Melt migration in the Earth

Most of the phenomena studied by geologists and geochemists are due, at least in part, to the ability of fluids to migrate within the Earth's interior. Three processes are believed to operate in melt migration: diapirism (large buoyant masses of partially molten rock, rising by viscously deforming the surrounding solid rock), magmafracturing (the rapid migration of melt along macroscopic fissures in cold rock) and two-phase flow in porous media (the microscopic percolation of buoyant melt in a partially molten rock, and an essential precursor to the other two processes). As a recent paper by McKenzie shows, it is in understanding the third of these processes that the most significant recent developments have occurred.