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Wavefield focusing using a generalised, potentially asymmetric homogeneous Green's function

Diekmann, Leon (author), Vasconcelos, Ivan (author), Wapenaar, C.P.A. (author), Slob, E.C. (author), Snieder, Roel (author)

Marchenko-type integrals typically relate so-called focusing functions and Green's functions via the reflection response measured on the open surface of a volume of interest. Originating from one dimensional inverse scattering theory, the extension to two and three dimensions set in motion various new developments regarding imaging in complex...

journal article 2023

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On the retrieval of forward-scattered waveforms from acoustic reflection and transmission data with the Marchenko equation

van der Neut, J.R. (author), Brackenhoff, J.A. (author), Meles, G.A. (author), Zhang, L. (author), Slob, E.C. (author), Wapenaar, C.P.A. (author)

A Green's function in an acoustic medium can be retrieved from reflection data by solving a multidimensional Marchenko equation. This procedure requires a priori knowledge of the initial focusing function, which can be interpreted as the inverse of a transmitted wavefield as it would propagate through the medium, excluding (multiply)...

journal article 2022

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Reciprocity and Representations for Wave Fields in 3D Inhomogeneous Parity-Time Symmetric Materials

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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Marchenko Green’s Function Retrieval in Layered Elastic Media from Two-Sided Reflection and Transmission Data

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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Green’s function representations for Marchenko imaging without up/down decomposition

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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Implementation of the Marchenko multiple elimination algorithm

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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Marchenko redatuming, imaging and multiple elimination, and their mutual relations

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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Data-driven retrieval of primary plane-wave responses

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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Tutorial: unified 1D inversion of the acoustic reflection response

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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Transmission compensated primary reflection retrieval in the data domain and consequences for imaging

Zhang, L. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author), Slob, E.C. (author)

We have developed a scheme that retrieves primary reflections in the two-way traveltime domain by filtering the data. The data have their own filter that removes internal multiple reflections, whereas the amplitudes of the retrieved primary reflections are compensated for two-way transmission losses. Application of the filter does not require...

journal article 2019

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Data-driven internal multiple elimination and its consequences for imaging: A comparison of strategies

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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Virtual acoustics in inhomogeneous media with single-sided access

Wapenaar, C.P.A. (author), Brackenhoff, J.A. (author), Thorbecke, J.W. (author), van der Neut, J.R. (author), Slob, E.C. (author), Verschuur, D.J. (author)

A virtual acoustic source inside a medium can be created by emitting a time-reversed point-source response from the enclosing boundary into the medium. However, in many practical situations the medium can be accessed from one side only. In those cases the time-reversal approach is not exact. Here, we demonstrate the experimental design and...

journal article 2018

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Single- and Double-Sided Marchenko Imaging Conditions in Acoustic Media

van der Neut, J.R. (author), Brackenhoff, Joeri (author), Staring, Myrna (author), Zhang, L. (author), de Ridder, S.A.L. (author), Slob, E.C. (author), Wapenaar, C.P.A. (author)

journal article 2018

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Artifact-free reverse time migration

Zhang, L. (author), Slob, E.C. (author), van der Neut, J.R. (author), Wapenaar, C.P.A. (author)

We have derived an improved reverse time migration (RTM) scheme to image the medium without artifacts arising from internal multiple reflections. This is based on a revised implementation of Marchenko redatuming using a new time-truncation operator. Because of the new truncation operator, we can use the time-reversed version of the standard...

journal article 2018

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Implementation of the marchenko method

Thorbecke, J.W. (author), Slob, E.C. (author), Brackenhoff, J.A. (author), van der Neut, J.R. (author), Wapenaar, C.P.A. (author)

The Marchenko method makes it possible to compute subsurface-to-surface Green's functions from reflection measurements at the surface. Applications of the Marchenko method have already been discussed in many papers, but its implementation aspects have not yet been discussed in detail. Solving the Marchenko equation is an inverse problem. The...

journal article 2017

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A Marchenko equation for acoustic inverse source problems

van der Neut, J.R. (author), Johnson, Jami L. (author), van Wijk, K. (author), Singh, S. (author), Slob, E.C. (author), Wapenaar, C.P.A. (author)

From acoustics to medical imaging and seismology, one strives to make inferences about the structure of complex media from acoustic wave observations. This study proposes a solution that is derived from the multidimensional Marchenko equation, to learn about the acoustic source distribution inside a volume, given a set of observations outside...

journal article 2017

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Accounting for free-surface multiples in Marchenko imaging

Singh, S. (author), Snieder, R (author), van der Neut, J.R. (author), Thorbecke, J.W. (author), Slob, E.C. (author), Wapenaar, C.P.A. (author)

Imagine placing a receiver at any location in the earth and recording the response at that location to sources on the surface. In such a world, we could place receivers around our reservoir to better image the reservoir and understand its properties. Realistically, this is not a feasible approach for understanding the subsurface. We have...

journal article 2017

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On the role of multiples in Marchenko imaging

Wapenaar, C.P.A. (author), van der Neut, J.R. (author), Slob, E.C. (author)

journal article 2017

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Unified double- and single-sided homogeneous Green's function representations

Wapenaar, C.P.A. (author), van der Neut, J.R. (author), Slob, E.C. (author)

In wave theory, the homogeneous Green’s function consists of the impulse response to a point source, minus its time-reversal. It can be represented by a closed boundary integral. In many practical situations, the closed boundary integral needs to be approximated by an open boundary integral because the medium of interest is often accessible from...

journal article 2016

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Seismic reflection imaging, accounting for primary and multiple reflections

Wapenaar, C.P.A. (author), Van der Neut, J.R. (author), Thorbecke, J.W. (author), Broggini, F. (author), Slob, E.C. (author), Snieder, R. (author)

journal article 2015