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Creating virtual vertical radar profiles from surface reflection ground penetrating radar data

Slob, E.C. (author), Hunziker, J.W. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author)

conference paper 2014

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Data-driven Green's function retrieval and application to imaging with multidimensional deconvolution

Broggini, F. (author), Wapenaar, C.P.A. (author), Van der Neut, J.R. (author), Snieder, R. (author)

An iterative method is presented that allows one to retrieve the Green's function originating from a virtual source located inside a medium using reflection data measured only at the acquisition surface. In addition to the reflection response, an estimate of the travel times corresponding to the direct arrivals is required. However, no detailed...

journal article 2014

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Surface wave retrieval in layered media using seismic interferometry by multidimensional deconvolution

Van Dalen, K.N. (author), Wapenaar, C.P.A. (author), Halliday, D.F. (author)

Virtual-source surface wave responses can be retrieved using the crosscorrelation (CC) of wavefields observed at two receivers. Higher mode surface waves cannot be properly retrieved when there is a lack of subsurface sources that excite these wavefields, as is often the case. In this paper, we present a multidimensional-deconvolution (MDD)...

journal article 2013

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Monitoring changes in velocity and Q using non-physical arrivals in seismic interferometry

Draganov, D.S. (author), Ghose, R. (author), Heller, K. (author), Ruigrok, E.N. (author)

Application of seismic interferometry to records from receivers at the Earth’s surface from sources in wells retrieves the reflection response measured at the receivers as if from virtual sources located also at the surface. When the wavefields experience intrinsic losses during propagation, non-physical arrivals (ghosts) would appear in the...

journal article 2012

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Interferometric redatuming by sparse inversion

Van der Neut, J. (author), Herrmann, F.J. (author)

Assuming that transmission responses are known between the surface and a particular depth level in the subsurface, seismic sources can be effectively mapped to this level by a process called interferometric redatuming. After redatuming, the obtained wavefields can be used for imaging below this particular depth level. Interferometric redatuming...

journal article 2012

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Marine Controlled-Source Electromagnetic Interferometry

Hunziker, J.W. (author)

In marine Controlled-Source Electromagnetics, a boat tows an electric source, whose signal is travelling on various paths to the receiver stations at the ocean bottom. Unfortunately, the signal does not only travel via the subsurface to the receivers, but also directly through the water and via the air-water interface. Signals travelling on the...

doctoral thesis 2012

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Extraction of P-wave reflections from microseisms

Ruigrok, E.N. (author), Campman, X. (author), Wapenaar, K. (author)

The last few years there has been a growing number of body-wave observations in noise records. In 1973 Vinnik conjectured that P-waves would even be the dominant wavemode, at epicentral distances of about 40 degrees and onwards from an oceanic source. At arrays far from offshore storms, surface waves induced by nearby storms would not mask the...

journal article 2011

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Seismic interferometry using multidimensional deconvolution and crosscorrelation for crosswell seismic reflection data without borehole sources

Minato, S. (author), Matsuoka, T. (author), Tsuji, T. (author), Draganov, D.S. (author), Hunziker, J.W. (author), Wapenaar, C.P.A. (author)

Crosswell reflection method is a high-resolution seismic imaging method that uses recordings between boreholes. The need for downhole sources is a restrictive factor in its application, for example, to time-lapse surveys. An alternative is to use surface sources in combination with seismic interferometry. Seismic interferometry (SI) could...

journal article 2011

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High-resolution lithospheric imaging with seismic interferometry

Ruigrok, E.N. (author), Campman, X. (author), Draganov, D.S. (author), Wapenaar, K. (author)

In recent years, there has been an increase in the deployment of relatively dense arrays of seismic stations. The availability of spatially densely sampled global and regional seismic data has stimulated the adoption of industry-style imaging algorithms applied to converted- and scattered-wave energy from distant earthquakes, leading to...

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

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Tutorial on seismic interferometry: Part 2 — Underlying theory and new advances

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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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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Retrieving electric resistivity data from self-potential measurements by cross-correlation

Slob, E.C. (author), Snieder, R. (author), Revil, A. (author)

We show that the two-point cross-correlation of self-potential field recordings is equal to the electric resistivity between the two points. This holds under the condition that spatially and temporally uncorrelated noise sources exist throughout the volume. These sources should have a known amplitude spectrum and their correlated strengths...

journal article 2010

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Interferometry by deconvolution of multicomponent multioffset GPR data

Slob, E.C. (author)

Interferometric techniques are now well known to retrieve data between two receivers by the cross correlation of the data recorded by these receivers. Cross-correlation methods for interferometry rely mostly on the assumption that the medium is loss free and that the sources are all around the receivers. A recently developed method introduced...

journal article 2009

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Seismic and electromagnetic interferometry: Retrieval of the earth's reflection response using crosscorrelation

Draganov, D. (author)

One of the goals of exploration geophysics is to obtain an image of the subsurface. In petroleum exploration and near-surface geophysics, this is best achieved using reflected waves. For this, a controlled seismic or electromagnetic source is placed at the surface, activated, and the wavefields that it creates are recorded at the surface after...

doctoral thesis 2007

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General representations for wavefield modeling and inversion in geophysics

Wapenaar, C.P.A. (author)

Acoustic, electromagnetic, elastodynamic, poroelastic, and electroseismic waves are all governed by a unified matrix-vector wave equation. The matrices in this equation obey the same symmetry properties for each of these wave phenomena. This implies that the wave vectors for each of these phenomena obey the same reciprocity theorems. By...

journal article 2007

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Retrieval of reflections from seismic background?noise measurements

Draganov, D.S. (author), Wapenaar, K. (author), Mulder, W. (author), Singer, J. (author), Verdel, A. (author)

The retrieval of the earth's reflection response from cross?correlations of seismic noise recordings can provide valuable information, which may otherwise not be available due to limited spatial distribution of seismic sources. We cross?correlated ten hours of seismic background?noise data acquired in a desert area. The cross?correlation results...

journal article 2007

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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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Seismic interferometry: Reconstructing the earth's reflection response

Draganov, D.S. (author), Wapenaar, C.P.A. (author), Thorbecke, J.W. (author)

In 1968, Jon Claerbout showed that the reflection response of a 1D acoustic medium can be reconstructed by autocorrelating the transmission response. Since then, several authors have derived relationships for reconstructing Green's functions at the surface, using crosscorrelations of (noise) recordings that were taken at the surface and that...

journal article 2006

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Green's function representations for seismic interferometry

Wapenaar, C.P.A. (author), Fokkema, J.T. (author)

The term seismic interferometry refers to the principle of generating new seismic responses by crosscorrelating seismic observations at different receiver locations. The first version of this principle was derived by Claerbout (1968), who showed that the reflection response of a horizontally layered medium can be synthesized from the...

journal article 2006