Southern Geophysical has an EM61-MK2 which is a highly sensitive metal detector connected to a GNSS positioning system. It can locate both ferrous and non-ferrous metal in the subsurface down to several metres. The GNSS data capture enables maps to be created, showing the location of metal objects with an accuracy of +/- 10 cm (when differentially corrected). The most common applications for a EM61 system are locating unexploded ordinances (UXO), underground storage tanks (UST) and utility mapping. Other applications include delineating the extents of landfill, locating archeological items, locating buried wells, and even gold and other ore prospecting.