The Stuart Shelf overlies the eastern portion of the Gawler Craton. This part of the Gawler Craton is South Australia's major mineral province and contains the world-class Olympic Dam Cu-U-Au deposit and the recent Cu and Au discovery at Prominent Hill. The Stuart Shelf is several kilometres thick in places. As such, little is known of the crustal structure of the basement, its crustal evolution or its tectono-stratigraphic relationship to adjacent areas, for example the Curnamona Province in the east. There has been much effort applied to advancing our understanding of basement, mainly through the use of potential field data and deep drilling programmes; though drilling has proved very costly and very hit and miss. The Stuart Shelf area needs new data and methods to bring our knowledge of it to the next level of understanding. At a Gawler Craton seismic planning workshop held in July 2001, stakeholders from industry, government, and university stakeholders identified several criteria fundamental to undertaking any seismic survey within the Gawler Craton. These were - Location of seismic traverse across a known mineral system in order to improve understanding and enhance knowledge of the region's mineral systems. Access to surface and/or drill hole geological knowledge to link geology data with the seismic interpretation. Good coverage of potential field data, and Potential for the seismic data to stimulate area selection and exploration in the survey region.

The Palaeoproterozoic to Mesoproterozoic (<1850-<1490 Ma) southern McArthur Basin, Northern Territory, Australia, contains an unmetamorphosed, relatively undeformed succession of carbonate, siliciclastic and volcanic rocks that host the McArthur River (HYC) Zn-Pb-Ag deposit. Seismic reflection data obtained across this basin have the potential to revolutionise our understanding of the crustal architecture in which this deposit formed. These data were collected in late 2002 as part of a study to examine the fundamental basin architecture of the southern McArthur Basin, particularly the Batten Fault Zone, and the nature of the underlying basement. Geoscience Australia, the Northern Territory Geological Survey and the Predictive Mineral Discovery Cooperative Research Centre combined to acquire an east-west deep seismic reflection profile (line 02GA-BT1) approximately 110 km long, commencing 15 km west of Borroloola, and extending westwards along the Borroloola-Roper Bar road to the Bauhinia Downs region (Fig. 1). A short 17 km north-south cross line (02GA-BT2) was also acquired in collaboration with AngloAmerican. The seismic data were acquired through the Australian National Seismic Imaging Resource (ANSIR).

Seismic reflection, seismic refraction and portable broadband data collected within Western Australia's Yilgarn Craton, in particular the Eastern Goldfields Province, are providing detailed images of several of its highly mineralized terranes as well as new insights into the crustal architecture of the region. When the results from these seismic techniques are integrated, the results are providing a better understanding of the structure of the crust and lithosphere beneath the Yilgarn Carton, from the surface to depths in excess of 300 km.

Between October 2008 and February 2009, Geoscience Australia undertook two major surveys off the coast of Western Australia. Areas of interest included the Mentelle and northern Perth Basins, the Southern Carnarvon Basin, the southern Exmouth Sub-basin (Northern Carnarvon Basin) and the Wallaby Plateau. These surveys collected a range of data, including industry-standard seismic reflection data and gravity and magnetic data. In addition to the new data collected, Geoscience Australia has reprocessed existing open file 2D seismic data within the survey area. These data are available for purchase. Please complete the order form on the downloadable information sheet and return to Geoscience Australia.

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

For the last 50 years, Geoscience Australia and its predecessors have been collecting onshore near-vertical-incidence deep seismic reflection data, first as low fold explosive data and more recently as high fold vibroseis data. These data have been used in conjunction with other seismic data sets by various research groups to construct depth to Moho models. The Moho has been interpreted either as a strong reflector per se, or as the bottom of a reflective band in the lower crust. However the amplitude standout of the Moho can be very much dependent on the fold of the data and applied processing sequence. Some low fold explosive data was re-processed by Geoscience Australia to enhance the Moho for comparison with recent vibroseis data, in the Mt Isa province in Queensland, and in the Southern Delamerian and Lachlan Fold Belts in Victoria. Marked improvement was achieved by time-variant band-limited noise suppression of reverberations, as well as by coherency weighted common mid point stacking. Post stack migration can also improve the clarity of the Moho, provided there is enough continuity of the data to avoid migration 'smiles'. An important consideration was amplitude scaling, with a time variant automatic gain control (AGC) employed before stack, and a weighted AGC applied after stack, in order to preserve seismic character. These results demonstrate that processing and acquisition issues need to be understood in order to assess the reflective character of the Moho and indeed to interpret its location.

PowerPoint presentations presented at the NORTH QUEENSLAND SEISMIC AND MT WORKSHOP in Townsville, June 2009.

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.

In 2007, three seismic lines were collected by Geoscience Australia and the Geological Survey of Queensland from Cloncurry to south of Charters Towers via Croydon and Georgetown, and a fourth line by AuScope to the northeast of Mt Surprise. Signals were recorded to ~20 seconds two-way travel time (TWT), which equates to about 60 kilometres in depth. The recent lines are among the latest in a series of deep seismic profiles conducted across Queensland since 1980.

Seismic line 07GA-GC1, described here, forms part of the Isa-Georgetown-Charters Towers seismic survey that was acquired in 2007. The seismic line is oriented approximately northwest-southeast and extends from east of Georgetown in the northwest to south of Charters Towers in the southeast (Figure 1). The acquisition costs for this line were provided jointly by the Geological Survey of Queensland and Geoscience Australia, and field logistics and processing were carried out by the Seismic Acquisition and Processing team from Geoscience Australia. Seven discrete geological provinces have been interpreted on this seismic section (Figure 2). Two of these, the Abingdon and Sausage Creek Provinces, only occur in the subsurface. The upper crustal part of the seismic section is dominated by the Etheridge and Cape River Provinces, but the seismic line also crossed the Broken River Province and the Drummond and Burdekin Basins.