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Volume 61 Number 1
  • E-ISSN: 1365-2478

Abstract

ABSTRACT

Extended common‐image‐point gathers (CIP) constructed by wide‐azimuth TI wave‐equation migration contain all the necessary information for angle decomposition as a function of the reflection and azimuth angles at selected locations in the subsurface. The aperture and azimuth angles are derived from the extended images using analytic relations between the space‐ and time‐lag extensions using information which is already available at the time of migration, i.e. the anisotropic model parameters. CIPs are cheap to compute because they can be distributed in the image at the most relevant positions, as indicated by the geologic structure. If the reflector dip is known at the CIP locations, then the computational cost can be reduced by evaluating only two components of the space‐lag vector. The transformation from extended images to angle gathers is a planar Radon transform which depends on the local medium parameters. This transformation allows us to separate all illumination directions for a given experiment, or between different experiments. We do not need to decompose the reconstructed wavefields or to choose the most energetic directions for decomposition. Applications of the method include illumination studies in complex areas where ray‐based methods fail, and assuming that the subsurface illumination is sufficiently dense, the study of amplitude variation with aperture and azimuth angles.

© 2012 European Association of Geoscientists & Engineers
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2012-10-15
2024-04-19

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References

  1. AlkhalifahT.2000. An acoustic wave equation for anisotropic media. Geophysics 65, 1239–1250.
    [Google Scholar]
  2. AlkhalifahT. and FomelS.2010. Angle gathers in wave‐equation imaging for transversely isotropic media. Geophysical Prospecting , published online.
    [Google Scholar]
  3. AlkhalifahT. and SavaP.2010. A transversely isotropic medium with a tilted symmetry axis normal to the reflector. Geophysics (Letters) 75, A19–A24.
    [Google Scholar]
  4. BaysalE., KosloffD.D. and SherwoodJ.W.C.1983. Reverse time migration. Geophysics 48, 1514–1524.
    [Google Scholar]
  5. BerkhoutA.J.1982. Imaging of acoustic energy by wave field extrapolation . Elsevier.
    [Google Scholar]
  6. BiondiB. and SymesW.2004. Angle‐domain common‐image gathers for migration velocity analysis by wavefield‐continuation imaging. Geophysics 69, 1283–1298.
    [Google Scholar]
  7. BiondiB. and TisserantT.2004. 3D angle‐domain common‐image gathers for migration velocity analysis. Geophys. Prosp. 52, 575–591.
    [Google Scholar]
  8. Brandsberg‐DahlS., de HoopM.V. and UrsinB.2003. Focusing in dip and AvA compensation on scattering‐angle/azimuth common image gathers. Geophysics 68, 232–254.
    [Google Scholar]
  9. ClærboutJ.F.1985. Imaging the Earth’s interior . Blackwell Scientific Publications.
    [Google Scholar]
  10. ClarkeR., XiaG., KabirN., SirgueL. and MichellS.2006. Case study: A large 3D wide azimuth ocean bottom node survey in deepwater gom. SEG Technical Program Expanded Abstracts 25, 1128–1132.
    [Google Scholar]
  11. CullisonT. and SavaP.2011. An image‐guided method for automatically picking common‐image‐point gathers. Presented at the 81st Annual International Meeting, SEG, Expanded abstracts.
  12. de BruinC.G.M., WapenaarC.P.A. and BerkhoutA.J.1990. Angle‐dependent reflectivity by means of prestack migration. Geophysics 55, 1223–1234.
    [Google Scholar]
  13. DuveneckE. and BakkerP.M.2011. Stable p‐wave modeling for reverse‐time migration in tilted ti media. Geophysics 76, S65–S75.
    [Google Scholar]
