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Gas and water flow rates shape the economic feasibility of hydrate deposit exploration. However, pore-scale controls on the gas and water transport as well as ensued impacts on gas production from hydrate deposits have not been well understood. This study uses 3D pore network modeling to understand the impacts of pore characteristics, hydrate, and hysteresis on two-phase fluid transport in hydrate-bearing sediments. The results highlight that drying and wetting are occurring simultaneously in sediments resulting in a nonunique water retention curve. The relative permeability to gas is governed by the coefficient of variance and the connectivity of pore size distribution in sediments. Parameter values for the modified Brook-Corey relative permeability model are recommended considering preferential hydrate pore clogging habits.

Plain Language Summary Economic exploitation of natural hydrate deposits largely depends on the gas and water production rates. However, the gas and water flow models used in current gas production simulations lack rationales in determining their parameter values. This study uses pore network modeling to investigate how various factors, including pore size distribution, pore connectivity, hydrate saturation, and hydrate pore clogging habits, can affect the gas and water flow. The results offer elegant relations to determine the parameter values for gas and water flow in hydrate-bearing sediments.