变差函数在储层评价及开发中的应用:以杨家坝油田为例

Application of Variogram in Reservoir Evaluation and Development:Taking Yangjiaba Oilfield for Example

目前江苏省杨家坝油田已进入高含水阶段且非均质性严重。为了满足油田开发后期的需要,并进一步改善油田开发效果,达到提高原油采收率的目的,需要精细描述单砂体储层的平面非均质性,研究平面非均质性对油田开发效果的影响。利用杨家坝油田的渗透率数据计算了不同层(重点按照沉积微相类型)变差函数的变程。通过变程反映变量的影响范围,对不同层的非均质性进行了精细描述,并分析了变程的影响因素。根据变程的不同,指导注采井井位部署。该方法的研究不仅增加了三角洲—湖泊沉积体系储层平面非均质性研究的深度和精度,而且为精细描述高含水后期的剩余油分布规律提供了一定的理论依据。

Yangjiaba Oilfield exploration has entered the high water stage with serious heterogeneity. To meet the needs of the later development and further improvement of its development effect so as to enhance oil recovery, it is necessary to describe in detail the plane heterogeneity of the single sand reservoir layer and research the effect of the plane heterogeneity. In this paper, Yangjiaba Oilfield is taken as an example for the calculation of the range of variogram in different layers （mostly according to the sedimentary microfacies） with the practical permeability data. The heterogeneity of different layers is characterized accurately by the range influence on the variables and the factors are analyzed at the same time. Then the deployment of injection and production wells is directed based on the differences of the range. This method not only increases the research depth and precision of the reservoir heterogeneity of delta and lake deposition system, but also provides a theoretical basis for the fine description of the distribution of residual oil in the late period of high water.