Geophysical techniques, such as ground-penetrating radar (GPR), have been successfully used by law enforcement agencies to locate graves and forensic evidence. However, more controlled research is needed to better understand the potential and limitations of this technology in the forensic context. The goal of this study was to determine the potential of GPR using both a 250 MHz and 500 MHz antennae to monitor eight controlled graves with six different burial scenarios using pig carcasses as human proxy cadavers. In addition, a conductivity meter was employed to determine the applicability of using this technology to locate unmarked graves. For the conductivity meter, the data was processed using an EM38 program in conjunction with the SURFER program to display a conductivity contour map of the grid. For the GPR imagery, reflection profile data was processed using the program REFLEXW while horizontal slices were processed using the GPR-SLICE program. Results indicate that the conductivity meter is not a viable option in the detection of clandestine graves when other geophysical tools are available. For the GPR, results indicate that while graves can still be detected after a two-year period, there is a marked decrease in the response, or resolution, of the burial scenarios. Furthermore, burials with grave goods interred along with the carcasses were far more likely to be detected than burials that were interred with no accompanying grave goods. When comparing the performance of the two antennae, the 250 MHz antenna provided increased resolution for large cadavers buried in deep graves.

Ground-penetrating radar (GPR) can be a useful geophysical instrument in the search and detection of clandestine graves in a forensic context. Controlled research in the field of forensic archaeology has demonstrated the applicability of this technology and is vital for improving GPR search methods. The objectives of this research was to evaluate the applicability of GPR, using 250 MHz and 500 MHz antennae, to locate shallow graves containing small pig cadavers in various burial scenarios over a 12 month period. Data was collected on a controlled grid containing six graves at 0.5 m in depth: five graves containing pig carcasses and one control grave. The five graves containing the pig carcasses were devised to test a number of common forensic burial scenarios. The reflection profile data was processed using the computer program REFLEXW. The results demonstrate that the additional grave items did not always increase the detection of the grave for this monitoring period. Further, the low demarcation of the grave containing disturbed backfill illustrated that the hyperbolic reflection features were the result of the pig carcasses and not the disturbed soil. In terms of antenna performance, the 250 MHz data initially provided a higher resolution within the first few months. However, over time the higher detail provided by the 500 MHz data consistently resulted in easily discernable reflections.