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Wapenaar, C.P.A. (author)
With the Marchenko method, it is possible to retrieve the wave field inside a medium from its reflection response at the surface. To date, this method has predominantly been applied to naturally occurring materials. This study extends the Marchenko method for applications in layered metamaterials with, in the low-frequency limit, effective...
journal article 2020
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Wapenaar, C.P.A. (author)
We consider wave propagation problems in which there is a preferred direction of propagation. To account for propagation in preferred directions, the wave equation is decomposed into a set of coupled equations for waves that propagate in opposite directions along the preferred axis. This decomposition is not unique. We discuss flux-normalised...
journal article 2020
document
Wapenaar, C.P.A. (author)
Current Marchenko algorithms require up/down separation, and solving the Marchenko equation enables one to retrieve the up/down components of the Green's function. We propose an iterative scheme to relax the need for up/down separation for focusing. By presenting a visual tour, we show how to retrieve the Green's function in the subsurface at...
conference paper 2020
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Wapenaar, C.P.A. (author)
With the Marchenko method, Green’s functions in the subsurface can be retrieved from seismic reflection data at the surface. State-of-the-art Marchenko methods work well for propagating waves but break down for evanescent waves. This paper discusses a first step towards extending the Marchenko method for evanescent waves and analyses its...
journal article 2020
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Shirmohammadi, F. (author), Weemstra, C. (author), Draganov, D.S. (author), Wapenaar, C.P.A. (author)
poster 2019
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van IJsseldijk, J.E. (author), Wapenaar, C.P.A. (author)
Seismic time-lapse studies are generally concerned with variations in a specific target zone, situated inside an otherwise static medium. In seismic monitoring the entire reflection response at the surface needs to be remodeled for every change in the target zone. Ideally, however, only the response of the target zone is remodeled, which is then...
poster 2019
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Brackenhoff, J.A. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author)
In recent years, progress has been made in the field of virtual seismology. Using the novel data-driven Marchenko method, virtual sources and receivers can be created in the subsurface using only reflection data at the surface of the Earth and a background velocity model of the subsurface. Extensive studies have been performed on the application...
abstract 2019
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Staring, M. (author), Wapenaar, C.P.A. (author)
We apply Marchenko redatuming using an adaptive double-focusing method to 3D field data of the Santos basin, Brazil. This method was already successfully applied to 2D field data and we now study the acquisition geometry and preprocessing requirements in 3D. We start from 3D synthetic data modeled on a dense grid of colocated sources and...
conference paper 2019
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Wapenaar, C.P.A. (author), Reinicke Urruticoechea, C. (author)
Given the increasing interest for non-reciprocal materials, we propose a novel acoustic imaging method for layered non-reciprocal media. The method we propose is a modification of the Marchenko imaging method, which handles multiple scattering between the layer interfaces in a data-driven way. We start by reviewing the basic equations for wave...
journal article 2019
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Reinicke Urruticoechea, C. (author), Dukalski, M.S. (author), Wapenaar, C.P.A. (author)
The elastodynamic Marchenko method removes overburden interactions obscuring the target information. This method either relies on separability of the so-called focusing and Green's functions or requires an accurate initial estimate of the focusing and Green's function overlap. Hitherto, F1- and G-+ have been assumed separable, whereas F1+ and...
conference paper 2019
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Wapenaar, C.P.A. (author), Brackenhoff, J.A. (author), Thorbecke, J.W. (author)
Time-reversal acoustics, seismic interferometry, back propagation, source-receiver redatuming and imaging by double focusing are all based in some way or another on Green's theorem. An implicit assumption for all these methods is that data are available on a closed boundary, a condition that is never met in geophysical practice. As a...
conference paper 2019
document
Brackenhoff, J.A. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author)
Forecasting induced seismicity responses for field data is difficult if no detailed model of the subsurface is available, which generally is the case. As an alternative, reflection data of the subsurface and a non-detailed background model can be used in the Marchenko method to obtain virtual receivers in the subsurface. By employing homogeneous...
conference paper 2019
document
Brackenhoff, J.A. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author)
To enhance monitoring of the subsurface, virtual sources and receivers inside the subsurface can be created from seismic reflection data at the surface of the Earth using the Marchenko method. The response between these virtual sources and receivers can be obtained through the use of homogeneous Green's function retrieval. A homogeneous Green's...
journal article 2019
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Wapenaar, C.P.A. (author), van IJsseldijk, J.E. (author)
The Marchenko method is based on two integral representations for focusing functions and Green’s functions. In practice the integrals are replaced by finite summations. This works well for regularly sampled data, but the quality of the results degrades in case of imperfect sampling. We reformulate the integral representations into summation...
conference paper 2019
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Zhang, L. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author), Slob, E.C. (author)
We have compared three data-driven internal multiple reflection elimination schemes derived from the Marchenko equations and inverse scattering series (ISS). The two schemes derived from Marchenko equations are similar but use different truncation operators. The first scheme creates a new data set without internal multiple reflections. The...
journal article 2019
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Meles, G.A. (author), van der Neut, J.R. (author), van Dongen, K.W.A. (author), Wapenaar, C.P.A. (author)
Wavefield focusing can be achieved by Time-Reversal Mirrors, which involve in- and output signals that are infinite in time and waves propagating through the entire medium. Here, an alternative solution for wavefield focusing is presented. This solution is based on a new integral representation where in- and output signals are finite in time,...
conference paper 2019
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Sripanich, Yanadet (author), Vasconcelos, Ivan (author), Wapenaar, C.P.A. (author)
The Marchenko method retrieves Green's functions between the acquisition surface and any arbitrary point in the medium. The process generally involves solving an inversion starting with an initial focusing function, e.g., a direct-wave Green's function from the desired subsurface position, typically obtained using an approximate velocity...
journal article 2019
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Minato, S. (author), Ghose, R. (author), Wapenaar, C.P.A. (author)
Characterizing the mechanical and hydraulic properties of fractures is crucial in hydrocarbon and geothermal field development. Contrary to passive microseismic measurements, active seismic measurements using a borehole, e.g., VSP or sonic logging, have a potential to address aseismic fractures. However, there is a considerable scale gap between...
conference paper 2019
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Minato, S. (author), Ghose, R. (author), Wapenaar, C.P.A. (author)
Characterizing subsurface fractures is a key to developing hydrocarbon and geothermal fields, as well as providing fundamental information on fracture system relevant to regional seismotectonics. Seismic characterization of fractures has generally been based on the effective medium theory, which considers seismically invisible small fractures....
conference paper 2019
document
Minato, S. (author), Ghose, R. (author), Wapenaar, C.P.A. (author)
Single-well reflection imaging using sonic logging data successfully locates fine-scale structures around a borehole including fractures. In order to achieve accurate and quantitative estimation of fracture properties with high resolution, we propose to couple least-squares migration with linear slip theory. The proposed least-squares...
conference paper 2019
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