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Wapenaar, C.P.A. (author), Slob, E.C. (author)
Inspired by recent developments in wave propagation and scattering experiments with parity-time (PT) symmetric materials, we discuss reciprocity and representation theorems for 3D inhomogeneous PT-symmetric materials and indicate some applications. We start with a unified matrix-vector wave equation which accounts for acoustic, quantum...
journal article 2022
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van der Neut, J.R. (author), Brackenhoff, Joeri (author), Meles, Giovanni Angelo (author), Slob, E.C. (author), Wapenaar, C.P.A. (author)
By solving a Marchenko equation, Green’s functions at an arbitrary (inner) depth level inside an unknown elastic layered medium can be retrieved from single-sided reflection data, which are collected at the top of the medium. To date, it has only been possible to obtain an exact solution if the medium obeyed stringent monotonicity conditions and...
journal article 2022
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Wapenaar, C.P.A. (author), de Ridder, Sjoerd (author), Dukalski, Marcin (author), Reinicke, Christian (author)
Standard Marchenko redatuming and imaging schemes neglect evanescent waves and are based on the assumption that decomposition into downgoing and upgoing waves is possible in the subsurface. Recently we have shown that propagator matrices, which circumvent these assumptions, can be expressed in terms of Marchenko focusing functions. In this paper...
conference paper 2022
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Dukalski, Marcin (author), Reinicke, Christian (author), Wapenaar, C.P.A. (author)
Marchenko equation-based methods promise data-driven, true-amplitude internal multiple elimination. The method is exact in 1-D acoustic media, however it needs to be expanded to account for the presence of 2- and 3-D elastodynamic wave-field phenomena, such as compressional (P) to shear (S) mode conversions, total reflections or evanescent waves...
conference paper 2022
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Thorbecke, J.W. (author), Zhang, L. (author), Wapenaar, C.P.A. (author), Slob, E.C. (author)
The Marchenko multiple elimination (MME) and transmission compensation schemes retrieve primary reflections in the two-way traveltime domain without model information or using adaptive subtraction. Both schemes are derived from projected Marchenko equations and are similar to each other, but they use different time-domain truncation operators...
journal article 2021
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Staring, M. (author), Dukalski, Marcin (author), Belonosov, Mikhail (author), Baardman, Rolf H. (author), Yoo, Jewoo (author), Hegge, Rob F. (author), Borselen, Roald van (author), Wapenaar, C.P.A. (author)
Suppression of surface-related and internal multiples is an outstanding challenge in seismic data processing. The former is particularly difficult in shallow water, whereas the latter is problematic for targets buried under complex, highly scattering overburdens. We have developed a two-step, amplitude- and phase-preserving, inversion-based...
journal article 2021
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Shirmohammadi, F. (author), Draganov, D.S. (author), Wapenaar, C.P.A. (author)
Seismic interferometry (SI) refers to the principle of generating seismic responses by crosscorrelating seismic observations at different receiver locations. Theory requires that the boundary sources emit the same energy, have regular spacing and are spaced densely enough. When these assumptions are not met, not only the desired physical...
poster 2021
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van der Neut, J.R. (author), Brackenhoff, J. (author), Meles, G. (author), Zhang, L. (author), Slob, E.C. (author), Wapenaar, C.P.A. (author)
Green’s functions in an unknown medium can be retrieved from single-sided reflection data by solving a multidimensional Marchenko equation. This methodology requires knowledge of the direct wavefield throughout the medium, which should include forward-scattered waveforms. In practice, the direct field is often computed in a smooth background...
conference paper 2021
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Wapenaar, C.P.A. (author), Ridder, Sjoerd de (author)
The propagator matrix “propagates” a full wave field from one depth level to another, accounting for all propagation angles and evanescent waves. The Marchenko focusing function forms the nucleus of data-driven Marchenko redatuming and imaging schemes, accounting for internal multiples. These seemingly different concepts appear to be closely...
journal article 2021
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Wapenaar, C.P.A. (author), Snieder, Roel (author), Ridder, Sjoerd de (author), Slob, E.C. (author)
Marchenko redatuming, imaging, monitoring and multiple elimination methods are based on Green’s function representations, with the underlying assumption that the wave field in the subsurface can be decomposed into downgoing and upgoing waves and that evanescent waves can be neglected. In this paper we show that up/down decomposition in the...
