A post-stishovite SiO2 polymorph in the meteorite Shergotty:: Implications for impact events

被引：117

作者：

Sharp, TG ^{[1
]}

El Goresy, A

Wopenka, B

Chen, M

机构：

[1] Arizona State Univ, Dept Geol, Tempe, AZ 85287 USA

[2] Max Planck Inst Kernphys, D-69029 Heidelberg, Germany

[3] Washington Univ, Dept Earth & Planetary Sci, St Louis, MO 63130 USA

[4] Acad Sinica, Guangzhou Inst Geochem, Guangzhou 510640, Peoples R China

来源：

SCIENCE | 1999年 / 284卷 / 5419期

关键词：

D O I：

10.1126/science.284.5419.1511

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：

Transmission electron microscopy and electron diffraction show that the martian meteorite Shergotty, a shocked achondrite, contains a dense orthorhombic SiO2 phase similar to post-stishovite SiO2 with the alpha-PbO2 structure. If an SiO2 mineral exists in Earth's Lower mantle, it would probably occur in a post-stishovite SiO2 structure, The presence of such a high-density polymorph in a shocked sample indicates that post-stishovite SiO2 structures may be used as indicators of extreme shock pressures.

引用

页码：1511 / 1513

页数：3

共 38 条

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