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Conversations between the Earth and Atmosphere: A study on the seismo-acoustic wavefield

Averbuch, G. (author)

The study of seismo-acoustic events is by no means new. Observations of earthquake-induced infrasound signals are dated back to the 1950s. However, the relative recent deployment of the International Monitoring System (IMS) by the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) provided world coverage for such signals. The continuous...

doctoral thesis 2020

document

Seismoelectromagnetic homogeneous space Green's functions

Slob, E.C. (author), Mulder, M. (author)

We have developed explicit expressions and the corresponding computer code for all homogeneous space Green’s functions for coupled electromagnetic fields and poroelastic waves. The Green’s functions are derived from the basic equations in closed form in the wavenumber- and space-frequency domains. They are given for point sources of any type....

journal article 2016

document

Wave Generation, Propagation and Absorption in CFD Simulations of Free Surface Flows

Duz, B. (author)

The PhD study focused on two topics. The first topic was energy dissipation in wave propagation. The wave dissipation can be caused by physical and/or numerical phenomena, such as the free surface treatment, physical viscosity and artificial viscosity due to discretization of the momentum equations. Among these the free surface treatment is an...

doctoral thesis 2015

document

Models for seismic wave propagation in periodically layered porous media

Kudarova, A. (author), Van Dalen, K.N. (author), Drijkoningen, G.G. (author)

Several models are discussed for seismic wave propagation in periodically layered poroelastic media where layers represent mesoscopic-scale heterogeneities that are larger than the pore and grain sizes but smaller than the wavelength. The layers behave according to Biot’s theory. Wave propagation normal to the layering is considered and the...

conference paper 2014

document

Upscaling in porous media: Consequences of reducing the phase on the dynamic behavior of a homogenized medium

Kudarova, A. (author), van Dalen, K.N. (author), Drijkoningen, G.G. (author)

Effective-medium approaches are widely used to model initially heterogeneous systems: it saves computational time. In poroelasticity (two-phase media), it is advantageous to use one-phase effective medium if possible: it simplifies computations even more. In this paper we discuss situations where phase reduction introduces significant inaccuracy...

conference paper 2014

document

Time-stepping stability of continuous and discontinuous finite-element methods for 3-D wave propagation

Mulder, W.A. (author), Zhebel, E. (author), Minisini, S. (author)

We analyse the time-stepping stability for the 3-D acoustic wave equation, discretized on tetrahedral meshes. Two types of methods are considered: mass-lumped continuous finite elements and the symmetric interior-penalty discontinuous Galerkin method. Combining the spatial discretization with the leap-frog time-stepping scheme, which is second...

journal article 2013

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Validation of an electroseismic and seismoelectric modeling code, for layered earth models, by the explicit homogeneous space solutions

Grobbe, N. (author), Slob, E.C. (author)

We have developed an analytically based, energy fluxnormalized numerical modeling code (ESSEMOD), capable of modeling the wave propagation of all existing ElectroSeismic and SeismoElectric source-receiver combinations in horizontally layered configurations. We compare the results of several of these modeled source-receiver combinations in a...

journal article 2013

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Performance and scalability of finite-difference and finite-element wave-propagation modeling on Intel's Xeon Phi

Zhebel, E. (author), Minisini, S. (author), Kononov, A. (author), Mulder, W.A. (author)

With the rapid developments in parallel compute architectures, algorithms for seismic modeling and imaging need to be reconsidered in terms of parallelization. The aim of this paper is to compare scalability of seismic modeling algorithms: finite differences, continuous mass-lumped finite elements and discontinuous Galerkin finite elements. The...

journal article 2013

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Generalized minimum-phase relations for memory functions associated with wave phenomena

Van Dalen, K.N. (author), Slob, E.C. (author), Schoemaker, C. (author)

journal article 2013

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Effective poroelastic model for one-dimensional wave propagation

Kudarova, A. (author), Van Dalen, K.N. (author), Drijkoningen, G.G. (author)

An effective poroelastic model is proposed that describes seismic attenuation and dispersion in periodically layeredmedia. In this model, the layers represent mesoscopic-scale heterogeneities (larger than the grain and pore sizes but smaller than the wavelength) that can occur both in fluid and solid properties. The proposed effectivemedium is...

