High-Pressure Sound Velocity of Perovskite-Enstatite and Possible Composition of Earth5s Lower Mantle  

作　　者：GONG Zi-zheng XIE Hong-sen LIU Yong-gang HUO Hui JING Fu-qian GUO Jie XU Ji-an 龚自正;谢鸿森;刘永刚;霍卉;经福谦;郭捷;徐济安(Material Laboratory of the Earth's Interior,Institute of Geochemistry,Chinese Academy of Sciences,Guiyang 550002;Laboratory for Shock Waves and Detonation Physics Research,Southwest Institute of Fluid Physics,Chengdu 610003;Institute of Geosciences,Academia Sinica,Taipei 11529)

机构地区：[1]Material Laboratory of the Earths Interior,Institute of Geochemistry,Chinese Academy of Sciences,Guiyang 550002 [2]Laboratory for Shock Waves and Detonation Physics Research,Southwest Institute of Fluid Physics,Chengdu 610003 [3]nstitute of Geosciences,Academia Sinica,Taipei 11529

出　　处：《Chinese Physics Letters》1999年第9期695-697,共3页中国物理快报（英文版）

基　　金：the National Natural Science Foundation of China under Grant No.19672058;the Science and Technology Foundation of Chinese Academy of Engineering Physics under Grant No.960103.

摘　　要：The compressional sound velocity vp for enstitate of polycrystalline specimens was measured at pressures from 40 to 140 GPa by using the optical analyzer techniques under shock loading. The dependence of vp (in units of km/s) on Hugoniot pressure p (in units of GPa) can be described by: vp = 3.079 - 0.691 lnp + 0.0941n2p. The vp satisfies Birch's law: vp = 6.213 + 1.212 ρ, where ρ is corresponding density, indicating that enstatite is stable throughout the conditions of the lower mantle. Here P wave velocity is 0.5% lower and S wave velocity is 2% higher than those of preliminary reference earth model, respectively. It is concluded that the lower mantle is mainly composed of perovskite-(Mg1-x,Fex)SiO3 and only small amount of (Mg1-x,Fex)O is allowed in it.

关 键 词：VELOCITY Earth LOWER 

分 类 号：G63[文化科学—教育学]