Deconvolution偏移反褶积ppt课件.pptVIP

临床医学于波心房选择性钠通道阻滞剂在房颤中的应用颅内非肿瘤性病变的影像学表现基础医学慢性鼻窦炎鼻息肉围手术期综合治疗的临床指引泌尿生殖道感染衣原体检测和支原体培养及药敏结果分析 Migration Migration Intuitive Least Squares Green’s Theorem 2-way time (x-x ) + y 2 2 c/2 ? xx = ? xx + T o ZO Migration Smear Reflections along Fat Circles x x d(x , ) ? xx Thickness = c*T /2 o Where did reflections come from? 1-way time ZO Migration Smear Reflections along Fat Circles ? x Sum Hey, that’s our ZO migration formula d(x , ) ? xx 1-way time ZO Migration Smear Reflections along Circles ? x Sum In-Phase Out-of--Phase d(x , ) ? xx m(x)= Migration Migration Intuitive Least Squares Green’s Theorem Forward Problem: d=Lm m=L d T Born Forward Modeling d(x) = ? x’ ~ d = ? L m ij j j i g(x|x’) A(x,x’) ? xx’ ? i e m(x’) reflectivity Given: d = Lm Seismic Inverse Problem Find: m(x,y,z) Soln: min || Lm-d || 2 m = [L L] L d T T -1 ‘ L d T migration waveform inversion Forward Modeling (d = Lo) d(x) = ? x’ ~ g(x|x’) A(x,x’) ? xx’ ? i e o(x’) d(x) ~ m(x’) x d(x, ) ? xx’ Fourier Transform ? ? ? ? ZO Depth Migration (o L d) T M(x’) reflectivity ? x d(x, ) A(x,x’) ? xx’ = .. Review Inverse Acoustic Problem Find: m( r ) (c - c )/(c + c ) 1 1 2 2 r Given: d(r ) r m r ) ( Soln: L d T Soln: r o r d r r ) ( ) ( ò g r m r ) ( r dr * M(x’) reflectivity ? x d(x, ) A(x,x’) ? xx’ = Smear Sum Data ZO Data ZO Data Migration 0 km 7 km 0 km 3 km Least Squares Recall: Lm=d ? j ij Find: m that minimizes sum of squared residuals r = L m - d j i i (r ,r) = ([Lm-d],[Lm-d]) = m L Lm -2m Ld-d d L Lm = Ld Normal equations For all i (r ,r) d dm i = 2 m L Lm -2 m Ld d dm i d dm i = 0 Prestack Migration W(? ) ~ A(x,x’) ? xx’ ? i e ? x’ ? x’x’’ ? i e A(x’’,x’) m(x) = d(x’) d? ò d? ò ~ d(x’, ? + ? ) xx’ x’x’’ A(x,x’) ? x’ A(x’’,x’) = * - - Broadband case W(? )=1 ~ Narrow band case: direct wave correlated with data ..