Drape-Related Problems in Aeromagnetic Surveys: The Need for Tight-Drape Surveys

Aeromagnetic surveys in rugged terrain are often flown relatively high as loosely draped surveys within the operational safety limits of conventional aircraft. The variations in survey elevation inherent in loose-draped surveys give rise to changes in magnetic amplitudes and magnetic resolution that are not related to magnetic sources but are artefacts due to varying depth-to-source.