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Staring, M. (author), Wapenaar, C.P.A. (author)
Internal multiples can create severe artefacts in seismic imaging, especially when our zone of interest is overlain by a complex overburden. These artefacts can mask structures, which has a strong effect on the interpretation of the image. Therefore, multiple prediction and removal is of significant importance for correct imaging and...
conference paper 2018
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Brackenhoff, J.A. (author), Slob, E.C. (author), Wapenaar, C.P.A. (author)
Marchenko Imaging is a new technology in geophysics, which enables us to retrieve Green's functions at any point in the subsurface having only reflection data. One of the assumptions of the Marchenko method is that the medium is lossless. One way to circumvent this assumption is to find a compensation parameter for the lossy reflection series so...
conference paper 2018
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Wapenaar, C.P.A. (author), Brackenhoff, J.A. (author), Staring, M. (author), Thorbecke, J.W. (author), Slob, E.C. (author)
Recent developments in exploration seismology have enabled the creation of virtual sources and/or virtual receivers in the subsurface from reflection measurements at the earth's surface. Unlike in seismic interferometry, no physical instrument (receiver or source) is needed at the position of the virtual source or receiver. Moreover, no detailed...
conference paper 2018
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Zhang, L. (author), Slob, E.C. (author), Wapenaar, C.P.A. (author), van der Neut, J.R. (author)
A revised Marchenko scheme that avoids the need to compute the Green’s function is presented for artefact-free image of the subsurface with single-sided reflection response as input. The initial downgoing Green’s function which can be modelled from a macro model is needed for solving the revised Marchenko equations instead of its inverse. The...
conference paper 2018
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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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Liu, Y. (author), Landrø, Martin (author), Arntsen, Børge (author), van der Neut, J.R. (author), Wapenaar, C.P.A. (author)
For a robust way of estimating time shifts near horizontal boreholes, we have developed a method for separating the reflection responses above and below a horizontal borehole. Together with the surface reflection data, the method uses the direct arrivals from borehole data in the Marchenko method. The first step is to retrieve the focusing...
journal article 2017
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Slob, E.C. (author), Wapenaar, C.P.A. (author)
We present a three-dimensional scheme that can be used to compute the electromagnetic impulse response between any two subsurface points from surface reflection data measured at a single surface of a lossless medium. The scheme first computes a virtual vertical radar profile using the Marchenko scheme from which focusing wavefields are...
conference paper 2017
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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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Wapenaar, C.P.A. (author)
journal article 2017
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Ruigrok, E.N. (author), Gibbons, Steven (author), Wapenaar, C.P.A. (author)
An areal distribution of sensors can be used for estimating the direction of incoming waves through beamforming. Beamforming may be implemented as a phase-shifting and stacking of data recorded on the different sensors (i.e., conventional beamforming). Alternatively, beamforming can be applied to cross-correlations between the waveforms on...
journal article 2017
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Hartstra, I.E. (author), Almagro Vidal, C. (author), Wapenaar, C.P.A. (author)
Our objective is to complement lithospheric seismic tomography with an interferometric method to retrieve high-resolution reflectivity images from local earthquake recordings. The disadvantage of using local earthquakes for the retrieval of reflected body-waves is their usual sparse distribution. We propose an alternative formulation of passive...
journal article 2017
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Evers, L.G. (author), Wapenaar, C.P.A. (author), Heaney, KD (author), Snellen, M. (author)
The propagation of acoustic waves in the ocean strongly depends on the temperature. Lowfrequency acoustic waves can penetrate the ocean down to depths where few in situ measurements are available. It is therefore attractive to obtain a measure of the deep ocean temperature from acoustic waves. The latter is especially true if the ambient...
journal article 2017
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Liu, Y. (author), Arntsen, B (author), van der Neut, J.R. (author), Wapenaar, C.P.A. (author)
A standard procedure in processing vertical seismic profile (VSP) data is the separation of up-and downgoing wavefields. We show that the up-down wavefields in boreholes can be reconstructed using only singlecomponent borehole data, given that a full set of surface reflection data is also available. No medium parameters are required. The method...
conference paper 2017
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Dokter, E. (author), Meles, G.A. (author), Curtis, A (author), Wapenaar, C.P.A. (author)
A number of seismic processing methods, including velocity analysis (Sheriff and Geldart, 1999), make the assumption that recorded waves are primaries - that they have scattered only once (the Born approximation). Multiples then represent a source of coherent noise and must be suppressed to avoid artefacts. There are different approaches to...
conference paper 2017
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Wapenaar, C.P.A. (author), van der Neut, J.R. (author), Slob, E.C. (author)
journal article 2017
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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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Slob, E.C. (author), Wapenaar, C.P.A. (author)
The theory of data-driven true amplitude migration is presented for multicomponent marine seismic data. The Marchenko scheme is adapted to account for the ghost, free surface and internal multiple effects and works without the need to know the source wavelet. A true amplitude image is formed from the obtained focusing functions without ghost...
conference paper 2017
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Holicki, M.E. (author), Drijkoningen, G.G. (author), Wapenaar, C.P.A. (author)
We propose a novel directional decomposition operator for wavefield snapshots in heterogeneous-velocity media. The proposed operator demonstrates the link between the amplitude of pressure and particlevelocity plane waves in the wavenumber domain. The proposed operator requires two spatial Fourier transforms (one forward and one backward) per...
conference paper 2017
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Wapenaar, C.P.A. (author), van der Neut, J.R. (author), Slob, E.C. (author)
The question whether multiples are signal or noise is subject of ongoing debate. In this paper we consider correlation and deconvolution imaging methods and analyse to what extent multiples contribute to the image in these methods. Our starting point is the assumption that at a specific depth level the full downgoing and upgoing fields (both...
conference paper 2017
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Staring, M. (author), Grobbe, N. (author), van der Neut, J.R. (author), Wapenaar, C.P.A. (author)
We compare the coupled Marchenko equations without free-surface multiples to the coupled Marchenko equations including free-surface multiples. When using the conventional method of iterative substitution to solve these equations, a difference in convergence behaviour is observed, suggesting that there is a fundamental difference in the...
conference paper 2017
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