The effect of alumina on the electrical conductivity of silicate perovskite

被引：115

作者：

Xu, YS ^{[1
]}

McCammon, C ^{[1
]}

Poe, BT ^{[1
]}

机构：

[1] Univ Bayreuth, Bayer Geoinst, D-95440 Bayreuth, Germany

来源：

SCIENCE | 1998年 / 282卷 / 5390期

关键词：

D O I：

10.1126/science.282.5390.922

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：

Measurements of the electrical conductivity of silicate perovskite at 25 gigapascals and 1400 degrees to 1600 degrees C show that the conductivity of (Mg,Fe)SiO3 perovskite containing 2.89 weight percent Al2O3 is about 3.5 times greater than that of aluminum-free (Mg0.915Fe0.085)SiO3 perovskite. The conduction mechanism in perovskite between 1400 degrees and 1600 degrees C is most Likely by polarons, because Mossbauer studies show that the aluminum-bearing perovskite has about 3.5 times the amount of Fe3+ as the aluminum-free sample. A conductivity-depth profile from 660 to 2900 kilometers based on aluminum-bearing perovskite is consistent with geophysical models.

引用

页码：922 / 924

页数：3

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