Pressure-induced magnetic transition and sound velocities of Fe3C:: Implications for carbon in the Earth's inner core

被引：69

作者：

Gao, Lili ^{[1
,2
]}

Chen, Bin ^{[1
]}

Wang, Jingyun ^{[1
]}

Alp, Esen E. ^{[2
]}

Zhao, Jiyong ^{[2
]}

Lerche, Michael ^{[2
,4
]}

Sturhahn, Wolfgang ^{[2
]}

Scott, Henry P. ^{[3
]}

Huang, Fang ^{[1
]}

Ding, Yang ^{[4
,5
]}

Sinogeikin, Stanislav V. ^{[5
]}

Lundstrom, Craig C. ^{[1
]}

Bass, Jay D. ^{[1
]}

Li, Jie ^{[1
]}

机构：

[1] Univ Illinois, Dept Geol, Urbana, IL 61801 USA

[2] Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA

[3] Indiana Univ, Dept Phys & Astron, South Bend, IN 46634 USA

[4] Carnegie Inst Washington, High Pressure Synerget Consortium, Argonne, IL USA

[5] Carnegie Inst Washington, HPCAT & Geophys Lab, Argonne, IL USA

来源：

GEOPHYSICAL RESEARCH LETTERS | 2008年 / 35卷 / 17期

关键词：

D O I：

10.1029/2008GL034817

中图分类号：

P [天文学、地球科学];

学科分类号：

07 ;

摘要：

We have carried out nuclear resonant scattering measurements on (57)Fe-enriched Fe(3)C between 1 bar and 50 GPa at 300 K. Synchrotron Mossbauer spectra reveal a pressure-induced magnetic transition in Fe3C between 4.3 and 6.5 GPa. On the basis of our nuclear resonant inelastic X-ray scattering spectra and existing equation-of-state data, we have derived the compressional wave velocity V(P) and shear wave velocity VS for the high-pressure nonmagnetic phase, which can be expressed as functions of density (rho): V(P)(km/s) = -3.99 + 1.29 rho(g/cm(3)) and V(S)(km/s) = 1.45 + 0.24 rho(g/cm(3)). The addition of carbon to iron-nickel alloy brings density, V(P) and V(S) closer to seismic observations, supporting carbon as a principal light element in the Earth's inner core.

引用

页数：5

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