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Polychronopoulou, Katerina (author), Malinowski, Michal (author), Cyz, Marta (author), Martakis, Nikos (author), Apostolopoulos, George (author), Draganov, D.S. (author)
As the global need for aluminum constantly rises, bauxite is considered to be a critical mineral, and the mining industry is in search of new and effective exploration solutions. In this context, we design and implement a purely earthquake-based passive seismic survey at the Gerolekas bauxite mining site in Greece. It is a very difficult...
journal article 2023
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Chamarczuk, Michał (author), Draganov, D.S. (author), Quiros, Diego (author), Malinowski, Michał (author)
Most of the ambient-noise studies are performed with sensor arrays located at the surface. Passive recordings containing seismic arrivals from subsurface sources could be seen as having a geometry resembling reverse vertical seismic profiling (RVSP). In such scenarios, the intersource seismic-interferometry technique can be used to redatum...
journal article 2022
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Liu, J. (author), Draganov, D.S. (author), Ghose, R. (author)
Seismic incoherent noise and waves scattered from objects in the crossline directions can cause 2D elastic full-waveform inversion (FWI) to produce artifacts in the resulting 2D models. We develop a complete workflow that can determine subsurface S-wave velocity (VS) models inverted from 2D near-surface seismic data more stably. We make use...
journal article 2022
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Liu, J. (author), Draganov, D.S. (author), Ghose, R. (author), Bourgeois, Q. (author)
Detecting small-size objects is a primary challenge at archaeological sites due to the high degree of heterogeneity present in the near surface. Although high-resolution reflection seismic imaging often delivers the target resolution of the subsurface in different near-surface settings, the standard processing for obtaining an image of the...
journal article 2021
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Chamarczuk, M. (author), Malinowski, M. (author), Nishitsuji, Y. (author), Thorbecke, J.W. (author), Koivisto, E. (author), Heinonen, S. (author), Juurela, S. (author), Mężyk, M. (author), Draganov, D.S. (author)
The main issues related to passive-source reflection imaging with seismic interferometry (SI) are inadequate acquisition parameters for sufficient spatial wavefield sampling and vulnerability of surface arrays to the dominant influence of the omnipresent surface-wave sources. Additionally, long recordings provide large data volumes that...
journal article 2019
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Bordoni, Federica (author), Lopez Dekker, F.J. (author), Krieger, Gerhard (author)
Future spaceborne synthetic aperture radar (SAR) systems are expected to deliver enormous quantity of data. Accordingly, the observation plan becomes crucial for a proper allocation of the mission resources. A central challenge is to reduce the number of acquisitions by making the same image available for more applications. Here, a relevant...
journal article 2018
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Agarwal, Girish (author), Allen, Roland E. (author), Bezděková, Iva (author), Boyd, Robert W. (author), Chen, Goong (author), Hanson, R. (author), Hawthorne, Dean L. (author), Hemmer, Philip (author), Kim, Moochan B. (author), Kocharovskaya, Olga (author), Lee, D. (author), Lidström, Sebastian K. (author), Lidström, Suzy (author), Losert, Harald (author), Maier, Helmut (author), Neuberger, John W. (author), Padgett, Miles J. (author), Raizen, Mark (author), Rajendran, Surjeet (author), Rasel, Ernst (author), Schleich, Wolfgang P. (author), Scully, Marlan O. (author), Shchedrin, Gavriil (author), Shvets, Gennady (author), Sokolov, Alexei (author), Svidzinsky, Anatoly (author), Walsworth, Ronald L. (author), Weiss, Rainer (author), Wilczek, Frank (author), Willner, Alan E. (author), Yablonovich, Eli (author), Zheludev, Nikolay (author)
The Winter Colloquium on the Physics of Quantum Electronics (PQE) has been a seminal force in quantum optics and related areas since 1971. It is rather mind-boggling to recognize how the concepts presented at these conferences have transformed scientific understanding and human society. In January 2017, the participants of PQE were asked to...
journal article 2018
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Nishitsuji, Y. (author), Minato, S. (author), Boullenger, B. (author), Gomez, M (author), Wapenaar, C.P.A. (author), Draganov, D.S. (author)
We have developed an application of passive seismic interferometry (SI) using P-wave coda of local earthquakes for the purpose of crustal-scale reflection imaging. We processed the reflection gathers retrieved from SI following a standard seismic processing in exploration seismology. We applied SI to the P-wave coda using crosscorrelation,...
journal article 2016
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Nishitsuji, Y. (author), Ruigrok, E (author), Gomez, M (author), Wapenaar, C.P.A. (author), Draganov, D.S. (author)
Obtaining detailed images of aseismic parts of subducting slabs remains a large challenge for understanding slab dynamics. Hypocenter mapping cannot be used for the purpose due to the absence of seismicity, whereas the use of receiver functions might be compromised by the presence of melt. Global tomography can be used to identify the presence...
journal article 2016
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Minato, S. (author), Ghose, R. (author)
The spatial heterogeneity along a fracture is a key determinant for fracture-associated mechanical and hydraulic properties of the subsurface. Laboratory experiments have been performed to test the applicability of the nonwelded interface representation to predict the frequency- and angle-dependent elastic response of a single fracture. The...
journal article 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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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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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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