MgSiO₃ペロブスカイトとポストペロブスカイト相の音速測定

抄録

Brillouin scattering measurements of the aggregate shear wave velocities in MgSiO₃ perovskite and post-perovskite phase were conducted at high-pressure conditions relevant to the Earth’s lowermost mantle. Infrared laser annealing of samples in a diamond anvil cell enabled to obtain high quality Brillouin spectra and to extend the upper limit of pressure of Brillouin measurements. The large pressure range over which acoustic measurements of MgSiO₃ perovskite and post-perovskite phase were performed has thereby allowed us to put tighter constraints on compositional models of the Earth’s lower mantle and enigmatic seismic observations in the lowermost mantle.