气候变化领域集成服务门户(CCPortal): Secular evolution of the lithospheric mantle beneath the northern margin of the North China Craton: Insights from zoned olivine xenocrysts in Early Cretaceous basalts

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DOI	10.1130/B35443.1
	Secular evolution of the lithospheric mantle beneath the northern margin of the North China Craton: Insights from zoned olivine xenocrysts in Early Cretaceous basalts
	Xu Y.; Zhang H.
发表日期	2020
ISSN	167606
起始页码	2353
结束页码	2366
卷号	132 期号:2021-11-12
英文摘要	Abundant zoned olivine xenocrysts from Early Cretaceous basalts of the Yixian Formation in western Liaoning Province, China, contain critical information about the nature and evolution of the lithospheric mantle of the northern North China Craton. These olivine xenocrysts are large (600–1600 μm), usually rounded and embayed, with well-developed cracks. Their cores have high and uniform forsterite (Fo) contents (88–91), similar to the peridotitic olivine entrained by regional Cenozoic basalts. Their rims have much lower Fo contents (74–82), comparable to phenocrysts (72–81) in the host basalts. These characteristics reveal that the zoned olivine has been disaggregated from mantle xenoliths and thus can be used to trace the underlying lithospheric mantle at the time of basaltic magmatism. The olivine cores have high oxygen isotope compositions (δ18OSMOW = 5.9–7.0‰) relative to the normal mantle value, suggesting that the Early Cretaceous lithospheric mantle was enriched and metasomatized mainly by melts/fluids released from subducted oceanic crust that had experienced low-temperature hydrothermal alteration. Preservation of zoned olivine xenocrysts in the Early Cretaceous basalts indicates that olivine-melt/fluid reaction could have been prevalent in the lithospheric mantle as an important mechanism for the transformation from old refractory (high-Mg) peridotitic mantle to young, fertile (low-Mg), and enriched lithospheric mantle during the early Mesozoic. © 2020 Geological Society of America. All Rights Reserved.
语种	英语
来源期刊	Bulletin of the Geological Society of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/184839
作者单位	State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi'an, 710069, China; State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, P.O. Box 9825, Beijing, 100029, China
推荐引用方式 GB/T 7714	Xu Y.,Zhang H.. Secular evolution of the lithospheric mantle beneath the northern margin of the North China Craton: Insights from zoned olivine xenocrysts in Early Cretaceous basalts[J],2020,132(2021-11-12).
APA	Xu Y.,&Zhang H..(2020).Secular evolution of the lithospheric mantle beneath the northern margin of the North China Craton: Insights from zoned olivine xenocrysts in Early Cretaceous basalts.Bulletin of the Geological Society of America,132(2021-11-12).
MLA	Xu Y.,et al."Secular evolution of the lithospheric mantle beneath the northern margin of the North China Craton: Insights from zoned olivine xenocrysts in Early Cretaceous basalts".Bulletin of the Geological Society of America 132.2021-11-12(2020).