Iron-rich post-perovskite and the origin of ultralow-velocity zones

被引：197
作者：
Mao, WL
Mao, HK
Sturhahn, W
Zhao, JY
Prakapenka, VB
Meng, Y
Shu, JF
Fei, YW
Hemley, RJ
机构：
[1] Los Alamos Natl Lab, Lujan Neutron Scattering Ctr, Los Alamos, NM 87545 USA
[2] Carnegie Inst Sci, Geophys Lab, Washington, DC 20015 USA
[3] Argonne Natl Lab, Adv Photon Source, Xray Operat & Res, Argonne, IL 60439 USA
[4] Argonne Natl Lab, High Pressure Collaborat Access Team, Argonne, IL 60439 USA
[5] Univ Chicago, Chicago, IL 60637 USA
来源：
SCIENCE | 2006年 / 312卷 / 5773期
关键词：
D O I：
10.1126/science.1123442
中图分类号：
O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];
学科分类号：
07 ; 0710 ; 09 ;
摘要：
The boundary layer between the crystalline silicate lower mantle and the liquid iron core contains regions with ultralow seismic velocities. Such low compressional and shear wave velocities and high Poisson's ratio are also observed experimentally in post-perovskite silicate phase containing up to 40 mol% FeSiO3 endmember. The iron-rich post-perovskite silicate is stable at the pressure-temperature and chemical environment of the core-mantle boundary and can be formed by core-mantle reaction. Mantle dynamics may lead to further accumulation of this material into the ultralow-velocity patches that are observable by seismology.
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收藏
页码：564 / 565
页数：2
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