We have used data recorded by a temporary seismograph deployment to infer constraints on the state of crustal stress in the Flinders Ranges in south-central Australia. Previous stress estimates for the region have been poorly constrained due to the lack of large events and limited station coverage for focal mechanisms. New data allowed 65 events with 544 first motions to be used in a stress inversion to estimate the principal stress directions and stress ratio.While our initial inversion suggested that stress in the region was not homogeneous, we found that discarding data for events in the top 2km of the crust resulted in a well-constrained stress orientation that is consistent with the assumption of homogeneous stress throughout the Flinders Ranges. We speculate that the need to screen out shallow events may be due to the presence in the shallow crust of either: (1) small-scale velocity heterogeneity that would bias the ray parameter estimates, or (2) heterogeneity in the stress field itself, possibly due to the influence of the relatively pronounced topographic relief. The stress derived from earthquakes in the Flinders Ranges show an oblique reverse faulting stress regime, which contrasts with the pure thrust and pure strike slip regimes suggested by earlier studies. However, the roughly E-W direction of maximum horizontal compressive stress we obtain supports the conclusion of virtually all previous studies that the Flinders Ranges are undergoing E-W compression due to orogenic events at the boundaries of the Australian and Indian Plates.

New geochronological data combined with existing data suggest that the Neoproterozoic period in Australia was reasonably well mineralised, with two major periods of mineralisation: (1) 850-800 Ma sediment-hosted Cu, unconformity U, and diamond deposits, and (2) 650-630 Ma epigenetic Au-Cu deposits. The early period appears to be associated with extension related to initiation of Rodinia break-up, whereas the geodynamic setting of the latter, more restricted, event is unclear.

In 2009, as part of its Onshore Energy Security Program, Geoscience Australia, in conjunction with the Northern Territory Geological Survey, acquired 373 km of vibroseis-source, deep seismic reflection, magnetotelluric and gravity data along a single north-south traverse from the Todd River in the south to nearly 30 km north of the Sandover Highway in the north. This traverse, 09GA-GA1, is referred to as the Georgina-Arunta seismic line, extends from the northeastern Amadeus Basin, across the Casey Inlier, Irindina and Aileron provinces of the Arunta Region and Georgina Basin to the southernmost Davenport Province. Here, we report the results of an initial geological interpretation of the seismic and magnetotelluric data, and discuss some preliminary geodynamic implications.

Increasingly, positioning applications in hazard assessment, mining, agriculture, construction, emergency, land, utility and asset management have a demonstrated need for centimetre level or better geodetic infrastructure. However, the geodetic infrastructure in the Asia-Pacific, when compared to other geographical regions, can be generally assessed as being sparse, inhomogeneous in accuracy, infrequently realised and difficult to access. Correspondingly, it has become increasingly clear that the Asia-Pacific infrastructure is below the standard that is now available in other regions, such as Europe and the Americas, and it represents a loss in competitive advantage. The Permanent Committee for GIS Infrastructure Asia-Pacific (PCGIAP) and the International Association of Geodesy (IAG) have made some progress in developing the Asia-Pacific geodetic infrastructure; however, it can still be characterised as being a work in progress. In this presentation, we review recent efforts to improve the region's geodetic infrastructure. Specifically, we focus on crustal deformation and show results from the Asia-Pacific component of the International Association of Geodesy (IAG) working group on regional velocity fields, which includes crustal velocity estimates for over 1200 stations. This velocity field incorporates solutions derived from Continuous GPS (CGPS) data, episodic campaign based data and also velocity-only information where precise coordinates are not available. Our combination method, including our approach of incorporating velocity-only information expressed in a variety of reference frames, such as plate-fixed frames, will be overviewed. Finally, we will review the key elements of the Asia-Pacific Reference Frame (APREF) initiative, which will create and maintain a modern regional geodetic framework based on continuous GNSS data.

