Migration, trapping, and venting of gas in a soft granular material

Abstract

Gas migration through a soft, liquid-saturated granular material involves a strong coupling between the motion of the gas and the deformation of the material. This process is central to many natural and industrial systems, such as the generation and venting of gases from lake beds and waste ponds. Using high-resolution experiments and a simple mechanistic model, grain-scale fluid and solid mechanics are linked with macroscopic migration, trapping, and venting. The largest amount of trapping and the largest venting events are found to occur at intermediate confining stress.