苏北盆地复杂断块油藏多夹层模式划分及控油规律

复杂断块油藏含油层系薄,隔夹层发育复杂,因此多夹层控制下的剩余油分布规律对其水驱技术政策的制定意义重大。首先基于典型模型研究了夹层数目(贯通注采井)、夹层发育规模及夹层展布位置对于水驱后储层纵向波及效率及剩余油分布模式的影响。然后依据复杂断块油藏储层特征建立了16种表征注采井间不同夹层数量及展布位置的多夹层驱替模型,并将其归纳为"多驱少"和"少驱多"两种驱替模式。总结了两种驱替模式下夹层对于剩余油分布的控制作用及其差异性。基于多夹层驱替模式划分方法及控油规律,针对典型区块提出补层及新井部署等挖潜对策,取得良好应用效果。研究成果及应用实践可为其他多夹层油藏中高含水期的剩余油挖潜提供借鉴意义。

Classification of Multi-interlayers Pattern and Effects on Residual Oil Distribution in Complex Fault-block Reservoir

Complex fault-block reservoirs have thin oil-bearing series and complex development of isolated interlayers. Therefore, the distribution of residual oil under the control of multiple interlayers is of great significance to the decision of potential exploitation measures for water-driven complex fault-block reservoirs. Based on the typical model, the influences of the number of interlayers (across injection and production wells), the size of interlayer development and the location of interlayer distribution on the vertical sweep efficiency and residual oil distribution of reservoir after water flooding were studied. Then, according to the reservoir characteristics of complex fault block reservoirs, 16 kinds of multi-interlayer displacement models simulating the number and distribution of different interlayers between injection and production wells were established, and they were classified into two displacement modes: "less to more more to less classification method of multi-interlayer displacement mode and the law of oil control, this paper puts forward some potential exploration countermeasures such as perforation adding and new well deployment for typical blocks, and obtains good recovery performance. The conclusions and its success application can provide reference for other multi-layered reservoirs in high water-cut period of residual oil exploration.