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Verdel, Arie (author), Wedemeijer, Harry (author), Paap, B (author), Vandeweijer, Vincent (author), Weemstra, C. (author), Jousset, Philippe (author), Franke, Steven (author), Blanck, Hanna (author), Águstsson, K. (author), Hersir, Gylfi Páll (author)
We present results from the application of ambient noise seismic interferometry (ANSI) to data that were recorded continuously in 2014 and 2015 at Iceland’s peninsula Reykjanes. The objective of this study is the retrieval of reflected body waves (P-waves) that provide high-resolution velocity-versus-depth as well as subsurface structural...
conference paper 2016
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Draganov, D.S. (author), Ghose, R. (author), Heller, H.K.J. (author)
Purpose: Time-lapse seismic monitoring constitutes the foundation for most monitoring programmes involving CO2 storage. When using time-lapse seismics, two major sources of uncertainty in the estimation of changes in the reservoir properties, like saturation and pressure, are the non-repeatability of the source positions and the difficulty to...
abstract 2016
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Rajan, R.T. (author), Boonstra, A.J. (author), Bentum, M. (author), Klein-Wolt, M. (author), Belien, F. (author), Arts, M. (author), Saks, N. (author), Van der Veen, A.J. (author)
The past decade has seen the advent of various radio astronomy arrays, particularly for low-frequency observations below 100 MHz. These developments have been primarily driven by interesting and fundamental scientific questions, such as studying the dark ages and epoch of re-ionization, by detecting the highly red-shifted 21 cm line emission....
journal article 2015
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Hartstra, I.E. (author), Wapenaar, C.P.A. (author)
We discuss a method to interferometrically retrieve the body wave reflection response from local high-frequency scattering coda wave fields with the purpose to obtain an input dataset suitable for the application of advanced exploration-type imaging methods
conference paper 2015
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Slob, E.C. (author), Hunziker, J.W. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author)
conference paper 2014
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Meskers, A.J.H. (author)
Lithographic exposure equipment for integrated circuit manufacturing requires ever more accurate position measurement systems, which is currently led by the advent of Extreme UltraViolet (EUV)-lithography machines. This PhD-research describes an interferometric displacement measurement system that possess the potential to foresee in the need for...
doctoral thesis 2014
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Meskers, A.J.H. (author), Spronck, J.W. (author), Munnig Schmidt, R.H. (author)
The use of optical fibers presents several advantages with respect to free-space optical transport regarding sourcefrequency delivery to individual heterodyne interferometers. Unfortunately, fiber delivery to individual coaxial heterodyne interferometers leads to an increase of (periodic) nonlinearity in the measurement, because transporting...
journal article 2014
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Wapenaar, C.P.A. (author), Slob, E.C. (author)
Recent work on the Marchenko equation has shown that the scalar 3-D Green’s function for a virtual source in the subsurface can be retrieved from the single-sided reflection response at the surface and an estimate of the direct arrival. Here, we discuss the first steps towards extending this result to multicomponent data. After introducing a...
journal article 2014
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Meskers, A.J.H. (author), Spronck, J.W. (author), Munnig Schmidt, R.H. (author)
Periodic nonlinearity (PNL) in displacement interferometers is a systematic error source that limits measurement accuracy. The PNL of coaxial heterodyne interferometers is highly influenced by the polarization state and orientation of the source frequencies. In this Letter, we investigate this error source and discuss two interferometer designs,...
journal article 2014
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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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Hermosa, N. (author), Rosales-Guzman, C. (author), Pereira, S.F. (author), Torres, J.P. (author)
We demonstrate an optical scheme for measuring the thickness of thin nanolayers with the use of light beam’s spatial modes. The novelty in our scheme is the projection of the beam reflected by the sample onto a properly tailored spatial mode. In the experiment described below, we are able to measure a step height smaller than 10 nm, i.e., one...
journal article 2014
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Martins, Joana E. (author), Hooper, Andy (author), Ruigrok, E.N. (author), Draganov, D.S. (author), Hanssen, R.F. (author), White, Robert (author), Soosalu, Heidi (author)
Torfajökull is the largest silicic volcanic centre in Iceland lying at the intersection of the rift zone (MidAtlantic Ridge) and the transform zone that connects to Reykjanes peninsula. It erupts infrequently,with only two eruptions in the last 1200 years, the latest of which was over 5 centuries ago. Yet, itsactive tectonic setting, persistent...
abstract 2014
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Pang, X. (author), Fischer, D.G. (author), Visser, T.D. (author)
We study the Gouy phase of a scalar wavefield that is focused by a lens suffering from primary spherical aberration. It is found that the Gouy phase has different behaviors at the two sides of the intensity maximum. This results in a systematic increase of the successive wavefront spacings around the diffraction focus. Since all lenses have some...
journal article 2013
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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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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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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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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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Zeitouny, M.G. (author)
In the recent years, precision measurement techniques in the field of optical science have improved with the advances in the phase stabilization of femtosecond lasers. Due to their unique properties, phase stabilized femtosecond lasers, also known as frequency comb lasers, are used as a versatile tools, not only for time and frequency metrology,...
doctoral thesis 2011
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Ellis, J.D. (author), Meskers, A.J.H. (author), Spronck, J.W. (author), Munnig Schmidt, R.H. (author)
Displacement interferometry is widely used for accurately characterizing nanometer and subnanometer displacements in many applications. In many modern systems, fiber delivery is desired to limit optical alignment and remove heat sources from the system, but fiber delivery can exacerbate common interferometric measurement problems, such as...
journal article 2011
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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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