气候变化领域集成服务门户(CCPortal): Breakup of Eastern Gondwana as inferred from the Lower Cretaceous Charong Dolerites in the central Tethyan Himalaya; southern Tibet

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DOI	10.1016/j.palaeo.2017.10.010
	Breakup of Eastern Gondwana as inferred from the Lower Cretaceous Charong Dolerites in the central Tethyan Himalaya; southern Tibet
	Zeng Y.-C.; Xu J.-F.; Chen J.-L.; Wang B.-D.; Huang F.; Yu H.-X.; Chen X.-F.; Zhao P.-P.
发表日期	2019
ISSN	0031-0182
起始页码	70
结束页码	82
卷号	515
英文摘要	The separation of the Indian Plate from the Australia–Antarctic Plate and its accretion to the Eurasian Plate is the key to understanding the evolutionary history and paleogeographic reconstruction of Eastern Gondwana in the Jurassic–Cretaceous. In this paper, zircon U–Pb dating indicates that the Charong Dolerites (~ 142 Ma) are newly recognized Lower Cretaceous magmatic rocks in the central Tethyan Himalaya in southern Tibet. These dolerites are characterized by moderate contents of SiO 2 (49.9–56.9 wt%), high contents of MgO (4.66–9.69 wt%) and TiO 2 (2.20–2.81 wt%), high Zr/Y ratios (7.5–13.1), enrichments in Rb and Th, moderately negative Nb–Ta anomalies, and no Zr–Hf anomalies. Taking into account the narrow range of whole-rock initial 87 Sr/ 88 Sr ratios (0.7068 to 0.7086), the negative values of ε Nd (t) (− 2.4 to − 4.1), and the geochemical makeup of the zircons, the Charong Dolerites are akin to continental basalts, indicating that the central Tethyan Himalayan area was in an extensional setting during the Early Cretaceous. Although the Charong Dolerites indicate a relatively high mantle-melting temperature (~ 1469 ± 44 °C), this is still lower than the temperature required for a mantle plume origin. In combination with the Lower Cretaceous mafic rocks in the eastern Himalaya and the coeval volcaniclastic sediments, we suggest that the Charong Dolerites were partial melts of a rising asthenospheric mantle, this process having been triggered by rifting between the Indian Plate and the Australia–Antarctic Plate. This episode of continental lithospheric extension may have led to the opening of a post-Neotethyan oceanic basin that extended between the Indian Craton and the Tethyan Himalaya during the late Early Cretaceous, a feature that is highly significant in paleogeographic reconstructions of Eastern Gondwana. © 2017 Elsevier B.V.
英文关键词	Continental basalt; Crustal recycling; Geochemistry; Neotethyan Ocean; Zircon
语种	英语
scopus关键词	basalt; craton; Cretaceous; dating method; diabase; Eurasian plate; geochemistry; Gondwana; Indian plate; Jurassic-Cretaceous boundary; mantle plume; ocean basin; paleogeography; reconstruction; temperature effect; volcaniclastic deposit; zircon; Australia; China; Himalayas; Xizang
来源期刊	Palaeogeography, Palaeoclimatology, Palaeoecology
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/151124
作者单位	State Key Laboratory of Geological Processes and Mineral Resources, School of Earth Science and Resources, China University of Geosciences, Beijing, 100083, China; State Key Laboratory of Isotope Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing, 100101, China; Chengdu Institute of Geology and Mineral Resources, Chengdu, 610081, China; School of Earth Science, Guilin University of Technology, Guilin, 541004, China; College of Resources, Hebei GEO University, Shijiazhuang, 050031, China
推荐引用方式 GB/T 7714	Zeng Y.-C.,Xu J.-F.,Chen J.-L.,et al. Breakup of Eastern Gondwana as inferred from the Lower Cretaceous Charong Dolerites in the central Tethyan Himalaya; southern Tibet[J],2019,515.
APA	Zeng Y.-C..,Xu J.-F..,Chen J.-L..,Wang B.-D..,Huang F..,...&Zhao P.-P..(2019).Breakup of Eastern Gondwana as inferred from the Lower Cretaceous Charong Dolerites in the central Tethyan Himalaya; southern Tibet.Palaeogeography, Palaeoclimatology, Palaeoecology,515.
MLA	Zeng Y.-C.,et al."Breakup of Eastern Gondwana as inferred from the Lower Cretaceous Charong Dolerites in the central Tethyan Himalaya; southern Tibet".Palaeogeography, Palaeoclimatology, Palaeoecology 515(2019).