| Slab break-off triggered lithosphere - asthenosphere interaction at a convergent margin: The Neoproterozoic bimodal magmatism in NW India |
| Wei Wang; Manoj K. Pandit; Jun-Hong Zhao; Wei-Terry Chen; Jian-Ping Zheng
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| 2018
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发表期刊 | Lithos
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卷号 | 296页码:281-296 |
摘要 |
The Neoproterozoic Malani Igneous Suite (MIS) is described as the largest felsic igneous province in India. The linearly distributed Sindreth and Punagarh basins located along eastern margin of this province represent the only site of bimodal volcanism and associated clastic sediments within the MIS. The in-situ zircon U-Pb dating by LA-ICPMS reveals that the Sindreth rhyolites were erupted at 769-762 Ma. Basaltic rocks from both the basins show distinct geochemical signatures that suggest an E-MORB source for Punagarh basalts (low Ti/V ratios of 40.9-28.2) and an OIB source (high Ti/V ratios of 285-47.6) for Sindreth basalts. In the absence of any evidence of notable crustal contamination, these features indicate heterogeneous mantle sources for them. The low (La/Yb)(CN) (9.34-2.10) and Sm/Yb (2.88-1.08) ratios of Punagarh basalts suggest a spinel facies, relatively shallow level mantle source as compared to a deeper source for Sindreth basalts, as suggested by high (La/Yb)(CN) (7.24-5.24) and Sm/Yb (2.79-2.13) ratios. Decompression melting of an upwelling sub-slab asthenosphere through slab window seems to be the most plausible mechanism to explain the geochemical characteristics. Besides, the associated felsic volcanics show A(2)-type granite signatures, such as high Y/Nb (5.97-1.55) and Yb/Ta (9.36-2.57) ratios, consistent with magma derived from continental crust that has been through a cycle of continent-continent collision or an island-arc setting. A localized extension within an overall convergent scenario is interpreted for Sindreth and Punagarh volcanics. This general convergent setting is consistent with the previously proposed Andean-type continental margin for NW Indian block, the Seychelles and Madagascar, all of which lay either at the periphery of Rodinia supercontinent or slightly off the Supercontinent.
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关键词 | E-morb And Oib Like Basalt
lithosphere-asthenosphere Interaction
slab Window
malani Igneous Suite
nw India
rodinia
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收录类别 | SCI
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语种 | 英语
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文献类型 | 期刊论文
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条目标识符 | http://ir.gyig.ac.cn/handle/42920512-1/8653
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专题 | 矿床地球化学国家重点实验室
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作者单位 | 1.State Key Laboratory of Geological Processes and Mineral Resources, School of Earth Sciences, China University of Geosciences, Wuhan 430074, China 2.Department of Geology, University of Rajasthan, Jaipur 302004, Rajasthan, India 3.State Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China
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推荐引用方式 GB/T 7714 |
Wei Wang;Manoj K. Pandit;Jun-Hong Zhao;Wei-Terry Chen;Jian-Ping Zheng. Slab break-off triggered lithosphere - asthenosphere interaction at a convergent margin: The Neoproterozoic bimodal magmatism in NW India[J]. Lithos,2018,296:281-296.
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APA |
Wei Wang;Manoj K. Pandit;Jun-Hong Zhao;Wei-Terry Chen;Jian-Ping Zheng.(2018).Slab break-off triggered lithosphere - asthenosphere interaction at a convergent margin: The Neoproterozoic bimodal magmatism in NW India.Lithos,296,281-296.
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MLA |
Wei Wang;Manoj K. Pandit;Jun-Hong Zhao;Wei-Terry Chen;Jian-Ping Zheng."Slab break-off triggered lithosphere - asthenosphere interaction at a convergent margin: The Neoproterozoic bimodal magmatism in NW India".Lithos 296(2018):281-296.
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