储集层构型分级套合模拟方法

Hierarchical nested simulation approach in reservoir architecture modeling

由"层次约束、模式拟合与多维印证"的构型研究思路出发,在分析储集层构型空间分布特征及构型要素建模难点基础上,提出分级套合进行储集层构型模拟的思路和方法,即不同级次的构型应采用不同的建模方法,并将每一级次模拟的结果作为下一级次建模的信息和约束条件。以曲流河砂体构型解剖为例,对复合曲流带级次的模拟,改进了传统的Fluvsim程序,使之能刻画复合河道砂体中单一河道砂体的界面;对点坝砂体的模拟可用基于示性点过程的点坝复合砂体Barsim模拟程序,实现了对废弃河道和点坝砂体的模拟;对点坝砂体内部侧积层的模拟采用基于空间矢量的模拟程序Ihssim,以表征点坝内部泥质侧积层的空间分布,最终的构型模型体现了河道砂体不同规模和级次的非均质特征。

A hierarchal nested reservoir architecture simulation methodology is proposed to meet the current challenges in reservoir heterogeneity modeling. It matches the architecture geological research principle which is shortened as ＂hierarchical constraint, pattern fitting and multi-dimension proof＂. In this proposed methodology, different modeling approaches are adopted in different stages of architecture analysis, and the result from current architecture analysis is used as constraints and information for next level architecture analysis. The meandering river reservoir architecture modeling is used to illustrate the proposed methodology. The meandering river sand complex is the first modeling stage. The Fluvsim program is updated to characterize the bounding surface of single channel within the channel sand complex. In second stage, a new point bar simulation program, Barsim, is developed. The abandoned channel and the known point bars are assembled together according to the quantity fluvial reservoir architecture model. The spatial vector based program Ihssim is developed to characterize the inclined heterogeneity strata （IHS） inside the point bar sand at third level architecture study stage. Through such an integrated three modeling procedures, the heterogeneity characteristics of a reservoir which is represented by reservoir architecture elements in different scales and hierarchical levels are presented in the final reservoir model.