Internal evolution and magnetic field generation in rocky planets

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My research consists of dynamics of Earth’s core, and the analysis of the evolution and longevity of magnetic activity on rocky planets beyond the solar system (i.e., exoplanets) having different masses and iron contents. I have focused on a specific boundary layer of Earth’s core, the so-called F-layer. Using current knowledge related to seismology, mineral physics, and geodynamics I have put together a model assessing the feasibility of several binary compositions of Earth’s core in matching present seismic observations, as well as their implications on the dynamics of Earth’s core. This study has been presented at several conferences (AGU, JpGU). The main finding of this study is that carbon and sulfur are likely not present as major alloying components in Earth’s core, whereas silicon and oxygen are two potential candidates. Their predominance in Earth’s core provides interesting implications for the driving force of convection in the liquid outer core, which is of thermal origin in the presence of oxygen and driven by chemical buoyancy for a silicon-rich core.I also developed a code describing the thermal evolution of the cores of rocky planets having different mass and iron content. This code has been used to analyze planetary core structures after accretion, as well as the evolution and lifetime of a magnetic field, and accepted to Journal of Geophysical Research: Planets. The main finding of this study is that both the bulk and mantle iron content are strongly determining the magnetic field lifetime of rocky planets.