ABSTRACT
Hydraulic fracturing stimulations are routinely performed for commercial recovery of methane from coal seams. Both low (conventional) and abnormally high treatment pressures have been reported. This paper evaluates the fracturing pressure decline after shut-in to detect the mechanisms responsible for the high pressures. Based on the pressure decline behavior, fracturing treatment data, from over 75 coal hydraulic stimulations carried out in the Black Warrior Basin (Alabama), are classified into generic treatment categories.
