Dependence of Shale Permeability on Pressure

In this paper, an equation relating shale permeability to pressure and geomechanical properties is derived. This is important because the success of shale gas and oil developments depends on increasing fracture-based permeability with pressure caused by fluid injection. A simple equation relating shale permeability to pressure, Young's modulus (a measure of the elasticity of the shale), and Poisson's ratio is derived from the basic conservation of-momentum equation. The use of this equation to predict shale permeability and, hence, the likely success of fracturing for any particular shale, on the basis of measured geomechanical properties is discussed.