Multiphase flow and granular mechanics

A perspective highlights the recent progress in our understanding of how the interplay between viscous, capillary, and frictional forces shape the interactions of multiphase flow with deformable granular media, with particular attention to the central role of wettability. Beyond their intrinsic interest as processes that give rise to spectacular pattern formation, these coupled phenomena in granular media can control continental-scale fluxes, such as methane venting from the seafloor, and geohazards, such as earthquakes and landslides.