Metal-silicate partitioning experiments: insights on Earth’s differentiation

Earth’s core-mantle differentiation is the most important chemical fractionation in the
planet’s history. The bulk composition of both the mantle and the core are believed to have
been established during accretion, which started about 4.56 billion years ago and lasted at
least many tens of millions of years. The last chemical equilibration between the young mantle and core happened at the base of a deep magma ocean that was covering the entire Earth.
The pressure and temperature conditions at the base of this magma ocean are thought to
have been extreme (> 40 GPa and > 3000 K). In the lab, the only static tool able to reproduce these conditions is diamond anvil cell coupled with a laser heating system.
In this talk, I will present experiments conducted using such a device to investigate the effect
of core formation on the partitioning between metal and silicate of various types of elements
(siderophile, radioactive and/or volatile elements).