Kirchhoff prestack time migration assumes 2-D energy scattered from a point is spread evenly on a surface known as Cheop's pyramid in the prestack data volume. The scatter points may be combined to construct a reflector, and the Cheop's pyramids from each scatter point reconstruct the reflection energy. The reconstructed energy is no longer distributed evenly across the surface of a given Cheop's pyramid but is instead concentrated in a localized band. When collected into common scatter point (CSP) gathers, concentrated data from a scatter point with a given dip will be distributed along a hyperbola defined by the migration imaging velocity.
The concentration of energy on Cheop's pyramid and the distribution of energy in the corresponding CSP gather will be presented for horizontal and dipping data.
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