本项目拟选择上地幔主要矿物斜方辉石作为研究对象，重点研究高温高压下水和化学组成对流变学和弹性性质的影响。流变学实验主要在Paterson装置上进行，辅之以Griggs装置和D-DIA装置，围压设定为300-450MPa和1-7GPa，温度1200-1600K，应变速率10-4-10-6s-1；通过研究流变强度随温度、压力、水含量和化学组成（Fe、Al）的变化规律，计算出应力指数、活化能、水逸度指数和活化体积等流变方程参数，同时研究变形的显微构造和组构型式。弹性测量实验采用外加热金刚石压腔布里渊散射技术进行，实验压力为0-15GPa，温度为室温-1000K，通过测量弹性波速及其随压力、温度、水和化学组成变化的规律，计算一整套的单晶弹性系数、弹性模量和波速各项异性数据。研究结果将有助于理解斜方辉石在上地幔的流变行为，厘定斜方辉石和橄榄石的相对强弱，解读地球物理观测事实并约束上地幔的动力学机制。

Rheological and elastic properties of upper mantle minerals are of essential importantance to understand the chemical composition and dynamics process in upper mantle such as lithosphere and asthenosphere. In this project, we plan to investigate the rheological property and elasticity of orthopyroxene under high-pressure and high-temperature. We will focus on the effect of pressure, temperature, chemical component (Fe,Al) and water content on the flowing strength and elasticity of othopyroxene. Rheological experiments will be conducted at a temperature of 1200-1600 K and confining pressures of 300-450 MPa using the Paterson mechanical testing machine and at confining pressure of 1-7GPa using Griggs and D-DIA deformation apparatuses, and the strain rate will be controlled in the range of 10-4 to 10-6 s-1. Elasticity experiments will be conducted using Brillouin scattering combined with external-heating DAC at pressure of 0-15 GPa and temperature of RT-1000K. The experimental data will be used to analyze the relative strength between olivine and orthopyroxene and the elastic velocities and anisotropy of orthopyroxene. The results of this project will provide new experimental constrains on the rheological profile, chemical composition and dynamics process in the upper mantle.