PHASE-DIAGRAM OF IRON BY IN-SITU X-RAY-DIFFRACTION - IMPLICATIONS FOR EARTH CORE

被引：143

作者：

YOO, CS

AKELLA, J

CAMPBELL, AJ

MAO, HK

HEMLEY, RJ

机构：

[1] CARNEGIE INST WASHINGTON, GEOPHYS LAB, WASHINGTON, DC 20015 USA

[2] CARNEGIE INST WASHINGTON, CTR HIGH PRESSURE RES, WASHINGTON, DC 20015 USA

来源：

SCIENCE | 1995年 / 270卷 / 5241期

关键词：

D O I：

10.1126/science.270.5241.1473

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 phase diagram of iron has been studied to 130 gigapascals (1 gigapascal = 10(4) atmospheres) and 3500 kelvin by a combined laser-heated diamond-anvil cell and x-ray diffraction technique that provides direct identification of the solid phases. Iron in the hexagonal close-packed (hcp) phase (epsilon-Fe) is stable from 50 to at least 110 gigapascals at high temperatures. The wide stability field of epsilon-Fe indicates that this polymorph should currently be considered the most relevant solid phase for Earth's core. The triple point between the gamma, epsilon, and liquid phases is located at 2500 +/- 200 kelvin and 50 +/- 10 gigapascals, There is evidence for a phase with a double hcp structure below 40 gigapascals and for another transition above 110 gigapascals and 3000 kelvin.

引用

页码：1473 / 1475

页数：3