Computed-tomography-based discrete fracture-matrix modeling: An integrated framework for deriving fracture networks

Abstract

Investigating the topology of natural fractures and associated flow properties allow for better understanding of fluid flow patterns and mechanical response in fractured reservoirs, key points in the energy supply through geothermal systems, or in the reduction of net CO2 emissions through carbon capture and storage (CCS) practices. However, limited information on the fracture networks is available from seismic data, which poses as a challenge in the accurate modeling of fractured reservoirs. This work proposes an integrated framework for obtaining fracture networks with real aperture distributions, based on X-ray computed tomography (CT) images of core plugs from naturally fractured rock formations. We adapt and employ segmentation, skeletonization and geometry generation algorithms that are available in open-source libraries and licensed software. In addition, we investigate the contributions of fractures and porous matrix to the equivalent permeability tensor through fluid flow simulations considering three different scenarios for the matrix permeability. This work is novel in the coordination of the steps involved in the generation of discrete fracture-matrix (DFM) models from CT-scans of core plugs.