Abstract:Differential semblance optimization (DSO) is an approach to the inversion of the velocity which avoids the severe convergence associated with nonlinear least-squares inversion.DSO method-based wave-equation migration velocity analysis measures the focusing or flatness of image gathers and uses the deviation as the criterion to update the velocity.The DSO objective function has a decent global convexity property,therefore it can avoid the local minima problem,the gradient of objective function is smooth,it can inverse the background velocity accurately when there lacks low frequency data.Generally,ODCIGs is used to construct the objective function.In this paper,the authors use ADCIGs to construct the objective function,and the result of the test shows that DSO method with ADCIGs can estimate the correctness of velocity model directly and reflect the coupling relation between velocity and depth accurately.
[1] Sava P,Biondi B.Wave-equation migration velocity analysis . I. Theory [J].Geophysical Prospecting,2004,52(6):593-606. [2] Shen P,Symes W W.Automatic velocity analysis via shot profile migration [J].Geophysics,2008,73(5):VE49-VE59. [3] Albertin U,Etgen J,Maharramov M,et al.Adjoint wave-equation velocity analysis [C]//New Orleans:Expanded Abstracts of 76 th SEG Meeting,2006:3009-3013. [4] Toldi J L.Velocity analysis without picking [J].Geophysics,1989,54(2):191-199. [5] Chavent G,Jacewitz C A.Determination of background velocities by multiple migration fitting [J].Geophysics,1995,60(2):476-490. [6] Soubaras R,Gratacos B.Velocity model building by semblance maximization of modulated-shot gathers[J].Geophysics,2007,72(5):U67 U73. [7] Symes W W,Carazzone J J.Velocity inversion by differential semblance optimization [J].Geophysics,1991,56(5):654-663. [8] Symes W,Versteeg R.Velocity model determination using differential semblance optimization[C]//Washington:Expanded Abstracts of 63 rd SEG Meeting,1993:696-699. [9] Symes W W,Kern M.Inversion of reflection seismograms by differential semblance analysis:algorithm structure and synthetic examples1[J].Geophysical Prospecting,1994,42(6):565 614. [10] Mulder W A,Ten Kroode A P E.Automatic velocity analysis by differential semblance optimization [J].Geophysics,2002,67(4):1184-1191. [11] Symes W W.Migration velocity analysis and waveform inversion [J].Geophysical prospecting,2008,56(6):765-790. [12] Shen P,Symes W W,Stolk C C.Differential semblance velocity analysis by wave-equation migration[C]//Dallas:Expanded Abstracts of 73 rd SEG Meeting,2003:2132-2135. [13] Shen P,Symes W W,Morton S,et al.Differential semblance velocity analysis via shot profile migration [C]//SEG Technical Program Expanded Abstracts,SEG,2005:2249-2252. [14] Shen P.An RTM based automatic migration velocity analysis in image domain [C]//Las Vegas:Expanded Abstracts of 82 nd SEG Meeting,2012:1-5. [15] Fei W H,Williamson P.On the gradient artifacts in migration velocity analysis based on differential semblance optimization [C]//SEG Technical Program Expanded Abstracts,SEG,2010:4071-4076. [16] Yang T N,Sava P.Wave-equation migration velocity analysis using extended images [C]//Houston:SEG Technical Program Expanded Abstracts,SEG,2009:3715 3719. [17] Yang T N.Wavefield tomography using extended images[D].Colorado:Colorado School of Mines,2013. [18] Tang Y X,Biondi B.Target-oriented wavefield tomography using synthesized Born data [J].Geophysics,2011,76(5):WB191-WB207. [19] Shan G J,Wang Y.RTM based wave equation migration velocity analysis [C]//SEG Technical Program Expanded Abstracts,2013:4726-4731. [20] Shen P,Symes W W.Subsurface domain image warping by horizontal contraction and its application to wave-equation migration velocity analysis [C]//Houston:2013 SEG Annual Meeting,SEG,2013:4715-4719.