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A Model-Based Two-Way Wave-Equation Approach for Multiple Prediction
69th EAGE Conference and Exhibition incorporating SPE EUROPEC 2007, 2007B034 A Model-Based Two-Way Wave-Equation Approach for Multiple Prediction Z. Jiang* (BP) & B. Hornby (BP) SUMMARY Multiples from the sea bed or salt boundary are usually strong and will interfere and generate artifacts on migration images. In order to attenuate these multiples one approach is to first predict and then subtract them.
Z. Jiang, B. Hornby
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Principle of prestack migration based on the full elastic two-way wave equation
Geophysics, 1987Abstract The acoustic approximation in seismic migration is not allowed when the effects of wave conversion cannot be neglected, as is often the case in data with large offsets. Hence, seismic migration should ideally be founded on the full elastic wave equation, which describes compressional as well as shear waves in solid media ...
C. P. A. Wapenaar +2 more
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The Journal of the Acoustical Society of America, 1990
A method is introduced to calculate the influence of wind and temperature gradients in stratified media on sound propagating above an absorbing ground surface. It is based on the ‘‘two-way wave equation’’ for the Fourier transforms of the sound pressure P and its derivative V. The vector containing P and V is stepwise extrapolated through the medium in
L. Nijs, C. P. A. Wapenaar
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A method is introduced to calculate the influence of wind and temperature gradients in stratified media on sound propagating above an absorbing ground surface. It is based on the ‘‘two-way wave equation’’ for the Fourier transforms of the sound pressure P and its derivative V. The vector containing P and V is stepwise extrapolated through the medium in
L. Nijs, C. P. A. Wapenaar
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Angle-Domain Gathers Computation Using Poynting Vector of Two-Way Acoustic Wave Equation
Advanced Materials Research, 2014Based on two-way acoustic wave equation, we present a method for computing angle-domain common-image gathers for reverse time migration. The method calculates the propagation direction of source wave-fields and receiver wave-fields according to expression of energy flow density vectors (Poynting vectors) of acoustic wave equation in space-time domain ...
Jia Jia Yang, Bing Shou He, Ting Chen
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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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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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A new upward and downward wavefield continuation for two-way wave equation migration
SEG Technical Program Expanded Abstracts 2015, 2015Summary I describe a new two-way wave-equation migration that combines the efficiency of the one-way waveequation migration with the imaging capabilities of reverse time migration. The method extrapolates the wavefield in the frequency-wavenumber domain depth slice by depth slice. The key to this method is to perform upward continuation from the bottom
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Higher-order Boussinesq equations for two-way propagation of shallow water waves
European Journal of Mechanics - B/Fluids, 2006zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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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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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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