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Mulder, W.A. (author)
To estimate the depth errors in a subsurface model obtained from the inversion of seismic data, the stationary-phase approximation in a two-dimensional constant-velocity model with a dipped reflector is applied to migration with a time-shift extension. This produces two asymptotic solutions: one is a straight line, and the other is a curve....
journal article 2024
document
Mulder, W.A. (author)
Finite elements with mass lumping allow for explicit time stepping when modelling wave propagation and can be more efficient than finite differences in complex geological settings. In two dimensions on quadrilaterals, spectral elements are the obvious choice. Triangles offer more flexibility for meshing, but the construction of polynomial...
journal article 2023
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Mulder, W.A. (author)
Temporal dispersion correction of second-order finite-difference time stepping for numerical wave propagation modelling exploits the fact that the discrete operator is exact but for the wrong frequencies. Mapping recorded traces to the correct frequencies removes the numerical error. Most of the implementations employ forward and inverse...
journal article 2023
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van IJsseldijk, J.E. (author), Brackenhoff, Joeri (author), Thorbecke, J.W. (author), Wapenaar, C.P.A. (author)
The data-driven Marchenko method is able to redatum wavefields to arbitrary locations in the subsurface, and can, therefore, be used to isolate zones of specific interest. This creates a new reflection response of the target zone without interference from over- or underburden reflectors. Consequently, the method is well suited to obtain a...
journal article 2023
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Qu, S. (author), Verschuur, D.J. (author)
Traditional full-waveform inversion is a non-linear and ill-posed inversion problem. To reduce the non-linearity of it, joint migration inversion (joint migration inversion) was proposed as an alternative. Joint migration inversion tries to minimize the mismatch between measured and modelled reflection data. One key feature of joint migration...
journal article 2022
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Shirmohammadi, F. (author), Draganov, D.S. (author), Wapenaar, C.P.A. (author)
Seismic interferometry (SI) is a principle for retrieving responses between two receivers using cross-correlation. After the retrieval, one of the receivers acts as a virtual seismic source whose response is retrieved at the second receiver. Correct response retrieval relies on assumptions, among other, of a lossless medium being illuminated...
poster 2020
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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
document
Cox, B.E. (author)
Seismic images of the structure of the earth are a prerequisite for finding new hydrocarbon reservoirs. The quality of a seismic images is highly dependent on the accuracy of the velocity model of the subsurface. Conventional imaging consists of an iterative process between obtaining the image using a velocity model, and updating this model by...
doctoral thesis 2004
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