The latest index of Australian airborne geophysical surveys has been released, and includes details of all available open-file surveys completed to date by the Australian, state, and territory governments as well as the private sector.

The geophysical data created by these surveys is used to generate 3D models of the sub-surface geology, which can then be used to support decision making related to the development of resources, management of the environment, and the well-being of communities in the survey areas.

The Index of Airborne Geophysical Surveys (14th Edition) now includes details on surveys that have acquired more than 34.9 million line kilometres of mainly magnetic intensity and gamma-ray spectrometric data. It also includes details on surveys where land elevation data are derived from GPS recordings made during airborne magnetic and gamma-ray spectrometric surveys, with electromagnetic data also available for some areas.

Geophysical survey data measures variations in the Earth’s physical properties caused by changes in the physical properties of rocks in the sub-surface, such as magnetisation, natural radioactivity and electrical conductivity.

Since 1999, Geoscience Australia and State and Territory Geological Surveys have contracted airborne geophysical companies to undertake surveys, either separately or as part of joint projects. Geoscience Australia’s predecessors the Australian Geological Survey Organisation (AGSO) and the Bureau of Mineral Resources (BMR) used their own aircraft between 1951 and 1999. Airborne survey index information was first published in 1977 by the BMR.

The open-file airborne geophysical data included in the National Airborne Geophysical Database are available free via the Geophysical Archive Data Delivery System on the Australian Government Geoscience Portal. This includes all open-file geophysical surveys completed prior to this latest edition.

The Index of Airborne Geophysical Surveys (14th Edition) is available, for free, online now.