不同开发时期砂岩油藏储层非均质三维模型特征

以济阳坳陷东营凹陷胜坨油田二区为例,简述非均质综合指数的计算、作用和意义。按储层随机建模的思路和方法建立非均质综合指数三维模型,主要包括储层数据准备、构造模型、非均质综合指数分析、非均质建模和显示5个环节,直观表征储层的空间非均质性特征。分析了东营组三段开发初期、中期和后期的非均质综合指数变差函数和三维模型特征,得出了不同开发时期储层非均质性的变化规律。结果表明,随注水开发的进行,变程(a)减小,基台值(c₀+ c)增大,块金效应值(c₀)为0。开发初期储层以中等非均质性为主,中期以较强-中等为主,后期以较强为主。纵向上,上部的非均质综合指数差异较大,下部的差异相对较小。纵向上的层间和层内非均质性要强于平面非均质性。注水开发加剧了储层的非均质程度。

Characteristics of heterogeneous 3-D model of sandstone reservoirs in different development stages

The calculation of heterogeneous aggregative index,together with its function and significance,is briefed based on the data acquired from the Block Ⅱof Shengtuo oilfield.The 3-D modeling of heterogeneous aggregative index by employing the reservoir stochastic method includes the following five stages:preparation of reservoir data,construction of model,analysis of heterogeneous aggregative index,construction of heterogeneous model,and display of modeling results.The spatial heterogeneity of reservoir is vividly characterized by the model.An analyze of the variation function and 3-D model characteristics of heterogeneous aggregative index of sandstone in the Third Member of Dongying Formation in its earlier,middle,and later stages of development reveals the changing pattern of reservoir heterogeneity at different development phases.According to the results, the range of influence(a)decreases with waterflooding,while the sill value(