Ground penetrating radar, or GPR, is a geophysical method that uses radar pulses to image the subsurface, or allow clients to 'see' what is underground.
GeoSearches performs ground penetrating radar services using non-destructive and non-invasive investigative equipment to provide insight into a site's condition for a wide range of clients throughout the world.
With GPR, Geosearches provides insight into a site's condition. Ideally, GPR is performed prior to when a major project begins. It's critical to know what's going on underground before any major development begins. This important step reduces the risk of problems that may arise that could delay schedules, increase design changes, and ultimately increase costs.
Our non-destructive method uses electromagnetic signals in the micro-wave band (UHF/VHF frequencies) of the radio spectrum, and detects the reflected signals from subsurface structures.
GPR uses transmitting and receiving antennas or only one containing both functions. The transmitting antenna radiates short pulses of the high-frequency (usually polarized) radio waves into the ground. When the wave hits a buried object or a boundary with different dielectric constants, the receiving antenna records variations in the reflected return signal.
GPR can be used in a variety of media, including rock, soil, ice, fresh water, pavements and structures. It can detect objects, changes in material, and voids and cracks.
The principles involved in GPR are similar to reflection seismology except that electromagnetic energy is used instead of acoustic energy, and reflections appear at boundaries with different dielectric constants instead of acoustic impedances.
The depth range of GPR is limited by the electrical conductivity of the ground, the transmitted center frequency and the radiated power. As conductivity increases, the penetration depth also decreases. This is because the electromagnetic energy is more quickly dissipated into heat, causing a loss in signal strength at depth.
Higher frequencies do not penetrate as far as lower frequencies, but give better resolution. Optimal depth penetration is achieved in ice, where the depth of penetration can achieve several hundred meters. Good penetration is also achieved in dry sandy soils or massive dry materials such as granite, limestone, and concrete, where the depth of penetration could be up to 15 m. In moist and/or clay-laden soils and soils with high electrical conductivity, penetration is sometimes only a few centimetres.
GeoSearches is a specialists company in non-destructive investigation and engineering geophysics using advanced methods including ground penetrating radar (GPR) to survey geotechnical and environmental, buildings, structures, and engineering infrastructure, including roads, railways and airports.
Clients consider what we offer a smart investment; knowing more about site conditions up front reduces the risk of facing problems mid-project when delays in schedule or changes in design can result in escalating delays and costs.
Contact us to set up your initial consultation with one of our Geophysical Specialists.