We present a method for automatically obtaining a detailed, accurate representation of a top-salt velocity model contrast, starting from a crude initial top-salt interpretation. The method is based on the analysis of time-shift gathers obtained in a salt-flood velocity model with RTM. It uses the fact that source- and receiver-side wave fields back-scattered at the velocity contrast during the RTM process result in an image contribution in time-shift gathers that interferes at the reflection point with the image contribution due to the incident wave fields. The time-shift value at, or directly above, the top-salt interface at which back-scattering of the source- and receiver-side wave fields occurs is automatically picked. The resulting time shifts are filtered and converted into a detailed depth update of the top salt horizon. The process is repeated until convergence. We demonstrate the method on a 2D synthetic data example with a complex top-salt interface.


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  1. Billette, F., and S.Brandsberg-Dahl
    , 2005, The 2004 BP velocity benchmark: 67th Annual Conference & Exhibition, EAGE, Extended Abstracts, B305.
    [Google Scholar]
  2. Etgen, J. T., I.Ahmed, and M.Zhou
    , 2014, Seismic Adaptive Optics: 84th Annual International Meeting, SEG, Expanded Abstracts, 4411–4415
    [Google Scholar]
  3. Hu, C., U.Albertin, and K.Osypov
    , 2015, Subsalt image enhancement by automatic picking top of salt using RTM time-lag gathers and surface warping, 85th Annual International Meeting, SEG, Expanded Abstracts, 4054–4058
    [Google Scholar]
  4. Sava, P. and S.Fomel
    , 2006, Time-shift imaging condition in seismic migration: Geophysics, 71, S209–S217
    [Google Scholar]
  5. Xie, J., W.Whiteside, and B.Wang
    , 2012, Remove RTM Artifacts Using Delayed Imaging Time Gathers, 82nd Annual International Meeting, SEG, Expanded Abstracts, 1–5
    [Google Scholar]

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