Geological Modeling for Simulation Studies

Abstract

Reservoir heterogeneity is hierarchical in nature, and different levels of reservoir heterogeneity need to be quantified by the reservoir geologist for numerical simulation studies. At the largest scale, field scale, sand-body continuity and interconnectedness are the most important parameters. At the scale of a reservoir or a genetic sand body, areal permeability trends, presence and distribution of permeability baffles, vertical profiles of permeability, and presence of directional permeability within a sand body are the most critical parameters. At a smaller scale, the influence of cross-bedding on displacement processes is shown to be significant, and, in fact, should be assessed to obtain more meaningful results from larger scale simulation models. The examples given show some of the effects of the different scales of heterogeneity on fluid flow patterns. These examples indicate the degree of detail that must be considered at different scales if simulations are to give meaningful results.