为探究不同旋回阶段同类微相储集层微观非均质性差异的影响因素及控制机理,运用基准面旋回沉积动力学原理,基于高精度层序地层格架及储集层微观非均质性定量评价参数,分析胜坨油田三区沙二段9砂层组河口坝储集层微观非均质性主控因素。不同级次基准面旋回对河口坝储集层微观非均质性产生差异控制,不同级次基准面升降引起的自旋回与异旋回因素的变化,使可容纳空间与物源供给条件发生改变,导致不同旋回阶段河口坝储集层沉积环境出现差异,使短期旋回中单一河口坝储集层微观非均质性表现为底强顶弱特征,中期旋回中复合河口坝(多期单一河口坝组成)储集层微观非均质性自下向上总体呈变弱趋势,长期基准面旋回中多期复合河口坝间储集层微观非均质性变化规律性不明显。
To identify the factors and mechanisms affecting reservoir micro-heterogeneity in the same type of microfacies at different stages of cycle, the main controlling factors of the reservoir micro-heterogeneity of the mouth bar in Es2-9 Formation of the Shengtuo Oilfield were analyzed based on the sedimentary dynamic analysis of high resolution stratigraphic sequence and quantitative parameters of reservoir micro-heterogeneity. The base level cycles of different stages have a differential control on the reservoir micro-heterogeneity of the mouth bar. The changes of the base level in different orders lead to variation in accommodation space and sediment supply, and in turn changes in sedimentary environments of mouth bar at different stages, as a result, the reservoir micro-heterogeneity of the single mouth bar in short-term base level cycle is strong at bottom and weak at top, the reservoir micro-heterogeneity of compound mouth bar (formed by different stages of single mouth bar) in middle-term base level cycle gets weaker from bottom-up, and the reservoir micro-heterogeneity of compound mouth bar at different stages of long-term base level cycle has no obvious pattern.