Why GPR loses depth in clay and wet soil, and how progressive scanning gets around it
Depth is set by the ground, not the radar. Here is the fix.
Where the signal goes
Radar energy is absorbed as it travels through the ground, and how fast depends on the soil. Dry sand and gravel absorb little, so the signal reaches many feet down. Clay, especially wet clay, absorbs a great deal; saturated clay can swallow the signal within a foot or two. No antenna design changes that physics.
Why a bigger radar is not the answer
Lower frequencies reach deeper but see less detail, and more power runs into regulatory limits and still fades in clay. Every surface GPR, from any maker, has a practical depth limit set by the soil on that site.
Progressive scanning
The GroundScope GSX1000 is built to go down with the dig. Scan the surface and dig what it cleared. Lift the radar core out of its sled, set it in the trench, and scan again. Each pass clears the next layer before the bucket takes it. The scan is always looking at fresh ground just ahead of the excavation, so the soil no longer sets the depth.
Trench mode fits trenches and auger holes from 18 inches wide. The handle plugs into the top of the housing, and the cord stays connected.
What this means for the crew
A surface scan is the first check, not the last. In difficult ground, plan to scan at each lift. It adds seconds per pass and removes the depth question.
Common questions
How deep does the GSX1000 see?
Zero to about five feet in typical soil from the surface. Scanning from inside the trench extends that to the depth of the dig.
Does wet weather stop scanning?
No. The unit is sealed to IP65. Wet ground reduces depth from the surface, which is where trench scanning helps.