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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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Draganov, D.S. (author), Campman, X. (author), Thorbecke, J.W. (author), Verdel, A. (author), Wapenaar, C.P.A. (author)
One application of seismic interferometry is to retrieve the impulse response (Green's function) from crosscorrelation of ambient seismic noise. Various researchers show results for retrieving the surface-wave part of the Green's function. However, reflection retrieval has proven more challenging. We crosscorrelate ambient seismic noise,...
journal article 2009
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Van der Burg, D. (author), Verdel, A. (author), Wapenaar, C.P.A. (author)
Trace inversion for reservoir parameters is affected by angle averaging of seismic data and wavelet distortion on the migration image. In an alternative approach to stochastic trace inversion, the data are inverted prestack before migration using 3D dynamic ray tracing. This choice makes it possible to interweave trace inversion with Kirchhoff...
journal article 2009
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Jardani, A. (author), Revil, A. (author), Slob, E.C. (author), Söllner, W. (author)
The interpretation of seismoelectrical signals is a difficult task because coseismic and seismoelectric converted signals are recorded simultaneously and the seismoelectric conversions are typically several orders of magnitude smaller than the coseismic electrical signals. The seismic and seismoelectric signals are modeled using a finite-element...
journal article 2009
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Wapenaar, C.P.A. (author), Van der Neut, J.R. (author), Ruigrok, E.N. (author)
We introduce seismic interferometry of passive data by multidimensional deconvolution (MDD) as an alternative to the crosscorrelation method. Interferometry by MDD has the potential to correct for the effects of source irregularity, assuming the first arrival can be separated from the full response. MDD applications can range from reservoir...
journal article 2008
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El Yadari, N. (author), Ernst, F. (author), Mulder, W. (author)
The effect of the near surface on seismic land data can be so severe that static corrections are insufficient. Full-waveform inversion followed by redatuming may be an alternative, but inversion will work only if the starting model is sufficiently close to the true model. As a first step toward determining a viscoelastic near-surface model, we...
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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Panea, I. (author), Drijkoningen, G.G. (author)
Coherent noise generated by surface waves or ground roll within a heterogeneous near surface is a major problem in land seismic data. Array forming based on single-sensor recordings might reduce such noise more robustly than conventional hardwired arrays. We use the minimum-variance distortionless-response (MVDR) beamformer to remove (aliased)...
journal article 2008
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Van Veldhuizen, E.J. (author), Blacquiere, G. (author), Berkhout, A.J. (author)
Increasingly, we must deal with complex subsurface structures in seismic exploration, often resulting in poor illumination and, therefore, poor image quality. Consequently, it is desirable to take into consideration the effects of wave propagation in the subsurface structure when designing an acquisition geometry. We developed a new, model-based...
journal article 2008
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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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Ruigrok, E.N. (author), Draganov, D.S. (author), Wapenaar, K. (author)
Progress in the imaging of the mantle and core is partially limited by the sparse distribution of natural sources; the earthquake hypocenters are mainly along the active lithospheric plate boundaries. This problem can be approached with seismic interferometry. In recent years, there has been considerable progress in the development of seismic...
journal article 2008
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Toxopeus, G. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author), Petersen, S. (author), Slob, E.C. (author), Fokkema, J.T. (author)
The simulation of migrated and inverted data is hampered by the high computational cost of generating 3D synthetic data, followed by processes of migration and inversion. For example, simulating the migrated seismic signature of subtle stratigraphic traps demands the expensive exercise of 3D forward modeling, followed by 3D migration of the...
journal article 2008
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Thorbecke, J.W. (author), Wapenaar, C.P.A. (author)
Seismic interferometry refers to the process of retrieving new seismic responses by crosscorrelating seismic observations at different receiver locations. Seismic migration is the process of forming an image of the subsurface by wavefield extrapolation. Comparing the expressions for backward propagation known from migration literature with the...
journal article 2007
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Spetzler, J. (author), Sijacic, D. (author), Wolf, K.H.A.A. (author)
Time-lapse seismic monitoring is the geophysical discipline whereby multiple data sets recorded at the same location but at different times are used to locate and quantify temporal changes in the elastic parameters of the subsurface. We validate a time-lapse monitoring method by crosswell tomography using two types of wavefield-modeling...
journal article 2007
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Turhan Taner, M. (author), Berkhout, A.J. (author), Treitel, S. (author), Kelamis, P.G. (author)
The statics problem, whether short wavelength, long wavelength, residual, or trim, has always been one of the more time-consuming and problematic steps in seismic data processing. We routinely struggle with issues such as poor signal-to-noise (S/N) ratio, cycle skipping, truncated refractors, wavelets with ambiguous first arrival times, etc....
journal article 2007
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Jocker, J. (author), Spetzler, J. (author), Smeulders, D.M.J. (author), Trampert, J. (author)
Ultrasonic measurements of acoustic wavefields scattered by single spheres placed in a homogenous background medium (water) are presented. The dimensions of the spheres are comparable to the wavelength and the wavelength and represent both positive (rubber) and negative (teflon) velocity anomalies with respect to the background medium. The...
journal article 2006
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Thorbecke, J. (author), Berkhout, A.J. (author)
The common-focus-point technology (CFP) describes prestack migration by focusing in two steps: emission and detection. The output of the first focusing step represents a CFP gather. This gather defines a shot record that represents the subsurface response resulting from a focused source wavefield. We propose applying the recursive shot-record,...
journal article 2006
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Zwartjes, P.M. (author), Gisolf, A. (author)
Many methods exist for interpolation of seismic data in one and two spatial dimensions, but few can interpolate properly in three or four spatial dimensions. Marine multi-streamer data typically are sampled relatively well in the midpoint and absolute offset coordinates but not in the azimuth because the crossline shot coordinate is...
journal article 2006
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Stoffa, P.L. (author), Sen, M.K. (author), Seifoullaev, R.K. (author), Pestana, R. (author), Fokkema, J.T. (author)
We present fast and efficient plane-wave migration methods for densely sampled seismic data in both the source and receiver domains. The methods are based on slant stacking over both shot and receiver positions (or offsets) for all the recorded data. If the data-acquisition geometry permits, both inline and crossline source and receiver...
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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