Data Collection

Collecting GPR data up a steep slope | Why your hyperbola is off-set

By May 21, 2018 No Comments

Why is your Hyperbola peak off-set when you collect data up a steep slope?

This is because your GPR and the target are at their shortest distance from one another at a different location than directly above your target.

As the GPR is pushed up the slope, the shortest distance and thus the shortest two way travel time of the wave occurs slightly downslope from where the GPR would be directly above the target.

The orientation of the antenna is off and the topography varies even though the GPR is imaging a profile that is “flat”.

To account for this there are a few options.

1) conduct a topographic correction on the GPR data.

2) Use a GPS unit that has a tilt correction (without one, the data will be worse!)

3) possibly consider migrating the data so the distortion of the recorded GPR response is removed and the location of the reflection is placed as close as possible to its actual location.

PS. That is one handsome kid at the end! HAHA!

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