技术手段和开发策略以实现油田的可持续开发。针对此现状,在三角洲相储层构型理论的指导下,综合利用岩芯、地震、测井等资料,详细刻画了单一成因砂体在垂向及平面的接触关系,并在此基础上分析了储层构型对油水运动的控制作用。结果表明,油田进入高含水期后,层间相带干扰、层内夹层及平面构型单元接触关系是控制剩余油分布的主要因素。为了进一步提高油田开发效果,提出了基于构型单元的层间水平井挖潜策略、基于构型单元的层内水平井挖潜策略、基于构型单元的平面小井距加密策略等,构建了一套海上三角洲相油田综合调整后的剩余油挖潜技术方法,并取得了良好的应用效果。

The recovery efficiency of SZ Oilfield in the Bohai Sea has greatly improved since the first infilling adjustment.However,with the oilfield transitioning to the high-water-content stage,the distribution of the remaining oil has become increasingly complicated and it has become more difficult to make further adjustments and realize the untapped potential;sustainable development of the oilfield necessitates new technical means and exploitation strategies.To cope with these challenges,a detailed description of the vertical and in-plane contact relationship of homogeneous sand bodies was carried out on the basis of the delta facies reservoir architecture theory,by comprehensively utilizing coring,seismic,and logging data.With this approach,the role of reservoir architecture in controlling the movement of oil and water was analyzed.The results showed that during the high-water-content stage,inter-stratum and inter-zone interference,intercalated beds,and joints between plane-architecture units were critical to controlling the remaining oil.To further improve the oil field development efficiency,three architecture unit-based strategies are proposed for tapping the potential of inter-stratum and intra-stratum horizontal wells and infilling densely spaced horizontal wells.A set of technologies was developed for tapping the potential of the delta facies oil reserves remaining after a comprehensive adjustment is made to the oilfield.The strategies and technologies were then applied,achieving good results.