IGGCAS OpenIR  > 地球与行星物理院重点实验室
Magnesium partitioning between silicate melt and liquid iron using first-principles molecular dynamics: Implications for the early thermal history of the Earth's core
Liu, Weiyi1,5; Zhang, Yigang1,2; Yin, Qing-Zhu3; Zhao, Yong1,4,5; Zhang, Zhigang1,4,5
2020-02-01
Source PublicationEARTH AND PLANETARY SCIENCE LETTERS
ISSN0012-821X
Volume531Pages:12
AbstractThe high conductivity of the Earth's core discovered through first-principles and experimental studies requires that the core must start very hot and cool down slowly to generate the Earth's magnetic field by thermal buoyancy. The requirement is difficult to satisfy due to the fast cooling of the overlying magma ocean and consequently of the underlying core. This is in direct conflict with the early appearance of the Earth's paleomagnetic field. Recently, it was proposed that significant amount of magnesium (Mg) can be partitioned into the core through the high temperature created by the Moon-forming Giant Impact. Due to its intrinsic low solubility, subsequent cooling would cause Mg precipitation to generate compositional buoyancy to power the geodynamo in the early history of the Earth. Here we show using first-principles molecular dynamics simulations that the equilibrium constant of magnesium dissolution in molten iron depends on temperature, entirely consistent with recent experimental data. We further show that Mg partitioned into the core during giant impacts and reaching a concentration of about 2 wt% can precipitate out at around 3.5 Ga, much earlier than the onset of inner core nucleation. During the subsequent evolution of the Earth, silicon (Si) concentration of the Earth's core will remain constant while Mg and oxygen (O) concentrations decrease significantly. Consequently, the current Si concentration in the core reflects the accretion processes of the Earth while O and Mg concentrations in the core is the combined result of both accretion and the subsequent evolution of the Earth core. Forward modeling shows that for MgO precipitation to provide enough power to generate the magnetic field in the early history of the Earth, initially high silicon content of the core is preferred, which is accommodated readily in the Grand Tack accretion scenario. The geodynamo driven by MgO precipitation explains the secular decline of palaeomagnetic field intensity in the early history of the Earth. (C) 2019 Elsevier B.V. All rights reserved.
Keywordgeodynamo Mg core ab initio paleomagnetism giant impact
DOI10.1016/j.epsl.2019.115934
Funding OrganizationStrategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; National Science Foundation of China ; National Science Foundation of China ; National Science Foundation of China ; National Science Foundation of China ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; National Science Foundation of China ; National Science Foundation of China ; National Science Foundation of China ; National Science Foundation of China ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; National Science Foundation of China ; National Science Foundation of China ; National Science Foundation of China ; National Science Foundation of China ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; National Science Foundation of China ; National Science Foundation of China ; National Science Foundation of China ; National Science Foundation of China
WOS KeywordHIGH-PRESSURE ; ELECTRICAL-RESISTIVITY ; MOLTEN IRON ; OXYGEN ; CONSTRAINTS ; EVOLUTION ; POTASSIUM ; NI ; DIFFERENTIATION ; PRECIPITATION
Language英语
Funding ProjectStrategic Priority Research Program (B) of the Chinese Academy of Sciences[XDB18000000] ; National Science Foundation of China[41273078]
Funding OrganizationStrategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; National Science Foundation of China ; National Science Foundation of China ; National Science Foundation of China ; National Science Foundation of China ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; National Science Foundation of China ; National Science Foundation of China ; National Science Foundation of China ; National Science Foundation of China ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; National Science Foundation of China ; National Science Foundation of China ; National Science Foundation of China ; National Science Foundation of China ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; Strategic Priority Research Program (B) of the Chinese Academy of Sciences ; National Science Foundation of China ; National Science Foundation of China ; National Science Foundation of China ; National Science Foundation of China
WOS Research AreaGeochemistry & Geophysics
WOS SubjectGeochemistry & Geophysics
WOS IDWOS:000510947100008
PublisherELSEVIER
Citation statistics
Cited Times:1[WOS]   [WOS Record]     [Related Records in WOS]
Document Type期刊论文
Identifierhttp://ir.iggcas.ac.cn/handle/132A11/95676
Collection地球与行星物理院重点实验室
Corresponding AuthorYin, Qing-Zhu
Affiliation1.Chinese Acad Sci, Inst Geol & Geophys, Key Lab Earth & Planetary Phys, Beijing 100029, Peoples R China
2.Univ Chinese Acad Sci, Coll Earth & Planetary Sci, Key Lab Computat Geodynam, Beijing 100049, Peoples R China
3.Univ Calif Davis, Dept Earth & Planetary Sci, Davis, CA 95616 USA
4.Univ Chinese Acad Sci, Beijing 100049, Peoples R China
5.Chinese Acad Sci, Innovat Acad Earth Sci, Beijing 100029, Peoples R China
First Author AffilicationInstitute of Geology and Geophysics, Chinese Academy of Sciences
Recommended Citation
GB/T 7714
Liu, Weiyi,Zhang, Yigang,Yin, Qing-Zhu,et al. Magnesium partitioning between silicate melt and liquid iron using first-principles molecular dynamics: Implications for the early thermal history of the Earth's core[J]. EARTH AND PLANETARY SCIENCE LETTERS,2020,531:12.
APA Liu, Weiyi,Zhang, Yigang,Yin, Qing-Zhu,Zhao, Yong,&Zhang, Zhigang.(2020).Magnesium partitioning between silicate melt and liquid iron using first-principles molecular dynamics: Implications for the early thermal history of the Earth's core.EARTH AND PLANETARY SCIENCE LETTERS,531,12.
MLA Liu, Weiyi,et al."Magnesium partitioning between silicate melt and liquid iron using first-principles molecular dynamics: Implications for the early thermal history of the Earth's core".EARTH AND PLANETARY SCIENCE LETTERS 531(2020):12.
Files in This Item:
There are no files associated with this item.
Related Services
Recommend this item
Bookmark
Usage statistics
Export to Endnote
Google Scholar
Similar articles in Google Scholar
[Liu, Weiyi]'s Articles
[Zhang, Yigang]'s Articles
[Yin, Qing-Zhu]'s Articles
Baidu academic
Similar articles in Baidu academic
[Liu, Weiyi]'s Articles
[Zhang, Yigang]'s Articles
[Yin, Qing-Zhu]'s Articles
Bing Scholar
Similar articles in Bing Scholar
[Liu, Weiyi]'s Articles
[Zhang, Yigang]'s Articles
[Yin, Qing-Zhu]'s Articles
Terms of Use
No data!
Social Bookmark/Share
Add to CiteULike Add to Connotea Add to Del.icio.us Add to Digg Add to Reddit Add to Technorati
All comments (0)
No comment.
 

Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.