This abstract discusses the metallogeny of the North Australian Craton and possible links to the assembly and breakup of Nuna, the Paleoproterozoic supercontinent. Before ~1750 Ma, deposits such as VHMS, porphyry Cu and orthomagmatic Cu-Ni deposits formed during the assembly of the NAC as the Kimberley, Numil-Abingdon and Aileron provinces converged and were then accreted onto the NAC. These deposits were formed in arc and backarcs, which generally involved local extension, within overall convergent geodynamic settings. After ~1750 Ma, the metallogeny changed, with deposits such as Broken Hill- and Mt Isa-type Zn-Pb-Ag deposits, unconformity U and iron oxide Cu-Au(U) deposits forming largely during extension associated with the breakup of Nuna.

This Resource Package contains two major products: GA Record 2009/41 and two full-colour, A0-sized map sheets (containing maps at 1:5 million, 1:6 million, and 1:3 million scales) that show the continental extent and age relationships of Archean mafic and ultramafic rocks and associated mineral deposits throughout Australia. These rocks have been assigned to twenty-six Archean Magmatic Events (AME) ranging in age from the Eoarchean ~3730 Ma (AME 1) to the late Neoarchean ~2520 Ma (AME 26). The temporal and spatial relationships of these Magmatic Events in the Pilbara Craton, Hamersley Basin, Sylvania Inlier, Yilgarn Craton, and Gawler Craton are represented on a Time-Space-Event Chart on Sheet 1. An enlarged inset map on this sheet provides in more detail the polygon and line data of the events in the Pilbara Craton, Hamersley Basin, and Sylvania Inlier. Sheet 2 shows the interpreted distribution and characterisation of Archean mafic-ultramafic magmatic rocks in the Yilgarn Craton. In particular, potential new areas of komatiitic rocks under cover that elsewhere in the craton host significant resources of nickel, copper, and platinum-group elements, are highlighted. Other maps on Sheet 2 summarise the nickel resource endowment and crustal neodymium model ages of various geological provinces in the Yilgarn Craton. These map sheets, when used in association with another recently produced map 'Australian Proterozoic Mafic-Ultramafic Magmatic Events (GeoCat 66114; published in 2008)', summarise the temporal and spatial evolution of Precambrian mafic-ultramafic magmatism in Australia. Record 2009/41 (Geocat 69935) is a user guide for the `Australian Archean Mafic-Ultramafic Magmatic Events' map (Geocat 69347). It compiles all the geological and geochronological data that underpins the information portrayed on the map. The Resource Package also contains in addition to the maps and record, a spreadsheet of data that support the maps and a time-series animation summarising all the Archean Mafic-Ultramafic Magmatic Events. <h3>Related products:</h3><a href="https://www.ga.gov.au/products/servlet/controller?event=GEOCAT_DETAILS&amp;catno=69935">Guide to using the Australian Archean Mafic-Ultramafic Magmatic Events Map</a> <a href="https://www.ga.gov.au/products/servlet/controller?event=GEOCAT_DETAILS&amp;catno=70461">Proterozoic Mafic-Ultramafic Magmatic Events Resource Package</a> <a href="https://www.ga.gov.au/products/servlet/controller?event=GEOCAT_DETAILS&amp;catno=66114">Australian Proterozoic Mafic-Ultramafic Magmatic Events: Map Sheets 1 and 2</a> <a href="https://www.ga.gov.au/products/servlet/controller?event=GEOCAT_DETAILS&amp;catno=66624">Guide to Using the Australian Proterozoic Mafic-Ultramafic Magmatic Events Map</a> <a href="https://www.ga.gov.au/products/servlet/controller?event=GEOCAT_DETAILS&amp;catno=69213">Proterozoic Large Igneous Provinces: Map Sheets 1 and 2</a> <a href="https://www.ga.gov.au/products/servlet/controller?event=GEOCAT_DETAILS&amp;catno=70008">Guide to using the Map of Australian Proterozoic Large Igneous Provinces</a>

