Preprocessing

Divergence correction, coherent noise suppression, and CMP sorting were applied to the data before 2-D prestack depth migration. In order to compensate for spherical divergence, we scaled the data in the time axis using a function trace(t)= trace(t)*t. Coherent noise suppression was also applied to eliminate the P-wave and S-wave first arrivals. To eliminate the P-wave first arrival, we applied a linear outer mute to the data. The S-wave arrival was suppressed by applying a 2-D dip filter. Finally, the data was windowed to extract the CMPs with maximum offset coverage and sorted by CMP location. Figure 3 shows the zero-offset section of the resulting data.

 

zero-off
Figure 3 Zero-offset section of the resulting synthetic data. Left: model 1, Right: model 2