曲流点坝内部剩余油形成与分布规律物理模拟

建立了曲流点坝物理模型,模拟地下曲流点坝储层进行驱替实验。观察注入剂的运动规律,同时,在模型上布置了测量电极,以双电极法测量驱替过程中垂向电阻变化,反映注入剂波及高度的变化规律。分析了侧积泥岩夹层的建筑结构对注入剂在点坝砂体中的流动规律,以及对剩余油的形成分布的影响。通过实验研究证实,在曲流点坝内部,侧积泥岩夹层对注入剂具有强烈的遮挡作用,受其影响形成侧积体差异型剩余油、重力型剩余油以及压力异常型剩余油三种类型剩余油,主要分布在点坝的中上部。在实际生产中,利用水平井钻遇点坝上部进行开采是主要的手段。

The formation and distribution of residual oil in meander point bar by physical modeling

We have established a physical model for the meander point bar. A displacement experiment has been cartied out by modeling the reservoir layers of meander point bar, and the rule of the movement of injectant has been observed. Measuring electrodes were arranged on the model, and the vertical resistance changes in the course of displacement process were measured by pair-electrodes method. The measurement reflected the rule of change of injectant sweeping height. We have investigated the affection of a laterally accreted mudstone-interbeding architecture on the flow of the injectant in the sandbody of the point bar and on the formation and distribution of the residual oil From this experimental study, we have proved that in the meander point bar, the laterally accreted mudstone interbeds have a very strong shielding effect on the injectant. Under its affection, three kinds of residual oil are formed., gravity mode residual oil, laterally accreted body anomaly mode residual oil, and pressure anomaly mode residual oil. They are mainly distributed in the middle and upper parts of the point bar. In production, producing the upper point bar residual oil by horizontal drilling should be the major measure.