Searched for: author:"Wapenaar, C.P.A."
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van IJsseldijk, J.E. (author), Wapenaar, C.P.A. (author)
The Marchenko method retrieves the responses to virtual sources in the Earth's subsurface from reflection data at the surface, accounting for all orders of multiple reflections. The method is based on two integral representations for focusing- A nd Green's functions. In discretized form, these integrals are represented by finite summations...
journal article 2021
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Wapenaar, C.P.A. (author)
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 a pre-defined location without requiring component decomposition. Our...
conference paper 2020
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Slob, E.C. (author), Wapenaar, C.P.A. (author), Treitel, Sven (author)
Acoustic inversion in one-dimension gives impedance as a function of travel time.<br/>Inverting the reflection response is a linear problem. Recursive methods, from top to bottom or vice versa, are known and use a fundamental wave field that is computed from the reflection response. An integral over the solution to the Marchenko equation, on the...
journal article 2020
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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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Minato, S. (author), Wapenaar, C.P.A. (author), Ghose, R. (author)
To quantitatively image fractures with high resolution, we develop an elastic least-squares migration (LSM) algorithm coupled with linear-slip theory, which accurately addresses seismic wave interaction with thin structures. We derive a linearized waveform inversion using the Born approximation to the boundary integral equation for scattered...
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
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Staring, M. (author), Wapenaar, C.P.A. (author)
In recent years, a variety of Marchenko methods for the attenuation of internal multiples has been developed. These methods have been extensively tested on two-dimensional synthetic data and applied to two-dimensional field data, but only little is known about their behaviour on three-dimensional synthetic data and three-dimensional field...
journal article 2020
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Wapenaar, C.P.A. (author), van IJsseldijk, J.E. (author)
Marchenko imaging is based on 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 a case of imperfect sampling. We have developed discrete representations that account for...
journal article 2020
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Meles, G.A. (author), Zhang, L. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author), Slob, E.C. (author)
Seismic images provided by reverse time migration can be contaminated by artefacts associated with the migration of multiples. Multiples can corrupt seismic images, producing both false positives, that is by focusing energy at unphysical interfaces, and false negatives, that is by destructively interfering with primaries. Multiple prediction...
journal article 2020
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Reinicke Urruticoechea, C. (author), Dukalski, M.S. (author), Wapenaar, C.P.A. (author)
The reflection response of strongly scattering media often contains complicated interferences between primaries and (internal) multiples, which can lead to imaging artifacts unless handled correctly. Internal multiples can be kinematically predicted, for example by the Jakubowicz method or by the inverse scattering series (ISS), as long as...
journal article 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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Wapenaar, C.P.A. (author)
The matrix-vector wave equation is a compact first-order differential equation. It was originally used for the analysis of elastodynamic plane waves in laterally invariant media. It has been extended by various authors for laterally varying media. Other authors derived a similar formalism for other wave phenomena. This paper starts with a...
journal article 2019
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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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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), 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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Almagro Vidal, C. (author), van der Neut, J.R. (author), Wapenaar, C.P.A. (author)
Time-lapse changes in the subsurface can be analyzed by comparing seismic reflection data from two different states, one serving as the base survey and the second as the monitor survey. Conventionally, reflection data are acquired by placing active seismic sources at the acquisition surface. Alternatively, these data can be acquired from passive...
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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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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Reinicke Urruticoechea, C. (author), Wapenaar, C.P.A. (author)
The homogeneous Green’s function is the difference between an impulse response and its time-reversal. According to existing representation theorems, the homogeneous Green’s function associated with source–receiver pairs inside a medium can be computed from measurements at a boundary enclosing the medium. However, in many applications such as...
journal article 2019
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Sripanich, Yanadet (author), Vasconcelos, Ivan (author), Wapenaar, C.P.A. (author)
ABSTRACTThe 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
Searched for: author:"Wapenaar, C.P.A."
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