在温度750~1600K和压力10-20GPa条件下,借助于Kawai-5000多面顶砧高温高压设备,就位测量了(Mg0.9Fe0.1)SiO3顽火辉石的电导率.实验结果显示,顽火辉石的电导率在高温区以小极化子机制为主,在低温区以质子导电为主,因为实验后的样品中有一定的水含量.另外,X射线衍射实验表明压力(20GPa)诱发了顽火辉石向林伍德石的相变,这是我们首次在顽火辉石的电导率实验中观测到林伍德石含水相变,而且含水林伍德石的电导率与已有的实验结果相当一致.
The electrical conductivity of (Mg0. 9Fe0.1) SiO3 enstatite has been measured at pressures of 10-20 GPa and temperatures of 750-1600 K using a Kawai-type multianvil high-pressure apparatus. The experimental results demonstrate that there are two conduction mechanisms, small polaron is the dominant mechanism in the high temperature regions, while proton is in charge of the low temperature regions as water is determined in the recovered sample in this study. On the other hand, we observe a pressure induced phase transition from enstatite to ringwoodite under pressure of 20 GPa by X-ray diffraction. The conductivity of ringwoodite with water at 20 GPa is in good agreement with the available measurements of hydrous ringwoodite.