气候变化领域集成服务门户(CCPortal): Disclosing the most intense magmatic flare-up in southern Tibet: Insights from study of the Pangduo volcanic-plutonic complex

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DOI	10.1016/j.lithos.2023.107267
	Disclosing the most intense magmatic flare-up in southern Tibet: Insights from study of the Pangduo volcanic-plutonic complex
	Chen, Hou-Bin; Ji, Wei-Qiang; Zhang, Shao-Hua; Jiang, Hehe; Xu, Qiang
发表日期	2023
ISSN	0024-4937
EISSN	1872-6143
卷号	454
英文摘要	The Gangdese arc underwent the most intense magmatic flare-up of southern Tibet in the early Eocene (peaked at similar to 50 Ma), generating widespread plutonic and volcanic rocks both along and across the arc. However, the dynamic mechanism for the magmatic flare-up is mysterious. This paper systematically analyzed the petrology, mineralogy, geochronology, and geochemistry of the early Eocene volcanic and intrusive rocks in the Pangduo basin in the eastern Gangdese arc. These rocks yielded identical zircon U-Pb ages of similar to 50 Ma and similar isotopic compositions. The low-silica (< 60 wt%) rocks, including basalt andesite and trachyandesite, result from low degree (2-3%) partial melting of garnet-bearing lithospheric mantle. Based on textural observations and geochemical studies, coupled with Rhyolite-MELTS modeling and zircon trace elements Rayleigh fractionation models, the following research results were obtained. The high-silica rhyolite, ignimbrite, and granite porphyry are the product of limited melt extraction, while the quartz monzonite belongs to the associated residual silicic cumulates. The quartz monzonitic porphyry and trachydacite show a widespread dissolution structure and high formation temperature of similar to 850 degrees C. Whole-rock geochemical mixing model results indicate that they are generated by mixing products of mafic magma, high-silica melts, and remelting melts of quartz monzonite. The volcanic and intrusive rocks in the Pangduo basin are considered as a volcanic-plutonic complex, resulting from the synergistic effect of melt extraction and cognate magma mixing. Both the complex magmatic processes and the early Eocene magmatic flare-up are attributed to mafic magma injection.
关键词	Gangdese arc Southern Tibet Pangduo volcanic -plutonic complex Magmatic process Flare-up
英文关键词	ISOTOPIC CONSTRAINTS; GANGDESE BATHOLITH; NEOTETHYAN SLAB; PB AGE; ROCKS; GEOCHEMISTRY; RESERVOIRS; BASALTS; ORIGIN; GROWTH
WOS研究方向	Geochemistry & Geophysics ; Mineralogy
WOS记录号	WOS:001062455300001
来源期刊	LITHOS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/282872
作者单位	Chinese Academy of Sciences; Institute of Geology & Geophysics, CAS; Chinese Academy of Sciences; University of Chinese Academy of Sciences, CAS
推荐引用方式 GB/T 7714	Chen, Hou-Bin,Ji, Wei-Qiang,Zhang, Shao-Hua,et al. Disclosing the most intense magmatic flare-up in southern Tibet: Insights from study of the Pangduo volcanic-plutonic complex[J],2023,454.
APA	Chen, Hou-Bin,Ji, Wei-Qiang,Zhang, Shao-Hua,Jiang, Hehe,&Xu, Qiang.(2023).Disclosing the most intense magmatic flare-up in southern Tibet: Insights from study of the Pangduo volcanic-plutonic complex.LITHOS,454.
MLA	Chen, Hou-Bin,et al."Disclosing the most intense magmatic flare-up in southern Tibet: Insights from study of the Pangduo volcanic-plutonic complex".LITHOS 454(2023).