Prestack migration velocity analysis using wavefront synthesis
نویسنده
چکیده
Common-reflection-point (CRP) gathers provide important clues in various migration velocity analysis schemes (Al-Yahya, 1987; Etgen, 1990). Conventionally, CRP gathers are obtained by prestack migration of shot records or constant-offset sections. This paper introduces a way to generate a CRP gather for residual velocity analysis using wavefront synthesis imaging. Compared to CRP gathers obtained by other prestack migrations, those obtained by wavefront synthesis imaging provide a better resolution residual velocity panel. As a result, we can easily determine and get more reliable residual velocity, which is very important in inverting it into the true interval velocity of a medium.
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