Tailored drone-magnetometer design for geothermal exploration

Geothermal fields, often nestled in mountainous regions with challenging topography and dense vegetation, can be difficult to access for direct ground measurements. To overcome these obstacles, the magnetic method offers a viable geophysical approach for geothermal exploration. Leveraging advanced technology, Unmanned Aerial Vehicles (UAVs) equipped with magnetometers can provide faster, more accurate, and efficient magnetic mapping, making them an invaluable tool for achieving operational targets. This article presents the design of a drone magnetometer using a custom-built UAV for magnetic mapping in geothermal fields. The UAV is specifically designed with a large payload capacity (6–8 kg) and extended flight duration (> 60 minutes). It is equipped with a 3-Axis Fluxgate Magnetometer FGM3D/100 from Sensys, which has a measurement range of ± 100 µT. The designed system was validated using a PPM scalar magnetometer from GEOTRON, with highly satisfactory results, suggesting it is well-suited for practical geomagnetic mapping in geothermal fields.