The purpose of the magnetic geophysical technique is to explore the spatial distribution of magnetized rocks and buried ferrous metal objects, based on magnetic measurements made at or near the surface, and then to make a geological or anthropogenic interpretation in terms of the objectives of the investigation. The magnetic method is perhaps the oldest of geophysical exploration techniques (Nabighian et al., 2005).

The magnetic method has become widely used in near-surface geophysics for several reasons (Hansen et al., 2005): (a) buried targets or geological structures of interest often have readily detectable magnetic signatures owing to the high sensitivity of modern magnetometers; (b) the measurements are fast, reliable, and non-invasive; (c) magnetic data are often straightforward to interpret using qualitative and quantitative techniques, especially when large amounts of high-resolution data are acquired over a wide area such that a continuous plan view of the site and its surroundings can be obtained.