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DOI	10.1002/gj.4268
	Geochemical and geochronological studies of Abor volcanic rocks of eastern Himalaya
	Baral, Upendra; Ding, Lin; Goswami, Tapos Kumar; Sarma, Mondip; Jan, M. Q.; Wang, Chao; Aminov, Jovid; Qasim, Muhammad; Bezbaruah, Devojit
通讯作者	Ding, L (通讯作者)
发表日期	2022
ISSN	0072-1050
EISSN	1099-1034
起始页码	482
结束页码	502
卷号	57 期号:2
英文摘要	The Indian Plate began drifting northward after the Gondwana breakup and collided with the Eurasian Plate during the Early Cenozoic, resulting in the consequential development of the Himalayan-Tibetan Orogeny. Several microcontinents were rifted from Gondwana and amalgamated with the Indian Plate, resulting in magmatism along the continental margin. The Abor volcanic rocks (AVRs) in the eastern Himalaya represent one of such magmatism, the emplacement mechanism, and the timing of which is still a topic of debate. The AVR comprises mafic and silicic rocks; the present study concerns the petrography and geochemistry of the mafic rocks. U-Pb geochronology on three samples shows the weighted mean age of 130 +/- 1 Ma, 143 +/- 1.2 Ma, and 155 +/- 16 Ma. Whole-rock geochemistry of eight samples shows Mg# of 45.48 to 57.7, except for one sample with 37.4, variable contents of CaO (4.4-9.5 wt%), K2O (0.1-2.6%), Lost on ignition (LOI) (0.9-3.6 wt%; average 2.4), and K2O/Na2O ratios (0.02-0.6 with a single one 1.0), Y/Nb (0.55-1.66, with one value of 2.44), and medium to high Zr/Nb (10.1-14.1) and Zr/Y (5.4-18.14). The Sr-isotopic results from 11 samples show that the initial Sr-87/Sr-86 ratios vary between 0.7049 and 0.7110, and epsilon(Nd)(t) values range from +1.176 to -2.250. Geochemical and isotopic data suggest that the studied AVRs (mafic) are of subalkaline tholeiitic affinity. These volcanic rocks have continental intraplate characteristics and are sourced from the metasomatized mantle during the rifting event of the Indian subcontinent from Gondwana during Late Jurassic to Early Cretaceous.
关键词	LARGE IGNEOUS PROVINCE HIGH-TI BASALTS U-PB TRACE-ELEMENT TIBET IMPLICATIONS MANTLE SOURCES SIANG WINDOW INDIAN PLATE ARC ROCKS LU-HF
英文关键词	Abor volcanic rocks; eastern Himalaya; Gondwana rift; Indian subcontinent; Siang Valley
语种	英语
WOS研究方向	Geology
WOS类目	Geosciences, Multidisciplinary
WOS记录号	WOS:000697307700001
来源期刊	GEOLOGICAL JOURNAL
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/260732
推荐引用方式 GB/T 7714	Baral, Upendra,Ding, Lin,Goswami, Tapos Kumar,et al. Geochemical and geochronological studies of Abor volcanic rocks of eastern Himalaya[J]. 中国科学院青藏高原研究所,2022,57(2).
APA	Baral, Upendra.,Ding, Lin.,Goswami, Tapos Kumar.,Sarma, Mondip.,Jan, M. Q..,...&Bezbaruah, Devojit.(2022).Geochemical and geochronological studies of Abor volcanic rocks of eastern Himalaya.GEOLOGICAL JOURNAL,57(2).
MLA	Baral, Upendra,et al."Geochemical and geochronological studies of Abor volcanic rocks of eastern Himalaya".GEOLOGICAL JOURNAL 57.2(2022).