Prestack Stolt residual migration for migration velocity analysis
نویسنده
چکیده
This paper presents a method of Stolt residual migration applicable to prestack data. The method’s main merit is that instead of requiring an assumption about the magnitude of the new velocity model to which we want to residually migrate, it only calls for an assumption about the ratio of the reference velocity to the new one. Since the method is, in essence, a Stolt-stretch technique, it inherits Stolt’s speed and convenience. I evaluate the quality of migration, and implicitly the quality of residual migration, using angle-domain common-image gathers. Two examples show that the method can be successfully used in residual migration even when the reference velocity is not constant. An important application of the method is in the area of wave-equation migration velocity analysis.
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