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Wapenaar, C.P.A. (author), Thorbecke, J.W. (author), Van der Neut, J.R. (author), Broggini, F. (author), Slob, E.C. (author), Snieder, R. (author)
The methodology of Green’s function retrieval by cross-correlation has led to many interesting applications for passive and controlled-source acoustic measurements. In all applications, a virtual source is created at the position of a receiver. Here a method is discussed for Green’s function retrieval from controlled-source reflection data,...
journal article 2014
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Slob, E.C. (author), Wapenaar, C.P.A. (author)
Two wavefields can be retrieved from the measured reflection response at the surface. One is the Green’s function at a chosen virtual receiver depth level in a layered model generated by a source at the surface. The other wavefield consists of the upgoing and downgoing parts of a wavefield that focuses at the virtual receiver depth level. From...
conference paper 2014
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Slob, E.C. (author), Wapenaar, C.P.A. (author), Broggini, F. (author), Snieder, R. (author)
We present an imaging method that creates a map of reflection coefficients in correct one-way time with no contamination from internal multiples using purely a filtering approach. The filter is computed from the measured reflection response and does not require a background model. We demonstrate that the filter is a focusing wavefield that...
journal article 2014
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Slob, E.C. (author), Wapenaar, C.P.A. (author)
Recently a new theory has been developed to retrieve a wavefield generated by a source on the surface and recorded at a point in the subsurface without the need for a receiver at that subsurface location. The scheme is presented for three-dimensional wavefields. It decomposes the electromagnetic field in up- and downgoing electric fields and in...
journal article 2013
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Grobbe, N. (author), Slob, E.C. (author)
We have developed an analytically based, energy fluxnormalized numerical modeling code (ESSEMOD), capable of modeling the wave propagation of all existing ElectroSeismic and SeismoElectric source-receiver combinations in horizontally layered configurations. We compare the results of several of these modeled source-receiver combinations in a...
journal article 2013
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Van der Neut, J. (author), Slob, E.C. (author), Wapenaar, C.P.A. (author), Throbecke, J.W. (author), Snieder, R. (author), Broggini, F. (author)
Recently, an iterative scheme has been introduced to retrieve the down- and upgoing Green's functions at an arbitrary level ?F inside an acoustic medium as if there were a source at the surface. This scheme requires as input the reflection response acquired at the surface and the direct arrival of the transmission response from the surface to...
journal article 2013
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Wapenaar, C.P.A. (author), Slob, E.C. (author), Van der Neut, J. (author), Thorbecke, J.W. (author), Broggini, F. (author), Snieder, R. (author)
In recent work we showed with heuristic arguments that the Green's response to a virtual source in the subsurface can be obtained from reflection data at the surface. This method is called “Green's function retrieval beyond seismic interferometry”, because, unlike in seismic interferometry, no receiver is needed at the position of the virtual...
journal article 2013
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Van Dalen, K.N. (author), Slob, E.C. (author), Schoemaker, C. (author)
journal article 2013
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Ponziani, M. (author), Slob, E.C. (author), Luthi, S.M. (author), Bloemenkamp, R.F. (author), Le Nir, I. (author)
The Formation MicroImager (mark of Schlumberger) is an electric imaging tool that produces electrical scans of the borehole walls. These measurements provide useful information on the fracture aperture of naturally fractured reservoirs. In this paper, we present a laboratory set-up that was realized to perform controlled experiments on fractured...
conference paper 2013
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Hunziker, J.W. (author), Slob, E.C. (author), Fan, Y. (author), Snieder, R. (author), Wapenaar, C.P.A. (author)
We use interferometry by multidimensional deconvolution in combination with synthetic aperture sources in 3D to suppress the airwave and the direct field, and to decrease source uncertainty in marine Controlled-Source electromagnetics. We show with this numerical study that the method works for very large receiver spacing distances, even though...
conference paper 2013
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Wapenaar, C.P.A. (author), Slob, E.C. (author), Broggini, F. (author), Snieder, R. (author), Thorbecke, J.W. (author), Van der Neut, J.R. (author)
Recently we introduced a new approach for retrieving the Green's response to a virtual source in the subsurface from reflection data at the surface. Unlike in seismic interferometry, no receiver is needed at the position of the virtual source. Here we present the theory behind this new method. First we introduce the Green's function G and a so...
conference paper 2013
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Hunziker, J.W. (author), Slob, E.C. (author), Fan, Y. (author), Snieder, R. (author), Wapenaar, C.P.A. (author)
With interferometry applied to controlled-source electromagnetic data, the direct field and the airwave and all other effects related to the air-water interface can be suppressed in a data-driven way. Interferometry allows for retreival of the scattered field Green’s function of the subsurface or, in other words, the subsurface reflection...
journal article 2013
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Wapenaar, C.P.A. (author), Broggini, F. (author), Slob, E.C. (author), Snieder, R. (author)
The one-dimensional Marchenko equation forms the basis for inverse scattering problems in which the scattering object is accessible from one side only. Here we derive a three-dimensional (3D) Marchenko equation which relates the single-sided reflection response of a 3D inhomogeneous medium to a field inside the medium. We show that this equation...
journal article 2013
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Grobbe, N. (author), Schoemaker, F.C. (author), Schakel, M.D. (author), De Ridder, S.A.L. (author), Slob, E.C. (author), Smeulders, D.M.J. (author)
conference paper 2012
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Ponziani, M. (author), Slob, E.C. (author), Vanhala, H. (author), Tillard, D.J.M. (author)
Organic layers are heterogeneous in space and their composition changes over time. This poses challenges to ecohydrologists, subsurface hydrologists and ground engineers in characterizing subsurface peat structures and predicting their behaviour over time. Peat deposits can be characterized by performing electrical surveys, provided that the...
journal article 2012
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Lambot, S. (author), Andre, F. (author), Slob, E.C. (author), Vereecken, H. (author)
journal article 2012
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Grobbe, N. (author), Thorbecke, J.W. (author), Slob, E.C. (author)
conference paper 2012
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Slob, C. (author), Mohammadi, S. (author), Geraedts, R.P. (author)
‘Perfection means something is complete and stands still and what stands still doesn’t change or evolve and is automatically dead. Everything in the universe changes, evolution implies that the creation is not complete hence the possibility of evolving’ (Osho, 1985). Our society and economy are constantly changing. Hence the demands and wishes...
conference paper 2012
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Moradi Tehrani, A. (author), Slob, E.C. (author), Mulder, W. (author)
Frequency-to-time transformations are of interest to controlled-source electromagnetic methods when time-domain data are inverted for a subsurface resistivity model by numerical frequency-domain modeling at a selected, small number of frequencies whereas the data misfit is determined in the time domain. We propose an efficient, Prony-type method...
journal article 2012
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Slob, M. (author), Ligtvoet, W. (author), Kuiper, R. (author), Van Egmand, P. (author)
Rijn-Schelde Delta: gedeelde langetermijnvisie noodzakelijk voor goed afgestemde investeringsbeslissingen Welke economische perspectieven zijn er binnen de Rijn-Schelde Delta? Is de A4 te beschouwen als een economische ontwikkelingszone voor de Delta of alleen als transportas? Hoe om te gaan met veiligheid en met zoet- en zoutwater in de Delta?...
report 2012
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