气候变化领域集成服务门户(CCPortal): Complicated Lithospheric Structure Beneath the Contiguous US Revealed by Teleseismic S-Reflections

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DOI	10.1029/2020JB021624
	Complicated Lithospheric Structure Beneath the Contiguous US Revealed by Teleseismic S-Reflections
	Liu T.; Shearer P.M.
发表日期	2021
ISSN	21699313
卷号	126 期号:5
英文摘要	Lithospheric discontinuities, including the lithosphere-asthenosphere boundary (LAB) and the enigmatic mid-lithospheric discontinuities (MLDs), hold important clues about the structure and evolution of tectonic plates. However, P- and S-receiver-function (PRF and SRF) techniques, two traditional techniques to image Earth's deep discontinuities, have some shortcomings in imaging lithosphere discontinuities. Here, we propose a new method using reflections generated by teleseismic S waves (hereafter S-reflections) to image lithospheric discontinuities, which are less affected by multiple phases than PRFs and have better depth resolution than SRFs. We apply this method to the data collected by the Transportable Array and other regional seismic networks and obtain new high-resolution images of the lithosphere below the contiguous US. Beneath the tectonically active Western US, we observe a negative polarity reflector (NPR) in the depth range of 60–110 km, with greatly varying amplitude and depth, which correlates with active tectonic processes. We interpret this feature as the LAB below the Western US. Beneath the tectonically stable Central and Eastern US, we observe two NPRs in the depth ranges of 60–100 km and 100–150 km, whose amplitude and depth also vary significantly, and which appear to correlate with past tectonic processes. We interpret these features as MLDs below the Central and Eastern US. Our results show reasonable agreement with results from PRFs, which have similar depth resolution, suggesting the possibility of joint inversion of S-reflections and PRFs to constrain the properties of lithospheric discontinuities. © 2021. American Geophysical Union. All Rights Reserved.
英文关键词	lithosphere-asthenosphere boundary; mid-lithosphere discontinuities; North America; reflection seismology; teleseismic imaging
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/187126
作者单位	Institute of Geophysics and Planetary Physics, Scripps Institution of Oceanography, University of California, San Diego, San Diego, CA, United States
推荐引用方式 GB/T 7714	Liu T.,Shearer P.M.. Complicated Lithospheric Structure Beneath the Contiguous US Revealed by Teleseismic S-Reflections[J],2021,126(5).
APA	Liu T.,&Shearer P.M..(2021).Complicated Lithospheric Structure Beneath the Contiguous US Revealed by Teleseismic S-Reflections.Journal of Geophysical Research: Solid Earth,126(5).
MLA	Liu T.,et al."Complicated Lithospheric Structure Beneath the Contiguous US Revealed by Teleseismic S-Reflections".Journal of Geophysical Research: Solid Earth 126.5(2021).