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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 of wavefields observed at two receivers. Higher-mode surface waves cannot be properly retrieved when there is a lack of subsurface sources, which is often the case. In this paper, we present a multidimensional-deconvolution scheme that introduces an additional...
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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Wapenaar, C.P.A. (author), Thorbecke, J.W. (author)
The crosscorrelation of ambient acoustic noise observed at two receivers yields the impulse response between these receivers, assuming that the noise field is diffuse. In practical situations the noise field exhibits directionality, which imprints the angle-dependent correlation function. For the situation of a directional scatterer in a...
journal article 2013
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Ruigrok, E.N. (author), Almagro Vidal, C. (author), Wapenaar, C.P.A. (author)
With seismic interferometry reflections can be retrieved between station positions. In the classical form, the reflections are retrieved by an integration over sources. For a specific dataset, however, the actual source distribution might not be sufficient to approximate the source integral. Yet, there might be a dense distribution of receivers...
conference paper 2012
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Broggini, F. (author), Snieder, R. (author), Wapenaar, C.P.A. (author)
With seismic interferometry one can retrieve the response to a virtual source inside an unknown medium, if there is a receiver at the position of the virtual source. Using inverse scattering theory, we demonstrate that, for a 1D medium, the requirement of having an actual receiver inside the medium can be circumvented, going beyond seismic...
journal article 2012
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Ruigrok, E.N. (author), Wapenaar, C.P.A. (author)
A number of seismic methods exist to image the lithosphere below a collection of receivers, using distant earthquakes. In the current practice, especially mode-conversions in teleseismic phases are utilized. We present a new method that takes advantage of the availability of global phases. This method is called global-phase seismic...
journal article 2012
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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), Thorbecke, J.W. (author), Van der Neut, J.R. (author), Broggini, F. (author), Snieder, R. (author)
It has recently been shown that the response to a virtual source in the subsurface can be derived from reflection data at the surface and an estimate of the direct arrivals between the virtual source and the surface. Hence, unlike for seismic interferometry, no receivers are needed inside the medium. This new method recovers the complete...
conference paper 2012
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Harmankaya, U. (author), Kaslilar, A. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author), Draganov, D.S. (author)
In this study, non-physical (ghost) scattered surface waves are used to obtain the location of a near surface scatterer. The ghost is obtained from application of seismic interferometry to only one source at the surface. Different locations for virtual sources are chosen and ghost scattered surface waves for each of these virtual-source...
conference paper 2012
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Wapenaar, C.P.A. (author), Douma, H. (author)
The generalized optical theorem is an integral relation for the angle-dependent scattering amplitude of an inhomogeneous scattering object embedded in a homogeneous background. It has been derived separately for several scalar and vectorial wave phenomena. Here a unified optical theorem is derived that encompasses the separate versions for...
journal article 2012
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Wapenaar, C.P.A. (author), Van der Neut, J.R. (author), Thorbecke, J.W. (author)
Deblending of simultaneous-source data is usually considered to be an underdetermined inverse problem, which can be solved by an iterative procedure, assuming additional constraints like sparsity and coherency. By exploiting the fact that seismic data are spatially band-limited, deblending of densely sampled sources can be carried out as a...
journal article 2012
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Ruigrok, E.N. (author), Campman, X. (author), Wapenaar, K. (author)
The last few years there has been a growing number of body-wave observations in noise records. In 1973 Vinnik conjectured that P-waves would even be the dominant wavemode, at epicentral distances of about 40 degrees and onwards from an oceanic source. At arrays far from offshore storms, surface waves induced by nearby storms would not mask the...
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), 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 2011
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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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Wapenaar, C.P.A. (author), Ruigrok, E.N. (author), Van der Neut, J.R. (author), Draganov, D.S. (author)
The methodology of surface?wave retrieval from ambient seismic noise by crosscorrelation relies on the assumption that the noise field is equipartitioned. Deviations from equipartitioning degrade the accuracy of the retrieved surface?wave Green's function. A point?spread function, derived from the same ambient noise field, quantifies the...
journal article 2011
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Minato, S. (author), Matsuoka, T. (author), Tsuji, T. (author), Draganov, D.S. (author), Hunziker, J.W. (author), Wapenaar, C.P.A. (author)
Crosswell reflection method is a high-resolution seismic imaging method that uses recordings between boreholes. The need for downhole sources is a restrictive factor in its application, for example, to time-lapse surveys. An alternative is to use surface sources in combination with seismic interferometry. Seismic interferometry (SI) could...
journal article 2011
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Tetyukhina, D. (author), Van Vliet, L.J. (author), Luthi, S.M. (author), Wapenaar, C.P.A. (author)
Fluvio-deltaic sedimentary systems are of great interest for explorationists because they can form prolific hydrocarbon plays. However, they are also among the most complex and heterogeneous ones encountered in the subsurface, and potential reservoir units are often close to or below seismic resolution. For seismic inversion, it is therefore...
journal article 2010
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