Ultrasonic velocities of orthopyroxene and clinopyroxene at high pressure and their geophysical implications
Pyroxene is one of the main rock-forming minerals,and it is the second most abundant mineral in the pyrolite model after olivine.Therefore,the elasticity of pyroxene under high pressure and high temperature is of great significance for understanding the composition of crust-mantle materials,the causes of seismic discontinuities,and dynamic processes in the interior of the Earth.In this study,two natural pyroxenes,orthopyroxene and clinopyroxene,were hot-pressed to obtain polycrystalline aggregates,and their elastic wave velocities under high pressure was obtained through ultrasonic interferometry.Within the pressure range of this study,the wave velocities of orthopyroxene and clinopyroxene both increase with the pressure,but the values of wave velocities in this study are close.Combined the results of this study with previous results on other mantle minerals,velocity profiles of a pyrolite lithology were established using Voigt-Reuss-Hill(VRH)calculation.The calculated results were compared to the PREM model to constrain the composition of the mantle.
High pressureOrthopyroxeneClinopyroxeneUltrasonic velocitiesPyrolite model
万方数据
维普
