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Reinicke, Christian (author), Dukalski, Marcin (author), Wapenaar, C.P.A. (author)
Minimum-phase properties are well-understood for scalar functions where they can be used as physical constraint for phase reconstruction. Existing scalar applications of the latter in geophysics include, for example the reconstruction of transmission from acoustic reflection data, or multiple elimination via the augmented acoustic Marchenko...
journal article 2023
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van IJsseldijk, J.E. (author), van der Neut, J.R. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author)
Geophysical monitoring of subsurface reservoirs relies on detecting small changes in the seismic response between a baseline and monitor study. However, internal multiples, related to the over- and underburden, can obstruct the view of the target response, hence complicating the time-lapse analysis. To retrieve a response that is free from...
journal article 2023
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Hartstra, I.E. (author), Wapenaar, C.P.A. (author)
Previous studies indicate that scattering may pose a trade-off for the performance of seismic interferometry (SI) applications for retrieving body-wave reflections of a target reflector. While it has been demonstrated that a higher scattering strength of the overburden improves the Green's function estimated by cross-correlation SI, other...
journal article 2023
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Shoja, Aydin (author), van der Neut, J.R. (author), Wapenaar, C.P.A. (author)
Least-squares reverse-time migration (LSRTM) is a method that seismologists utilize to compute a high-resolution subsurface image. Nevertheless, LSRTM is a computationally demanding problem. One way to reduce the computational costs of the LSRTM is to choose a small region of interest (ROI) and compute the image of that region. However, finding...
journal article 2023
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Wapenaar, C.P.A. (author)
For the elastodynamic wave equation discussed in Appendix A.4 in Ref. 1, the expressions for matrices ∼L 6 1 and ∼L 6 2 in Eqs. (A32) and (A33) must be multiplied by 61. In other words, the signs of ∼L _ <sub>1</sub>and ∼L _ <sub>2</sub>have to be changed, whereas the signs of ∼L 1 and ∼L 2 remain unchanged. With these corrections, matrix ∼L ...
journal article 2023
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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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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 IJsseldijk, J.E. (author), Hajibeygi, H. (author), Wapenaar, C.P.A. (author)
Reservoir simulations for subsurface processes play an important role in successful deployment of geoscience applications such as geothermal energy extraction and geo-storage of fluids. These simulations provide time-lapse dynamics of the coupled poromechanical processes within the reservoir and its over-, under-, and side-burden environments...
journal article 2023
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Wapenaar, C.P.A. (author), Dukalski, Marcin (author), Reinicke, Christian (author), Snieder, Roel (author)
Many seismic imaging methods use wavefield extrapolation operators to redatum sources and receivers from the surface into the subsurface. We discuss wavefield extrapolation operators that account for internal multiple reflections, in particular propagator matrices, transfer matrices and Marchenko focusing functions. A propagator matrix is a...
journal article 2023
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Wapenaar, C.P.A. (author)
Classical acoustic wave-field representations consist of volume and boundary integrals, of which the integrands contain specific combinations of Green's functions, source distributions, and wave fields. Using a unified matrix-vector wave equation for different wave phenomena, these representations can be reformulated in terms of Green's matrices...
journal article 2022
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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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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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Shoja, Aydin (author), van der Neut, J.R. (author), Wapenaar, C.P.A. (author)
Geophysicists have widely used least-squares reverse-time migration (LSRTM) to obtain high-resolution images of the subsurface. However, LSRTM is computationally expensive and it can suffer from multiple reflections. Recently, a target-oriented approach to LSRTM has been proposed, which focuses the wavefield above the target of interest....
journal article 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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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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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), 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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