The Australia-wide airborne geophysical survey - accurate continental magnetic coverage

Abstract

Continental-scale merges of Australian airborne magnetic data are only accurate for wavelengths less than about 100 km, due to limitations of survey size and data processing. Wavelengths greater than about 400 km are available from satellite data; thus, there is a ?gap? in the spectrum for intermediate wavelengths between 100 and 400 km (Milligan and Franklin, 2004; Milligan et al., 2004). Geoscience Australia has filled this gap by acquiring new airborne magnetic data as part of the Australian Government?s Onshore Energy Security Program. Intermediate wavelengths are important, for example, for better definition of sedimentary basins for petroleum prospectivity evaluation, for interpreted depths to bottom of magnetic sources in attempts to define the Curie Point isotherm, and for long wavelength regional removal in magnetic modelling.