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DOI	10.1016/j.lithos.2024.107549
	Identification of Indian crustal melting beneath Gangdese arc during India-Asia collision
	He, Shao-Xiong; Liu, Xiao-Chi; Hu, Fangyang; Wang, Jia-Min; Ji, Wei-Qiang
发表日期	2024
ISSN	0024-4937
EISSN	1872-6143
起始页码	470-471
卷号	470-471
英文摘要	The continental collision between the Indian and Asian plates constitutes one of the most distinguished convergent systems on a global scale. Geophysical data have revealed that subducted Indian slab lies beneath the Lhasa terrane of the Asian plate. However, whether, when, and how the Indian continental crust contributed to the magmatism in the Lhasa terrane remain unclear. In this study, we present petrological, geochronological, and geochemical evidence for Indian crustal melting beneath the Lhasa terrane in the Ayilari range (western Gangdese). Zircon and monazite U-(Th)-Pb dating and whole -rock Sr-Nd-Hf isotope analysis show that the Ayilari granitoids can be divided into three stages: (i) Paleocene -Eocene granites (60-45 Ma) with juvenile isotopic compositions (87Sr/86Sr(t) = 0.706474-0.709635, epsilon Nd(t) = +0.3 to +1.0, epsilon Hf(t) = +7.2 to +8.1); (ii) Oligocene -early Miocene granites (29-21 Ma) with slightly evolved isotopic compositions (87Sr/86Sr(t) = 0.707809-0.719349, epsilon Nd(t) = -11.2 to -6.7, epsilon Hf(t) = -4.8 to -1.5); and (iii) Miocene leucogranites and porphyritic granites (18-12 Ma) with isotopic compositions that show clear signature of evolved crustal material (87Sr/86Sr(t) = 0.725465-0.745704, epsilon Nd(t) = -15.2 to -12.0, epsilon Hf(t) = -13.7 to -11.3). Comparing our findings with existing data on the Himalayan leucogranites and intermediate-silicic rocks in southern Lhasa, we find that the Miocene leucogranites and porphyritic granites align with the characteristics of the Himalayan leucogranites, but differ from the southern Lhasa rocks. Furthermore, the elevated whole -rock beryllium concentrations and the absence of a zircon age peak around 1170 Ma in the inherited zircons imply the incorporation of Indian crustal material into the magma source of the Oligocene -early Miocene granites. Isotopic data for the Miocene granites also indicate that these rocks were derived from the Indian continental crust. We posit that the newly identified Oligocene and Miocene granites record the Indian crustal melting beneath the Lhasa terrane. Integration of Ayilari geologic data with orogen-scale magmatic and tectonic data suggests that changes of subduction geometry and periodic underthrusting of the Indian continental slab perhaps explain the alter of magmatic sources.
英文关键词	Continental collision; Continental refinement; Himalayan orogen; Indian crust; Ayilari range
语种	英语
WOS研究方向	Geochemistry & Geophysics ; Mineralogy
WOS类目	Geochemistry & Geophysics ; Mineralogy
WOS记录号	WOS:001199112900001
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/292310
作者单位	Chinese Academy of Sciences; Institute of Geology & Geophysics, CAS; Chinese Academy of Sciences; University of Chinese Academy of Sciences, CAS; Queens University - Canada; Chinese Academy of Sciences; Institute of Geology & Geophysics, CAS
推荐引用方式 GB/T 7714	He, Shao-Xiong,Liu, Xiao-Chi,Hu, Fangyang,et al. Identification of Indian crustal melting beneath Gangdese arc during India-Asia collision[J],2024,470-471.
APA	He, Shao-Xiong,Liu, Xiao-Chi,Hu, Fangyang,Wang, Jia-Min,&Ji, Wei-Qiang.(2024).Identification of Indian crustal melting beneath Gangdese arc during India-Asia collision.LITHOS,470-471.
MLA	He, Shao-Xiong,et al."Identification of Indian crustal melting beneath Gangdese arc during India-Asia collision".LITHOS 470-471(2024).