The combination of hydraulic fracturing and depressurization method has been proposed to enhance gas production efficiency from methane hydrate (MH) reservoirs. To evaluate the efficacy of this method, we construct a fractured MH reservoir model and investigate by means of numerical simulation the gas production behaviors under two different temperature conditions. The simulation results indicate that the combination of hydraulic fracturing and depressurization method is more efficient for gas production than the single depressurization method. For the high-temperature reservoir, the hydrate dissociation and gas production during the early depressurization stage can be significantly enhanced after fracturing, and the effect of increasing the size and permeability of the fractured zone on gas production rate is more remarkable in the early depressurization stage than in the late depressurization stage. For the low-temperature reservoir, while the improvement in hydrate dissociation and gas production by fracturing is dramatic during the entire depressurization period, the increment in total gas production is very low in absolute terms. In addition, gas production from low-temperature reservoir is very sensitive to initial temperature, and increasing the reservoir temperature can enhance the benefits of fracturing.
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