User Manual

Geophysical Survey Systems, Inc. HandyScan
User's Guide
MN70-416 10
Radar Wave Velocity Adjustments
1. Automated processing includes Migration which removes
hyperbolic reflections from the data. Migration requires Radar
Wave Velocity to be set within ½ in/ns of the exact value.
2. The exact velocity is usually not known, thus trial-and-error is
the best way to determine it:
• After first processing, maximize Display Gain and see if
the hyperbolas have collapsed into dots:
Raw Data
Velocity too high Correct Velocity too low
•
Correct velocity – data can be viewed in Depth Slices
• Velocity too high or too low – process again, respectively
decreasing or increasing velocity in
½ in/ns steps until image looks correct.