Abstract：As an improved ray migration method,Gaussian beam migration not only inherits the efficiency and flexibility of ray methods,but also has the imaging accuracy close to wave equation migration methods. Compared with traditional Gaussian beam migration in frequency domain,the method in time domain greatly improves computational efficiency by adjusting the imaging formula and converting frequency integral into the function of imaging time. As seismic azimuth becomes larger and recording spread becomes longer,the influence of anisotropy on seismic migration can't be ignored any longer. This paper introduces the anisotropic ray tracing algorithm based on phase velocity to time-domain Gaussian beam migration and optimizes the dynamic ray tracing correlation coefficient,and finally proposes a more efficient method for acoustic anisotropic media. Model tests have demonstrated that the method proposed has higher computational efficiency and better applicability while maintaining higher imaging accuracy than similar anisotropic algorithms,especially it can be used for imaging complex anisotropic structures.
Popov M M.A new method of computation of wave fields using Gaussian beams[J].Wave Motion,1982,4(1):85-97.
[2]
Červený V,Vaněk R J.Expansion of a plane wave into Gaussian beams[J].Studia Geophysica Et Geodaetica,1982,26(2):120-131.
[3]
Hill N R.Gaussian beam migration[J].Geophysics, 1990,55(11):1416-1428.
[4]
Hale D.Migration by the Kirchhoff,slant stack,and Gaussian beam methods[R].CWP Annual Project Review Meeting,Colorado School of Mines,1992,22-34.
[5]
Alkhalifah T.Gaussian beam depth migration for ani-sotropic media[J].Geophysics,1995,60(5):1474-1484.
[6]
Hill N R.Prestack Gaussian-beam depth migration[J].Geophysics,2001,66(4):1240-1250.
[7]
Nowack R L,Sen M K,Stoffa P L,et al.Gaussian beam migration for sparse common-shot and common-receiver data[C].SEG Technical Program Expanded Abstracts,2003,22:1114-1117.
[8]
Gray S H.Gaussian beam migration of common shot records[J].Geophysics,2005,70(4):S71-S77.
[9]
Zhu T.Kinematic and dynamic raytracing in aniso-tropic media-a phase-velocity formulation[C].SEG Technical Program Expanded Abstracts,2005,24:96-99.
[10]
Zhu T,Gray S H,Wang D.Prestack Gaussian-beam depth migration in anisotropic media[J].Geophysics,2007,72(3):S133-S138.
[11]
Gray S H,Bleistein N.True-amplitude Gaussian-beam migration[J].Geophysics,2009,74(2):S11-S23.
[12]
Bleistein N,Zhang Y,Xu S,et al.Migration/inver-sion:think image point coordinates,process in acquisition surface coordinates[J].Inverse Problems,2005,21(5):1715-1744.
岳玉波.复杂介质高斯束偏移成像方法研究[D].中国石油大学(华东),山东青岛,2011.YUE Yubo.Study on Gaussian Beam Migration Methods in Complex Medium[D].China University of Petroleum (East China),Qingdao,Shandong,2011.
[15]
段鹏飞,程玖兵,陈爱萍,等.TI介质局部角度域高斯束叠前深度偏移成像[J].地球物理学报,2013,56(12):4206-4214.DUAN Pengfei,CHENG Jiubing,CHEN Aiping,et al.Local angle-domain Gaussian beam prestack depth migration in a TI medium[J].Chinese Journal of Geophysics,2013,56(12):4206-4214.
[16]
高成,孙建国,齐鹏,等.2D共炮时间域高斯波束偏移[J].地球物理学报,2015,58(4):1333-1340.GAO Cheng,SUN Jianguo,QI Peng,et al.2-D Gau-ssian-beam migration of common-shot records in time domain[J].Chinese Journal of Geophysics,2015,58(4):1333-1340.
[17]
杨晶,黄建平.基于汉宁窗函数滤波时间域高斯束成像方法[J].地球物理学进展,2018,33(3):1161-1166.YANG Jing and HUANG Jianping.Time domain Gaussian beam migration method based Hanning window filtering[J].Progress in Geophysics,2018,33(3):1161-1166.
[18]
吴娟,白敏,张华.基于高斯束偏移的鬼波压制[J].石油地球物理勘探,2018,53(3):443-448.WU Juan,BAI Min and ZHANG Hua.Deghosting with Gaussian beam migration[J].Oil Geophysical Prospecting,2018,53(3):443-448.
[19]
石星辰,毛伟建,栗学磊.矢量黏弹性衰减补偿高斯束偏移[J].地球物理学报,2019,62(4):1480-1491.SHI Xingchen,MAO Weijian,LI Xuelei.Viscoelastic Q-compensated Gaussian beam migration based on vector-wave imaging[J].Chinese Journal of Geophy-sics,2019,62(4):1480-1491.
