Shock Compression and Phase Transitions of Magnesiowüstite (Mg,Fe)O up to Earth’s Lowermost Mantle Conditions
ZHANG Li1, GONG Zi-Zheng2,1
1Institute of High Pressure and High Temperature Physics, Southwest Jiaotong University, Chengdu 610031
2Beijing Institute of Spacecraft Environment Engineering, Beijing 100094
Shock Compression and Phase Transitions of Magnesiowüstite (Mg,Fe)O up to Earth’s Lowermost Mantle Conditions
ZHANG Li1;GONG Zi-Zheng2,1
1Institute of High Pressure and High Temperature Physics, Southwest Jiaotong University, Chengdu 610031
2Beijing Institute of Spacecraft Environment Engineering, Beijing 100094
Abstract： We report new shock-compression data for polycrystalline (Mg,Fe)O up to 130GPa shock pressures corresponding to Earth’s lowermost mantle conditions. Our data together with the existing shock-wave data of (Mg,Fe)O and its end-members MgO and FeO reveal that the Hugoniot curves of (Mg,Fe)O does not change with varying FeO content for their B1 phase (NaCl-structure) in the pressure--relative-volume plane. The evidence of the volume change within 3% at around 120GPa along the Hugoniot of (Mg0.6, Fe0.4)O is consistent with a structural transition from B1 phase (NaCl cubic) to B8 phase (NiAs-type hexagonal). Such a structural transition of (Mg,Fe)O, if indeed occurs, may in part contribute to the scattering of seismic waves and change in velocity gradient found in the lowermost mantle.
ZHANG Li;GONG Zi-Zheng;. Shock Compression and Phase Transitions of Magnesiowüstite (Mg,Fe)O up to Earth’s Lowermost Mantle Conditions[J]. 中国物理快报, 2006, 23(11): 3049-3051.
ZHANG Li, GONG Zi-Zheng,. Shock Compression and Phase Transitions of Magnesiowüstite (Mg,Fe)O up to Earth’s Lowermost Mantle Conditions. Chin. Phys. Lett., 2006, 23(11): 3049-3051.
2006, Vol. 23 
