Aeromagnetics as an aid to geological mapping—a case history from the Arunta Inlier, Northern Territory

Abstract

Correlation of aeromagnetic and available geological information has allowed extrapolation of geological mapping between isolated basement outcrops in the Jervois Range area of the eastern Arunta Inlier. The superior resolution of computed vertical gradient, in comparison with total field data, aided the delineation of magnetic lithostratigraphic marker horizons, and the subsequent development of a detailed structural model through determination of basement structure and lithology. Rock types in the area include a multiply deformed sequence of metasediments and metavolcanics intruded by basic and acid igneous bodies. Economic concentrations of silver and base metals occur along intense linear magnetic highs associated with magnetite‐chlorite‐garnet host rocks, and the delineation of these host rocks was a primary objective of aeromagnetic interpretation. In situ and laboratory determinations of magnetic susceptibility and natural remanent magnetization (NRM) helped to constrain magnetic interpretation. Re...