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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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Minato, S. (author), Ghose, R. (author)
Fluid flow through a fractured reservoir is often controlled by the large fractures. Seismically imaging these large fractures has the potential to illuminate their hydraulic properties.We derived a nonlinear imaging condition considering a medium containing nonwelded interfaces such as fractures for high-resolution fracture imaging. This was...
journal article 2015
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Ozmen, N. (author), Dapp, R. (author), Zapf, M. (author), Gemmeke, H. (author), Ruiter, N.V. (author), Van Dongen, K.W.A. (author)
Ultrasound is frequently used to evaluate suspicious masses in breasts. These evaluations could be improved by taking advantage of advanced imaging algorithms, which become feasible for low frequencies if accurate knowledge about the phase and amplitude of the wave field illuminating the volume of interest is available. In this study, we compare...
journal article 2015
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Soni, A.K. (author), Verschuur, D.J. (author)
For vertical-seismic-profiling (VSP) measurements, the use of blended acquisition, with time-overlapping shot records, can greatly reduce the downtime and, thereby, provide large cost savings. For directly imaging blended VSP measurements, we have used full-wavefield migration (FWM). FWM is an inversion-based imaging scheme that enables us to...
journal article 2015
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Kumar, A. (author), Blacquière, G. (author)
A subsurface image obtained from seismic data is influenced by the acquisition geometry, as it contains an acquisition foot-print which can obscure the true reflection response of the subsurface. Hence, the acquisition geometry should be designed in such a way that it allows high-quality images and fulfils the criteria for reservoir...
journal article 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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Dekker, C. (author), Tans, S.J. (author), Oberndorff, B. (author), Meyer, R. (author), Venema, L.C. (author)
journal article 1997
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Singh, S. (author), Snieder, R. (author), Behura, J. (author), van der Neut, J.R. (author), Wapenaar, C.P.A. (author), Slob, E.C. (author)
Recent work on retrieving the Green’s function with the Marchenko equation shows how these functions for a virtual source in the subsurface can be obtained from reflection data. The response to the virtual source is the Green’s function from the location of the virtual source to the surface. The Green’s function is retrieved using only the...
journal article 2015
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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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Bharadwaj, P. (author), Mulder, W.A. (author), Drijkoningen, G.G. (author)
Least-squares inversion of seismic reflection waveforms can reconstruct remarkably detailed models of the Earth’s subsurface. However, the cycle-skipping associated with the highfrequency waveforms are responsible for spurious local minima in its objective function. Therefore, it is often difficult for descent methods to converge to the true...
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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Bal, M.F. (author), Singh, M. (author), Braat, J.J.M. (author)
journal article 2004
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Tans, S.J. (author), Miedema, R. (author), Geerligs, L.J. (author), Dekker, C. (author), Wu, J. (author), Wegner, G. (author)
journal article 1997
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Kolkman, R.G.M. (author), Blomme, E. (author), Cool, T. (author), Bilcke, M. (author), Van Leeuwen, T.G. (author), Steenbergen, W. (author), Grimbergen, K.A. (author), Den Heeten, G.J. (author)
The feasibility of air-coupled ultrasound transducers to detect laser-induced ultrasound from artificial blood vessels embedded in an optically scattering phantom is demonstrated. These air-coupled transducers allow new applications in biomedical photoacoustic imaging where contact with tissue is not preferred. One promising application of such...
journal article 2010
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Moghaddam, P.P. (author), Keers, H. (author), Herrmann, F.J. (author), Mulder, W.A. (author)
Waveform inversion is the method of choice for determining a highly heterogeneous subsurface structure. However, conventional waveform inversion requires that the wavefield for each source is computed separately. This makes it very expensive for realistic 3D seismic surveys. Source-encoding waveform inversion, in which the sources are modeled...
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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Frank, J.G. (author), Ruigrok, E.N. (author), Wapenaar, C.P.A. (author)
Seismic interferometry allows for the creation of new seismic traces by cross correlating existing ones. With sufficient sampling of remote-source positions, it is possible to create a virtual source record by transforming a receiver location into a virtual source. The imaging technique developed here directly retrieves reflectivity information...
journal article 2014
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Ponziani, M. (author), Slob, E.C. (author), Luthi, S.M. (author), Bloemenkamp, R. (author), Le Nir, I. (author)
We studied the electric response of fractures with laboratory experiments and numerical simulations for a full-bore formation microimaging tool. The laboratory setup was designed and built to perform controlled experiments with accurate measurements of all principal properties involved for electric borehole imaging. These properties are...
journal article 2015
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Soni, A.K. (author), Verschuur, D.J. (author)
Blended source and/or simultaneous source acquisition for multi-offset and multi-azimuth VSP measurements can prove significantly beneficial in saving expensive borehole down-time. In the last few years, for the case of surface seismic data, it was proposed to redefine imaging and inversion of the blended data to handle the data directly without...
journal article 2013
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Venema, L.C. (author), Wildoer, J.W.G. (author), Tuinstra, H.L.J.T. (author), Dekker, C. (author), Rinzler, A.G. (author), Smalley, R.E. (author)
journal article 1997
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