本项目拟采用先进的Paterson气体介质高温高压流变仪和D-DIA固体介质流变仪重点研究在单轴压缩条件下上地幔主要矿物组成橄榄石+顽火辉石二元相体系的流变学性质。在深入研究顽火辉石的基础上，探讨顽火辉石含量、水含量对橄榄石+顽火辉石体系的流变性质的影响及其压力效应-即活化体积。实验的围限压力设定为300MPa（Paterson装置） 和3-7GPa（D-DIA装置），温度范围为1200-1600K，应变速率为10-4-10-6s-1。通过SEM、TEM 和EBSD 等手段观察实验产物的显微构造特征、组构型式和变形机制。根据获得的实验数据定量地分析该二元相体系的流变学行为随压力、温度、辉石含量和水含量和的变化规律，建立流变方程。研究结果将会对我们认识软流圈和岩石圈地幔的流变学行为以及构造演化的动力学机制提供新的实验约束。

Rheological behavior of upper-mantle rocks is of important significance for understanding the strength of asthenosphere,the mechanics of lithosphere and the dynamics process of tectonic evolution in upper mantle. In present project, we plan to investigate the rheological properties of olivine + enstatite aggregates, which are composed of two major upper-mantle minerals, under uniaxial compression at confining pressures of 300 MPa using the Paterson high pressure testing machine and of 3-7 GPa using D-DIA apparatus. On the basis of a detailed study of enstatite, we will mainly concern with the effect of enstatite content, water content and confining pressure on the rheological properties of olivine + enstatite aggregates. The temperature and strain rate of experiments are controlled in the range of 1200-1600K 10-4－10-6s-1 respectively. SEM, TEM and EBSD techniques are used to study the microstructural feature, CPO pattern and deformation mechanism of run products. Experimental data will be analyzed quantitatively to quantify the rheological behavior of this two-phase mineral assemblage in the upper mantle and hence try to establish its rheological constitutive equations. The results of this project will provide new experimental constrains on the rheological behavior of asthenosphere, lithosphere as well as dynamic processes occurring in upper mantle.