Processing ground penetrating radar data

Ground penetrating radar (GPR) data are processed using seismic analysis techniques. Processing operations performed include signal saturation, spherical divergence gain recovery, spiking deconvolution, bandpass filtering, velocity analysis, elevation corrections, NMO correction, and f-k migration. As examples we first use 0.5 km lines of 50 MHz and 100 MHz, single-fold data, with a CMP gather from William River delta, Lake Athabaska, Saskatchewan. Next, a 120m, 100 MHz, single-fold line from Ft. Smith, N.W.T. is processed using similar steps. Finally, 100 m of 100 MHz, single-fold data, with a CMP gather, from Brigham City, Utah, are analyzed. Filter bandwidths chosen for the 50 MHz and 100 MHz measurements were 10/20-75/100 MHz and 20/30-150/180 MHz, respectively. Velocity spectra for NMO corrections were determined for William River delta and Brigham City based on CMP gather velocity semblances and interpreted arrivals. Velocities range from 0.3 m/ns to 0.07 ms/ns (air to wet sand respectively). Higher velocity surface statics, caused by dry topography, were corrected for after interpreting shallow arrivals. The Slave River velocities are similar to William River delta suggesting similar r'ock type with higher water saturation and/or lower porosity. Dry sands at Brigham City resulted in radar velocities of 0.14m/ns. Application of seismic processing techniques significantly improved these GPR sections.