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  • The offshore Vlaming Sub-basin located in southern part of the Perth Basin is a Mesozoic depocentre estimated to contain over 12 km of sediments. It has several potential source rock intervals, good reservoir and seal pairs and an active petroleum system. A lack of exploration success in this basin has been re-assessed by analysing fault reactivation and signs of hydrocarbon seepage. Recently completed study integrated structural mapping, with analysis fluid inclusion results. New data and interpretations showed that a number of synrift faults remained active for at least 5 - 7 Ma after the breakup, which corresponds with the main period of hydrocarbon generation and expulsion in the Vlaming Sub-basin. Fault planes and zones of weakness associated with active faults provided migration pathways for generated hydrocarbons, therefore no accumulations were formed at these locations. Many previously identified plays reply on the post-rift South Perth Shale for a seal. Our analysis suggests that many faults were reactivated after the deposition of the South Perth Shale, with some showing signs of present-day reactivation. The study provides insight into location of leaky structures and areas with potentially valid plays in the Vlaming Sub-basin.

  • L203 13GA_EG1 seismic line acquisition parameters and an overiew of the main data processing steps.

  • A preliminary assessment of the petroleum potential of Australia's offshore central eastern margin, between Cape Howe and the southern boundary of the Great Barrier Reef Marine Park.

  • Expedition 369 planned for September 2017 will drill several holes on the Naturaliste Plateau and the adjacent Mentelle Basin off southwest Australia. The unique tectonic and paleoceanographic setting of this region offers an outstanding opportunity to investigate a range of scientific issues of global importance, especially rapid climate change during the onset of the Cretaceous hot greenhouse. Equally fascinating and poorly documented is the sedimentary, tectonic and geodynamic history of the region. Expedition 369 provides a unique opportunity to study how the Earth's climate and oceans responded to elevated levels of atmospheric CO2 and the role of local tectonic events in the onset of anoxic conditions.

  • The development of regional tectonic models not only aids geological understanding but can be used to identify potentially metallogenically-important geological terranes, particularly when a minerals system approach is used. A downside to this approach, however, is that incorrect geodynamic models can lead to misleading conclusions, and it is imperative that a number of working models be assessed. For example, many geodynamic models for the early Paleozoic Tasman Element of eastern Australia are based largely on the Delamerian and Lachlan orogens in south-eastern Australia, with lesser consideration of what may have been happening further north in the Mossman and Thomson orogens. This is unfortunate, as in north Queensland the entire Paleozoic evolution of eastern Australia is largely superimposed within one narrow area, close to Paleo- and Mesoproterozoic rocks of the Georgetown-Coen region (i.e., the old Rodinian margin). This is in distinct contrast to the present-day width (to 1000 km) of the Delamerian and Lachlan orogens in southern Australia - a feature which has been the continuing focus of many studies and which has driven many tectonic models for the region. It is also evident that just as metallogenic studies benefit from tectonic models, a better metallogenic understanding provides additional constraints and understanding for tectonic models. In this paper we discuss features that characterise the early evolution of the Lachlan orogen (particularly the Delamarian and Benambarn tectonic cycles), particularly in consideration of data from northern part of the orogen and the distribution and timing of mineral systems.

