气候变化领域集成服务门户(CCPortal): Petrofabrics and Seismic Properties of Himalayan Amphibolites: Implications for a Thick Anisotropic Deep Crust Beneath Southern Tibet

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DOI	10.1029/2019JB018700
	Petrofabrics and Seismic Properties of Himalayan Amphibolites: Implications for a Thick Anisotropic Deep Crust Beneath Southern Tibet
	Li W.; Zhang J.; Wang X.; Wang Y.; Wu X.; Hu Z.
发表日期	2020
ISSN	21699313
卷号	125 期号:8
英文摘要	The bulk composition of overthickened Tibetan deep crust has been generally believed to be mafic granulite with eclogite at the lowermost crust. However, a granulitic/eclogitic deep crust is in contradiction to geological and geophysical observations in southern Tibet. Here we present petrofabrics and seismic properties of amphibolites from exhumed crustal part of the Indian plate in the eastern Himalayan syntaxis. Our results show strong fabrics of amphibole, nearly random fabrics of plagioclase and strong seismic anisotropies of amphibolites (AVp = 5.6–12.0% and Max. AVs = 5.1–7.7%). Comparing to a deep crust composed of nearly isotropic mafic granulite and weakly anisotropic eclogite, a thick amphibolitic layer in the middle-lower crust would better account for the strong shear wave splitting (0.2–0.5 s in delay times or 4–15% in S wave anisotropy), the suture boundary parallel faster shear wave polarization, and the widespread postcollisional adakite-like potassic rocks in southern Tibet. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	amphibolite; middle-lower crust; petrofabric; seismic properties; shear wave splitting; southern Tibet
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187715
作者单位	State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan, China; Center for Global Tectonics, School of Earth Sciences, China University of Geosciences, Wuhan, China
推荐引用方式 GB/T 7714	Li W.,Zhang J.,Wang X.,et al. Petrofabrics and Seismic Properties of Himalayan Amphibolites: Implications for a Thick Anisotropic Deep Crust Beneath Southern Tibet[J],2020,125(8).
APA	Li W.,Zhang J.,Wang X.,Wang Y.,Wu X.,&Hu Z..(2020).Petrofabrics and Seismic Properties of Himalayan Amphibolites: Implications for a Thick Anisotropic Deep Crust Beneath Southern Tibet.Journal of Geophysical Research: Solid Earth,125(8).
MLA	Li W.,et al."Petrofabrics and Seismic Properties of Himalayan Amphibolites: Implications for a Thick Anisotropic Deep Crust Beneath Southern Tibet".Journal of Geophysical Research: Solid Earth 125.8(2020).