Lowell proposes to develop two models for magma-hydrothermal boundary layer heat transfer at ocean ridge crests. One of the models will treat vertical hydrothermal boundary layers that develop adjacent to dikes and rise as plumes to the sea floor. This type of flow may explain ephemeral black smoker activity that appears to occur at the margins of magmatic domes. The second mathematical model concerns heat transfer from a convecting, freezing magma chamber to a hydrothermal system. This model will focus on phase separation of seawater and the formation of a highly saline brine layer at the base of the hydrothermal system, and the subsequent impact of such a layer on the evolution of the magma-hydrothermal system.