河道砂体储层非均质性及其对剩余油分布的影响

储层非均质性对油气田的勘探和开发效果影响较大。结合测井资料及孔隙度、渗透率、二次解释的隔夹层等资料,从平面、层内、层间三个方面,对萨北开发区北三东西块萨尔图油层组SII10~SII16小层的非均质性进行定量研究。结果表明:小层平面上砂体和物性分布的非均质性,使河道侧翼和相互切叠处可能存在剩余油;层内渗透率变异系数、突进系数、级差达到一定数值时,非均质性较强,剩余油可能存在,且层内夹层发育较多的部位剩余油富集;层间非渗透性隔层及非均质系数大,均会导致剩余油大量分布。该研究为萨北开发区北三东西块油层开采提供了借鉴。

Heterogeneity of river channel sand reservoir and its effect on remaining oil distribution

This paper is motivated by studying a greater effect of reservoir heterogeneity on the exploration and development of oil and gas fields. The study is combined with the available data associated with logging, porosity, permeability, and the second interpretation of the interbed and based on the quantitative analysis of heterogeneity of layer SII10 -SII16 in Saertu oil set, in the west part of Beisandong in Sabei development area, from the perspective of plane, inlayer, and interlayer. The study points to the possible occurrence of the remaining oil in channel flanks and the mutual overlap regions due to the heterogeneity in distribution of sand body and physical property occurring in the plane; the presence of stronger heterogeneity and the consequent occurrence of remaining oil, accompanied by the enrichment of the remaining oil in the better-developed parts in interlayers, as is the case when coefficients on variation, onrush, and differential related to interlayer permeability are up to a certain value; and the abundant distribution of much remaining oil produced by impermeable barrier and heterogeneous coefficient between layers. The research may serve as a reference for oil exploitation in the west part of Beisandong in Sabei development area.