地化所在高温高压下矿物电性和弹性研究获得新进展

发布时间：2014-08-08

原位的高温高压下矿物岩石电导率和弹性波速为地球科学家探索地球与行星内部物质组成、结构构造、温度分布、部分熔融、水含量、氧化还原状态、点缺陷化学、化学元素迁移、电子自旋态转变等提供极为重要的信息。

多年以来，中科院地化所地球内部物质高温高压实验室李和平研究员课题组一直致力于该方面的研究工作，并取得了重要进展。在李和平研究员指导下，该课题组研究人员代立东、胡海英等以地壳和上地幔典型的矿物岩石：富含铁铝榴石 (Alm₈₂Py₁₅Grs₃)、单晶San Carlos橄榄石及花岗岩，及下地幔矿物：钙铁酸盐相 (Na_0.4Mg_0.6Al_1.6Si_0.4O₄ 的NAL和CF)为例，在本实验室、美国耶鲁大学地质与地球物理系及日本东京工业大学地球与行星科学学院，采用多面顶大压力机和金刚石压腔高温高压设备，结合世界最大同步光源国家实验室的日本SPring-8和双面CO₂镭射激光加热条件下，对电导率和布里渊散射弹性波速进行原位测量，发现压力、氧分压、相转变对矿物物理学性质有重要影响，该成果可为地球深部物质的电导率-深度和弹性波-深度等剖面的建立提供重要的实验结果和科学依据。

该工作得到了中国科学院地球化学研究所135项目、中国国家自然科学基金，部分成果得到了日本学术振兴会外国研究员基金、美国自然科学基金等项目资助。相关成果依次发表在：

[1] Dai Lidong, Hu Haiying, Li Heping*, Jiang Jianjun and Hui Keshi. Influence of temperature, pressure, and chemical composition on the electrical conductivity of granite. American Mineralogist, 2014, in press, doi: http://dx.doi.org /10.2138/am.2014.4692.

[2] Hu Haiying, Dai Lidong, Li Heping*, Jiang Jianjun and Hui Keshi. Electrical conductivity of K-feldspar at high temperature and high pressure. Mineralogy and Petrology, 2014, in press, doi: 10.1007/s00710-014-0325-7.

[3] Dai Lidong and Karato Shun-ichiro*. The effect of pressure on the electrical conductivity of olivine under the hydrogen-rich conditions. Physics of the Earth and Planetary Interiors, 2014, 232: 51-56.

[4] Dai Lidong and Karato Shun-ichiro*. Influence of oxygen fugacity on the electrical conductivity of olivine: Implications for the mechanism of conduction. Physics of the Earth and Planetary Interiors, 2014, 232: 57-60.

[5] Dai Lidong*, Kudo Y, Hirose K, Murakami M, Asahara Y, Ozawa H, Ohishi Y and Hirao N. Sound velocities of Na_0.4Mg_0.6Al_1.6Si_0.4O₄ NAL and CF phases 73 GPa determined by Brillouin scattering method. Physics and Chemistry of Minerals, 2013, 40: 195-201.

[6] Dai Lidong, Li Heping*, Hu Haiying, Jiang Jianjun, Hui Keshi and Shan Shuangming. Electrical conductivity of Alm₈₂Py₁₅Grs₃ almandine-rich garnet determined by impedance spectroscopy at high temperatures and high pressures. Tectonophysics, 2013, 608: 1086-1093.

[7] Hu Haiying, Li Heping*, Dai Lidong, Shan Shuangming and Zhu Chengming. Electrical conductivity of alkali feldspar solid solutions at high temperatures and high pressures. Physics and Chemistry of Minerals, 2013, 40: 51-62.

　 (李和平课题组供稿)