Phase encoding with Gold codes for wave-equation migration

Phase encoding with Gold codes for wave-equation migration

Claudio Guerra and Biondo Biondi

Abstract:

Prestack exploding-reflector modeling aims to synthesize a small dataset comprised of areal shots, while preserving the correct kinematics to be used in iterations of migration velocity analysis. To achieve this goal, the amount of data is reduced by combining the modeled areal data into sets, we call super-areal data. However, crosstalk arises during migration due to the correlation of wavefields resulting from different modeling experiments. Phase encoding the modeling experiments can attenuate crosstalk during migration. In the geophysical community, the most used phase-encoding schemes are plane-wave-phase encoding and random-phase encoding. Here, we exploit the application of Gold codes commonly used in wireless communication, radar and medical imaging communities to phase encode data. We show that adequately selecting the Gold codes can potentially shift the crosstalk out of the migration domain, or the region of interest if a target-oriented approach is used, yielding an image free of crosstalk.

Phase encoding with Gold codes for wave-equation migration