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SEG Technical Program Expanded Abstracts 2015, 2015
We propose a new direct waveform inversion (DWI) idea to directly invert the waveform data without a global initial model and no iteration is needed for model updating. This approach offers the possibility to overcome the challenges in many full-waveform inversion (FWI) methods that are based on model perturbation approaches whose effectiveness ...
Zhonghan Liu, Yingcai Zheng*
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We propose a new direct waveform inversion (DWI) idea to directly invert the waveform data without a global initial model and no iteration is needed for model updating. This approach offers the possibility to overcome the challenges in many full-waveform inversion (FWI) methods that are based on model perturbation approaches whose effectiveness ...
Zhonghan Liu, Yingcai Zheng*
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Multiplier waveform inversion: A reduced-space full-waveform inversion by the method of multipliers
Geophysics, 2023ABSTRACT Full-waveform inversion (FWI) is a nonlinear optimization problem that addresses the estimation of subsurface model parameters by matching the predicted to the observed seismograms. We formulate FWI as a constrained optimization problem in which the regularization term is minimized subject to the nonlinear data matching ...
Gholami, Ali +2 more
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Applications of Waveform Inversion
70th EAGE Conference and Exhibition - Workshops and Fieldtrips, 2008Waveform inversion techniques aim to fit the entire seismic wavefield including those phases that conventional processing and migration seek to remove. Such methods have the potential to image the subsurface with significantly improved spatial resolution.
Z. Song, P. Childs
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1981
Abstract : A relative waveform inversion method has been developed which determines models that correctly predict waveform changes in a set of observed seismograms. By modeling changes in waveforms rather than absolute waveforms, a number of relatively poorly determined quantities, such as receiver function and Q, may be eliminated from the problem and
S. K. Kaufman, G. R. Mellman
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Abstract : A relative waveform inversion method has been developed which determines models that correctly predict waveform changes in a set of observed seismograms. By modeling changes in waveforms rather than absolute waveforms, a number of relatively poorly determined quantities, such as receiver function and Q, may be eliminated from the problem and
S. K. Kaufman, G. R. Mellman
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SeisFlows—Flexible waveform inversion software
Computers & Geosciences, 2018Abstract SeisFlows is an open source Python package that provides a customizable waveform inversion workflow and framework for research in oil and gas exploration, earthquake tomography, medical imaging, and other areas. New methods can be rapidly prototyped in SeisFlows by inheriting from default inversion or migration classes, and code can be ...
Ryan T. Modrak +3 more
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Waveform inversion of real CMP gathers
SEG Technical Program Expanded Abstracts 1999, 1999Automated waveform inversion suffers from a major flaw: the extremely poor behavior of the least-squares data misfit with respect to the low spatial frequency components of the slowness model. This prevents local optimization algorithms to meet the global minimum. An alternative to expensive global optimization methods is either to change the criterion
F. Clement, G. Chavent
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Full Waveform Inversion in Viscoelastic Media
2021Accumulations of gas hydrates in the bottom layers pose not only a potential threat to offshore engineering structures and shipping. They can also cause the release of significant volumes of methane into the atmosphere. The most natural way to detect gas hydrates is to use seismic methods.
Vladimir A. Cheverda +2 more
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Combining Full Waveform Inversion and Tomography: Full Waveform Inversion-guided Tomography
Proceedings, 2015With the new broadband acquisitions, allowing to record frequencies down to 2.5 Hz, and the new tomographic tools, allowing to resolve for vertical velocity components up to 6 Hz, we have moved velocity model building from the situation of a “mid-frequency gap” to the situation of an overlapping area in terms of the resolution we can expect from ...
T. Allemand, G. Lambaré
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Source-domain full-waveform inversions
Geophysics, 2019ABSTRACT Conventional full-waveform inversion (FWI) updates a velocity model by minimizing the data residuals between the predicted and observed data at the receiver positions. We have developed a new FWI to update the velocity model by minimizing virtual source artifacts at the receiver positions in the source-domain FWI (SFWI ...
Yulang Wu, George A. McMechan
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Resolution Analysis in Full Waveform Inversion
Geophysical Journal International, 2011We propose a new method for the quantitative resolution analysis in full seismic waveform inversion that overcomes the limitations of classical synthetic inversions while being computationally more efficient and applicable to any misfit measure. The method rests on (1) the local quadratic approximation of the misfit functional in the vicinity of an ...
Fichtner, A., Trampert, J.
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