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DOI	10.1016/j.gca.2021.07.010
	Deciphering a mantle degassing transect related with India-Asia continental convergence from the perspective of volatile origin and outgassing
	Zhang, Maoliang; Xu, Sheng; Zhou, Xiaocheng; Caracausi, Antonio; Sano, Yuji; Guo, Zhengfu; Zheng, Guodong; Lang, Yun-Chao; Liu, Cong-Qiang
通讯作者	Xu, S (通讯作者)，Tianjin Univ, Sch Earth Syst Sci, Inst Surface Earth Syst Sci, Tianjin 300072, Peoples R China. ; Zhou, XC (通讯作者)，China Earthquake Adm, Inst Earthquake Forecasting, Beijing 100036, Peoples R China.
发表日期	2021
ISSN	0016-7037
EISSN	1872-9533
起始页码	61
结束页码	78
卷号	310
英文摘要	Mantle degassing transect across different tectonic units within a plate convergent setting has been well documented for oceanic convergent margins by systematic changes in geochemistry (e.g., He-3/He-4, delta C-13, and CO2/He-3) of hydrothermal gases. However, little is known about spatial variations in volatile geochemistry across a continental convergent margin. In this study, we identify a mantle degassing transect in the southeastern Tibetan Plateau using He-CO2 systematics of hydrothermal gases, which extends from India-Asia continental convergent margin to intra-continent extensional region. delta C-13-CO2 (-11.8 parts per thousand to -3.1 parts per thousand) and CO2/He-3 (1.7 x 10(8) to 7.1 x 10(11)) values of hydrothermal gases show large variations that are consistent with modification by secondary physico-chemical processes, such as multi-component mixing, hydrothermal degassing, and calcite precipitation. Three levels of He degassing can be recognized based on He-3/He-4 dataset (0.01-5.87 RA) of the hydrothermal gas samples and their distances to volcanic centers. A magmatic level He degassing (35-74% mantle He) is found near active and/or Quaternary volcanoes fed by mantle-derived magmas. With increasing distance to volcanic centers, the outgassed magmatic volatiles are gradually diluted by crustal components (e.g., radiogenic He-4), defining a transitional level He degassing (13-33% mantle He). The He-3/He-4 values (8.16-8.48 (RA)) of olivine phenocrysts indicate a MORB (mid-ocean ridge basalts)-type mantle source for the magmatic and transitional levels of He degassing that are localized in Quaternary volcanic fields. In contrast, a background level He degassing (<12% mantle He) dominates the entire study area, and can be attributed to (i) degassing of sub-continental lithospheric mantle, and/or (ii) higher degrees of crustal contamination than those of the transitional level He degassing near volcanic centers. Combined with olivine He-3/He-4 data reported in this study and whole-rock Sr-87/Sr-86 data of host basalts from literature, source components of the mantle-derived magmas are suggested to include the MORB-type convective mantle, subducted Indian slab materials, and less degassed mantle materials, which can account for the possible decoupling between He and Sr isotope systematics. These findings delineate the origin and outgassing of mantle volatiles controlled by the India-Asia continental convergence, and would contribute to a better understanding of the deeply-sourced volatile emissions in these tectonic settings. (C) 2021 Elsevier Ltd. All rights reserved.
关键词	TENGCHONG VOLCANIC FIELD CARBON-ISOTOPE SYSTEMATICS REHAI GEOTHERMAL-FIELD YUNNAN PROVINCE MAGMA GENESIS SE TIBET GEOGRAPHICAL-DISTRIBUTION CRUSTAL STRUCTURE GAS GEOCHEMISTRY CO2 EMISSIONS
英文关键词	Mantle degassing; Geochemistry; Continental convergence; Quaternary volcanism; Neotectonic activity; Southeastern Tibetan Plateau
语种	英语
WOS研究方向	Geochemistry & Geophysics
WOS类目	Geochemistry & Geophysics
WOS记录号	WOS:000689517700005
来源期刊	GEOCHIMICA ET COSMOCHIMICA ACTA
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/255023
作者单位	[Zhang, Maoliang; Xu, Sheng; Sano, Yuji; Lang, Yun-Chao; Liu, Cong-Qiang] Tianjin Univ, Sch Earth Syst Sci, Inst Surface Earth Syst Sci, Tianjin 300072, Peoples R China; [Zhou, Xiaocheng] China Earthquake Adm, Inst Earthquake Forecasting, Beijing 100036, Peoples R China; [Caracausi, Antonio] Ist Nazl Geofis & Vulcanol, Sez Palermo, I-90146 Palermo, Italy; [Sano, Yuji] Univ Tokyo, Atmosphere & Ocean Res Inst, Kashiwa, Chiba 2778564, Japan; [Guo, Zhengfu] Chinese Acad Sci, Inst Geol & Geophys, Key Lab Cenozo Geol & Environm, Beijing 100029, Peoples R China; [Zheng, Guodong] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Lanzhou 730000, Peoples R China; [Sano, Yuji] Kochi Univ, Ctr Adv Marine Core Res, Kochi 7838502, Japan
推荐引用方式 GB/T 7714	Zhang, Maoliang,Xu, Sheng,Zhou, Xiaocheng,et al. Deciphering a mantle degassing transect related with India-Asia continental convergence from the perspective of volatile origin and outgassing[J]. 中国科学院西北生态环境资源研究院,2021,310.
APA	Zhang, Maoliang.,Xu, Sheng.,Zhou, Xiaocheng.,Caracausi, Antonio.,Sano, Yuji.,...&Liu, Cong-Qiang.(2021).Deciphering a mantle degassing transect related with India-Asia continental convergence from the perspective of volatile origin and outgassing.GEOCHIMICA ET COSMOCHIMICA ACTA,310.
MLA	Zhang, Maoliang,et al."Deciphering a mantle degassing transect related with India-Asia continental convergence from the perspective of volatile origin and outgassing".GEOCHIMICA ET COSMOCHIMICA ACTA 310(2021).