气候变化领域集成服务门户(CCPortal): Upper mantle tomography beneath the Pacific Northwest interior

CCPortal

DOI	10.1016/j.epsl.2020.116214
	Upper mantle tomography beneath the Pacific Northwest interior
	Stanciu A.C.; Humphreys E.D.
发表日期	2020
ISSN	0012821X
卷号	539
英文摘要	The Pacific Northwest has undergone extensive tectonic and magmatic construction in the Cenozoic, and many clues to its history are in a well-resolved upper mantle structure. We present new P, S, and VP/VS models that benefit from improved algorithms and additional data from recently deployed flexible array experiments in the region of the Columbia River Basalts, western Snake River Plain, and Idaho Batholith. We refine the geometries of previously imaged structures and identify new anomalies beneath the Pacific Northwest. A clear separation is resolved between the Wallowa and Idaho structures that extends from the base of the crust to the depth extent of these structures. The separation follows the Precambrian margin of North America, possibly indicating separate tectonic histories for the two structures. A shallow fast anomaly beneath Idaho Batholith may be responsible for the observed curvature of the Yellowstone track around this batholith. And a strong and unusually deep (180–250 km) slow anomaly is present east of the apparent Juan de Fuca slab gap. Resolving these structures well is important in understanding the origin of the lithospheric fragments in the mantle, and key to any reconstruction of the evolution of the Pacific Northwest-Farallon-Kula-Juan de Fuca tectonic system. Of most relevance, understanding the origin of the imaged high-velocity mantle structures provides strong constraint on their density, that otherwise would be largely unknown, which controls the evolution of vertical and horizontal stresses acting at the base of the lithosphere and hence the evolution of topography. Also, resolving the volumes of partially molten upper mantle shapes our understanding on the origin of the abundant volcanism in the Pacific Northwest interior. © 2020 Elsevier B.V.
关键词	Farallon Pacific Northwest ray tracing ray weighting seismic tomography Wallowa
英文关键词	Ray tracing; Seismology; Separation; Tectonics; Topography; Farallon; Pacific Northwest; ray weighting; Seismic tomography; Wallowa; Structural geology; batholith; lithospheric structure; mantle structure; ray tracing; seismic tomography; upper mantle; volcanism; California; Columbia River; Farallon Islands; Idaho; Idaho; Pacific Northwest; Snake River Plain; United States
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202903
作者单位	Department of Earth Sciences, University of Oregon, 1272 University of Oregon, Eugene, OR 97403, United States
推荐引用方式 GB/T 7714	Stanciu A.C.,Humphreys E.D.. Upper mantle tomography beneath the Pacific Northwest interior[J],2020,539.
APA	Stanciu A.C.,&Humphreys E.D..(2020).Upper mantle tomography beneath the Pacific Northwest interior.Earth and Planetary Science Letters,539.
MLA	Stanciu A.C.,et al."Upper mantle tomography beneath the Pacific Northwest interior".Earth and Planetary Science Letters 539(2020).