The OCTek-Australasia study has investigated the rifted margins and offshore basins of Australasia. It covers a region defined by 0°N, 60°S, 90°E & 190°E and joins onto the existing OCTek-Asia-Pacific & OCTek-Indian Ocean studies.
The OCTek-Australasia results will be of interest to those exploring or evaluating the offshore basins of:
• Australian Bight, Gippsland, Bass & Otway Basins,
• Perth, Canarvon, Browse & Bonaparte Basins,
• North Australia / Indonesia including the Timor, Arafura, Solomon & Coral Seas
• New Zealand including Lord Howe Rise and the margins of the Tasman Sea
The primary output from OCTek-Australasia is a comprehensive suite of digital grids for the Australasian region which show:
1 Depth to Moho
2 Total crustal thickness
3 Residual continental-basement crustal thickness
4 Crust and lithosphere thinning/beta factor
5 The residual thermal gravity anomaly at the present-day
The results have been tuned to local breakup/rift ages along the margins and to local crustal reference thickness. They also explore a range of plausible scenarios for the amount of volcanic addition during breakup. As well as presenting the grids in their present-day coordinate framework the crustal thickness grids have been sequentially restored to the end Jurassic, using recently-published stage-poles, for sea-floor spreading in the Coral Sea, Tasman Sea & Southern Ocean.
The suite of digital grids is available for unrestricted use by purchasing companies and institutions and is supported by an atlas of maps, which documents the techniques and data used together with a map-plot from all of the supplied grids.
OCTek-Australasia is based on analysis of data available in the public domain. OCTek gravity inversion is proven technology which has also delivered the OCTek-Atlantic, OCTek-Indian Ocean, OCTek-Asia/Pacific, OCTek-GoM & OCTek-Arctic studies together with confidential results on a proprietary basis from rifted margins worldwide.
A study applying the OCTek gravity inversion methodology to the conjugate South Australia – Antarctic margins has been made available for free public download by Geoscience Australia.