隔夹层成因及其对剩余油分布的影响——以哈得油田东河砂岩油藏为例

RIGIN OF INTERBEDS AND THE INFLUENCE ON DISTRIBUTION OF REMAINING OIL——TAKING COMMAND OF THE HUDSON DONGHE SANDSTONE OILFILED

隔夹层是岩层内部阻挡流体渗透运移的非渗透层和极低渗透层,分为隔层和夹层。隔层是指能阻碍不同层组间流体渗透的非渗透层,而夹层指储层内部能阻碍流体运移的非渗透或者渗透率极低的薄层。考虑到隔层与夹层对剩余油分布的影响具有一定的相似性,因此在本次研究中将统称为隔夹层。储层非均质性是影响水淹规律和剩余油分布最重要的地质因素,当前对储层非均质性研究基本都是围绕砂体展开的,侧重于砂体的内部物性。然而,隔夹层对水淹和剩余油分布的影响程度不亚于砂体本身的非均质性。隔夹层能够将油层分隔成多个连通或者不连通的流动单元,在不同程度上控制着油水的运动,最终对剩余油的分布产生影响。

Interbed is a kind of non-permeable or very low permeability layer which can prevent fluid from seepage and migration in rock strata. It is divided into barrier and interlayer. A barrier is a non-permeable layer that prevents fluid permeation between different formations and interbeds are thin layers of non-permeable or very low permeability in the reservoir. Because the influence of barrier and interlayer on the distribution of remaining oil has some similarities,it will be called Interbed in this study. Reservoir heterogeneity is the most important geological factor affecting the waterflooding rule and remaining oil distribution. Currently,the study of reservoir heterogeneity is mainly centered on sand body,focusing on the internal physical properties. However,the influence of interbed on waterflooding and remaining oil distribution is no less than the heterogeneity of sand body.The existence of interbed can divide the reservoir into several connected or disconnected flow units,which can control oil-water movement and affect the distribution of remaining oil.