Searched for: subject%3A%22body%255C+waves%22
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Stumpf, M. (author), Gu, Junhong (author), Lager, I.E. (author)
A causality preserving interpretation of the electromagnetic (EM) leaky-wave (LW) propagation in space and time is proposed for the first time. The Cagniard-deHoop (CdH) joint transform technique is applied for elucidating the relation between time-domain (TD) head waves (HWs), body waves (BWs), Cherenkov wave effects, and LWs. It is...
journal article 2023
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Hartstra, I.E. (author), Wapenaar, C.P.A. (author)
Previous studies indicate that scattering may pose a trade-off for the performance of seismic interferometry (SI) applications for retrieving body-wave reflections of a target reflector. While it has been demonstrated that a higher scattering strength of the overburden improves the Green's function estimated by cross-correlation SI, other...
journal article 2023
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Chamarczuk, M. (author), Malinowski, M. (author), Draganov, D.S. (author), Grant, A. (author), Asgharzadeh, M. (author), Urosevic, M. (author)
Here we analyse ambient noise (AN) data generated during drilling of exploration boreholes and recorded using a dense array deployed over one of the numerous shallow iron-ore mineralization targets in the Pilbara region (Western Australia). Drilling and drilling-related operations were reoccurring in a sequence as described by the drillers’...
journal article 2021
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van IJsseldijk, J.E. (author), Ruigrok, Elmer (author), Verdel, Arie (author), Weemstra, C. (author)
Global phases, viz. seismic phases that travel through the Earth?s core, can be used to locally image the crust by means of seismic interferometry. This method is known as Global Phase Seismic Interferometry (GloPSI). Traditionally, GloPSI retrieves low-frequency information (up to 1 Hz). Recent studies, however, suggest that there is high...
journal article 2019
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Polychronopoulou, Katerina (author), Lois, Athanasios (author), Draganov, D.S. (author)
As the global need for mineral resources is constantly rising and the exploitable concentrations of these resources tend to become increasingly complex to explore and exploit, the mining industry is in a constant quest for innovative and cost‐effective exploration solutions. In this context, and in the framework of the Smart Exploration action,...
journal article 2019
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Harmankaya, U (author), Kaslilar, A. (author), Wapenaar, C.P.A. (author), Draganov, D.S. (author)
Unexpected geological structures can cause safety and economic risks during underground excavation. Therefore, predicting possible geological threats while drilling a tunnel is important for operational safety and for preventing expensive standstills. Subsurface information for tunneling is provided by exploratory wells and by surface...
journal article 2018
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Hartstra, I.E. (author), Almagro Vidal, C. (author), Wapenaar, C.P.A. (author)
Virtual Green's functions obtained by seismic interferometry (SI) can provide valuable reflectivity data that can complement tomographic inversion schemes. However, virtual reflections are affected by illumination irregularities that are typical of earthquake-induced wavefields recorded by the receiver array. As a consequence, irregular...
journal article 2018
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Almagro Vidal, C. (author), van der Neut, J.R. (author), Verdel, Arie (author), Hartstra, I.E. (author), Wapenaar, C.P.A. (author)
Passive seismic interferometry enables the estimation of the reflection response of the subsurface using passive receiver recordings at the surface from sources located deep in the Earth. Interferometric imaging makes use of this retrieved reflection response in order to study the subsurface. Successful interferometric imaging relies on the...
journal article 2018
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Spetzler, J. (author), Dost, Bernard (author)
Induced earthquakes due to gas production have taken place in the province of Groningen in the northeast of The Netherlands since 1986. In the first years of seismicity, a sparse seismological network with large station distances from the seismogenic area in Groningen was used. The location of induced earthquakes was limited by the few and...
journal article 2017
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Hartstra, I.E. (author), Almagro Vidal, C. (author), Wapenaar, C.P.A. (author)
Our objective is to complement lithospheric seismic tomography with an interferometric method to retrieve high-resolution reflectivity images from local earthquake recordings. The disadvantage of using local earthquakes for the retrieval of reflected body-waves is their usual sparse distribution. We propose an alternative formulation of passive...
journal article 2017
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Minato, S. (author), Ghose, R. (author)
Though well known for layer boundaries, the use of amplitude-versus-offset (AVO) variations for non-welded boundaries like fractures is not yet investigated. Depending on the seismic wavelength used, fractures can be regarded as thin, compliant zones in rocks, in different scales. We explore the potential of multiangle AVO inversion of P-P and P...
journal article 2016
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Nishitsuji, Y. (author), Mori, J. (author)
We estimated source parameters of 216 intermediate-depth (65–150 km) earthquakes (Mw 4.0–7.0) in the Pacific slab beneath Japan along using Hi-net data. We made determinations of static stress drop, radiated energy and radiation efficiency, along with estimates of the whole path attenuation, to study the source scaling as a function of...
journal article 2013
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Kudarova, A. (author), Van Dalen, K.N. (author), Drijkoningen, G.G. (author)
An effective poroelastic model is proposed that describes seismic attenuation and dispersion in periodically layeredmedia. In this model, the layers represent mesoscopic-scale heterogeneities (larger than the grain and pore sizes but smaller than the wavelength) that can occur both in fluid and solid properties. The proposed effectivemedium is...
journal article 2013
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Draganov, D.S. (author), Campman, X. (author), Thorbecke, J.W. (author), Verdel, A. (author), Wapenaar, C.P.A. (author)
The successful surface waves retrieval in solid?Earth seismology using long?time correlations and subsequent tomographic images of the crust have sparked interest in extraction of subsurface information from noise in the exploration seismology. Subsurface information in exploration seismology is usually derived from body?wave reflections >?1?Hz,...
journal article 2013
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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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Van Dalen, K.N. (author)
The characterization of porous materials (e.g., sandstone) is very important for geotechnical and reservoir engineers. For this purpose, often use is made of acoustic waves that are sent through the medium. The desired material parameters can then be estimated from the measured signals. However, often only the velocity or the attenuation of the...
doctoral thesis 2011
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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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Van Leeuwen, T. (author), Mulder, W.A. (author)
Wave-equation traveltime tomography tries to obtain a subsurface velocity model from seismic data, either passive or active, that explains their traveltimes. A key step is the extraction of traveltime differences, or relative phase shifts, between observed and modelled finite-frequency waveforms. A standard approach involves a correlation of the...
journal article 2010
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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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Groenenboom, J. (author), Duijndam, A.J.W. (author), Fokkema, J.T. (author)
conference paper 1995
Searched for: subject%3A%22body%255C+waves%22
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