paul@sep.stanford.edu

Prestack Stolt residual migration

Paul Sava* Stanford University

Biondo Biondi Stanford University

paul@sep.stanford.edu

When is the velocity “correct”?

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Motivation

• Why residual migration?• image enhancement

• Why prestack?• migration velocity analysis• illumination

• Why Stolt residual migration?• fast, robust

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Agenda

Prestack residual migration

Examples

Motivation

Methodology

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Prestack Stolt residual migration

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Prestack & post-stack

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paul@sep.stanford.edu

Prestack Stolt residual migration

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Fourier-domain global action

depth

Velocity

ratio (

Velocity ratio (no explicit velocity)Prestack

paul@sep.stanford.edu

Agenda

Prestack residual migration

Examples

Motivation

Methodology

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correct velocityincorrect velocity

Example 1

residual migration

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Example 2

11 1

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Example 3illumination or velocity?

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original imageresidual moveoutresidual migration

Example 3: comparison

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before residual migrationafter residual migration

Example 3

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Summary

• Residual migration– Fourier-domain method– Prestack– No explicit knowledge of velocity

• Analogous to Stolt migration• fast and robust• global action