气候变化领域集成服务门户(CCPortal): Mantle-Derived Helium Distribution and Tectonic Implications in the Sichuan-Yunnan Block, China

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DOI	10.1021/acsomega.1c04533
	Mantle-Derived Helium Distribution and Tectonic Implications in the Sichuan-Yunnan Block, China
	Meng, Bingkun; Zhou, Shixin; Li, Jing; Sun, Zexiang
通讯作者	Zhou, SX ; Li, J (通讯作者)，Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Lanzhou 730000, Peoples R China. ; Zhou, SX ; Li, J (通讯作者)，Key Lab Petr Resources, Lanzhou 730000, Gansu, Peoples R China.
发表日期	2021
ISSN	2470-1343
起始页码	30674
结束页码	30685
卷号	6 期号:45
英文摘要	The geochemical characteristics of mantle degassing observed on the surface of the earth can indicate the origin and migration path of mantle fluids. Compared with the plate boundary tectonic environment, the intraplate tectonic environment does not have a large number of active volcanoes and active faults, and the observation of mantle volatiles in hot spring gas is relatively limited. We selected the Sichuan-Yunnan block to discuss mantle degassing based on the carbon and noble gas isotopes of the spring gases and previous studies on the fault slip rate and geophysical research. A total of five hot spring gas samples (including two free gases and three dissolved gases) were collected from the Sichuan-Yunnan block. Chemical and isotopic compositions were analyzed in N-2-dominant hot spring gases. The He-3/He-4 ratio (0.068-0.541 R-a) indicates the occurrence of mantle-derived helium throughout the Sichuan-Yunnan block, which has been diluted by a crustal radiogenic He-4 component. The occurrence of mantle-derived helium in the study areas ranges from 0.74 to 5.67%. The lower proportion of mantle-derived helium in YNWQ and HGWQ than that in other spring gases near the Jinghe-Qinghe fault may be caused by the smaller scale of fault around YNWQ and HGWQ than the Jinghe-Qinghe fault. The correlation between He-4, Ne-20, and N-2 concentrations implies a common trapping mechanism for He-4, Ne-20, and N-2 in hot spring gases. The Ar-40/Ar-36 ratios and N-2/Ar ratios indicate that N-2 and Ar are mostly meteoric, and YNWQ and HGWQ have more crustal-derived Ar contribution (40.56 and 51.49%, respectively). The delta C-13(CO2)(o) values calculated by Rayleigh fractionation and CO2 concentration suggest that CO2 has inorganic and organic origins. The plot of R-c/R-a versus delta C-13(CO2) indicates that the spring gas CO2 origin in the Sichuan-Yunnan block is mainly derived from mixing of limestone and organic sediments with minor mantle CO2. The delta C-13(CH4) versus CH4/He-3 values indicate that the origin of methane is thermogenic and microbial oxidation. The low mantle-derived helium distribution pattern is most likely controlled by the weak fault activity rate, the small fault scale, and not obvious magmatic activity in the Sichuan-Yunnan block.
关键词	CARBON ISOTOPIC COMPOSITIONS TENGCHONG VOLCANIC FIELD SAN-ANDREAS FAULT NOBLE-GASES VOLATILE FLUXES NEON ISOTOPES SPRING GASES BASIN CO2 ORIGIN
语种	英语
WOS研究方向	Chemistry
WOS类目	Chemistry, Multidisciplinary
WOS记录号	WOS:000721114500042
来源期刊	ACS OMEGA
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/253947
作者单位	[Meng, Bingkun; Zhou, Shixin; Li, Jing; Sun, Zexiang] Chinese Acad Sci, Northwest Inst Ecoenvironm & Resources, Lanzhou 730000, Peoples R China; [Meng, Bingkun; Zhou, Shixin; Li, Jing; Sun, Zexiang] Key Lab Petr Resources, Lanzhou 730000, Gansu, Peoples R China; [Meng, Bingkun; Sun, Zexiang] Univ Chinese Acad Sci, Beijing 100049, Peoples R China
推荐引用方式 GB/T 7714	Meng, Bingkun,Zhou, Shixin,Li, Jing,et al. Mantle-Derived Helium Distribution and Tectonic Implications in the Sichuan-Yunnan Block, China[J]. 中国科学院西北生态环境资源研究院,2021,6(45).
APA	Meng, Bingkun,Zhou, Shixin,Li, Jing,&Sun, Zexiang.(2021).Mantle-Derived Helium Distribution and Tectonic Implications in the Sichuan-Yunnan Block, China.ACS OMEGA,6(45).
MLA	Meng, Bingkun,et al."Mantle-Derived Helium Distribution and Tectonic Implications in the Sichuan-Yunnan Block, China".ACS OMEGA 6.45(2021).