Depth Velocity Model Building and Imaging in the Presence of Shallow Velocity Anomaly Effects

E034 Depth Velocity Model Building and Imaging in the Presence of Shallow Velocity Anomaly Effects E. Blias* (VSFusion) SUMMARY A method of compensation for the presence of discrete shallow velocity anomalies has been developed. When the first breaks approach fails for any reason (first breaks are hard to pick there is a shallow low velocity layer permafrost etc) the only seismic information available is deep reflections. Shallow velocity anomalies cause large lateral variations in stacking velocities increasing with depth. Dix’s formula gives us interval velocities in 1-D media. In many cases the 1D assumption does not work especially when we