The Quest for Earth's Primordial Geochemical Reservoirs

The Earth was extensively molten in the first 100 million years after its formation. In that span of time, it acquired much of its present-day structure: the metallic core segregated and sank towards the center, while the mantle and crust separated at the surface. The primordial evolution of the mantle and core can be thought of as the most ancient and most global magmatic differentiation event in Earth’s history; it involves the solidification of the molten planet, also known as the “Magma Ocean”. The process and sequence of events that led to the freezing of the “Magma Ocean” is still unknown, and subject to considerable conjecture and speculation. This primordial event left geochemical and geophysical imprints in the crust and in the deep mantle that are still observable today. We want to use these observations to constrain the possible scenarios of Magma Ocean solidification. We will simulate conditions existing in the Early Earth to reproduce the Magma Ocean solidification event in the laboratory using state-of-the-art high pressure/high temperature tools in Paris, in conjunction with groundbreaking microanalytical techniques at Stanford. We will then find the paths to solidification that are compatible with the observables.