碳酸盐岩缝洞型油藏可视化物理模型底水驱替研究

缝洞型碳酸盐岩油藏由于非均质严重,流体流动规律复杂。本文结合油藏实际地层条件,利用天然露头岩心设计并制作出可视化裂缝网络模型和裂缝溶洞模型。考察了不同底水压力梯度下各种模型见水特征。分析了不同模型中剩余油分布特征。实验结果表明:裂缝网络模型无水采油期短,油井见水后,含水率上升很快。与裂缝网络模型相比,裂缝溶洞模型的无水采油期较长。此外,两种模型中的剩余油也存在较大差别。裂缝网络模型中的剩余油以水平裂缝中未波及油为主,而裂缝溶洞模型剩余油则以阁楼油和绕流油为主。

The Study of Bottom Water Flooding in the Development of Carbonate Fractured Cave Reservoir by Visual Physical Simulation

The fluid flowing is complex in the heterogeneous formation of the carbonate fracture- cave reservoir. According to the information of actual of wells and making use of nature exposure core, visual physical simulation models are designed including fracture network models and fracture cave models, which investigates the characteristic of water breakthrough under different bottom pressure gradient in the development. The dynamic distribution of water and oil and the distribution of residual oil in various models are analyzed. The results of experiment demonstrates that in the fracture network models the water free oil production period is short and water cutting is closed to one hundred percent rapidly after water breakthrough. While in the fracture cave models the water free oil production period is longer and fluctuations up to one hundred percent. The residual oil in the horizontal fracture which cannot be swept is dominant in the fracture network model. While the attic oil and flow oil is the main types of the residual oil in the fracture cave models.