Modern, professional, GPR equipment operated by specialists in subsurface imaging
We can “see” shallow or deep. We use Geophysical Survey Systems’ state of the art SIR3000 and antennas ranging from 100MHz to 1500MHz depending upon the job requirements. With GPR we can image rebar and PT cable in concrete; graves and spaces between them in cemeteries; voids, layering, soil horizons and shallow bedrock topography. When requested and where practical, we link the GPR with a Trimble GeoXT GPS platform for geo-positioning our GPR projects. For environmental studies, we have fiber-optic cameras to investigate the condition of voids, tunnels and pipes found with GPR and can use seismic to identify bedrock topography, fractures and rock properties. We can undertake electromagnetic, magnetic and electrical resistivity studies to assess ground water depth, fractures, and soil moisture when requested.
- GPR Equipment: GSSI Sir 3000 and antennas operating in the range from 100MHz to 1500MHz.
- GEM 300 Multifrequency electromagnetic profiler
- EM31 terrain conductivity mapping
- MetroTech 810
- See Snake fiber optic cable
- Full Suite of software to analyze data and present results. We use GPR-SLICE GPR Imaging Software.
How GPR Works
Ground penetrating radar works by sending high frequency radio waves into the ground from an antenna that transmits energy and receives reflections. As the antenna is pushed across the ground surface from a start to end point, some energy bounces off objects and debris in the ground and the reflections that return to the antenna are recorded. A single line of recorded radar data captures reflections from beneath the antenna. Many lines of data collected parallel to one another are required in order to image features buried in the ground. The spacing between parallel lines is determined by the size of the objects being investigated. For buried caskets, a line separation of 2 feet is sufficient to record child and adult cast iron caskets.
There are two phases of GPR work: data collection, and processing the collected data. These two phases produce maps of where anomalies (disturbances in the ground) are located. Both phases require attention to detail and must be done correctly to produce credible results.