The system iron-enstatite-water at high pressures and temperatures—formation of iron hydride and some geophysical implications |
| |
Authors: | Toshihiro Suzuki Syun-iti Akimoto Yuh Fukai |
| |
Institution: | Institute for Solid State Physics, University of Tokyo, Minatoku, Tokyo 106 Japan;Department of Physics, Chuo University, Bunkyo-ku, Tokyo 112 Japan |
| |
Abstract: | The system iron-enstatite-water was investigated at pressures around 5 GPa and at temperatures ranging from 1000 to 1200°C, using several different kinds of starting materials. Quenched samples showed the coexistence of iron, olivine and pyroxene. Synthesis of the Fe-containing olivine in the run products proves that a series of reactions, Fe + H2O → FeHx + FeO and FeO + MgSiO3 → (Mg, Fe)2SiO4, have taken place. Spherical “balls of iron” were observed in the 1200°C run. This strongly indicates that the melting temperature of iron decreased by ~ 500 K by the possible dissolution of hydrogen. Following geophysical implications are derived from these experimental results. If water was retained in the hydrous minerals in the primordial material, the iron-water reaction is expected to occur throughout the core-formation process. The reaction product FeHx will melt and then sink to form a proto-core and iron oxide will be dissolved in the Earth's mantle. The dissolution of hydrogen in the Earth's core is a natural consequence of the core-formation process. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|