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DOI	10.1080/00206814.2022.2042744
	Binary mixing of lithospheric mantle and asthenosphere beneath Tengchong volcano, SE Tibet: evidence from noble gas isotopic signatures
	Chen, Kefei; He, Huaiyu; Stuart, Finlay; Liu, Shaolin; Xu, Xiwei; Cheng, Zhihui; Yang, Dinghui; Li, Jiyong; Su, Fei; Wang, Wenshuai
通讯作者	Liu, SL (通讯作者)，Minist Emergency Management China, Natl Inst Nat Hazards, Beijing, Peoples R China.
发表日期	2020
ISSN	0020-6814
EISSN	1938-2839
英文摘要	The Miocene-Quaternary Tengchong volcanic field in SE Tibet was generated after the main stage of continental collision between India and Eurasia. Consensus on the origin of Tengchong volcanism has not yet been achieved. In this study, we analysed the He-Ar isotopic compositions of olivine and pyroxene phenocrysts, whole-rock major and trace elements and Sr-Nd-Pb isotopic compositions. The He-3/He-4 ratios range from 4.1 to 8.2 Ra (Ra = 1.4 x 10(-6)), overlapping the values of mid-ocean ridge basalt (7.0-9.0 Ra) and subcontinental lithospheric mantle (SCLM, 5.2-7.0 Ra). The low He-3/He-4 (< 7.0 Ra) basalts have high Sr-87/Sr-86 (average of 0.707928) and La/Yb (average of 22.0) ratios and low Nb/La (average of 0.36) ratios, whereas the high He-3/He-4 (> 7.0 Ra) basalts exhibit relatively low Sr-87/Sr-86 (average of 0.706708) and La/Yb (average of 17.0) ratios and relatively high Nb/La (average of 0.52) ratios. These observations indicate that the primitive magmas originated from a mixture of metasomatized SCLM and enriched asthenospheric mantle. The SCLM was likely metasomatized by the subducted Neo-Tethyan oceanic plate, while the asthenospheric mantle was enriched by the subducting Indian oceanic plate. The increasing trend of He-3/He-4 ratios and decreasing trend of Sr-87/Sr-86 ratios over time suggest that the contribution of the metasomatized SCLM decreased after the late Pleistocene relative to that of the enriched asthenosphere, reflecting progressive lithospheric extension and thinning. Our results reveal that magmatic He isotopes can be used to constrain deep dynamic processes. [GRAPHICS] .
关键词	WESTERN YUNNAN TRACE-ELEMENT GEOCHEMICAL EVIDENCE MIDOCEAN RIDGE ROCKS HELIUM CHINA CONSTRAINTS SUBDUCTION ORIGIN
英文关键词	Intraplate volcano; tengchong; helium isotope; trace element; SCLM
语种	英语
WOS研究方向	Geology
WOS类目	Geology
WOS记录号	WOS:000760758100001
来源期刊	INTERNATIONAL GEOLOGY REVIEW
来源机构	中国科学院西北生态环境资源研究院
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/255152
作者单位	[Chen, Kefei; Liu, Shaolin; Xu, Xiwei] Minist Emergency Management China, Natl Inst Nat Hazards, Beijing, Peoples R China; [Chen, Kefei] Chinese Acad Sci, Inst Geol & Geophys, State Key Lab Lithospher Evolut, Beijing, Peoples R China; [He, Huaiyu; Su, Fei] Chinese Acad Sci, Inst Geol & Geophys, Cas Key Lab Earths Deep Interior, Beijing, Peoples R China; [Stuart, Finlay] Scottish Univ Environm Res Ctr, Isotope Geosci Unit, E Kilbride, Lanark, Scotland; [Cheng, Zhihui] Lingnan Normal Univ, Sch Geog Sci, Zhanjiang, Peoples R China; [Yang, Dinghui] Tsinghua Univ, Dept Math Sci, Beijing, Peoples R China; [Li, Jiyong] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Key Lab Petr Resources Res, Lanzhou, Gansu, Peoples R China; [Wang, Wenshuai] Ningxia Univ, Sch Math & Stat, Yinchuan, Ningxia, Peoples R China
推荐引用方式 GB/T 7714	Chen, Kefei,He, Huaiyu,Stuart, Finlay,et al. Binary mixing of lithospheric mantle and asthenosphere beneath Tengchong volcano, SE Tibet: evidence from noble gas isotopic signatures[J]. 中国科学院西北生态环境资源研究院,2020.
APA	Chen, Kefei.,He, Huaiyu.,Stuart, Finlay.,Liu, Shaolin.,Xu, Xiwei.,...&Wang, Wenshuai.(2020).Binary mixing of lithospheric mantle and asthenosphere beneath Tengchong volcano, SE Tibet: evidence from noble gas isotopic signatures.INTERNATIONAL GEOLOGY REVIEW.
MLA	Chen, Kefei,et al."Binary mixing of lithospheric mantle and asthenosphere beneath Tengchong volcano, SE Tibet: evidence from noble gas isotopic signatures".INTERNATIONAL GEOLOGY REVIEW (2020).