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Wapenaar, C.P.A. (author), Van der Neut, J.R. (author), Draganov, D.S. (author)
Under conditional circumstances, the correlation of noise at two receivers is approximately proportional to the Green’s function between these receivers. Hence, the correlation process turns one of the receivers into a virtual source, of which the response is observed by the other receiver. This principle, also known as ambient-noise...
conference paper 2015
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Van der Neut, J.R. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author), Slob, E.C. (author)
Focusing functions are defined as wavefields that focus at a specified location in a heterogeneous subsurface. These functions can be directly related to Green's functions and hence they can be used for seismic imaging of complete wavefields, including not only primary reflections but all orders of internal multiples. Recently, it has been shown...
conference paper 2015
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Liu, Y. (author), Arntsen, B. (author), Wapenaar, C.P.A. (author), Van der Neut, J.R. (author)
The virtual source method has been applied successfully to retrieve the impulse response between pairs of receivers in the subsurface. This method is further improved by an updown separation prior to the crosscorrelation to suppress the reflections from the overburden and the free surface. In a reversed situation where the sources are in the...
conference paper 2014
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Van der Neut, J.R. (author), Wapenaar, C.P.A. (author), Thorbecke, J.W. (author), Vasconcelos, I. (author)
Recently, a novel iterative scheme was proposed to retrieve Green's functions in an unknown medium from its single-sided reflection response and an estimate of the propagation velocity. In Marchenko imaging, these Green's functions are used for seismic imaging with complete wavefields, including internal multiple reflections. In this way, common...
conference paper 2014
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Wapenaar, C.P.A. (author), Van der Neut, J.R. (author), Thorbecke, J.W. (author), Vasconcelos, I. (author), Van Manen, D.J. (author), Ravasi, M. (author)
Despite the close links between the fields of time-reversed acoustics, seismic interferometry and Marchenko imaging, a number of subtle differences exist. This paper reviews the various focusing conditions of these methods, the causality/acausality aspects of the corresponding focusing wavefields, and the requirements with respect to...
conference paper 2014
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Wapenaar, C.P.A. (author), Thorbecke, J.W. (author), Van der Neut, J.R. (author), Vasconcelos, I. (author), Slob, E.C. (author)
Marchenko imaging is a new way to deal with internal multiple scattering in migration. It has been designed for layered media with smooth interfaces. Here we analyze the performance of the Marchenko scheme for a medium with many point scatterers. Although the conditions for Marchenko imaging are violated, we observe from a numerical experiment...
conference paper 2014
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Van der Neut, J.R. (author), Vasconcelos, I. (author), Wapenaar, C.P.A. (author)
Recently, an iterative scheme was introduced to retrieve up- and downgoing Green’s functions at an arbitrary location F in the subsurface. The scheme uses the reflection data as acquired at the surface as input, together with an estimate of the direct arrival from the surface to location F, which is referred to as the initial focusing function....
conference paper 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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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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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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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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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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