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Seismic processing in the inverse data space

Berkhout, A.J. (author)

Until now, seismic processing has been carried out by applying inverse filters in the forward data space. Because the acquired data of a seismic survey is always discrete, seismic measurements in the forward data space can be arranged conveniently in a data matrix (P). Each column in the data matrix represents one shot record. If we represent...

journal article 2006

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A new iterative solver for the time-harmonic wave equation

Riyanti, C.D. (author), Erlangga, Y.A. (author), Plessix, R.E. (author), Mulder, W.A. (author), Vuik, C. (author), Oosterlee, C. (author)

The time-harmonic wave equation, also known as the Helmholtz equation, is obtained if the constant-density acoustic wave equation is transformed from the time domain to the frequency domain. Its discretization results in a large, sparse, linear system of equations. In two dimensions, this system can be solved efficiently by a direct method. In...

journal article 2006

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Seismic interferometry-turning noise into signal

Curtis, A. (author), Gerstoft, P. (author), Sato, H. (author), Snieder, R. (author), Wapenaar, C.P.A. (author)

Turning noise into useful data—every geophysicist's dream? And now it seems possible. The field of seismic interferometry has at its foundation a shift in the way we think about the parts of the signal that are currently filtered out of most analyses—complicated seismic codas (the multiply scattered parts of seismic waveforms) and background...

journal article 2006

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Simultaneous measurement of hysteresis in capillary pressure and electric permittivity for multiphase flow through porous media

Plug, W.J. (author), Slob, E.C. (author), Bruining, J. (author), Moreno Tirado, L.M. (author)

We present a tool that simultaneously measures the complex permittivity and the capillary pressure characteristics for multiphase flow. The sample holder is a parallel plate capacitor. A precision component analyzer is used to measure the impedance amplitude and phase angle as a function of frequency (1 kHz to 3 MHz). The complex impedance of...

journal article 2007

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The dynamics of statics

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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Application of a linear finite-frequency theory to time-lapse crosswell tomography in ultrasonic and numerical experiments

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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On the relation between seismic interferometry and the migration resolution function

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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Adaptive curvelet-domain primary-multiple separation

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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Assessing estimated velocity-depth models: Finding error bars in tomographic inversion

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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Passive seismic interferometry by multidimensional deconvolution

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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Estimating and correcting the amplitude radiation pattern of a virtual source

Van der Neut, J. (author), Bakulin, A. (author)

In the virtual source (VS) method we crosscorrelate seismic recordings at two receivers to create a new data set as if one of these receivers were a virtual source and the other a receiver. We focus on the amplitudes and kinematics of VS data, generated by an array of active sources at the surface and recorded by an array of receivers in a...

journal article 2009

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Estimating primaries by sparse inversion and application to near-offset data reconstruction

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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The concept of double blending: Combining incoherent shooting with incoherent sensing

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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Ray-based stochastic inversion of prestack seismic data for improved reservoir characterization

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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Estimation of primaries and near-offset reconstruction by sparse inversion: Marine data applications

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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Application of the finite-difference contrast-source inversion algorithm to seismic full-waveform data

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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On seismic interferometry, the generalized optical theorem, and the scattering matrix of a point scatterer

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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Exact expression for the effective acoustics of patchy-saturated rocks

Vogelaar, B. (author), Smeulders, D.M.J. (author), Harris, J. (author)

Seismic effects of a partially gas-saturated subsurface have been known for many years. For example, patches of nonuniform saturation occur at the gas-oil and gas-water contacts in hydrocarbon reservoirs. Open-pore boundary conditions are applied to the quasi-static Biot equations of poroelasticity to derive an exact analytic expression of the...

journal article 2010

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Estimation of primaries by sparse inversion from passive seismic data

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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Tutorial on seismic interferometry: Part 1 — Basic principles and applications

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