Ground Penetrating Radar

Ground Penetrating Radar (GPR) functions by emitting electromagnetic pulses into the ground using a transmitting antenna. These pulses reflect off subsurface objects or interfaces between different materials where a contrast in dielectric constants exists. The receiving antenna then captures these reflected signals and displays them in real-time on the screen.

GPR signals can penetrate depths of up to 60 meters in materials with low electrical conductivity, such as dry sand or granite. However, in materials with high conductivity like clay or shale the signals may be significantly weakened or absorbed, thereby reducing the penetration depth.

The depth of investigation also depends on the frequency of the GPR antenna. Lower frequency antennas enable deeper penetration but offer lower resolution. These are commonly used for geological studies, such as detecting sinkholes, fractures, or locating large, deeply buried objects.

Antennas with higher frequencies provide high-resolution data but are limited to shallower depths (typically 0 to 10 meters). These are suitable for examining surface soils and for detecting both small and large shallow buried features, such as utility pipes, cables, and reinforcement bars in concrete.