  14. FletcherR.P., DuX. and FowlerP.J.2009. Reverse time migration in tilted transversely isotropic (TTI) media. Geophysics 74, WCA179–WCA187.
    [Google Scholar]
  15. FowlerP.J., DuX. and FletcherR.P.2010. Coupled equations for reverse time migration in transversely isotropic media. Geophysics 75, S11–S22.
    [Google Scholar]
  16. GrayS.H., EtgenJ., DellingerJ. and WhitmoreD.2001. Seismic migration problems and solutions. Geophysics 66, 1622–1640.
    [Google Scholar]
  17. KorenZ., RavveI., RagozaE., BartanaA., GeophysicalP. and KosloffD.2008. Full‐azimuth angle domain imaging. SEG Technical Program Expanded Abstracts 27, 2221–2225.
    [Google Scholar]
  18. McMechanG.A.1983. Migration by extrapolation of time‐dependent boundary values. Geophys. Prosp. 31, 413–420.
    [Google Scholar]
  19. MichellS., ShoshitaishviliE., ChergotisD., SharpJ. and EtgenJ.2006. Wide azimuth streamer imaging of mad dog; have we solved the subsalt imaging problem? SEG Technical Program Expanded Abstracts 25, 2905–2909.
    [Google Scholar]
  20. RegoneC.2006. Using 3D finite‐difference modeling to design wide azimuth surveys for improved subsalt imaging. SEG Technical Program Expanded Abstracts 25, 2896–2900.
    [Google Scholar]
  21. RickettJ. and SavaP.2002. Offset and angle‐domain common image‐point gathers for shot‐profile migration. Geophysics 67, 883–889.
    [Google Scholar]
  22. SavaP. and FomelS.2003. Angle‐domain common image gathers by wavefield continuation methods. Geophysics 68, 1065–1074.
    [Google Scholar]
  23. SavaP. and FomelS.2005. Coordinate‐independent angle‐gathers for wave equation migration. 75th Annual International Meeting, SEG, Expanded Abstracts, 2052–2055.
  24. SavaP. and FomelS.2006. Time‐shift imaging condition in seismic migration. Geophysics 71, S209–S217.
    [Google Scholar]
  25. SavaP. and VasconcelosI.2011. Extended imaging condition for wave‐equation migration. Geophysical Prospecting 59, 35–55.
    [Google Scholar]
  26. SavaP. and VladI.2011. Wide azimuth angle gathers for wave‐equation migration. Geophysics 76, S131–S141.
    [Google Scholar]
  27. ThomsenL.2001. Seismic anisotropy. Geophysics 66, 40–41.
    [Google Scholar]
  28. TsvankinI.2005. Seismic signatures and analysis of reflection data in anisotropic media . Elsevier.
    [Google Scholar]
  29. WuR.‐S. and ChenL.2006. Directional illumination analysis using beamlet decomposition and propagation. Geophysics 71, S147–S159.
    [Google Scholar]
  30. XieX. and WuR.2002. Extracting angle domain information from migrated wavefield. 72nd Ann. Internat. Mtg, Soc. of Expl. Geophys., 1360–1363.
  31. XuS., ChaurisH., LambareG. and NobleM.S.1998. Common angle image gather: A new strategy for imaging complex media. 68th Ann. Internat. Mtg, Soc. of Expl. Geophys., 1538–1541.
  32. XuS., ZhangY. and TangB.2010. 3D common image gathers from reverse time migration. SEG Technical Program Expanded Abstracts 29, 3257–3262.
    [Google Scholar]
  33. ZhangY., ZhangH. and ZhangG.2011. A stable tti reverse time migration and its implementation. Geophysics 76, WA3–WA11.
    [Google Scholar]
  34. ZhuX. and WuR.‐S.2010. Imaging diffraction points using the local image matrices generated in prestack migration. Geophysics 75, S1–S9.
    [Google Scholar]
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Wide‐azimuth angle gathers for anisotropic wave‐equation migration
Geophysical Prospecting 61, 75 (2013); https://doi.org/10.1111/j.1365-2478.2012.01024.x
/content/journals/10.1111/j.1365-2478.2012.01024.x
/content/journals/10.1111/j.1365-2478.2012.01024.x
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  • Article Type: Research Article
Keyword(s): Angle gathers; Anisotropy; Migration; Wave‐equation

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