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Shirmohammadi, F. (author), Weemstra, C. (author), Draganov, D.S. (author), Wapenaar, C.P.A. (author)
poster 2019
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Wapenaar, C.P.A. (author)
The matrix-vector wave equation is a compact first-order differential equation. It was originally used for the analysis of elastodynamic plane waves in laterally invariant media. It has been extended by various authors for laterally varying media. Other authors derived a similar formalism for other wave phenomena. This paper starts with a...
journal article 2019
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Wapenaar, C.P.A. (author), Reinicke Urruticoechea, C. (author)
Given the increasing interest for non-reciprocal materials, we propose a novel acoustic imaging method for layered non-reciprocal media. The method we propose is a modification of the Marchenko imaging method, which handles multiple scattering between the layer interfaces in a data-driven way. We start by reviewing the basic equations for wave...
journal article 2019
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Almagro Vidal, C. (author), van der Neut, J.R. (author), Wapenaar, C.P.A. (author)
Time-lapse changes in the subsurface can be analyzed by comparing seismic reflection data from two different states, one serving as the base survey and the second as the monitor survey. Conventionally, reflection data are acquired by placing active seismic sources at the acquisition surface. Alternatively, these data can be acquired from passive...
journal article 2019
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Wapenaar, C.P.A. (author), Brackenhoff, J.A. (author), Thorbecke, J.W. (author)
The earthquake seismology and seismic exploration communities have developed a variety of seismic imaging methods for passive- and active-source data. Despite the seemingly different approaches and underlying principles, many of those methods are based in some way or another on Green's theorem. The aim of this paper is to discuss a variety of...
journal article 2019
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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
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Meles, G.A. (author), van der Neut, J.R. (author), van Dongen, K.W.A. (author), Wapenaar, C.P.A. (author)
Wavefield focusing is often achieved by time-reversal mirrors, where wavefields emitted by a source located at the focal point are evaluated at a closed boundary and sent back, after time-reversal, into the medium from that boundary. Mathematically, time-reversal mirrors are derived from closed-boundary integral representations of reciprocity...
journal article 2019
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Brackenhoff, J.A. (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author)
We aim to monitor and characterize signals in the subsurface by combining these passive signals with recorded reflection data at the surface of the Earth. To achieve this, we propose a method to create virtual receivers from reflection data using the Marchenko method. By applying homogeneous Green's function retrieval, these virtual receivers...
journal article 2019
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Reinicke Urruticoechea, C. (author), Wapenaar, C.P.A. (author)
The homogeneous Green’s function is the difference between an impulse response and its time-reversal. According to existing representation theorems, the homogeneous Green’s function associated with source–receiver pairs inside a medium can be computed from measurements at a boundary enclosing the medium. However, in many applications such as...
journal article 2019
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Wapenaar, C.P.A. (author), Brackenhoff, J.A. (author), Thorbecke, J.W. (author), van der Neut, J.R. (author), Slob, E.C. (author), Verschuur, D.J. (author)
A virtual acoustic source inside a medium can be created by emitting a time-reversed point-source response from the enclosing boundary into the medium. However, in many practical situations the medium can be accessed from one side only. In those cases the time-reversal approach is not exact. Here, we demonstrate the experimental design and...
journal article 2018
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Meles, G.A. (author), Wapenaar, C.P.A. (author), Thorbecke, J.W. (author)
Marchenko redatuming is a novel scheme used to retrieve up- and downgoing Green's functions in an unknown medium.Marchenko equations are based on reciprocity theorems and are derived on the assumption of the existence of functions exhibiting space-time focusing properties once injected in the subsurface. In contrast to interferometry but...
journal article 2018
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Wapenaar, C.P.A. (author), Staring, M. (author)
In seismic monitoring, one is usually interested in the response of a changing target zone, embedded in a static inhomogeneous medium. We introduce an efficient method that predicts reflection responses at the Earth's surface for different target-zone scenarios, from a single reflection response at the surface and a model of the changing...
journal article 2018
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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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Zhang, L. (author), Slob, E.C. (author), van der Neut, J.R. (author), Wapenaar, C.P.A. (author)
We have derived an improved reverse time migration (RTM) scheme to image the medium without artifacts arising from internal multiple reflections. This is based on a revised implementation of Marchenko redatuming using a new time-truncation operator. Because of the new truncation operator, we can use the time-reversed version of the standard...
journal article 2018
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Staring, M. (author), Pereira, Roberto (author), Douma, Huub (author), van der Neut, J.R. (author), Wapenaar, C.P.A. (author)
We have developed an adaptive double-focusing method that is specifically designed for the field-data application of source-receiver Marchenko redatuming. Typically, the single-focusing Marchenko method is combined with a multidimensional deconvolution (MDD) to achieve redatuming. Our method replaces the MDD step by a second focusing step...
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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Cui, Tianci (author), Vasconcelos, Ivan (author), Manen, Dirk Jan Van (author), Wapenaar, C.P.A. (author)
Marchenko redatuming can retrieve the impulse response to a subsurface virtual source from the single-sided surface reflection data with limited knowledge of the medium. We illustrate the concepts and practical aspects of Marchenko redatuming on a simple 1D acoustic lossless medium in which the coupled Marchenko equations are exact. Defined...
journal article 2018
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Holicki, M.E. (author), Drijkoningen, G.G. (author), Wapenaar, C.P.A. (author)
Up–down wavefield decomposition is effectuated by a scaled addition or subtraction of the pressure and vertical particle velocity, generally on horizontal or vertical surfaces, and works well for data given on such surfaces. The method, however, is not applicable to decomposing a wavefield when it is given at one instance in time, i.e. on...
journal article 2018
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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
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