DIX Planetary Science Seminar

Global volcanism has dominated the evolution of many worlds from the early Earth at the time when life emerged, to potentially habitable ocean worlds like Enceladus. By affecting large proportions of planetary interiors, far below the surface expressions that we observe, planetary volcanism leads to thermal, structural, and chemical evolution, and in the case of the Earth, has facilitated life. Io is an extreme ‘end-member' that allows us to study planetary volcanism in relative isolation from other processes. A complete picture of planetary volcanism requires an investigation of volcanic systems in the crust together with magmatic processes in the underlying mantle that fuel them. This is a significant challenge because crustal volcanic systems evolve on much shorter timescales than planetary mantles, which has led previous works to focus on each domain separately. I develop a new parametrisation for the rapid, complex processes of volcanic systems that allow them to be investigated alongside much slower mantle processes. With this approach I propose: a) the formation of magmatic intrusions is a fundamental part of Io's crustal heat balance, and controls the crustal thickness; b) magmatism and volcanism leads to a stratification in Io's mantle, predicting the formation of ultra-high-temperature lava at depth; c) Io's long-wavelength topography and crustal thickness variations can be used to infer the underlying tidal heating distribution.