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DOI	10.1016/j.jseaes.2022.105539
	Origin and tectonic implications of Paleocene high-Mg dioritic plutons in the Lhasa terrane, Qulong area, Tibet
	Du, Qiuding; Qin, Zhipeng; Zhang, Gangyang; Wang, Jian; Zhou, Gang; He, Yuan
发表日期	2023
ISSN	1367-9120
EISSN	1878-5786
卷号	246
英文摘要	Zircon U-Pb ages, geochemical data, and Sr-Nd-Hf isotopic data are reported for the Paleocene Qulong high-Mg dioritic plutons (HMDPs) in southern Tibet of the India-Asia collision zone to investigate their source, petro- genesis, and tectonic setting. The Qulong HMDPs consist of diorite with a 206Pb/238U age of 63.45 +/- 0.87 Ma and gabbro-diorite with a 206Pb/238U age of 63.8 +/- 0.57 Ma. They are metaluminous calc-alkaline rocks and exhibit sanukitic HMD affinity with moderate SiO2 and TiO2 and high MgO (5.24-8.64 wt%) and Mg# (55.78-65.89). They exhibit large ion lithophile element and light rare earth element enrichment and Nb-Ta depletion, rela- tively low (Th/Nb)N ratios, and high (La/Sm)N , La/Ta, and La/Nb ratios, which are similar to oceanic island basalts derived from the subduction-related mantle source. In addition, relatively low initial 87Sr/86Sr ratios (0.7056-0.7062), positive epsilon Nd(t) (+2.23 to + 3.34), and epsilon Hf(t) (+4.55 to + 12.35) indicate the origin of the Qulong HMDPs to be the subduction-related lithospheric mantle which had been modified by the asthenosphere, and mixed with the sediment melt. This study suggests that the Qulong HMDPs are a product of the upwelling of the asthenosphere triggered by the slab roll-back of the subducting NeoTethys slab of the India-Asia collision at ca. 64 Ma.
关键词	High-Mg dioritic plutons Roll-back Tibet Asthenosphere Early Paleocene
英文关键词	SETOUCHI VOLCANIC BELT; U-PB AGE; CONTINENTAL-CRUST; SOUTHERN TIBET; IGNEOUS ROCKS; ISOTOPIC CONSTRAINTS; MAGNESIAN ANDESITES; SOUTHWEST JAPAN; ADAKITIC ROCKS; WESTERN MARGIN
WOS研究方向	Geosciences, Multidisciplinary
WOS记录号	WOS:000947957400001
来源期刊	JOURNAL OF ASIAN EARTH SCIENCES
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/282603
作者单位	Southwest Petroleum University; Southwest Petroleum University; Southwest Petroleum University; Chengdu University of Technology; Sinopec; China National Petroleum Corporation
推荐引用方式 GB/T 7714	Du, Qiuding,Qin, Zhipeng,Zhang, Gangyang,et al. Origin and tectonic implications of Paleocene high-Mg dioritic plutons in the Lhasa terrane, Qulong area, Tibet[J],2023,246.
APA	Du, Qiuding,Qin, Zhipeng,Zhang, Gangyang,Wang, Jian,Zhou, Gang,&He, Yuan.(2023).Origin and tectonic implications of Paleocene high-Mg dioritic plutons in the Lhasa terrane, Qulong area, Tibet.JOURNAL OF ASIAN EARTH SCIENCES,246.
MLA	Du, Qiuding,et al."Origin and tectonic implications of Paleocene high-Mg dioritic plutons in the Lhasa terrane, Qulong area, Tibet".JOURNAL OF ASIAN EARTH SCIENCES 246(2023).