Aero Magnetics Survey

Aeromagnetic surveys are a typical type of geophysical survey carried out by using a magnetometer on a ship or being pulled behind an airplane. The principle is similar to magnetic surveys conducted with a handheld magnetometer, but allows a much larger area of ​​Earth's surface to be covered quickly for regional surveillance. Aircraft typically fly in patterns such as grids with height and line spacing determining data resolution (and survey costs per unit area).

As the plane flies, the magnetometer measures and records the total intensity of the magnetic field on the sensor, which is a combination of the desired magnetic field generated on Earth as well as minor variations due to the temporal effect of the ever changing solar wind. and magnetic field of the survey aircraft. By reducing the effects of the sun, regional, and aircraft, the resulting aeromagnetic maps show the spatial distribution and abundance of magnetic minerals (most often iron iron oxide minerals) at the top of the Earth's crust. Because different types of rock differ in their magnetic mineral content, magnetic maps allow visualization of the geologic structure of the upper crust below the surface, especially the geometry of the spatial body of the rock and the presence of errors and folds. This is particularly useful where the bedrock is obscured by surface, soil or water sand. Aeromagnetic data was once presented as a contour plot, but is now more commonly expressed as a thematic picture (color) and a shady computer producing pseudo-topographic images. The hills, valleys and valleys are clearly referred to as aeromagnetic anomalies. A geophysicist may use mathematical modeling to infer the shape, depth and properties of the body of the rock responsible for the anomaly.

Aircraft are usually used for high-level surveillance surveys in soft terrain, and helicopters are used in mountain areas or where more detail is needed.