Searched for: +
(1 - 19 of 19)
List view
Grid view
document
Scherders, Eva M.L. (author), Verschuur, D.J. (author), van Dongen, K.W.A. (author)
Imaging by inversion of acoustic or electromagnetic wave fields have applications in a wide variety of areas, such as non-destructive testing, biomedical applications, and geophysical exploration. Unfortunately, each modality suffers from its own application-specific limitations, typically being difficulties in distinguishing different...
conference paper 2022
document
van IJsseldijk, J.E. (author), Wapenaar, C.P.A. (author)
4D seismic studies aim to observe time-lapse changes in the subsurface between a baseline and a monitor study. These changes are generally small, and the seismic response from a deep reservoir can be concealed by reflections from shallow structures. Here, we introduce a novel way of isolating the reservoir response by means of the Marchenko...
book chapter 2021
document
Slob, E.C. (author), Wapenaar, C.P.A. (author), Treitel, Sven (author)
Acoustic inversion in one-dimension gives impedance as a function of travel time.<br/>Inverting the reflection response is a linear problem. Recursive methods, from top to bottom or vice versa, are known and use a fundamental wave field that is computed from the reflection response. An integral over the solution to the Marchenko equation, on the...
journal article 2020
document
Zhang, L. (author), Slob, E.C. (author)
Internal multiple reflections have been widely considered as coherent noise in measured seismic data, and many approaches have been developed for their attenuation. The Marchenko multiple elimination (MME) scheme eliminates internal multiple reflections without model information or adaptive subtraction. This scheme was originally derived from...
journal article 2020
document
Slob, E.C. (author), Zhang, L. (author)
Elimination of multiples from acoustic reflection data is important to reduce the effect of their presence in velocity model building and subsequent imaging. Many processing schemes assume only primary reflection events are present in the data. Free-surface multiple elimination is an established technology, but internal multiple elimination is...
conference paper 2019
document
Zhang, L. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author), Slob, E.C. (author)
We have developed a scheme that retrieves primary reflections in the two-way traveltime domain by filtering the data. The data have their own filter that removes internal multiple reflections, whereas the amplitudes of the retrieved primary reflections are compensated for two-way transmission losses. Application of the filter does not require...
journal article 2019
document
Zhang, L. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author), Slob, E.C. (author)
We have compared three data-driven internal multiple reflection elimination schemes derived from the Marchenko equations and inverse scattering series (ISS). The two schemes derived from Marchenko equations are similar but use different truncation operators. The first scheme creates a new data set without internal multiple reflections. The...
journal article 2019
document
Sripanich, Yanadet (author), Vasconcelos, Ivan (author), Wapenaar, C.P.A. (author)
The Marchenko method retrieves Green's functions between the acquisition surface and any arbitrary point in the medium. The process generally involves solving an inversion starting with an initial focusing function, e.g., a direct-wave Green's function from the desired subsurface position, typically obtained using an approximate velocity...
journal article 2019
document
Slob, E.C. (author), Wapenaar, C.P.A. (author), Treitel, Sven (author)
We derive a fast acoustic inversion method for a piecewise homogeneous horizontally layered medium. The method obtains medium parameters from the reflection response. The method can be implemented to obtain the parameters on either side of a reflector at an arbitrary depth. Three processing steps lead to the inversion result. First, we solve a...
conference paper 2018
document
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
document
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
document
Sherson, T.W. (author), Kleijn, W.B. (author), Heusdens, R. (author)
In this paper we propose a distributed reformulation of the linearly constrained minimum variance (LCMV) beamformer for use in acoustic wireless sensor networks. The proposed distributed minimum variance (DMV) algorithm, for which we demonstrate implementations for both cyclic and acyclic networks, allows the optimal beamformer output to be...
conference paper 2016
document
Knibbe, H.P. (author), Mulder, W.A. (author), Oosterlee, C.W. (author), Vuik, C. (author)
Three-dimensional reverse-time migration with the constant-density acoustic wave equation requires an efficient numerical scheme for the computation of wavefields. An explicit finite-difference scheme in the time domain is a common choice. However, it requires a significant amount of disk space for the imaging condition. The frequency-domain...
journal article 2014
document
Kutscha, H. (author)
Many seismic data processing and imaging processes require densely and regularly sampled data, whereas the actual measurements are mostly irregularly and sparsely sampled. Therefore, seismic data reconstruction methods are utilised as a pre-processing step. Within the class of transformation-based reconstruction techniques, observed seismic data...
doctoral thesis 2014
document
Bharadwaj, P. (author), Mulder, W.A. (author), Drijkoningen, G.G. (author)
Least-squares inversion of seismic reflection waveforms can reconstruct remarkably detailed models of the Earth’s subsurface. However, the cycle-skipping associated with the highfrequency waveforms are responsible for spurious local minima in its objective function. Therefore, it is often difficult for descent methods to converge to the true...
journal article 2013
document
Zhebel, E. (author), Minisini, S. (author), Kononov, A. (author), Mulder, W.A. (author)
With the rapid developments in parallel compute architectures, algorithms for seismic modeling and imaging need to be reconsidered in terms of parallelization. The aim of this paper is to compare scalability of seismic modeling algorithms: finite differences, continuous mass-lumped finite elements and discontinuous Galerkin finite elements. The...
journal article 2013
document
Broggini, F. (author), Snieder, R. (author), Wapenaar, C.P.A. (author)
Standard imaging techniques rely on the single scattering assumption. This requires that the recorded data do not include internal multiples, i.e. waves bouncing multiple times between layers before reaching the receivers at the acquisition surface. When multiple reflections are present in the data, standard imaging algorithms incorrectly image...
journal article 2013
document
Minisini, S. (author), Zhebel, E. (author), Kononov, A. (author), Mulder, W.A. (author)
Modeling and imaging techniques for geophysics are extremely demanding in terms of computational resources. Seismic data attempt to resolve smaller scales and deeper targets in increasingly more complex geologic settings. Finite elements enable accurate simulation of time-dependent wave propagation in heterogeneous media. They are more costly...
journal article 2013
document
Van Borselen, R.G. (author), Fokkema, J.T. (author), Van den Berg, P.M. (author)
In marine seismic acquisition, the free surface generates seismic events in our recorded data that are often categorized as noise because these events do not contain independent information about the subsurface geology. Ghost events are considered as such noise because these events are generated when the energy generated by the seismic source,...
journal article 2013
Searched for: +
(1 - 19 of 19)
List view
Grid view