Forensic Applications of Geophysical and Geochemical Methods

Classic forensic investigations are sometimes insufficient to collect all of the potential evidence from a crime-scene, especially if conducted a long-time after, particularly when there are limitations in accessing the site and performing the fieldwork. The described limitations are particularly pronounced in the investigation of war crimes or location of war legacy (unexploded ordnance, buried weapons, mass graves and other potential war-crimes). This paper presents some of the geophysical and geochemical methods and techniques that have been used around the world - the Balkans, the Middle East and the Ukraine, especially in locating secondary and tertiary mass graves and residual military materiel. The described methods include the use of remote sensing methods via airborne or satellite sensors that indicate certain changes on the ground, the use of ground penetrating radar systems, electromagnetic methods, sensors for detecting residual radiation, and geochemical methods of water and soil sampling to collect evidence or locate zones of potential interest. The presented methods outline descriptive alterations in the soil mineralogy, electrical conductivity, occurrences of voids or discontinuities in the ground-penetrating radar data and unusual concentrations of metals or organic substances in water or soil as potential indicators of mass war-crimes or other war legacy.