The 6th International Conference on Matter and Radiation at Extremes (ICMRE2023)

47 / 2023-04-10 08:57:30

Melting relations in the system MgO-SiO2 at extreme conditions

High Pressure Physics and Materials Science > High-pressure geoscience-II

The system MgO-SiO₂ is a good model for the interiors of rocky planets including super-Earths. The phase transitions and melting in the system guide the planetary evolutions by and during planetary collisions. As a result the system has been intensively studied through experimental and theoretical simulations, but the current status of melting relations remains open at very high pressures yet.

Here we compare the sound speed data in the system MgO-SiO₂ and introduce our new in-situ XRD experiments on single crystal Mg₂SiO₄ shocked above 200 GPa using the high-power laser facility SG III-prototype in China. We discuss the melting behaviours in the system MgO-SiO₂ at pressures over ~200 GPa, including forsterite and enstatite compositions.