苏里格气田强非均质致密砂岩储层的地质建模

Geological Modeling for Sandstone Reservoirs with Low Permeability and Strong Heterogeneity in Sulige Gasfield

苏里格气田属辫状河沉积,具有特低渗、强非均质性特征,有效砂体呈孤立状分布在致密砂岩中,规模小且连续性、连通性差。气田密井网解剖区的实际建模表明,采用小网格建立井组(或局部)地质模型,有利于有效地表征储层强非均质性的特点;通过辫状河沉积储层的专家研究经验、露头观测和沉积物理模拟实验所形成的地质知识库来确定关键的建模参数,并从多个实现中优选模型储量出现概率最大的作为地质模型的建模思路和方法,可以较好地描述储层的复杂地质特点和强非均质性特征。

Sulige gasfield is formed in a sandy braided river system environment, and its reservoir features in low permeability and significant heterogeneity. Most of its net effective sandbodies, characterized by small size and poor continuousness and connectivity, are dispersively distributed in the tight sandstones and mudstones. Geological model based on trial block with dense well spacing shows that fine grids used in the model is favorable for characterizing the feature of significant heterogeneity. The model parameters are defined by geologic knowledge database of expertise for braided river sedimentary formation, outcrop observation and sedimentary physical simulation. It improves the description of the complicated reservoir characteristic and strong heterogeneity with the method and schedule for gcomodeling by selecting the maximum frequency probability from multi-realizations.