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Yang, B. (author), Slob, E.C. (author)
We present a data driven method of full waveform inversion in one dimension. This means that the inversion is carried out as a sequence of processing steps. The first step is known as Marchenko redatuming. In this step we retrieve focusing functions from the measured data. In the second step we isolate the last event in the focusing function to...
conference paper 2018
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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)
We retrieve transmission compensated subsurface primary reflections from the reflection response measured at the surface. This is achieved by filtering the reflection response. The application of this scheme does not require model information. In this process, the reflection response is convolved and correlated with itself. The result after each...
conference paper 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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Slob, E.C. (author), Ziolkowski, A. (author)
We argue that in a half space model with a single layer, the electric field impulse response at different offsets can be understood physically. Diffusive fields travel along paths like wavefields but are not localised in time. Each event that is measured comes from a path with the least attenuation, which corresponds to early arrival. The most...
conference paper 2018
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Zhang, L. (author), Slob, E.C. (author)
Iterative substitution of the Marchenko equation has been introduced recently to integrate internal multiple reflection in the seismic and electromagnetic imaging process. In the so-called Marchenko imaging, solving the Marchenko equation at each imaging point is required to meet this objective. It makes the scheme seriously expensive....
conference paper 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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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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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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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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Prins, M. (author), Mohammadi, S. (author), Slob, N. (author)
Recently the Circular Economy (CE) concept has gained momentum in the Netherlands, propounding that environmental impact reduction can provide a significant positive economical impulse. The government, larger parts of the industry as a whole, as well as the construction industry, has warmly received this approach. At first sight the CE concept...
conference paper 2015
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Wapenaar, C.P.A. (author), Slob, E.C. (author)
Building on acoustic autofocusing in 1D media, we previously proposed acoustic Marchenko imaging for 1D and 3D media. Recently, the first steps have been set towards extending the single-sided Marchenko method to the elastodynamic situation. Here we discuss the extension of single-sided Marchenko focusing, Green's function retrieval and imaging...
conference paper 2015
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Maas, P.J. (author), Grobbe, N. (author), Slob, E.C. (author), Mulder, W.A. (author)
For multi-parameter problems, such as the seismoelectric system, sensitivity analysis through resolution functions is a low-cost, fast method of determining whether measured fields are sensitive to certain subsurface parameters. We define a seismoelectric resolution function for the inversion of a bulk density perturbation. The synthetic data...
conference paper 2015
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