Searched for: author%3A%22Wapenaar%2C+C.P.A.%22
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Shoja, Aydin (author), van der Neut, J.R. (author), Wapenaar, C.P.A. (author)
Recently, the focus of reflection seismologists has shifted to applications where a high-resolution image of the subsurface is required. Least-Squares Reverse-Time Migration (LSRTM) is a common tool used to compute such images. Still, its high computational costs have led seismologists to use target-oriented LSRTM for imaging only a small target...
journal article 2024
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Thorbecke, J.W. (author), Almobarak, Mohammed (author), van IJsseldijk, J.E. (author), Brackenhoff, Joeri (author), Meles, Giovanni (author), Wapenaar, C.P.A. (author)
The Marchenko algorithm can suppress the disturbing effects of internal multiples that are present in seismic reflection data. To achieve this, a set of coupled equations with four unknowns is solved. These coupled equations are separated into a set of two equations with two unknowns using a time window. The two unknown focusing functions can...
journal article 2024
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Shirmohammadi, F. (author), Draganov, D.S. (author), van IJsseldijk, J.E. (author), Ghose, R. (author), Thorbecke, J.W. (author), Verschuur, D.J. (author), Wapenaar, C.P.A. (author)
The Marchenko method is capable of estimating Green’s functions between the surface of the Earth and arbitrary locations in the subsurface. These Green’s functions are used to redatum wavefields to a deeper level in the subsurface. The Marchenko method enables the isolation of the response of a specific layer or package of layers, free from the...
conference paper 2024
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Wapenaar, C.P.A. (author), van IJsseldijk, J.E. (author)
Coda-wave interferometry employs the sensitivity of multiply scattered waves to detect minute changes of the propagation velocity. In most applications the underlying assumption is that the velocity changes take place approximately uniformly in a large region. Time-lapse seismic reservoir monitoring, on the other hand, aims to infer local time...
conference paper 2024
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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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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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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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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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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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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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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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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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Shoja, Aydin (author), van der Neut, J.R. (author), Wapenaar, C.P.A. (author)
Least-squares reverse time migration (LSRTM) is a common imaging technique that geophysicists have been using to obtain high-resolution images. Nevertheless, the high computational cost shifted the focus of researchers to the target-oriented approach. In this approach, by limiting the computational grid to a relatively smaller region, the...
conference paper 2022
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Meles, G.A. (author), Reinicke, Christian (author), Dukalski, M (author), Wapenaar, C.P.A. (author)
Marchenko redatuming retrieves Green’s functions inside an unknown medium, by solving a set of coupled Marchenko equations, which are derived from an under-determined system of equation and two temporal truncations. To constrain the problem, two assumptions are made, which hold reasonably well for acoustic, but not for elastodynamic waves. First...
conference paper 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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Dukalski, M (author), Reinicke, Christian (author), Wapenaar, C.P.A. (author)
The presence of evanescent modes and their impact on the Marchenko method has been until very recently a topic that received little attention. In this contribution we link the concept of the transfer matrix to the fields usually associated with the Marchenko method. Using that formalism, we introduce the concept of a path reversal - a...
conference paper 2022
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Al Hasani, M.M.K. (author), Drijkoningen, G.G. (author), Wapenaar, C.P.A. (author)
In a surface-seismic setting, Distributed Acoustic Sensing (DAS) is still not a widely adopted method for near-surface characterisation, especially for reflection seismic imaging, despite the dense spatial sampling it provides over long distances. This is mainly due to the decreased broadside sensitivity that DAS suffers from when buried...
conference paper 2022
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Shirmohammadi, F. (author), Draganov, D.S. (author), Ras, Paul (author), Wapenaar, C.P.A. (author)
Seismic interferometry (SI) is a method that retrieves new seismic traces from the cross-correlation of existing traces, where one of the receivers acts as a virtual seismic source whose response is retrieved at other receivers. When using sources only at the surface, and so-called one-sided illumination of the receivers occurs, not only desired...
abstract 2022
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