Study of Primordial Earth by Means of High-Pressure Experiments

Abstract

In this article, the recent standard scenario for formation of the solar system was briefly reviewed, focusing on accretion of the terrestrial planets. The final stage of accreting Earth is characterized by an impact of a Mars-sized planetary embryo, which results in lunar formation. The giant impact, on the other hand, brings extensive melting to the Earth, and a deep magma ocean covers the early Earth. Therefore the primordial state of the evolving Earth is to be decisively controlled through a cooling process of the magma ocean. Chemical fractionation of the mantle in the magma ocean was discussed based on the results of high-pressure melting experiments on mantle materials up to 35 GPa. Importance of melting experiment on Earth’s materials at higher pressure was emphasized in understanding the evolution of the Earth.