Aeromagnetic survey

The principle is similar to a magnetic survey carried out with a hand-held magnetometer, but allows much larger areas of the Earth's surface to be covered quickly for regional reconnaissance.

The aircraft typically flies in a grid-like pattern with height and line spacing determining the resolution of the data (and cost of the survey per unit area).

Aeromagnetic data was once presented as contour plots, but now is more commonly expressed as thematic (colored) and shaded computer generated pseudo-topography images.

Aeromagnetic surveys were first performed in World War II to detect submarines using a Magnetic Anomaly Detector attached to an aircraft.

The market of unmanned aerial systems is exponential development, so the arrival of these technologies in some niches was inevitable including geophysical surveys.