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Solubilities of O and Si in liquid iron in equilibrium with (Mg,Fe)SiO 3 perovskite and the light elements in the core
Author(s) -
Takafuji Naoto,
Hirose Kei,
Mitome Masanori,
Bando Yoshio
Publication year - 2005
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2005gl022773
Subject(s) - dissolution , diamond anvil cell , materials science , transmission electron microscopy , perovskite (structure) , inner core , analytical chemistry (journal) , outer core , mineralogy , crystallography , chemistry , high pressure , nanotechnology , thermodynamics , physics , chromatography , composite material
Chemical reaction between liquid iron and (Mg,Fe)SiO 3 perovskite was investigated by a combination of laser‐heated diamond anvil cell (LHDAC) and analytical transmission electron microscope (TEM). The compositions of quenched liquid iron in contact with perovskite were determined quantitatively using both energy‐dispersive (EDS) and electron energy loss (EELS) spectra. Results demonstrate that the dissolution both of O and Si into molten iron is significantly enhanced with increasing pressure. The quenched liquid iron contains 5.3 wt% O and 2.8 wt% Si at 97 GPa and 3150 K that can account for the 7% core density deficit. Reaction products such as SiO 2 , FeSi, and FeO were not observed as stable phases in this study. The bottom of the mantle in contact with outer core liquid could be depleted in iron. O and Si are important light elements in the core, whose contents may have increased over the geological time.