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Wapenaar, C.P.A. (author), Brackenhoff, J. (author), De Ridder, S. (author), Slob, E.C. (author), Snieder, R. (author)
Green’s functions and propagator matrices are both solutions of the wave equation, but whereas Green’s functions obey a causality condition in time (G = 0 for t < 0), propagator matrices obey a boundary condition in space. Marchenko-type focusing functions focus a wave field in space at zero time. We discuss the mutual relations between Green...
conference paper 2023
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van IJsseldijk, J.E. (author), Brackenhoff, Joeri (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author)
The data-driven Marchenko method is able to redatum wavefields to arbitrary locations in the subsurface, and can, therefore, be used to isolate zones of specific interest. This creates a new reflection response of the target zone without interference from over- or underburden reflectors. Consequently, the method is well suited to obtain a...
journal article 2023
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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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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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van der Neut, J.R. (author), Brackenhoff, J. (author), Meles, Giovanni Angelo (author), Slob, E.C. (author), Wapenaar, C.P.A. (author)
Green’s functions in an unknown elastic layered medium can be retrieved from single-sided reflection data by solving a Marchenko equation. This methodology requires a priori knowledge of all forward-scattered (non-converted and converted) waveforms. Moreover, the medium should satisfy stringent monotonicity conditions, which are often not met in...
conference paper 2022
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Brackenhoff, J.A. (author), Thorbecke, J.W. (author), Meles, G.A. (author), Koehne, Victor (author), Barrera, Diego (author), Wapenaar, C.P.A. (author)
We implement the 3D Marchenko equations to retrieve responses to virtual sources inside the subsurface. For this, we require reflection data at the surface of the Earth that contain no free-surface multiples and are densely sampled in space. The required 3D reflection data volume is very large and solving the Marchenko equations requires a...
journal article 2022
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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), 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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Wapenaar, C.P.A. (author), Staring, M. (author), Brackenhoff, J.A. (author), Zhang, L. (author), Thorbecke, J.W. (author), Slob, E.C. (author)
Since the introduction of the Marchenko method in geophysics, many variants have been developed. Using a compact unified notation, we review redatuming by multidimensional deconvolution and by double focusing, virtual seismology, double dereverberation and transmission-compensated Marchenko multiple elimination, and discuss the underlying...
conference paper 2020
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Brackenhoff, J.A. (author), van IJsseldijk, J.E. (author), Wapenaar, C.P.A. (author)
We consider reflection data that have been subsampled by 70% and use Point-Spread-Functions to reconstruct the original data. The subsampled, original and reconstructed reflection data are used to image the medium of interest with the Marchenko method. The image obtained using the subsampled data shows artifacts caused by internal multiples,...
conference paper 2020
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Alfaraj, H.S.A. (author), Brackenhoff, J.A. (author), Wapenaar, C.P.A. (author)
When reflection images are studied, often only the zero-offset reflectivity is considered, however, taking into account the angle-dependent reflectivity can add additional information about the subsurface. This additional information can be used to extract the properties of the subsurface using amplitude variation with offset (AVO) analysis....
conference paper 2020
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Brackenhoff, J.A. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author)
abstract 2020
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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
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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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Wapenaar, C.P.A. (author), Brackenhoff, J.A. (author), Thorbecke, J.W. (author)
The earthquake seismology and seismic exploration communities have developed a variety of seismic imaging methods for passive- and active-source data. Despite the seemingly different approaches and underlying principles, many of those methods are based in some way or another on Green's theorem. The aim of this paper is to discuss a variety of...
journal article 2019
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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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Brackenhoff, J.A. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author)
We aim to monitor and characterize signals in the subsurface by combining these passive signals with recorded reflection data at the surface of the Earth. To achieve this, we propose a method to create virtual receivers from reflection data using the Marchenko method. By applying homogeneous Green's function retrieval, these virtual receivers...
journal article 2019
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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
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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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