气候变化领域集成服务门户(CCPortal): Shear Velocity and Radial Anisotropy beneath Southwestern Canada: Evidence for Crustal Extension and Thick-Skinned Tectonics

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DOI	10.1029/2019JB018310
	Shear Velocity and Radial Anisotropy beneath Southwestern Canada: Evidence for Crustal Extension and Thick-Skinned Tectonics
	Wang J.; Gu Y.J.; Chen Y.
发表日期	2020
ISSN	21699313
卷号	125 期号:2
英文摘要	Deformation-associated craton assembly and Cordilleran orogenesis played major roles during the crustal formation beneath the western margin of North America. To improve the understanding of the deformation history in this region, we investigate the crustal shear velocity and anisotropy by analyzing fundamental mode Rayleigh and Love waves from ambient seismic noise. Continuous recordings from 118 regional broadband stations reveal lateral variations in both velocity and anisotropy with strong spatial affinities to major geological domains. Strong variations in radial anisotropy, which dips westward and extends to at least midcrustal depths, suggest a “thick-skinned” foreland thrust-and-fold belt beneath the Canadian Rocky Mountains. Our regional data also suggest increased horizontal shear velocities beneath the southern Canadian Cordillera, particularly near the Omineca Belt, which may have resulted from strong zonal deformation within the Cordilleran crust. This anisotropic anomaly migrates southward, and its spatial extent agrees well with the normal fault distribution to the west of the Rocky Mountain Trench. Our observations offer new evidence for the Eocene extension of the orogenic hinterland during the trans-tensional motion of the Cordillera to the North American craton. ©2020. American Geophysical Union. All Rights Reserved.
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/187987
作者单位	Department of Physics, University of Alberta, Edmonton, AB, Canada; Now at Deep Earth Imaging, Future Science Platform, CSIRO, Perth, WA, Australia
推荐引用方式 GB/T 7714	Wang J.,Gu Y.J.,Chen Y.. Shear Velocity and Radial Anisotropy beneath Southwestern Canada: Evidence for Crustal Extension and Thick-Skinned Tectonics[J],2020,125(2).
APA	Wang J.,Gu Y.J.,&Chen Y..(2020).Shear Velocity and Radial Anisotropy beneath Southwestern Canada: Evidence for Crustal Extension and Thick-Skinned Tectonics.Journal of Geophysical Research: Solid Earth,125(2).
MLA	Wang J.,et al."Shear Velocity and Radial Anisotropy beneath Southwestern Canada: Evidence for Crustal Extension and Thick-Skinned Tectonics".Journal of Geophysical Research: Solid Earth 125.2(2020).