Geophysical survey can refer to any systematic collection of geophysical data for spatial studies. In archaeology, it most often refers to ground-based subsurface mapping using a number of different sensing technologies. Data collected from the surface can be used for mapping subsurface archaeological features without excavation. Most commonly applied to archaeology are magnetometers, electrical resistance meters, ground penetrating radar (GPR) and electromagnetic (EM) conductivity.
Geophysical survey is also used in marine or underwater archaeology. Magnetometers and a variety of sonar instruments are used for locating shipwrecks and other submerged archaeological features. Typically, data is collected from boats or towed sensors. Although there are broad similarities between underwater and terrestrial geophysics, they have distinct techniques and logistics, and are considered separate disciplines.
The terms archaeological geophysics and geophysical prospection are synonymous with geophysical survey when used in archaeological contexts. The term remote sensing is sometimes also used, but this more properly refers to aerial or satellite imaging or sensing, which is a distinct discipline.
McCoy, Mark D. and Thegn N. Ladefoged 2009 New Developments in the Use of Spatial Technology in Archaeology. Journal of Archaeological Research 17:263-295.