The gas–water flow capacity has a significant impact on the production of coalbed methane wells. Gas–water two-phase flow occurs throughout various stages of coalbed methane development, and spontaneous imbibition is a phenomenon observed in nearly all hydrophilic coal reservoirs. However, systematic studies on reservoir permeability damage caused by imbibition and its influencing factors are still lacking, and no definitive conclusions have been drawn.

In the petroleum and porous media fields, low-field nuclear magnetic resonance (NMR) technology is playing an increasingly important role. It can be used not only for conventional evaluations such as exploration and development of low-permeability oilfields, gas fields, and coalbed methane, but also, with NMR imaging techniques, for non-destructive and rapid assessment of internal rock pore distributions and spatial fluid saturations.

Recovery factor (or oil recovery rate) is an important indicator for evaluating the development level of an oilfield. It refers to the ratio of the amount of oil that can be extracted from a reservoir under modern technological and economic conditions to the total geological reserves.