  • The geology of the southern Thomson Orogen is poorly understood due to extensive cover of Mesozoic and Cenozoic sedimentary basins and regolith. Small outcrops of the southern Thomson Orogen are exposed along the Eulo Ridge (south Qld) and in the southwest near Tibooburra (NSW). Cover is of varying thickness and overlies a pre-Cretaceous-age palaeotopography with much greater relief than the present-day landscape. Proximal to these regions the thickness of cover is estimated to be < 200 m, which is within current economic exploration and mining depths. The southern Thomson Orogen is true 'greenfields' country. Although the mineral potential of the region is largely unknown, the north-eastern Thomson Orogen is well mineralised (e.g., Thalanga and Charters Towers), as is the Koonenberry region to the southwest (e.g., Tibooburra and Milparinka) and the Lachlan Orogen to the south (e.g., Cadia and Cobar). In order to encourage exploration investment in the southern Thomson Orogen, Geoscience Australia (GA), the Geological Survey of Queensland (GSQ) and the Geological Survey of New South Wales (GSNSW) have commenced a three-year collaborative project (the Southern Thomson Orogen Project - STOP) to synthesise existing and collect new pre-competitive geoscience data. The first stage of the project has synthesised existing geology and geophysics (magnetic, gravity and seismic data) to produce a new, seamless solid geological map of the Paleozoic basement across the state border. This is supported by the collection of new isotopic age dating samples from industry drill holes in the region to assess magmatic, metamorphic and mineralisation ages. These new samples will also be used to assess the potential mineral systems present in the southern Thomson Orogen, the prospectivity of the region and to conduct a gap analysis. Secondly, new surface geochemical samples have been collected over the Eulo Ridge to complement other low sampling density samples collected by the Cooperative Research Centre for Landscape Environments and Mineral Exploration (CRC LEME) and as part of the National Geochemical Survey of Australia (NGSA). Early results from these samples highlight the use of surface samples and weak acid digestion to map the distal dispersion footprints of large mineralisation systems and bedrock terrains. The third stage of the project is to collect new geophysical data across the region to assess the depth of cover over the Eulo Ridge and to map lithospheric architecture. This involves collecting new airborne electromagnetic (AEM), gravity and magnetotelluric (MT) data. To date, 4267 line kilometres of new AEM data have been collected in the area. Over the Eulo Ridge, 3352 line kilometres was collected as a regional survey with east-west flight lines of 5000 m line spacing. This survey was designed to map the basement-cover interface across the Eulo Ridge, map basement geological units and potentially locate conductive targets in the basement. Two AEM traverses were also collected: from Gongolgon (NSW) to Thargomindah (Qld); and from Louth (NSW) to Eulo (Qld), of 915 total line kilometres. These two traverses are complemented by the acquisition of ~3550 new gravity stations at 333 m station spacing and ~200 new broadband MT stations at 5 km station spacing (in progress November - December 2014). The combined AEM, gravity and MT datasets will be used to model the lithospheric architecture of the southern Thomson Orogen and to reassess the Thomson Orogen-Lachlan Orogen boundary. A program of detailed audio frequency MT (AMT) acquisition is also underway to map geological structures across the Eulo Ridge in Queensland. The combined results will be synthesised and integrated into a precompetitive geoscience data package to encourage exploration investment. Interim products and datasets will be released throughout the project, with the final results delivered to industry in 2016.

  • Until recently the primary source of information for generating whole of government situational awareness during a crisis to support national level decision making was compiled from a range of text-based reports supplied by stakeholders. For example, information about the location and extent of a crisis was assembled in paragraphs or lists leaving the reader to construct their own 'mental map' to interpret the nature of a crisis. Incorporating map-based products to illustrate the location content described in these reports would provide a new spatially based contextual framework to assist the consistent interpretation of crises and enhance product delivery. The Australian Government Crisis Coordination Centre (CCC) was launched in October 2011. Since then, three government agencies have worked together to develop, test and implement a spatial capability to better support a coordinated response to disasters requiring Australian Government assistance. Geoscience Australia (GA), the Australian Geospatial-Intelligence Office (AGO), and the Attorney-General's Department (AGD) have been working together to establish a spatial capability in the CCC which delivers consistent spatial products to supplement and enhance all-hazards reporting, executive briefings, and incident and situation awareness reports. The capability has been tested over the past two years on multiple flood, fire and cyclone events. The critical success factors underpinning the effectiveness of the new spatial capability in the CCC is much deeper than simply the supply of maps - it consists of in-house and remote spatial and natural hazard support provided by GA liaison officers; technical support through the AGO; collaboration with state and territory spatial emergency services; the implementation of agreed standards; and the integration of existing commonwealth, state and territory web services culminating in the development of the National Situation Awareness Tool - NSAT.