Source-receiver prestack depth migration using dreamlets

The dreamlet method adds the time-frequency localization to the frequency domain beamlet method by an additional wavelet transform along the time axis. This method has been applied to shot-profile prestack depth migration and shows great potential on wavefield compression and good imaging quality. However, in shot domain migration, the point source excited wavefield expands during migration on the time-space plane and then increases the amount of dreamlet coefficients and therefore, the computation time. The survey sinking migration not only downward continues the geophones but also the shots. Combining the survey sinking and dreamlet decomposition can achieve higher compression ratio on the whole data volume. For the SEG/EAGE model, the dreamlet survey sinking algorithm is 3 times faster compared with the shot domain dreamlet method with similar imaging quality.