气候变化领域集成服务门户(CCPortal): Pressure Dependence of Proton Incorporation and Water Solubility in Olivine

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DOI	10.1029/2019JB018813
	Pressure Dependence of Proton Incorporation and Water Solubility in Olivine
	Fei H.; Katsura T.
发表日期	2020
ISSN	21699313
卷号	125 期号:2
英文摘要	Hydrous forsterite single crystals were synthesized at 8 GPa and 1250 °C using a multianvil apparatus under various SiO2 activity conditions. Electron microprobe and transmission Fourier-transform infrared spectroscopy analyses show that the Mg/Si atomic ratio increases with increasing water content. This provides new evidence that protons are mainly stored in Si sites in hydrous forsterite. The contribution of Mg sites for proton incorporation can be significant at ≤2.5 GPa with excess SiO2 but is negligible at higher pressures. Protons in olivine under asthenospheric conditions are therefore mostly maintained in Si sites. A summary of experimental studies suggests that the water solubility of forsterite/olivine equilibrated with excess (Mg,Fe)O is substantially higher than that with excess SiO2; however, this difference decreases with increasing pressure and becomes identical at 12–14 GPa. Owing to the low water solubility of olivine under topmost asthenospheric conditions, the geophysically observed low viscosity and low seismic velocity zones cannot be caused by olivine hydration, and the high conductivity anomaly should not be attributed to free H+-controlled proton conduction in olivine. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	incorporation mechanism; Mg/Si ratio; olivine; proton; upper mantle; water solubility
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/188010
作者单位	Bayerisches Geoinstitut, University of Bayreuth, Bayreuth, Germany; Center for High Pressure Science and Technology Advanced Research, Beijing, China
推荐引用方式 GB/T 7714	Fei H.,Katsura T.. Pressure Dependence of Proton Incorporation and Water Solubility in Olivine[J],2020,125(2).
APA	Fei H.,&Katsura T..(2020).Pressure Dependence of Proton Incorporation and Water Solubility in Olivine.Journal of Geophysical Research: Solid Earth,125(2).
MLA	Fei H.,et al."Pressure Dependence of Proton Incorporation and Water Solubility in Olivine".Journal of Geophysical Research: Solid Earth 125.2(2020).