Searched for: author%3A%22Wapenaar%2C+C.P.A.%22
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Liu, Y. (author), Wapenaar, C.P.A. (author), Romdhane, A. (author)
Seismic interferometry (SI) is usually implemented by crosscorrelation (CC) to retrieve the impulse response between pairs of receiver positions. An alternative approach by multidimensional deconvolution (MDD) has been developed and shown in various studies the potential to suppress artifacts due to irregular source distribution and intrinsic...
conference paper 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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Van der Neut, J.R. (author), Wapenaar, C.P.A. (author), Thorbecke, J.W. (author), Vasconcelos, I. (author)
Complex overburdens can severely distort transmitted wavefields, posing serious challenges for seismic imaging. In Marchenko redatuming, we use an iterative scheme to estimate so-called focusing functions, which can be used to redatum seismic wavefields to a specified level below the major complexities in the subsurface. Unlike in conventional...
conference paper 2014
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Broggini, F. (author), Wapenaar, C.P.A. (author), Van der Neut, J.R. (author), Snieder, R. (author)
An iterative method is presented that allows one to retrieve the Green's function originating from a virtual source located inside a medium using reflection data measured only at the acquisition surface. In addition to the reflection response, an estimate of the travel times corresponding to the direct arrivals is required. However, no detailed...
journal article 2014
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Kasililar, A. (author), Harmankaya, U. (author), Wapenaar, C.P.A. (author), Draganov, D.S. (author)
The investigation of near-surface scatterers, such as cavities, tunnels, abandoned mine shafts, and buried objects, is important to mitigate geohazards and environmental hazards. By inversion of travel times of cross-correlated scattered waves, due to the incident Rayleigh waves, we estimate the location of a near-surface tunnel from seismic...
journal article 2013
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Kaslilar, A. (author), Harmankaya, U. (author), Wapenaar, C.P.A. (author), Draganov, D.S. (author)
The investigation of near-surface scatterers, such as cavities, tunnels, abandoned mine shafts, and buried objects, is important to mitigate geohazards and environmental hazards. By inversion of travel times of cross-correlated scattered waves, due to the incident Rayleigh waves, we estimate the location of a near-surface tunnel from seismic...
journal article 2013
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Van Dalen, K.N. (author), Wapenaar, C.P.A. (author), Halliday, D.F. (author)
Virtual-source surface wave responses can be retrieved using the crosscorrelation (CC) of wavefields observed at two receivers. Higher mode surface waves cannot be properly retrieved when there is a lack of subsurface sources that excite these wavefields, as is often the case. In this paper, we present a multidimensional-deconvolution (MDD)...
journal article 2013
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Thorbecke, J.W. (author), Van der Neut, J.R. (author), Wapenaar, C.P.A. (author)
Recent research showed that the Marchenko equation can be used to construct the Green’s function for a virtual source position in the subsurface. The method requires the reflection response at the surface and an estimate of the direct arrival of the wavefield, traveling from the virtual source location to the acquisition surface. In this paper,...
conference paper 2013
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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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Broggini, F. (author), Snieder, R. (author), Wapenaar, C.P.A. (author)
Standard imaging techniques rely on the single scattering assumption. This requires that the recorded data do not include internal multiples, i.e. waves bouncing multiple times between layers before reaching the receivers at the acquisition surface. When multiple reflections are present in the data, standard imaging algorithms incorrectly image...
journal article 2013
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Almagro Vidal, C. (author), Van der Neut, J. (author), Wapenaar, C.P.A. (author)
Changes in the subsurface can be imaged by subtracting seismic reflection data at two different states, one serving as the initial survey or base, and the second as the monitor survey. Conventionally, the reflection data are acquired by placing active seismic sources at the acquisition surface. Alternatively, these data can be acquired from...
journal article 2013
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Fricke, J.T. (author), El Allouche, N. (author), Simons, D.G. (author), Ruigrok, E.N. (author), Wapenaar, C.P.A. (author), Evers, L.G. (author)
The atmospheric wind and temperature can be estimated through the traveltimes of infrasound between pairs of receivers. The traveltimes can be obtained by infrasonic interferometry. In this study, the theory of infrasonic interferometry is verified and applied to modeled stratospherically refracted waves. Synthetic barograms are generated using...
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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Draganov, D.S. (author), Campman, X. (author), Thorbecke, J.W. (author), Verdel, A. (author), Wapenaar, C.P.A. (author)
The successful surface waves retrieval in solid?Earth seismology using long?time correlations and subsequent tomographic images of the crust have sparked interest in extraction of subsurface information from noise in the exploration seismology. Subsurface information in exploration seismology is usually derived from body?wave reflections >?1?Hz,...
journal article 2013
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Harmankaya, U. (author), Kaslilar, A. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author), Draganov, D.S. (author)
The investigation and detection of near-surface structures (such as cavities, caves, sinkholes, tunnels, mineshafts, buried objects, archeological ruins, water reservoir, etc.) is important to mitigate geo- and environmental hazards. In a former study, we suggested a method based on active-source seismic interferometry for locating the...
conference paper 2013
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Van der Neut, J.R. (author), Almagro Vidal, C. (author), Grobbe, N. (author), Wapenaar, C.P.A. (author)
We present a novel method to transform seismic data with sources at the surface and receivers above and below a selected target zone in the subsurface into virtual data with sources and receivers located at the initial receiver locations. The method is based on inverting a series of multidimensional equations of the convolution- and the...
conference paper 2013
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Broggini, F. (author), Snieder, R. (author), Wapenaar, C.P.A. (author), Thorbecke, J.W. (author)
Seismic interferometry is a technique that allows one to reconstruct the full wavefield originating from a virtual source inside a medium, assuming a receiver is present at the virtual source location. We discuss a method that creates a virtual source inside a medium from reflection data measured at the surface, without needing a receiver inside...
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
Searched for: author%3A%22Wapenaar%2C+C.P.A.%22
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