book chapter 2021
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Kiraz, Mert S. R. (author), Snieder, Roel (author), Wapenaar, C.P.A. (author)
Marchenko algorithms retrieve the Green’s function for arbitrary subsurface locations, and the retrieved Green’s function includes the primary and multiple reflected waves. The Marchenko algorithms require the estimate of the direct arrivals and the reflected waves; however, most previous Marchenko algorithms also require the up/down components...
book chapter 2021
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Almobarak, M. (author), van IJsseldijk, J.E. (author), Wapenaar, C.P.A. (author)
Seismic imaging is often used to interpret subsurface formations. However, images obtained by conventional methods are contaminated with internal multiples. The Marchenko method provides the means to obtain multiple-free subsurface images. Due to the high computational cost of the conventional point-source Marchenko imaging method, the less...
conference paper 2021
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van IJsseldijk, J.E. (author), Wapenaar, C.P.A. (author)
4D seismic studies aim to observe time-lapse changes in the subsurface between a baseline and a monitor study. These changes are generally small, and the seismic response from a deep reservoir can be concealed by reflections from shallow structures. Here, we introduce a novel way of isolating the reservoir response by means of the Marchenko...
book chapter 2021
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Wapenaar, C.P.A. (author), Brackenhoff, J.A. (author), Dukalski, Marcin (author), Meles, G.A. (author), Slob, E.C. (author), Staring, M. (author), Thorbecke, J.W. (author), van der Neut, J.R. (author), Zhang, L. (author), Reinicke Urruticoechea, C. (author)
With the Marchenko method it is possible to retrieve Green's functions between virtual sources in the subsurface and receivers at the surface from reflection data at the surface and focusing functions. A macro model of the subsurface is needed to estimate the first arrival; the internal multiples are retrieved entirely from the reflection data....
journal article 2021
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Brackenhoff, J.A. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author)
We create virtual sources and receivers in a 3-D subsurface using the previously derived single-sided homogeneous Green's function representation. We employ Green's functions and focusing functions that are obtained using reflection data at the Earth's surface, a macrovelocity model, and the Marchenko method. The homogeneous Green's function is...
journal article 2021
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Kiraz, Mert S. R. (author), Snieder, Roel (author), Wapenaar, C.P.A. (author)
The Gel'fand-Levitan equation, the Gopinath-Sondhi equation, and the Marchenko equation are developed for one-dimensional inverse scattering problems. Recently, a version of the Marchenko equation based on wavefield decomposition has been introduced for focusing waves in multi dimensions. However, wavefield decomposition is a limitation when...
journal article 2021
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Reinicke Urruticoechea, C. (author), Dukalski, Marcin (author), Wapenaar, C.P.A. (author)
Correct handling of strong elastic, internal, multiples remains a challenge for seismic imaging. Methods aimed at eliminating them are currently limited by monotonicity violations, a lack of a-priori knowledge about mode conversions, or unavailability of multi-component sources and receivers for not only particle velocities but also the traction...
journal article 2021
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Wapenaar, C.P.A. (author), Snieder, Roel (author), de Ridder, Sjoerd (author), Slob, E.C. (author)
Marchenko methods are based on integral representations which express Green’s functions for virtual sources and/or receivers in the subsurface in terms of the reflection response at the surface. An underlying assumption is that inside the medium the wave field can be decomposed into downgoing and upgoing waves and that evanescent waves can be...
journal article 2021
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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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Pijnenburg, R. (author), Laumann, S.J. (author), Wessels, R. (author), Maat, G. Ter (author), Armstrong, L.S. (author), Vardon, P.J. (author), Bruhn, D.F. (author), Barnhoorn, A. (author), Wapenaar, C.P.A. (author)
The European Plate Observing System - Netherlands (EPOS-NL) is the Dutch research infrastructure for solid Earth sciences. EPOS-NL is a cluster of large-scale geophysical facilities for research on georesources and geohazards. It is a partnership between Delft University of Technology (TU Delft), the Royal Netherlands Meteorological Institute...
conference paper 2021
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