Gas Transport Properties and Its Anisotropy of the Shale Matrix — A Review

Abstract

For a number of decades, scientists and engineers have been investigating and describing storage and transport mechanisms in porous media such as reservoir rocks. This work has resulted in the development of concepts such as single phase and multi-phase flow, which describe the movement of fluids in conventional reservoir rock types such as sandstones and carbonates. However, many of these concepts may not be directly applicable to unconventional reservoirs. For example, shale gas reservoirs consist of organic-rich shale matrix, which have high compressibility, very small pore throats, extremely low and anisotropic porosity and permeability. The models developed to describe conventional reservoirs may not accurately describe the processes at work in these rocks. We aim to characterize the transport processes occurring in unconventional reservoirs. We will examine processes occurring at various spatial scales, ranging from fracture flow on the centimeter scale down to slip-flow on the nanometer scale. Due to the softer nature of tight shales, many processes, such as slip-flow and the pore-throat compressibility, will have to be considered as coupled. We collect more than 300 publications and interpret experimental observations in light of this description.

AAPG Datapages/Search and Discovery Article #90216 ©2015 AAPG Annual Convention and Exhibition, Denver, CO., May 31 - June 3, 2015