journal article 2013

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Local time stepping with the discontinuous Galerkin method for wave propagation in 3D heterogeneous media

Minisini, S. (author), Zhebel, E. (author), Kononov, A. (author), Mulder, W.A. (author)

Modeling and imaging techniques for geophysics are extremely demanding in terms of computational resources. Seismic data attempt to resolve smaller scales and deeper targets in increasingly more complex geologic settings. Finite elements enable accurate simulation of time-dependent wave propagation in heterogeneous media. They are more costly...

journal article 2013

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A Krylov stability-corrected coordinate-stretching metho to simulate wave propagation in unbounded domains

Druskin, V. (author), Remis, R.F. (author)

The Krylov subspace projection approach is a well-established tool for the reducedorder modeling of dynamical systems in the time domain. In this paper, we address the main issues obstructing the application of this powerful approach to the time-domain solution of exterior wave problems. We use frequency-independent perfectly matched layers to...

journal article 2013

document

Data matching for free-surface multiple attenuation by multidimensional deconvolution

Van der Neut, J.R. (author), Frijlink, M. (author), Borselen, R. (author)

A common strategy for surface-related multiple elimination of seismic data is to predict multiples by a convolutional model and subtract these adaptively from the input gathers. Problems can be posed by interfering multiples and primaries. Removing multiples by multidimensional deconvolution (MDD) (inversion) does not suffer from these problems....

journal article 2012

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Fast multifrequency focal beam analysis for 3D seismic acquisition geometry

Wei, W. (author), Fu, L. (author), Blacquiere, G. (author)

A method for the efficient computation of multifrequency focal beams for 3D seismic acquisition geometry analysis has been developed. By computing them for all the frequency components of seismic data, single-frequency focal beams can be extended to multifrequency focal beams. However, this straightforward method involves considerable computer...

journal article 2012

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A bound for the range of a narrow light beam in the near field

Verbeek, P.W. (author), Van den Berg, P.M. (author)

We investigate the possibility of light beams that are both narrow and long range with respect to the wavelength. On the basis of spectral electromagnetic field representations, we have studied the decay of the evanescent waves, and we have obtained some bounds for the width and range of a light beam in the near-field region. The range...

journal article 2011

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True-Amplitude Seismic Imaging Beneath Gas Clouds

Ghazali, A.R. (author)

A gas cloud is a region of gas accumulation in the subsurface, which can severely deteriorate the seismic data quality from deeper reflectors. Due to complex wave propagation through the anomaly and the resulting transmission imprint on the reflections from below this area, the image below the gas cloud is usually not properly recovered. The...

doctoral thesis 2011

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Fluid effect on wave propagation in heterogeneous porous media

Vogelaar, B.B.S.A. (author)

Acoustic wave propagation through porous media is affected by the properties of the pore fluid and the matrix material. The acoustic velocity is extensively used for imaging of subsurface strata, and to predict petrophysical properties. In contrast, the attenuation (loss of wave energy) is not routinely used. This thesis reports the influence of...

doctoral thesis 2009

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Magnetostatic waves in layered materials and devices

Khalili Amiri, P. (author), Rejaei, B. (author)

Magnetostatic wave propagation in multilayers of ferro-/ferrimagnetic and nonmagnetic, dielectric slabs is investigated using an effective medium theory and the transfer matrix method. The propagation in multilayers with antiparallel directions of magnetization is analyzed, in particular. Antiparallel multilayers support (overall) bulk waves at...

journal article 2006

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Nonlinear surface waves over topography

Janssen, T.T. (author)

As ocean surface waves radiate into shallow coastal areas and onto beaches, their lengths shorten, wave heights increase, and the wave shape transforms from nearsinusoidal to the characteristic saw-tooth shapes at the onset of breaking; in the ensuing breaking process the wave energy is cascaded to small-scale turbulent motions in the surf zone....

doctoral thesis 2006

document

Experimental study of blockage of monochromatic waves by counter currents

Suastika, I.K. (author)

Blockage of waves by a current can occur if waves are propagating on a spatially varying opposing current in which the velocity is increasing in the wave propagation direction. The ongoing waves become shorter and steeper while they are propagating against the current. Blocking occurs at the location where the opposing current strength is the...

report 1999