气候变化领域集成服务门户(CCPortal): Seismic Structure, Gravity Anomalies and Flexure Along the Emperor Seamount Chain

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DOI	10.1029/2020JB021109
	Seismic Structure, Gravity Anomalies and Flexure Along the Emperor Seamount Chain
	Watts A.B.; Grevemeyer I.; Shillington D.J.; Dunn R.A.; Boston B.; Gómez de la Peña L.
发表日期	2021
ISSN	21699313
卷号	126 期号:3
英文摘要	The Hawaiian-Emperor seamount chain in the Pacific Ocean has provided fundamental insights into hotspot generated intraplate volcanism and the long-term strength of oceanic lithosphere. However, only a few seismic experiments to determine crustal and upper mantle structure have been carried out on the Hawaiian Ridge, and no deep imaging has ever been carried out along the Emperor seamounts. Here, we present the results of an active source seismic experiment using 29 Ocean-Bottom Seismometers (OBS) carried out along a strike profile of the seamounts in the region of Jimmu and Suiko guyots. Joint reflection and refraction tomographic inversion of the OBS data show the upper crust is highly heterogeneous with P wave velocities <4–5 km s−1, which are attributed to extrusive lavas and clastics. In contrast, the lower crust is remarkably homogeneous with velocities of 6.5–7.2 km s−1, which we attribute to oceanic crust and mafic intrusions. Moho is identified by a strong PmP arrival at offsets of 20–80 km, yielding depths of 13–16 km. The underlying mantle is generally homogeneous with velocities in the range 7.9–8.0 km s−1. The crust and mantle velocity structure has been verified by gravity modeling. While top of oceanic crust prior to volcano loading is not recognized as a seismic or gravity discontinuity, flexural modeling reveals a ∼5.0–5.5 km thick preexisting oceanic crust that is overlain by a ∼8 km thick volcanic edifice. Unlike at the Hawaiian Ridge, we find no evidence of magmatic underplating. © 2021. The Authors.
英文关键词	gravity and isostasy; marine geology & geophysics; marine seismics; oceanic hotspots and intraplate volcanism; seafloor morphology
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/187319
作者单位	Department of Earth Sciences, University of Oxford, Oxford, United Kingdom; GEOMAR Helmholtz Centre for Ocean Research, Kiel, Germany; School of Earth and Sustainability, Northern Arizona University, Flagstaff, AZ, United States; Department of Earth Sciences, School of Ocean and Earth Science and Technology, University of Hawaii, Honolulu, HI, United States; Lamont Doherty Earth Observatory of Columbia University, University of Columbia, Palisades, NY, United States
推荐引用方式 GB/T 7714	Watts A.B.,Grevemeyer I.,Shillington D.J.,et al. Seismic Structure, Gravity Anomalies and Flexure Along the Emperor Seamount Chain[J],2021,126(3).
APA	Watts A.B.,Grevemeyer I.,Shillington D.J.,Dunn R.A.,Boston B.,&Gómez de la Peña L..(2021).Seismic Structure, Gravity Anomalies and Flexure Along the Emperor Seamount Chain.Journal of Geophysical Research: Solid Earth,126(3).
MLA	Watts A.B.,et al."Seismic Structure, Gravity Anomalies and Flexure Along the Emperor Seamount Chain".Journal of Geophysical Research: Solid Earth 126.3(2021).