Representative Pore-network Model for a Multiscale Dolomite

Abstract

A multi-scale network integration approach (Jiang et al. [2013]) is used to generate a representative pore-network model (PNM) for a carbonate rock with a pore-size distribution spanning across several orders of magnitude. We explore single-scale, two-scale, and three-scale network models and discuss their representativeness by comparing simulated capillary-pressure versus saturation curves with laboratory measurements derived from mercury injection porosimetry. In this work PNMs extracted from μCT images acquired at different length-scales are integrated into single multi-scale PNMs to incorporate all the porosity features that exist in the rock. We present a workflow for effective selection of appropriate length-scales for generation of the multi-scale network. The choice of images to be combined is informed by MICP throat-size distributions. Here, the integrated networks were used to reproduce Pc(S) curves, evaluated against MICP laboratory measurements. We demonstrate that Pc(S) curves calculated based on the two scale and three-scale PNMs provide significantly closer comparisons to the laboratory measurements compared to a single-scale network model.