固物研究生论坛 -Elasticity of MgSiO3 akimotoite

The thermodynamic and elastic properties of akimotoite in mantle conditions are calculated using first-principles calculations based on density functional theory. The velocities and density of akimotoite are significantly higher than those of majorite and the phase transition from majorite to akimotoite can cause compressional velocity, shear velocity and density to increase by 10.6%, 20.1%, and 5.6% respectively. Besides, the phase transition from akimotoite to bridgmanite can lead to corresponding increase by 4.6%, 8.3%, and 6.6%, which could lead to multiple discontinuities around 660 km in subduction zones combined with the post-spinel transition. Furthermore, the strong anisotropy and crystallographic preferred orientation of akimotoite provide a reasonable way to identify the origin of seismic anisotropy in Tonga subduction zone.