The mantles of Earth and other rocky planetary bodies may have been partly or fully molten early in their histories because of the energy of accretion, decay of short-lived radioisotopes, core differentiation, and giant impacts. These “magma oceans” played a fundamental role in early planetary evolution. Exchange between magma oceans and the atmosphere and core may have established the distribution of elements among major planetary reservoirs, while the evolution of magma oceans as they crystallized determined the initial thermal and chemical structure of planetary mantles. Understanding the magma ocean stage is therefore essential for reconstructing the initial conditions for the evolution of rocky planets and the formation of habitable environments. Furthermore, this early stage can be constrained by detecting its subtle fingerprints preserved in the geological records of Earth and other terrestrial planetary bodies and through astronomical observations of atmospheres of exoplanets with present-day magma oceans. Magma oceans have been an active topic of research as rapid developments in laboratory, computational, numerical, and observational capabilities push the boundaries of research closer to the conditions of this extreme stage of planetary evolution.
This session welcomes contributions on all aspects of magma oceans; relevant topics include magma ocean formation, the fluid dynamics and geochemistry/petrology of magma ocean evolution and crystallization, exchange between a magma ocean and other planetary reservoirs including degassing and core-mantle equilibration, and characterization of magma oceans based on evidence retained in the geological and magmatic records of planetary bodies. This session emphasizes exchange across disciplines and scales by inviting research employing a broad spectrum of experimental, observational, analytical, computational, and numerical approaches, such as laboratory experiments (e.g., diamond anvil cell, shock compression, tank fluid dynamics); geochemical and isotopic analyses of minerals and rocks; scaling and stability analyses; ab initio calculations and molecular dynamics simulations; and modeling (e.g., multiphase flow, smooth particle hydrodynamics, atmospheric chemistry). Contributions combining different techniques, comparing different planets, and making links between the magma ocean stage and observables in the planetary record are particularly encouraged.