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Verschuur, R. (author)
doctoral thesis 1927
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Verschuur, J.J. (author)
doctoral thesis 1946
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Verschuur, D.J. (author)
doctoral thesis 1991
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Berkhout, A.J. (author), Verschuur, D.J. (author)
Removal of surface and internal multiples can be formulated by removing the influence of downward-scattering boundaries and downward-scattering layers. The involved algorithms can be applied in a model-driven or a data-driven way. A unified description is proposed that relates both types of algorithms based on wave theory. The algorithm for the...
journal article 2005
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Van Dedem, E.J. (author), Verschuur, D.J. (author)
The theory of iterative surface-related multiple elimination holds for 2D as well as 3D wavefields. The 3D prediction of surface multiples, however, requires a dense and extended distribution of sources and receivers at the surface. Since current 3D marine acquisition geometries are very sparsely sampled in the crossline direction, the direct...
journal article 2005
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Verschuur, D.J. (author), Berkhout, A.J. (author)
In the past, the surface-multiple-removal method based on the feedback model has been successfully applied to many different field data sets. The extension of surface to internal multiples can be made by replacing shot records with common-focus-point (CFP) gathers, a CFP gather representing focused data with one source in the subsurface and all...
journal article 2005
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Berkhout, A.J. (author), Verschuur, D.J. (author)
Current multiple-removal algorithms in seismic processing use either differential moveout or predictability. If the differential moveout between primaries and multiples is small, prediction is the only option available. In the last decade, multidimensional prediction-error filtering by weighted convolution, such as surface-related multiple...
journal article 2006
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Berkhout, A.J. (author), Verschuur, D.J. (author)
Interpolation of data beyond aliasing limits and removal of noise that occurs within the seismic bandwidth are still important problems in seismic processing. The focal transform is introduced as a promising tool in data interpolation and noise removal, allowing the incorporation of macroinformation about the involved wavefields. From a physical...
journal article 2006
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Herrmann, F.J. (author), Wang, D. (author), Verschuur, D.J. (author)
In many exploration areas, successful separation of primaries and multiples greatly determines the quality of seismic imaging. Despite major advances made by surface-related multiple elimination (SRME), amplitude errors in the predicted multiples remain a problem. When these errors vary for each type of multiple in different ways (as a function...
journal article 2008
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Chitu, D.A. (author), Al-Ali, M.N. (author), Verschuur, D.J. (author)
In conventional migration velocity analysis methods, a velocity model is estimated that results in flattened events in common-image gathers. However, after this process, no information is available on the accuracy of this velocity model. A statistical analysis of velocity-model parameters is very difficult because of the integrated nature of the...
journal article 2008
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Van Groenestijn, G.J.A. (author), Verschuur, D.J. (author)
Accurate removal of surface-related multiples remains a challenge in many cases. To overcome typical inaccuracies in current multiple-removal techniques, we have developed a new primary-estimation method: estimation of primaries by sparse inversion (EPSI). EPSI is based on the same primary-multiple model as surface-related multiple elimination ...
journal article 2009
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Berkhout, A.J. (author), Blacquiere, G. (author), Verschuur, D.J. (author)
Seismic surveys are designed so that the time interval between shots is sufficiently large to avoid temporal overlap between records. To economize on survey time, the current compromise is to keep the number of shots to an acceptable minimum. The result is a poorly sampled source domain. We propose to abandon the condition of nonoverlapping shot...
journal article 2009
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Van Groenestijn, G.J.A. (author), Verschuur, D.J. (author)
ost wave-equation-based multiple removal algorithms are based on prediction and subtraction of multiples. Especially for shallow water, the prediction strongly relies on a correct interpolation of the missing near offsets. The subtraction of predicted multiples from the data can easily lead to the distortion of primaries if primaries and...
journal article 2009
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Van Groenestijn, G.J.A. (author), Verschuur, D.J. (author)
For passive seismic data, surface multiples are used to obtain an estimate of the subsurface responses, usually by a crosscorrelation process. This crosscorrelation process relies on the assumption that the surface has been uniformly illuminated by subsurface sources in terms of incident angles and strengths. If this is not the case, the...
journal article 2010
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Dragoset, B. (author), Verschuur, D.J. (author), Moore, I. (author), Bisley, R. (author)
Surface-related multiple elimination (SRME) is an algorithm that predicts all surface multiples by a convolutional process applied to seismic field data. Only minimal preprocessing is required. Once predicted, the multiples are removed from the data by adaptive subtraction. Unlike other methods of multiple attenuation, SRME does not rely on...
journal article 2010
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Verschuur, D.J. (author), Berkhout, A.J. (author)
This paper focuses on the concept of using blended data and multiple scattering directly in the migration process, meaning that the blended input data for the proposed migration algorithm includes blended surface-related multiples. It also means that both primary and multiple scattering contribute to the seismic image of the subsurface....
journal article 2011
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Lopez Angarita, G.A. (author), Verschuur, D.J. (author)
Recently, a new approach to multiple removal has been introduced: estimation of primaries by sparse inversion (EPSI). Although based on the same relationship between primaries and multiples as in surface-related multiple elimination (SRME), it involves quite a different process. Instead of the traditional prediction and subtraction of multiples,...
journal article 2012
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Berkhout, A.J. (author), Blacquiere, G. (author), Verschuur, D.J. (author)
In traditional seismic surveys, the firing time between shots is such that the shot records do not interfere in time. However, in the concept of blended acquisition, the records do overlap, allowing denser source sampling and wider azimuths in an economic way. A denser shot sampling and wider azimuths make that each subsurface gridpoint is...
journal article 2012
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Doulgeris, P. (author), Verschuur, D.J. (author), Blacquiere, G. (author)
Blended surveys have recently appeared in production environments. This underlines the need for processing tools that will either process the recorded data directly or perform the separation into single source data (deblending). An inversion technique for the separation of such data is described here. The problem parameterization utilises the...
conference paper 2012
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Berkhout, A.J. (author), Verschuur, D.J. (author)
The next generation migration technology considers multiple scattering as vital information, allowing the industry to generate significantly better images of the subsurface. The proposed full wavefield algorithm (FWM) makes use of two-way wave theory that is formulated in terms of one-way wavefields. We show that the current migration algorithms...
conference paper 2012
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