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Stabilized inverse Q filtering is a data processing technology for enhancing the resolution of reflection seismology images where the stability of the method used is considered. Q is the anelastic attenuation factor or the seismic quality factor, a measure of the energy loss as the seismic wave moves. To obtain a solution when we make computations with a seismic model we always have to consider the problem of instability and try to obtain a stabilized solution for seismic inverse Q filtering. ==Basics== When a wave propagates through subsurface materials both energy dissipation and velocity dispersion takes place. Inverse Q filtering is a method to restore the energy loss due to energy dissipation (amplitude compensation) and to correct the time-shift of the data due to velocity dispersion. Wang has written an excellent book on the subject of inverse Q filtering, (Seismic inverse Q filtering (2008) ), and discuss the subject of stabilizing the method. He writes: “The phase-only inverse Q filter mentioned above is unconditionally stable. However, if including the accompanying amplitude compensation in the inverse Q filter, stability is a major issue of concern in implementation.”〔Wang 2008 p.64〕 Hale (1981)〔Hale, D, 1981 Q-adaptive deconvolution: SEP report 30. p.140〕 found that the inverse Q filter overcompensated the amplitudes for the later events in a seismic trace. Therefore, in order to obtain reasonable amplitude, the amplitude spectrum of the computed filter has to be clipped at some maximum gain to prevent undue amplitude at later times. On basis of this concept Wang proposed a stabilized inverse Q filtering approach that was able to compensate simultaneously for both attenuation and dispersion.”〔Wang 2008 p.66〕 The unclipped version of Wang’s solution is presented in the wikipedia article seismic inverse Q filtering. The solution is based on the theory of wavefield downward continuation. In this outline here I will compute on a clipped version by introducing low-pass filtering. Both Hale and Wang introduced low-passfiltering as a method for stabilization. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Stabilized inverse Q filtering」の詳細全文を読む スポンサード リンク
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