Searched for: collection%253Air
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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)
Marchenko imaging is a novel imaging technique that is capable to retrieve images from single-sided reflection measurements free of artefacts related to internal multiples (e.g. Behura et al., 2014; Broggini et al., 2012). An essential ingredient of Marchenko imaging is the so-called focusing function which can<br/>be retrieved from reflection...
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), van der Neut, J.R. (author), Wapenaar, C.P.A. (author)
We have derived an improved reverse time migration (RTM) scheme to image the medium without artifacts arising from internal multiple reflections. This is based on a revised implementation of Marchenko redatuming using a new time-truncation operator. Because of the new truncation operator, we can use the time-reversed version of the standard...
journal article 2018
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Slob, E.C. (author), Wapenaar, C.P.A. (author), Treitel, Sven (author)
We derive a fast acoustic inversion method for a piecewise homogeneous horizontally layered medium. The method obtains medium parameters from the reflection response. The method can be implemented to obtain the parameters on either side of a reflector at an arbitrary depth. Three processing steps lead to the inversion result. First, we solve a...
conference paper 2018
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Alkhimenkov, Y. (author), 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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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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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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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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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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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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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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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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Wapenaar, C.P.A. (author), van der Neut, J.R. (author), Slob, E.C. (author)
journal article 2017
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Slob, E.C. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author)
We present a scheme for Marchenko imaging in a dissipative heterogeneous medium. The scheme requires measured reflection and transmission data at two sides of the dissipative medium. The effectual medium is the same as the dissipative medium, but with negative dissipation. We show how the measured double-sided data can be combined to obtain the...
conference paper 2016
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Wapenaar, C.P.A. (author), van der Neut, J.R. (author), Thorbecke, J.W. (author), Slob, E.C. (author), Singh, Satyan (author)
The homogeneous Green’s function (i.e., the Green’s function and its time-reversed counterpart) plays an important role in optical, acoustic and seismic holography, in inverse scattering methods, in the field of time-reversal acoustics, in reversetime migration and in seismic interferometry. Starting with the classical closed-boundary...
conference paper 2016
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Wapenaar, C.P.A. (author), van der Neut, J.R. (author), Thorbecke, J.W. (author), Slob, E.C. (author), Snieder, R (author)
abstract 2016
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Wapenaar, C.P.A. (author), van der Neut, J.R. (author), Slob, E.C. (author)
In wave theory, the homogeneous Green’s function consists of the impulse response to a point source, minus its time-reversal. It can be represented by a closed boundary integral. In many practical situations, the closed boundary integral needs to be approximated by an open boundary integral because the medium of interest is often accessible from...
journal article 2016
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Zhang, L. (author), Slob, E.C. (author), van der Neut, J.R. (author), Staring, M. (author), Wapenaar, C.P.A. (author)
We present a one-dimensional lossless scheme to compute an image of a dissipative medium from two single-sided reflection responses. One reflection response is measured at or above the top reflector of a dissipative medium and the other reflection response is computed as if measured at or above the top reflector of a medium with negative...
conference paper 2016
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