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1 VJ GeoConsultants, 9 Avon Wharf, Bridge Street, Christchurch, BH23 1DJ, UK VJ_Consultants{at}hotmail.com
2 British Geological Survey, Kingsley Dunham Centre, Nicker Hill, Keyworth, Nottingham, NG12 5GG, UK
A wide range of geophysical techniques is applied in forensic investigations where the target objects are frequently buried under ground and are often small in size. These include targets which are only a few centimetres in diameter but located within a large search area are often of several hectares. The application of a specific geophysical technique may be governed by the physical properties of the target object and its local surroundings. However, operational and financial costs are important. Topographical and geological variations or presence of man-made structures may hinder the application of the most cost-effective technique. Additionally, site area, logistics and weather conditions are also important factors.
Generally, to overcome these difficulties it is recommended that forensic geophysics be carried out along conventional geophysical guidelines as used in civil-engineering site investigation. On occasion, departure from these conventional guidelines may be beneficial in that field survey data acquisition can be complemented by simultaneous direct invasive assessment of geophysical anomalies instead of waiting until office reporting has been completed. Three case studies are presented: one relates to a search for a buried metal target located using a scanning magnetometer with simultaneous excavation, and two relate to searches for graves and buried wooden coffins
