气候变化领域集成服务门户(CCPortal): Modeling the Acoustic Flux Inside the Magmatic Conduit by 3D-FDTD Simulation

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DOI	10.1029/2019JB018849
	Modeling the Acoustic Flux Inside the Magmatic Conduit by 3D-FDTD Simulation
	Lacanna G.; Ripepe M.
发表日期	2020
ISSN	21699313
卷号	125 期号:6
英文摘要	Infrasound measurements at open-vent volcanoes are crucial parameters for monitoring and exploring the explosive source dynamics. Volcano infrasound depicts the pressure variation within the volcanic conduit generated by the sudden expansion of volcanic gases during the fragmentation process, and it can provide important constraints on the explosive source parameters (i.e., volumetric flux and exit velocity). The acoustic source of volcanic explosions is modeled by infrasonic signals measured near the volcano vent (<3 km) assuming linear theory of sound and considering the effects of topography and atmosphere on the acoustic wavefield. However, little is known on the initial conditions within the volcanic conduit. In linear acoustics, the wavefield in a cylindrical duct propagates as a plane wavefront, which becomes spherical outside the vent. The acoustic impedance at the open end of the duct is a function of the vent radius and the pressure wavelength, and it controls the acoustic wavefield radiated outside the duct in terms of amplitude and radiation pattern. We present here a 3D-Finite Difference Time Domain (FDTD) numerical method to evaluate the scattering effects on the infrasound signal produced by topography around the crater and along the source-receiver path in terms of Green's function. Once the effects of topography are removed, we show how pressure perturbation is largely affected by the impedance contrast at the vent which, when not considered, is introducing errors in the way we quantify explosive dynamics. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	3D-FDTD; infrasound propagation; source inversion; volumetric flux
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/187811
作者单位	Department of Earth Sciences, University of Florence, Florence, Italy
推荐引用方式 GB/T 7714	Lacanna G.,Ripepe M.. Modeling the Acoustic Flux Inside the Magmatic Conduit by 3D-FDTD Simulation[J],2020,125(6).
APA	Lacanna G.,&Ripepe M..(2020).Modeling the Acoustic Flux Inside the Magmatic Conduit by 3D-FDTD Simulation.Journal of Geophysical Research: Solid Earth,125(6).
MLA	Lacanna G.,et al."Modeling the Acoustic Flux Inside the Magmatic Conduit by 3D-FDTD Simulation".Journal of Geophysical Research: Solid Earth 125.6(2020).