Multi-scale experimental and numerical simulation workflow of absolute permeability in heterogeneous carbonates

Digital Rock Physics (DRP) is a field that makes use of recent advances in imaging technology and computational methods to determine several rock properties by running numerical simulations on 3D rock images. In this work, DRP tools were used in a novel multi-scale approach that combined micro and macro computations to determine permeability for comparison with lab experiments of 2 different samples at 2 different sizes; 0.5 inch diameter and the standard 1.5 inch diameter. The Lattice Boltzmann Method (LBM) was used to perform micro-scale computations on subvolumes of images at high-resolution images. This was done to determine the permeability, and extract porosity-permeability trends. Then, a macro-scale computational grid was set to have porosity and permeability values from the micro-scale simulations in order to compute the upscaled effective permeability which could then be compared to experimental results. The workflow was first applied to a standard Silurian Dolomite to validate it and then applied to a carbonate sample from an Abu Dhabi reservoir that exhibited a higher level of heterogeneity.