Constrain on elastic properties at high P and T of the minerals of the Earth's MTZ

在与地球深部地幔有关的同时高温高压条件下，用超声干涉法研究了地幔过渡带矿物的纵波和横波速度。我们的实验室实验与地震观测的直接比较提供了对地球深部地幔结构的原始见解。结果表明，石榴石中的化学变化很难解释低速区，这表明多次相变和/或相变可能是造成660 km深度不连续面附近地震波分裂的原因。

The P- and S-wave velocities of mantle transition zone minerals were investigated by ultrasonic interferometry in situat simultaneous high pressure and high temperature relevant to the Earth’s deep mantle. The direct comparison of our laboratory experiments with seismic observations gives an original insight into the structure of the Earth’s deep mantle. Our results showed that chemical variation in garnet can hardly explain low velocity regions, which suggest that multiple phase transformation and/or transition could be responsible for splitting of seismic waves near the 660 km depth discontinuity.