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Van der Neut, J. (author), Tatanova, M. (author), Thorbecke, J. (author), Slob, E. (author), Wapenaar, K. (author)
With controlled-source seismic interferometry we aim to redatum sources to downhole receiver locations without requiring a velocity model. Interferometry is generally based on a source integral over cross-correlation (CC) pairs of full, perturbed (timegated), or decomposed wavefields. We provide an overview of ghosts, multiples, and spatial...
journal article
document
Hunziker, J.W. (author), Slob, E.C. (author), Wapenaar, C.P.A. (author)
In time-lapse controlled-source electromagnetics, it is crucial that the source and the receivers are positioned at exactly the same location at all times of measurement. We use interferometry by multidimensional deconvolution (MDD) to overcome problems in repeatability of the source location. Interferometry by MDD redatums the source to a...
journal article
document
Wapenaar, C.P.A. (author), Slob, E.C. (author), Snieder, R. (author)
It has been shown by many authors that the cross correlation of two recordings of a diffuse wave field at different receivers yields the Green’s function between these receivers. Recently the theory has been extended for situations where time-reversal invariance does not hold (e.g., in attenuating media) and where source-receiver reciprocity...
journal article 2006
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Slob, E.C. (author), Wapenaar, C.P.A. (author)
It is shown that the electromagnetic Green's functions of any linear medium with arbitrary heterogeneity can be obtained from the cross?correlation, or the cross?convolution, of two recordings at different receiver locations in an open system. Existing representations are known for cross?correlations where time?reversal invariance is exploited...
journal article 2007
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Toxopeus, G. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author), Petersen, S. (author), Slob, E.C. (author), Fokkema, J.T. (author)
The simulation of migrated and inverted data is hampered by the high computational cost of generating 3D synthetic data, followed by processes of migration and inversion. For example, simulating the migrated seismic signature of subtle stratigraphic traps demands the expensive exercise of 3D forward modeling, followed by 3D migration of the...
journal article 2008
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Wapenaar, C.P.A. (author), Slob, E.C. (author), Snieder, R. (author)
We have analyzed the far-field approximation of the Green's function representation for seismic interferometry. By writing each of the Green's functions involved in the correlation process as a superposition of a direct wave and a scattered wave, the Green's function representation is rewritten as a superposition of four terms. When the...
journal article 2010
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Wapenaar, C.P.A. (author), Slob, E.C. (author), Snieder, R. (author), Curtis, A. (author)
In the 1990s, the method of time-reversed acoustics was developed. This method exploits the fact that the acoustic wave equation for a lossless medium is invariant for time reversal. When ultrasonic responses recorded by piezoelectric transducers are reversed in time and fed simultaneously as source signals to the transducers, they focus at the...
journal article 2010
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Van der Neut, J.R. (author), Tatanova, M. (author), Thorbecke, J.W. (author), Slob, E.C. (author), Wapenaar, C.P.A. (author)
With controlled-source seismic interferometry we aim to redatum sources to downhole receiver locations without requiring a velocity model. Interferometry is generally based on a source integral over cross-correlation (CC) pairs of full, perturbed (time-gated), or decomposed wavefields. We provide an overview of ghosts, multiples, and spatial...
journal article 2011
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Van der Neut, J.R. (author), Thorbecke, J.W. (author), Mehta, K. (author), Slob, E.C. (author), Wapenaar, C.P.A. (author)
Various researchers have shown that accurate redatuming of controlled seismic sources to downhole receiver locations can be achieved without requiring a velocity model. By placing receivers in a horizontal or deviated well and turning them into virtual sources, accurate images can be obtained even below a complex near-subsurface. Examples...
journal article 2011
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Hunziker, J.W. (author), Slob, E.C. (author), Fan, Y. (author), Snieder, R. (author), Wapenaar, C.P.A. (author)
Interferometry by multidimensional deconvolution applied to Controlled-Source Electromagnetic data replaces the medium above the receivers by a homogeneous halfspace, suppresses the direct field and redatums the source positions to the receiver locations. In that sense, the airwave and any other interactions of the signal with the air-water...
conference paper 2012
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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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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), 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)
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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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
document
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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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)
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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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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