Legacy product - no abstract available

Legacy product - no abstract available

Extended abstract reporting on status of geophysical work being conducted within the Remote Eastern Frontiers project.

The Bight Basin in offshore southern Australia is one of the few remaining major frontier basins in the world. Following the initiation of sea-floor spreading between Australia and Antarctica in the late Santonian, a large deltaic system, known as the Hammerhead Delta, built out into the Ceduna Sub-basin. At the end of the Cretaceous the major influx of siliciclastic sediment ceased. Most of the area of the former delta has been subsequently dominated by marly sedimentation in relatively deepwater. The Hammerhead delta strata extend over an area of over 100,000 km2 and are up to 5000 m thick. Although the Hammerhead Delta built out on a continental margin, the strata have a number of marked differences to strata in well-documented late Cenozoic deltas that built out in such settings. There is a very limited progradation of the Upper Cretaceous shelf break in the Ceduna basin. Instead there is a high preservation of the delta topset strata which are composed predominantly of highstand system tracts with progradational and aggradational parasequence sets. Coal-bearing strata occur landward of the shoreface deposits. In places the parasequence stacking patterns result in large clinoform structures that are up to 700 m in amplitude. The scale of these clinoforms suggest the possibility that they were steep enough for the generation of turbidity currents and consequently there may well be some submarine fan deposits preserved at the base of the clinoforms, landward of the Upper Cretaceous shelf break.

Introduction to a supplementry issue on Cenozoic Continental Sediments in Australia.

This report is a description of velocity data acquired during the summer of 2006/07 on Geoscience Australia's seismic marine reflection, refraction and potential field survey GA302 over the Capel and Faust Basins, Lord Howe Rise. The survey was the final phase of the Australian Government's Big New Oil initiative commenced in 2003 to support acreage release in frontier basins. Previous data over the region are sparsely located, and the present survey will provide explorers with high quality data acquired and processed to modern standards. The Lord Howe Rise is thought to be a continental fragment detached from Australia during the formation of the Tasman Sea. The Capel and Faust Basins are of interest as possible frontier petroleum provinces, and the present work is aimed at improving the confidence of sediment thickness estimation, a critical parameter in evaluating of prospectivity. The study reviews the seismic reflection data from survey GA302, the sonobuoy refraction data acquired, and the stacking velocities from the seismic reflection processing.

Legacy product - no abstract available

This dataset is a pre-release copy of the Australian Geological Provinces Database. The dataset is the best available national coverage of geological provinces as at 1 November 2012. The dataset is not entirely complete for the whole of Australia, and has not undergone complete and rigorous QA/QC. This interim dataset is provided for use only by Geoscience Australia staff and their approved collaborators. The Australian Geological Provinces Database contains descriptions and polygon outlines of geological provinces of the Australian continent and the surrounding marine jurisdictional area. Province types include sedimentary basins, basement tectonic provinces, igneous provinces, and metallogenic provinces. Descriptive attributes include sedimentary, igneous and structural characteristics, age limits, parent and constituent units, relations to surrounding provinces, and mineral and petroleum resources. The province outlines are typically compiled from source data at around 1:1,000,000 scale, which may include outcrop mapping, drilling, and geophysical data. Province boundaries have a spatial accuracy of around 500 metres at best (ie, where constrained by outcrop), but where province boundaries are concealed and are interpreted only from geophysical or drilling data, spatial accuracy may be in the order of 1 km to greater than 10 km. Attribution of province boundaries with information about data source and accuracy is incomplete in this version of the dataset.

In mid 2011, the Australian Government announced funding of a new four year National CO2 Infrastructure Plan (NCIP) to accelerate the identification and development of sites suitable for the long term storage of CO2 in Australia that are within reasonable distances of major energy and industrial CO2 emission sources. The NCIP program promotes pre-competitive storage exploration and provides a basis for the development of transport and storage infrastructure. The Plan follows on from recommendations of the Carbon Storage Taskforce and the National CCS Council (formerly, the National Low Emissions Coal Council). It builds on the work funded under the National Low Emissions Coal Initiative and the need for adequate storage to be identified as a national priority. Geoscience Australia is providing strategic advice in delivering the plan and will lead in the acquisition of pre-competitive data and geological studies to assess storage potential. Four offshore sedimentary basins (Bonaparte, Browse, Perth and Gippsland basins) and several onshore basins have been identified for pre-competitive data acquisition and study.

A recent Geoscience Australia sampling survey in the Bight Basin recovered hundreds of dredge samples of Early Cenomanian to Late Maastrichtian age. Given the location of these samples near the updip northern edge of the Ceduna Sub-basin, they are all immature for hydrocarbon generation with vitrinite reflectance - 0.5% RVmax, Tmax < 440oC and PI < 0.1. Excellent hydrocarbon generative potential is seen for marine, outer shelf, black shales and mudstones with TOC to 6.9% and HI up to 479 mg hydrocarbons/g TOC. These sediments are exclusively of Late Cenomanian-Early Turonian (C/T) in age. The high hydrocarbon potential of the C/T dredge samples is further supported by a dominance of the hydrogen-rich exinite maceral group (liptinite, lamalginite and telalginite macerals), where samples with the highest HI (> 200 mg hydrocarbons/g TOC) contain > 70% of the exinite maceral group. Pyrolysis-gas chromatography and pyrolysis-gas chromatography mass spectrometry of the C/T kerogens reveal moderate levels of sulphur compounds and the relative abundances of aliphatic and aromatic hydrocarbons predict the generation of a paraffinic-naphthenic-aromatic low wax oil in nature. Not enough oom for rest of Abstract