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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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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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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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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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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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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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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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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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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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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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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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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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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 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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Abubakar, A. (author), Hu, W. (author), Habashy, T.M. (author), Van den Berg, P.M. (author)
We have applied the finite-difference contrast-source inversion (FDCSI) method to seismic full-waveform inversion problems. The FDCSI method is an iterative nonlinear inversion algorithm. However, unlike the nonlinear conjugate gradient method and the Gauss-Newton method, FDCSI does not solve any full forward problem explicitly in each iterative...
journal article 2009
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Wapenaar, C.P.A. (author), Slob, E.C. (author), Snieder, R. (author)
We have analyzed the far-field approximation of the Green's function representation for seismic interferometry. By writing each of the Green's functions involved in the correlation process as a superposition of a direct wave and a scattered wave, the Green's function representation is rewritten as a superposition of four terms. When the...
journal article 2010
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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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Wapenaar, C.P.A. (author), Draganov, D.S. (author), Snieder, R. (author), Campman, X. (author), Verdel, A. (author)
Seismic interferometry involves the crosscorrelation of responses at different receivers to obtain the Green's function between these receivers. For the simple situation of an impulsive plane wave propagating along the x-axis, the crosscorrelation of the responses at two receivers along the x-axis gives the Green's function of the direct wave...
journal article 2010
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Wapenaar, C.P.A. (author), Slob, E.C. (author), Snieder, R. (author), Curtis, A. (author)
In the 1990s, the method of time-reversed acoustics was developed. This method exploits the fact that the acoustic wave equation for a lossless medium is invariant for time reversal. When ultrasonic responses recorded by piezoelectric transducers are reversed in time and fed simultaneously as source signals to the transducers, they focus at the...
journal article 2010
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