Hydrogeology of fractured media - With special reference to coalbeds

The flow of fluids in fractured coal seams exerts control on the accumulation of methane, its storage and then recovery. All of these fluids are stored and transported in the fractured coal seam and conform to similar physical laws: those controlling the storage and transport of fluids in fractured media. Understanding rates of fluids recovered from coalbeds requires the permeability and storage characteristics to be accurately and reliably determined at relevant scales. A key feature in understanding the hydrogeology of coal seams, particularly the recovery of gases from such units is the extreme stress sensitivity of permeability. Contemporary uses of coalbeds relate to their degasification for mining safety, as a resource, and for their potential use for the sequestration of CO₂ and storage of H₂. The particular behavior of coals, with the discrete structure of the matrix and cleats conditions its response as a dual porosity material.