The western two-thirds of Australia is underlain by Precambrian rocks that are divisible into three Archean to Paleoproterozoic cratons, the West Australian, North Australian and South Australian cratons, separated by Paleoproterozoic to Mesoproterozoic orogens. The temporal and spatial record of Proterozoic rock units and orogenic events documents accretion and assembly of Precambrian, proto-Australia. The Archean Yilgarn and Pilbara cratons were assembled into the West Australian Craton along the Capricorn Orogen during the late Paleoproterozoic (2000 Ma) Glenburgh Orogeny, which then combined with the North Australian Craton along the Rudall Orogen during the 1800-1765 Ma, Yapungku Orogeny. Prior to about 1500 Ma the North and South Australian cratons show a similar geological history and are herein assumed to have evolved as a single entity, termed the North-South Australian Craton. It was bounded throughout most of the late Paleoproterozoic to earliest Mesoproterozoic by subduction zones along its south western and north eastern margins such that much of the craton occupied an upper plate, back arc basin environment. After ~1500 Ma the craton differentiated into the North Australian and South Australian cratons through rotation and lateral translation of the latter, resulting in convergence and collisional suturing with the West Australian craton along the 1345-1140 Ma Albany-Fraser Orogen. The Pinjarra Orogen developed along the margin of the West Australian Craton and records late Mesoproterozoic to Neoproterozoic strike-slip juxtaposition of India within an assembling Gondwana. The Neoproterozoic record of the Terra Australis Orogen, which extends along the eastern side of Precambrian Australia, records rifting and continental breakup within the supercontinent of Rodinia. Australian Proterozoic rocks host significant mineral resources, including world class banded iron-formations in the West Australian craton (Hamersley), and iron oxide copper gold deposits (Olympic Dam), Pb-Zn-Ag systems (Mount Isa and Broken Hill) and uranium deposits in the North-South Australian Craton.

Deep seismic reflection profiles have been acquired and interpreted to better understand the crustal architecture and geodynamic evolution of Australia's geological provinces. Here, we examine some of these profiles to better understand how the Australian continent formed in the Archean and Proterozoic. The 2007 deep seismic reflection survey in North Queensland imaged a major, west-dipping, Paleoproterozoic (or older) crustal boundary, which we interpret as a suture, separating relatively nonreflective, thick crust of the Mount Isa Province in the west from thinner, two layered crust to the east. This boundary is also imaged by magnetotelluric data and 3D inversions of aeromagnetic and gravity data. Farther to the northeast, a second major boundary dips west or southwest, offsetting the Moho and extending below it. It is interpreted as a fossil subduction zone, and is overlain by supracrustal rocks of the Etheridge Province, with ages of ~1720 Ma, which is interpreted as the minimum age of the suture. Seismic profiles in southeast Australia, collected between 1996 and 2009, were combined to provide a cross section of the crust across the Archean-Mesoproterozoic Gawler Craton, Neoproterozoic-Paleozoic Adelaide Rift System, Mesoproterozoic Curnamona Province, Neoproterozoic-Paleozoic Koonenberry Belt and Silurian-Devonian Darling Basin. The transect imaged at least four discrete seismic provinces in the middle to lower crust, all bounded by east-dipping, crustal-penetrating fault zones which extend to the Moho. As the seismic provinces have not been traced to the surface, age control is poor, but they are inferred to be older that the upper crustal rocks above them, most of which are Archean to Mesoproterozoic in age.

Summary of forward gravity and flexure modelling of the New Caledonia Trough to highlight temporal variations in lithospheric rigidity during its evolution.

As part of the Australian Government's Onshore Energy Security Program and the Queensland Government's Smart Mining and Smart Exploration initiatives, deep seismic reflection surveys were conducted in North Queensland to establish the architecture and geodynamic framework of this area in 2006 (Mt Isa Survey; also involving OZ Minerals and pmd*CRC) and 2007 (Cloncurry-Georgetown-Charters Towers Survey; also involving AuScope). Nearly 2300 line km of seismic data were acquired during these surveys. Geochemical, geochronological and complementary geophysical studies were undertaken in support of the seismic acquisition. Overviews of the geology of North Queensland and more detailed descriptions and the results of these surveys are presented in Hutton et al. (2009a, b), Korsch et al. (2009a), Withnall et al. (2009a, b), Henderson and Withnall (2009), and Henderson et al. (2009). The purpose here is to use the new geodynamic insights inferred from these data to provide comments on the large-scale geodynamic controls on energy and other mineral potential in North Queensland. This contribution draws on geodynamic and metallogenic overviews presented by Korsch et al. (2009b) and Huston et al. (2009)