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Preconditioned acoustic least-squares two-way wave-equation migration with exact adjoint operator
GEOPHYSICS, 2018We have investigated the problem of designing the forward operator and its exact adjoint for two-way wave-equation least-squares migration. We study the problem in the time domain and pay particular attention to the individual operators that are required by the algorithm.
Linan Xu, Mauricio D. Sacchi
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A new upward and downward wavefield continuation for two-way wave equation migration
International Meeting for Applied Geoscience & Energy, 2015Summary I describe a new two-way wave equation migration that combines the efficiency of one-way wave equation migration with the imaging capability of reverse time migration. This approach extrapolates the wavefield in the frequency-wavenumber domain along the depth axis.
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SEG Technical Program Expanded Abstracts 2004, 2004
Theory An iterative numerical method for solving the wave equation in an inhomogeneous medium with constant density is presented. The method is based on a Krylov iterative method and enhanced by a powerful preconditioner. For the preconditioner, a complex ShiftedLaplace operator is proposed, designed specifically for the wave equation.
Yogi A. Erlangga +4 more
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Theory An iterative numerical method for solving the wave equation in an inhomogeneous medium with constant density is presented. The method is based on a Krylov iterative method and enhanced by a powerful preconditioner. For the preconditioner, a complex ShiftedLaplace operator is proposed, designed specifically for the wave equation.
Yogi A. Erlangga +4 more
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Chinese Journal of Geophysics, 2005
By adding one complex frequency (the real part for frequency and the imaginary part for damping factor) into the frequency-domain wave equation, the energy or amplitude after first-arrival wave can be damped. Therefore, the calculation of first-arrival traveltime and amplitude can be transformed into the picking of the maximum energy and its phase in ...
Yi-Long QIN +6 more
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By adding one complex frequency (the real part for frequency and the imaginary part for damping factor) into the frequency-domain wave equation, the energy or amplitude after first-arrival wave can be damped. Therefore, the calculation of first-arrival traveltime and amplitude can be transformed into the picking of the maximum energy and its phase in ...
Yi-Long QIN +6 more
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International Conference on Automatic Control and Artificial Intelligence (ACAI 2012), 2012
In this paper, the wide-angle two-way parabolic Equation (PE) method is presented and applied for predicting both forward and backward electromagnetic waves propagation in urban environments. The buildings are assumed to be knife-edges or rectangular blocks with vertical sides and flat rooftops, and the terrain is assumed to be flat.
null Kun Wang +2 more
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In this paper, the wide-angle two-way parabolic Equation (PE) method is presented and applied for predicting both forward and backward electromagnetic waves propagation in urban environments. The buildings are assumed to be knife-edges or rectangular blocks with vertical sides and flat rooftops, and the terrain is assumed to be flat.
null Kun Wang +2 more
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AVA analysis and geological dip estimation via two-way wave-equation based extended images
SEG Technical Program Expanded Abstracts 2013, 2013In this paper, we present an efficient way to compute extended images for all subsurface offsets without explicitly calculating the source and receiver wavefields for all the sources. Because the extended images contain all possible subsurface offsets, we compute the angle-domain image gathers by selecting the subsurface offset that is aligned with the
Rajiv Kumar +2 more
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84th EAGE Annual Conference & Exhibition, 2023
J. Yang, J. Huang, H. Zhu, G. McMechan
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J. Yang, J. Huang, H. Zhu, G. McMechan
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Acoustic and elastic least-squares two-way wave equation migration with exact adjoint operator
2017A major problem in exploration seismology entails estimating subsurface structures and properties via linearized inversion. The problem is often called ''least-squares migration" where seismic imaging is posed as an iterative least-squares problem.
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Joint Migration Inversion Using Two-Way Wave Equation and Wavefield Separation
83rd EAGE Annual Conference & Exhibition, 2022Y. Sun, T. Fei
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Proceedings, 2014
In this paper, I solve the two-way wave equation for detecting primaries and internal multiple reflections scattered by every feature of the impedance and velocity model. My solution leads to a method for modelling and discriminating primary reflections and internal multiples.
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In this paper, I solve the two-way wave equation for detecting primaries and internal multiple reflections scattered by every feature of the impedance and velocity model. My solution leads to a method for modelling and discriminating primary reflections and internal multiples.
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