气候变化领域集成服务门户(CCPortal): Oxygen Vacancy Substitution Linked to Ferric Iron in Bridgmanite at 27 GPa

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DOI	10.1029/2019GL086296
	Oxygen Vacancy Substitution Linked to Ferric Iron in Bridgmanite at 27 GPa
	Fei H.; Liu Z.; McCammon C.; Katsura T.
发表日期	2020
ISSN	0094-8276
卷号	47 期号:6
英文摘要	Ferric iron can be incorporated into the crystal structure of bridgmanite by either oxygen vacancy substitution (MgFeO2.5 component) or charge-coupled substitution (FeFeO3 component) mechanisms. We investigated the concentrations of MgFeO2.5 and FeFeO3 in bridgmanite in the MgO-SiO2-Fe2O3 system at 27 GPa and 1700–2300 K using a multianvil apparatus. The FeFeO3 content increases from 1.6 to 7.6 mol.% and from 5.7 to 17.9 mol.% with and without coexistence of (Mg,Fe)O, respectively, with increasing temperature from 1700 to 2300 K. In contrast, the MgFeO2.5 content does not show clear temperature dependence, that is, ~2–3 and < 2 mol.% with and without the coexistence of (Mg,Fe)O, respectively. Therefore, the presence of (Mg,Fe)O enhances the oxygen vacancy substitution for Fe3+ in bridgmanite. It is predicted that Fe3+ is predominantly substituted following the oxygen vacancy mechanism in (Mg,Fe)O-saturated Al-free bridgmanite when Fe3+ is below ~0.025 pfu, whereas the charge-coupled mechanism occurs when Fe3+ > 0.025 pfu. ©2020. The Authors.
英文关键词	Crystal structure; Hematite; Iron; Magnesia; Oxygen; Silica; Temperature distribution; bridgmanite; Coupled substitution; Ferric iron; Increasing temperatures; Lower mantle; Multi-anvil apparatus; Temperature dependence; Vacancy mechanisms; Oxygen vacancies; concentration (composition); crystal structure; iron; lower mantle; temperature effect
语种	英语
来源期刊	Geophysical Research Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/170571
作者单位	Bayerisches Geoinstitut, University of Bayreuth, Bayreuth, Germany
推荐引用方式 GB/T 7714	Fei H.,Liu Z.,McCammon C.,et al. Oxygen Vacancy Substitution Linked to Ferric Iron in Bridgmanite at 27 GPa[J],2020,47(6).
APA	Fei H.,Liu Z.,McCammon C.,&Katsura T..(2020).Oxygen Vacancy Substitution Linked to Ferric Iron in Bridgmanite at 27 GPa.Geophysical Research Letters,47(6).
MLA	Fei H.,et al."Oxygen Vacancy Substitution Linked to Ferric Iron in Bridgmanite at 27 GPa".Geophysical Research Letters 47.6(2020).