The interlayer and internal heterogeneities of the delta sandstone reservoir in 7 th and 8 th groups of Es2 formation at the second district of Shengtuo oilfield have weakened in high water-cut development period (synthetical water-cut exceeds 90 %), but plane heterogeneity increased. However, reservoir heterogeneities in different microfacies and positions are different. Most of the reservoirs have lower heterogeneous synthetic index, which shows more serious heterogeneity. From serious to weak, the mirofacies are in turn distributary interchannel,levee, far bar distributary river course and debouch bar. In debouch bar, heterogeneity in bar side is the most serious, and that in bar host is more serious, and that in bar top is middle. More serious reservoir heterogeneity has more influence on injecting development, which leads to more differences of remaining oil distribution.%胜坨油田二区沙二段7,8砂组三角洲砂岩油藏高含水期(综合含水率大于90%)的储层层内、层间非均质性有所减弱,但是其平面非均质性增强,且不同微相不同部位的储层非均质性有较大差异。但是,大都具较小的非均质综合指数,呈现出较强的非均质性。按照非均质性的强弱,这些微相依次为分流间湾、天然堤、远砂坝、水下分流河道和河口砂坝。其中在河口砂坝内,侧缘储层的非均质性最强,坝主体次之,坝顶部则呈中等非均质性。较强的储层非均质性对注水开发影响较大,因而造成剩余油分布的较大差异。
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