Shale Permeability

Introduction

Shale is often described as having low bulk matrix permeability, which can be in the range of micro to nano-Darcy (as shown below). As a result, stimulation is often required to produce gas and liquids at economical rates.

Permeability in shales can also vary with confining pressure (or effective stress) in the reservoir. The depletion of the reservoir causes most of the overburden stress to be supported by the confining pressure in the grains resulting in reduction of permeability.

References:

• Ali, Waqas “Modelling Gas Production from Shales and Coal-Beds“, M. Sc Thesis, Stanford University, October 2012.