气候变化领域集成服务门户(CCPortal): Simulation of Topography Effects on Rockfall-Generated Seismic Signals: Application to Piton de la Fournaise Volcano

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DOI	10.1029/2020JB019874
	Simulation of Topography Effects on Rockfall-Generated Seismic Signals: Application to Piton de la Fournaise Volcano
	Kuehnert J.; Mangeney A.; Capdeville Y.; Métaxian J.P.; Bonilla L.F.; Stutzmann E.; Chaljub E.; Boissier P.; Brunet C.; Kowalski P.; Lauret F.; Hibert C.
发表日期	2020
ISSN	21699313
卷号	125 期号:10
英文摘要	Seismic waves generated by rockfalls contain valuable information on the properties of these events. However, as rockfalls mainly occur in mountainous regions, the generated seismic waves can be affected by strong surface topography variations. We present a methodology for investigating the influence of topography using a Spectral-Element-based simulation of 3-D wave propagation in various geological media. This methodology is applied here to Dolomieu crater on the Piton de la Fournaise volcano, Reunion Island, but it can be used for other sites, taking into account local topography and medium properties. The complexity of wave fields generated by single-point forces is analyzed for different velocity models and topographies. Ground-motion amplification is studied relative to flat reference models, showing that Peak Ground Velocity (PGV) and total kinetic energy can be amplified by factors of up to 10 and 20, respectively. Simulations with Dolomieu-like crater shapes suggest that curvature variations are more influential than depth variations. Topographic effects on seismic signals from rockfalls at Dolomieu crater are revealed by interstation spectral ratios. Results suggest that propagation along the topography rather than source direction dominates the spectral ratios and that resulting radiation patterns can be neglected. The seismic signature of single rockfall impacts is studied. Using Hertz contact theory, impact force and duration are estimated and then used to scale simulations, achieving order-of-magnitude agreement with observed signal amplitudes and frequency thresholds. Our study shows that combining Hertz theory with high-frequency seismic wave simulations on real topography improves the quantitative analysis of rockfall seismic signals. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	Rockfall; Seismic waves; Spectral Element Simulations; Volcano topography
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/187564
作者单位	Université de Paris, Institut de Physique du Globe de Paris, CNRS, Paris, France; Laboratoire de Planétologie et Géodynamique, UMR CNRS 6112, Université de Nantes, Nantes, France; Université Gustave Eiffel, Marne-la-Vallée, France; Université Grenoble Alpes, Univversité Savoie Mont Blanc, CNRS, IRD, IFSTTAR, ISTerre, Grenoble, France; Observatoire Volcanologique du Piton de la Fournaise, Institut de Physique du Globe de Paris, CNRS UMS 3454 & UMR 7154, La Plaine des Cafres, France; Université de Strasbourg, CNRS, EOST/IPGS UMR 7516, Strasbourg, France
推荐引用方式 GB/T 7714	Kuehnert J.,Mangeney A.,Capdeville Y.,et al. Simulation of Topography Effects on Rockfall-Generated Seismic Signals: Application to Piton de la Fournaise Volcano[J],2020,125(10).
APA	Kuehnert J..,Mangeney A..,Capdeville Y..,Métaxian J.P..,Bonilla L.F..,...&Hibert C..(2020).Simulation of Topography Effects on Rockfall-Generated Seismic Signals: Application to Piton de la Fournaise Volcano.Journal of Geophysical Research: Solid Earth,125(10).
MLA	Kuehnert J.,et al."Simulation of Topography Effects on Rockfall-Generated Seismic Signals: Application to Piton de la Fournaise Volcano".Journal of Geophysical Research: Solid Earth 125.10(2020).