Seismic survey reveals new resource potential

24 November 2008


Sectional images of line 07GA-IG1 showing magneto-telluric data, uninterpreted seismic data, interpreted seismic data, and interpreted enlargement showing the Millungera Basin. In all sections, vertical is approximately equal to horizontal - click to enlarge.

The survey, which was carried out in the Cloncurry-Croydon region by Geoscience Australia in collaboration with the Geological Survey of Queensland, led to the discovery of two major sutures, or fault zones which mark the boundaries of a previously unknown geologic province.

This province forms the basement to the Millungera Basin, which also was unknown prior to the survey. The new province, which is about 100 kilometres east of Cloncurry and extends over 15 000 square kilometres, is concealed by thinner, younger rocks and is considered to have potential for geothermal energy and possibly petroleum resources.

The eastern boundary of the new province is particularly unusual. It has west-dipping seismic reflections in the mantle associated with a step that increases by around six kilometres the depth of the Moho. Elsewhere in the world, similar features have been interpreted as fossilised subduction zones which provide a unique window into ancient tectonic processes.

Interpretations of the seismic data also revealed that the western sutures show similarities to the geological settings of the world-class Olympic Dam copper-gold-uranium deposit in South Australia.

The discoveries were made as part of Geoscience Australia's $59 million Onshore Energy Security Program and the Queensland Government's Smart Mining and Smart Exploration initiatives to provide pre-competitive data to the mining and explorations industries.

Topic contact: media@ga.gov.au Last updated: October 4, 2013