气候变化领域集成服务门户(CCPortal): Formation of Amphibole-Bearing Peridotite and Amphibole-Bearing Pyroxenite Through Hydrous Melt-Peridotite Reaction and In Situ Crystallization: An Experimental Study

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DOI	10.1029/2020JB019382
	Formation of Amphibole-Bearing Peridotite and Amphibole-Bearing Pyroxenite Through Hydrous Melt-Peridotite Reaction and In Situ Crystallization: An Experimental Study
	Wang C.; Liang Y.; Xu W.
发表日期	2021
ISSN	21699313
卷号	126 期号:3
英文摘要	Amphibole is a common hydrous mineral in mantle rocks. To better understand processes leading to the formation of amphibole-bearing peridotites and pyroxenites in the lithospheric mantle, we conducted experiments by juxtaposing a lherzolite against hydrous basaltic melts in Au-Pd capsules. Two melts were examined, a basaltic andesite and a basalt, each containing 4 wt% of water. The experiments were run at 1200°C and 1 GPa for 3 or 12 h, and then cooled to 880°C and 0.8 GPa over 49 h. The reaction at 1200°C produced a melt-bearing orthopyroxenite-dunite sequence. Crystallization of the partially reacted melts during cooling lead to the formation of an amphibole-bearing gabbronorite-orthopyroxenite-peridotite sequence. Orthopyroxene in the peridotite and orthopyroxenite has a poikilitic texture enclosing olivines and spinels. Amphibole in the peridotite occurs interstitial to olivine, orthopyroxene, clinopyroxene, and spinel. Comparisons of texture and mineral compositions in the experimental products with those from field observations allow a better understanding of hydrous melt-rock reaction in the lithospheric mantle. Amphibole-bearing pyroxenite veins (or dikes) can be formed in the lithospheric mantle or at the crust-mantle boundary by interaction between hydrous melt and peridotite and subsequent crystallization. Hornblendite or amphibole gabbronorite can be formed in the veins when the flux of hydrous melt is high. Differences in reacting melt and peridotite compositions are responsible for the variation in amphibole composition in mantle xenoliths from different tectonic settings. The extent of melt-rock reaction is a factor that control amphibole composition across the amphibole-bearing vein and the host peridotite. © 2021. American Geophysical Union. All Rights Reserved.
英文关键词	amphibole-bearing peridotite; amphibole-bearing pyroxenite; hydrous melt; mantle metasomatism; mantle xenolith; melt-peridotite reaction
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/187300
作者单位	College of Earth Sciences, Jilin University, Changchun, China; Department of Earth, Environmental and Planetary Sciences, Brown University, Providence, RI, United States
推荐引用方式 GB/T 7714	Wang C.,Liang Y.,Xu W.. Formation of Amphibole-Bearing Peridotite and Amphibole-Bearing Pyroxenite Through Hydrous Melt-Peridotite Reaction and In Situ Crystallization: An Experimental Study[J],2021,126(3).
APA	Wang C.,Liang Y.,&Xu W..(2021).Formation of Amphibole-Bearing Peridotite and Amphibole-Bearing Pyroxenite Through Hydrous Melt-Peridotite Reaction and In Situ Crystallization: An Experimental Study.Journal of Geophysical Research: Solid Earth,126(3).
MLA	Wang C.,et al."Formation of Amphibole-Bearing Peridotite and Amphibole-Bearing Pyroxenite Through Hydrous Melt-Peridotite Reaction and In Situ Crystallization: An Experimental Study".Journal of Geophysical Research: Solid Earth 126.3(2021).