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DOI	10.1016/j.gr.2017.08.003
	Pamir Plateau formation and crustal thickening before the India-Asia collision inferred from dating and petrology of the 110-92 Ma Southern Pamir volcanic sequence
	Aminov, Jovid; Ding, Lin; Mamadjonov, Yunus; Dupont-Nivet, Guillaume; Aminov, Jamshed; Zhang, Li-Yun; Yoqubov, Shokirjon; Aminov, Javhar; Abdulov, Sherzod
通讯作者	Aminov, J (通讯作者)
发表日期	2017
ISSN	1342-937X
EISSN	1878-0571
起始页码	310
结束页码	326
卷号	51
英文摘要	The formation of the Pamir is a key component of the India-Asia collision with major implications for lithospheric processes, plateau formation, land-sea configurations and associated climate changes. Although the formation of the Pamir is traditionally linked to Cenozoic processes associated with the India-Asia collision, the contribution of the Mesozoic tectonic evolution remains poorly understood. The Pamir was formed by the suturing of Gondwanan terranes to the south margin of Eurasia, however, the timing and tectonic mechanisms associated with this Mesozoic accretion remain poorly constrained. These processes are recorded by several igneous belts within these terranes, which are not well studied. Within the Southern Pamir, the Albian-Turonian volcanic rocks and comagmatic plutons of the Kyzylrabat Igneous Complex (KIC) provide an important and still unconstrained record of the Pamir evolution. Here we provide the age, origin and the geodynamic setting of the KIC volcanics by studying their petrology, zircon U-Pb geochronology, geochemistry and isotope composition.17 samples from the KIC volcanics yield U-Pb ages spanning from 92 to 110 Ma. The volcanics are intermediate to acidic in composition (SiO2 = 56-69 wt%) and exhibit high-K calc-alkaline and shoshonitic affinity (K2O/Na2O = 12.2 wt%). They show enrichment in LILE and LREE and depletion in HFSE and HREE with negative Ta, Ti and Nb anomalies, suggesting an arc-related tectonic setting for their formation. Low sNd(t) values (from 9.1 to 4.7), relatively high Sr-87/Sr-86(i) ratios (0.7069-0.7096) and broad range of zircon stif values (from 22.6 to 1.5) suggest a mixture of different magma sources. These features suggest that volcanics were derived by crustal under- or intraplating of an enriched subduction-related mantle shoshonitic magmas, by heating and partial melting of the lower crust, and by mixing of both magma components. Our results further imply that the KIC volcanics represent a shoshonitic suite typical of an evolution from active continental arc to post-collisional setting with a steepening of the Benioff zone and thickening of the crust toward the back-arc. This setting is best explained by the subduction- collision transition along the Shyok suture due to accretion of the Kohistan island arc to the Karakoram. This suggests that a significant part of the crustal shortening and thickening accommodated in the Pamir occurred in the Mesozoic before the India-Asia collision with implications for regional tectonic models. This further suggests the Pamir was already a major topographic feature with potentially important paleoclimate forcing such as the monsoonal circulation. (C) 2017 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.
关键词	MIGMATITIC GNEISS DOME HINDU-KUSH CHEMICAL CLASSIFICATION ISOTOPIC CONSTRAINTS CALC-ALKALINE NW PAKISTAN SUTURE ZONE TIEN-SHAN EVOLUTION KARAKORAM
英文关键词	Southern Pamir; Cretaceous; Volcanic rocks; Geochemistry; Geochronology; Petrogenesis
语种	英语
WOS研究方向	Geology
WOS类目	Geosciences, Multidisciplinary
WOS记录号	WOS:000416499300019
来源期刊	GONDWANA RESEARCH
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/259094
推荐引用方式 GB/T 7714	Aminov, Jovid,Ding, Lin,Mamadjonov, Yunus,et al. Pamir Plateau formation and crustal thickening before the India-Asia collision inferred from dating and petrology of the 110-92 Ma Southern Pamir volcanic sequence[J]. 中国科学院青藏高原研究所,2017,51.
APA	Aminov, Jovid.,Ding, Lin.,Mamadjonov, Yunus.,Dupont-Nivet, Guillaume.,Aminov, Jamshed.,...&Abdulov, Sherzod.(2017).Pamir Plateau formation and crustal thickening before the India-Asia collision inferred from dating and petrology of the 110-92 Ma Southern Pamir volcanic sequence.GONDWANA RESEARCH,51.
MLA	Aminov, Jovid,et al."Pamir Plateau formation and crustal thickening before the India-Asia collision inferred from dating and petrology of the 110-92 Ma Southern Pamir volcanic sequence".GONDWANA RESEARCH 51(2017).