气候变化领域集成服务门户(CCPortal): Subduction of Indian continental lithosphere constrained by Eocene-Oligocene magmatism in northern Myanmar

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DOI	10.1016/j.lithos.2019.105211
	Subduction of Indian continental lithosphere constrained by Eocene-Oligocene magmatism in northern Myanmar
	Li, Jin-Xiang; Fan, Wei-Ming; Zhang, Li-Yun; Ding, Lin; Sun, Ya-Li; Peng, Tou-Ping; Cai, Fu-Long; Guan, Qiu-Yun; Sein, Kyaing
通讯作者	Li, JX (通讯作者)
发表日期	2019
ISSN	0024-4937
EISSN	1872-6143
卷号	348
英文摘要	Subduction of the Indian continental lithosphere in the eastern Tibet-Himalaya orogenic belt remains unclear. Newly reported zircon U-Pb ages in this study indicate that the Shangalon intermediate-felsic magmatic rocks in northern Myanmar formed at Eocene-Oligocene (similar to 40-32 Ma). They have calc-alkaline to shoshonitic characteristics, LREE-enriched patterns, enrichments in LILE (e.g., Rb, Cs), and depletions in HFSE (e.g., Nb). Obviously, they show the higher initial Sr and lower Nd-Hf isotopic compositions (Sr-87/Sr-86(i) = 0.7054-0.7082, epsilon Nd(t) =-5.3 to-0.4, and epsilon Hf(t) =-3.4 to 10.8) than Cretaceous arc-related mafic-felsic rocks in the West Burma terrane. A positive correlation between Nd isotopic compositions and SiO2 contents indicates that the Eocene Shangalon diorite and andesite with the lowest epsilon Nd(t) values (-5.3 to -4.0) likely derived from a mantle source contaminated by the subducted Indian continental lithosphere. Coupled with regional coeval OIB-like mafic melts and high temperature metamorphism, the Eocene-Oligocene Shangalon magma might have formed in the Neo-Tethyan oceanic slab break-off setting after the India-Asia collision. In addition, Eocene granodioritic rocks have the adakitic features, which possibly resulted by fractional crystallization of hornblende. The hornblende-dominated crystallization in the Shangalon ore-bearing granodioritic rocks is well consistent with magma evolution of H2O-rich melts, which play an important role in the formation of the Eocene Shangalon porphyry Cu-Au deposit. (C) 2019 Elsevier B.V. All rights reserved.
关键词	ZIRCON U-PB SOUTHERN TIBET EVIDENCE PORPHYRY CU DEPOSITS TECTONIC EVOLUTION DOMINATED FRACTIONATION ISOTOPIC CONSTRAINTS CENOZOIC VOLCANISM EURASIA COLLISION NEOTETHYAN SLAB OROGENIC BELT
英文关键词	Continental lithosphere subduction; Break-off; Eocene-Oligocene; Adakitic magmatism; Myanmar
语种	英语
WOS研究方向	Geochemistry & Geophysics ; Mineralogy
WOS类目	Geochemistry & Geophysics ; Mineralogy
WOS记录号	WOS:000500375700022
来源期刊	LITHOS
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/259496
推荐引用方式 GB/T 7714	Li, Jin-Xiang,Fan, Wei-Ming,Zhang, Li-Yun,et al. Subduction of Indian continental lithosphere constrained by Eocene-Oligocene magmatism in northern Myanmar[J]. 中国科学院青藏高原研究所,2019,348.
APA	Li, Jin-Xiang.,Fan, Wei-Ming.,Zhang, Li-Yun.,Ding, Lin.,Sun, Ya-Li.,...&Sein, Kyaing.(2019).Subduction of Indian continental lithosphere constrained by Eocene-Oligocene magmatism in northern Myanmar.LITHOS,348.
MLA	Li, Jin-Xiang,et al."Subduction of Indian continental lithosphere constrained by Eocene-Oligocene magmatism in northern Myanmar".LITHOS 348(2019).