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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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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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Staring, M. (author), Wapenaar, C.P.A. (author)
We apply Marchenko redatuming using an adaptive double-focusing method to 3D field data of the Santos basin, Brazil. This method was already successfully applied to 2D field data and we now study the acquisition geometry and preprocessing requirements in 3D. We start from 3D synthetic data modeled on a dense grid of colocated sources and...
conference paper 2019
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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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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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Hartstra, I.E. (author), Almagro Vidal, C. (author), Wapenaar, C.P.A. (author)
Seismic interferometry (SI) presents a set of inexpensive and noninvasive methods that can be applied to any array at the surface to retrieve virtual body-wave reflection responses from earthquake recordings. Conventional SI by cross-correlation requires recordings of wavefields in lossless media generated by a smooth continuous distribution of...
conference paper 2016
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Holicki, M.E. (author), Wapenaar, C.P.A. (author), Drijkoningen, G.G. (author)
We propose a novel acoustic decomposition operator for time slices, loosely based on conventional surface decomposition operators. The proposed operators hold for constant velocity models and require two 2D Fourier Transforms (one forward, one backward) per decomposed time slice per decomposition direction. We then demonstrate the capabilities...
conference paper 2016
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Liu, Yi (author), Arntsen, B (author), Landrö, M (author), van der Neut, J.R. (author), Wapenaar, C.P.A. (author)
Understanding seismic changes in the subsurface is important for reservoir management and health, safety and environmental (HSE) issues. Typically the changes are interpreted based on the time shifts in seismic time-lapse (4D) data, where sources are at the surface and receivers are either at the surface or in a borehole. With these types of...
conference paper 2016
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Staring, M. (author), Pereira, R (author), Douma, H (author), van der Neut, J.R. (author), Wapenaar, C.P.A. (author)
We present an adaptive double-focusing method for applying source-receiver Marchenko redatuming to field data. Receiver redatuming is achieved by a first focusing step, where the coupled Marchenko equations are iteratively solved for the oneway Green’s functions. Next, source redatuming is typically performed by a multi-dimensional deconvolution...
conference paper 2017
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Barrera Pacheco, D.F. (author), Schleicher, J. (author), van der Neut, J.R. (author), Wapenaar, C.P.A. (author)
Seismic interferometry is a method to retrieve Green’s functions for sources (or receivers) where there are only receivers (or sources, respectively). This can be done by correlationor deconvolution-based methods. In this work we present a<br/>new approach to reposition the seismic array from the earth’s surface to an arbitrary datum at depth...
conference paper 2017
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Slob, E.C. (author), Zhang, L. (author), Wapenaar, C.P.A. (author)
A modified implementation of Marchenko redatuming leads to a filter that removes internal multiples from reflection data. It produces local reflectivity at two-way travel time. The method creates new primary reflections resulting from emitted events that eliminate internal multiples. We call these non-physical<br/>primaries and their presence is...
conference paper 2017
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Brackenhoff, J.A. (author), van der Neut, J.R. (author), Wapenaar, C.P.A. (author)
The Marchenko equation can be used to retrieve the Green’s function at depth as a full function or decomposed into its upand downgoing parts. We show that the equation can be rewritten to create a decomposition scheme that can decompose a full wavefield, that was recorded at depth, into its up- and downgoing parts. We show that this can be done...
conference paper 2017
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Wapenaar, C.P.A. (author), Slob, E.C. (author)
In a time-lapse experiment, changes in a reservoir cause changes in the reflection response. We discuss a method which predicts these changes from the baseline survey and a model of the changed reservoir. This method, which takes all multiple<br/>scattering into account, is significantly more efficient than modeling the response of the entire...
conference paper 2017
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Hartstra, I.E. (author), Wapenaar, C.P.A. (author)
We discuss a method to interferometrically retrieve the body wave reflection response from local high-frequency scattering coda wave fields with the purpose to obtain an input dataset suitable for the application of advanced exploration-type imaging methods
conference paper 2015
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Wapenaar, C.P.A. (author), van IJsseldijk, J.E. (author)
Time-lapse seismic monitoring aims at resolving changes in a producing reservoir from changes in the reflection response. When the changes in the reservoir are very small, the changes in the seismic response can become too small to be reliably detected. In theory, multiple reflections can be used to improve the detectability of traveltime...
conference paper 2020
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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 subsurface, accounting for all orders of multiples. The method is based on two integral representations for focusing and Green’s functions. In discretized form these integrals are represented by finite summations over the acquisition geometry. Consequently, the method...
conference paper 2020
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Shoja, Aydin (author), Meles, G.A. (author), Wapenaar, C.P.A. (author)
The Hessian matrix plays an important role in correct interpretation of the multiple scattered wave fields inside the FWI frame work. Due to the high computational costs, the computation of the Hessian matrix is not feasible. Consequently, FWI produces overburden related artifacts inside the target zone model, due to the lack of the exact...
conference paper 2020
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