气候变化领域集成服务门户(CCPortal): Extremely enriched lithospheric mantle-derived magmas in the central Lhasa Terrane, southern Tibet

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DOI	10.1080/00206814.2023.2297416
	Extremely enriched lithospheric mantle-derived magmas in the central Lhasa Terrane, southern Tibet
	Zhang, Yutong; Huang, Feng; Xu, Jifeng; Liu, Han; Li, Mingjian; Zeng, Yunchuan; Hu, Jing; Lv, Mingda; Liu, Xijun
发表日期	2024
ISSN	0020-6814
EISSN	1938-2839
起始页码	971
结束页码	991
卷号	66 期号:4
英文摘要	Plate tectonics plays a crucial role in the evolution of Earth's continents and oceans. However, the impact of oceanic subduction and continental collision on the continental lithospheric mantle within collisional orogenic belts is still a matter of debate. To address this issue, we performed a thorough analysis of mafic rocks in the Nixiong area within the central Lhasa Terrane, southern Tibet. The mafic rocks are composed of diabases and basalts formed during syn-collisional period (similar to 50 Ma). The diabases have low SiO2 and moderate MgO contents, and are enriched in large ion lithophile elements and depleted in high field strength elements. They show high Sr-87/Sr-86(i) (0.711451-0.712084) and low epsilon(Nd)(t) (-7.9 to -6.44), as well as enriched Hf-Pb isotope compositions (epsilon(Hf)(t) = -7.58 to -6.59; Pb-206/Pb-204(i) = 18.59-18.71; Pb-207/Pb-204(i) = 15.71-15.72; Pb-208/Pb-204(i) = 39.33-39.53). Geochemical modelling suggests that the diabases were formed through the partial melting of peridotite at high temperatures and shallow depths, with significant addition of subduction-related components to the primary melts. The diabases probably originated from a metasomatized lithospheric mantle due to subduction of Neo-Tethyan slab. The basalts display similar SiO2 but lower MgO contents compare with the diabases. They are also characterized by extremely high Sr-87/Sr-86(i) (0.713332-0.713448), low epsilon(Nd)(t) (-10.32 to -9.96), and significantly enriched Hf-Pb isotope compositions (epsilon(Hf)(t) = -12.30 to -12.05; Pb-206/Pb-204(i) = 18.81-18.85; Pb-207/Pb-204(i) = 15.74-15.75; Pb-208/Pb-204(i) = 39.81-39.88), corresponding to an extremely enriched lithospheric mantle. Integrated with the previous studies, the Nixiong mafic rocks exhibit the most enriched isotopic compositions among the arc- or syn-collision-related mafic rocks in southern Tibet. These extremely isotopically enriched components were most likely derived from the ancient continental lithospheric mantle beneath the central Lhasa Terrane. Our results provided unambiguous evidence that the pre-existing ancient continental lithospheric mantle could persist locally during the prolonged oceanic subduction and subsequent continental collision. [GRAPHICS] .
关键词	Mafic rocks lithospheric mantle syn-collision magmatism central Lhasa Terrane Tibetan Plateau
WOS研究方向	Geology
WOS记录号	WOS:001137497700003
来源期刊	INTERNATIONAL GEOLOGY REVIEW
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/283056
作者单位	China University of Geosciences - Beijing; China University of Geosciences - Beijing; Guilin University of Technology; China Geological Survey; Chinese Academy of Sciences; Guiyang Institute of Geochemistry, CAS; Michigan State University
推荐引用方式 GB/T 7714	Zhang, Yutong,Huang, Feng,Xu, Jifeng,et al. Extremely enriched lithospheric mantle-derived magmas in the central Lhasa Terrane, southern Tibet[J],2024,66(4).
APA	Zhang, Yutong.,Huang, Feng.,Xu, Jifeng.,Liu, Han.,Li, Mingjian.,...&Liu, Xijun.(2024).Extremely enriched lithospheric mantle-derived magmas in the central Lhasa Terrane, southern Tibet.INTERNATIONAL GEOLOGY REVIEW,66(4).
MLA	Zhang, Yutong,et al."Extremely enriched lithospheric mantle-derived magmas in the central Lhasa Terrane, southern Tibet".INTERNATIONAL GEOLOGY REVIEW 66.4(2024).