seismic · electrical · electromagnetic · magnetic · microgravity · ground penetrating radar · radiometric · nuclear magnetic resonance · thermal
The success of all geophysical methods relies on there being a measureable contrast between the physical properties of the target and those of the surrounding medium.
The properties used are typically density, elasticity, magnetic susceptibility, electrical conductivity, and radioactivity.
Knowledge of the material properties likely to be associated with a target is thus essential to guide the selection of the correct method to be used and to interpret the results obtained.
Often a combination of methods provides the best means of solving complex problems.