What is airborne geophysics and why it accelerates mineral exploration
Fabrício Santos · July 15, 2026 · 5 min
Airborne geophysics is the set of techniques that measure the physical properties of rocks using sensors mounted on aircraft — fixed-wing planes or drones. Instead of walking an area meter by meter, an airborne geophysical survey covers large regions in a few hours of flight, recording subtle variations in the magnetic field, the natural radiation of the ground and, in some cases, the density and electrical conductivity of the rocks.
Why measure from the air
Every rock type responds differently to physical properties. A magnetite-rich body, for example, locally distorts the Earth's magnetic field; granitic rocks tend to emit more gamma radiation associated with potassium, thorium and uranium. By mapping these responses at a regional scale, the geologist sees lithological contacts, faults, hydrothermal alteration zones and possible mineralized bodies without removing a single gram of soil.
This subsurface view is especially valuable in areas covered by dense vegetation, thick soils or recent sediments, where traditional geological mapping finds few outcrops.
What a typical survey delivers
An airborne geophysical survey usually combines two main methods:
- Magnetometry, which records variations in the magnetic field and helps outline structures and bodies with a magnetic contrast.
- Gamma-ray spectrometry (radiometrics), which measures natural radiation and discriminates lithologies by their potassium, thorium and uranium signature.
From this raw data, a family of derived maps is produced — magnetic anomaly, analytic signal, tilt derivative, radiometric ratios, RGB ternary image, among others — each highlighting a different aspect of the geological framework.
The bottleneck: turning data into decisions
Public airborne geophysical data is abundant in Brazil, released by institutions such as the Geological Survey of Brazil (SGB/CPRM). The historical challenge was never a lack of data, but the time and expertise required to process it: downloading files, organizing databases, applying filters one by one in expensive software and cross-referencing everything with geology and mineral occurrences. This work can take days for a single area.
It is precisely this bottleneck that automation attacks. By standardizing processing and automatically integrating official databases, what took days is delivered in minutes — freeing the geologist for what really matters: interpreting and prioritizing targets.
Where Lithogeo comes in
The Lithogeo platform automatically processes the airborne geophysical data already available and integrates it with geology, terrain and mineral occurrences, delivering a report-ready map package. In upcoming articles, we detail each method and show how to read the main products generated.
This content is educational and introductory. For specific applications, always seek the analysis of a geoscience professional.