In April 2015 Geoscience Australia (GA) acquired 908 km (full-fold) Gippsland Southern Margin Infill 2D Seismic data using Gardline's M/V Duke. The survey is designed to better resolve the Foster Fault System and provide better integration between the GDPI10 survey and the existing surveys in the central deep. The data underwent pre-stack depth migration with a deghosting algorithm during processing. The dataset includes intermediate processing products as well as final preSTM and preSDM and associated velocities.

Several belts of poorly-exposed igneous rocks occur in the Grampians-Stavely Zone of western Victoria, close to the interpreted Cambrian east Gondwana continental margin. Previous geochemical studies on the outcropping igneous rocks around Mount Stavely, Mount Dryden and in the Black Range have recognised characteristics similar to those found in modern magmatic arcs. These rocks are collectively considered to form part of a single Middle to Late Cambrian arc system, referred to as the Stavely Arc. While outcropping examples of the Stavely Arc magmas are well studied, the character of other (likely) arc-related rocks imaged by magnetic data beneath recent, thin cover has remained enigmatic. New geochemical data from a recent stratigraphic drilling program, together with analysis of rocks from government and industry drill holes has allowed for a more complete understanding of the Stavely Arc package. A range of rock associations have been recognised, including low-Ti boninite-like rocks, back-arc-related tholeiitic rocks, adakitic porphyry intrusives, serpentinites, and highly-depleted mafic to intermediate volcanics and intrusives. The majority of arc-related rocks comprise low- to high-K calc-alkaline basalt, andesite, dacite, and geochemically-related quartz diorite, which display similar N-MORB-normalised trace element patterns, LREE-enriched REE patterns and moderately evolved to weakly juvenile Nd isotopic compositions (Nd 500 Ma = -3.95 to +0.46). High-Al basalts intersected during stratigraphic drilling also show weakly-developed calc-alkaline compositions. However, these are distinguished from the other calc-alkaline rocks by higher Al2O3, N-MORB-like trace element patterns, relatively flat REE patterns and much more juvenile Nd isotopic compositions (Nd 500 Ma = +4.73 to +6.33). High-Al basalts are spatially associated with boninites intersected by mineral exploration drilling. The earliest geochronological evidence for Stavely Arc magmatism is provided by an isotopically juvenile felsic intrusive with an interpreted arc-related origin dated at ~510 Ma. This age is synchronous with tholeiitic dolerite from the western Grampians-Stavely Zone interpreted to have been emplaced in a back-arc extensional setting. Available ages for volcanic rocks of the Stavely Arc are only known from the Mount Stavely Belt, and show that arc magmatism reached maturity around ~505-500 Ma. Overall geochemical systematics suggest that the majority of calc-alkaline rocks of the Stavely Arc have affinities with modern island arcs with (limited) continental crust involvement. It is unlikely that the thickness of any pre-existing Precambrian crust was great, given the Nd isotopic compositions and lack of inherited Mesoproterozoic or older zircons. In comparison, the more juvenile isotopic characteristics, weakly-developed subduction-related features, and spatial association with boninites of the high-Al basalts are more consistent with a more primitive arc setting, and may represent an (early?) phase of Stavely Arc magmatism in which there was insignificant crustal involvement. Similar geochemical characteristics, ages, and inferred tectonic setting are consistent with the Stavely Arc forming part of a larger Middle to Late Cambrian arc system that also includes the Mount Wright Arc in New South Wales and the Jamison Volcanic Group (Selwyn Block) in central Victoria.

This presentation will provide an overview of geological storage projects and research in Australia.

Compilation of new and existing data can be used to show systematic variations in initial ore-related Pb isotope ratios and derived parameters for the Lachlan and Delamerian orogens of southeast Australia. In addition to mapping tectonic boundaries and providing genetic context to mineralising processes, these variations map mineralised provinces at the orogenic scale and can provide vectors to ore at the district scale. In New South Wales and Victoria, mapping using a parameter termed the 'Lachlan Lead Index' (LLI), which measures relative mixing between crustal- and mantle-derived Pb using the curves of Carr et al. (1995, Economic Geology 90:14671505), clearly demarcates the boundary between the Eastern and Central Lachlan provinces, and seems to identify boundaries between zones within the Western Lachlan Province of Victoria. The LLI also maps the extent of the isotopically juvenile Macquarie 'Arc' in New South Wales. However, rocks in the Rockley-Gulgong Belt, initially mapped as part of the Macquarie Arc, have a more evolved isotopic character, suggesting that these rocks are not part of the Macquarie Arc. This interpretation supports recent mapping that casts doubt on the attribution of this belt to the Macquarie Arc (Quinn, et al., 2014, Journal of the Geological Society of London 171:723736). The LLI has also identified small exposures of Ordovician volcanic rocks, well removed from the main Macquarie Arc, as possible correlates to this arc, with potential to host porphyry and epithermal deposits. Metallogenically, porphyry Cu-Au deposits in the Macquarie Arc are characterised by juvenile Pb. In contrast, Sn and Mo deposits in the Central Lachlan Province (i.e., the Wagga tin belt) are characterised by highly evolved Pb even though these deposits formed over 30 million years. Moreover, the Pb isotope data suggest that the original interpretation that copper deposits in the Girilambone district are volcanic-associated massive sulfide deposits was correct and that these deposits formed in a back-arc to the Macquarie Arc at ~480 Ma. In the Mount Read Volcanics of western Tasmania, all deposits appear to cluster along the same growth curve. However, when divided according to age (i.e., Cambrian (~500 Ma) versus Devonian (~360 Ma)), spatial patterns are visible in 206Pb/204Pb data. For Cambrian deposits 206Pb/204Pb decreases overall to the southeast, although low values are also present in the far south (i.e., Elliott Bay) and northeast. The most highly mineralised central part of the belt seems to be broadly associated with the zone of highest 206Pb/204Pb. Variations in 206Pb/204Pb for Devonian deposits broadly mimic the patterns seen for the Cambrian deposits. More importantly, a district-scale pattern in 206Pb/204Pb is present in the Zeehan district. Isotopically, the Sn-dominated core of the Zeehan district (e.g. Queen Hill and Severn deposits) is characterised by high 206Pb/204Pb, which decreases outward into the Zn-Pb-Ag-dominated peripheries. Lead isotope distribution patterns can potentially be used as an ore vector in this and other intrusion-centered mineral systems.

Based on calcareous nannofossil evidence, the stratigraphically important interval with Hantkenina (H.) alabamensis primitiva Cushman and Jarvis in the upper Eocene of southern Australia is placed high in the foraminiferal Zone P. 16 of the tropics; previously it was correlated with the upper part of Zone P. 15. Consequently, the upper Eocene sediments above this interval at Browns Creek (Otway Basin) and Blanche Point (St Vincent Basin) are considered to represent an expanded section, with a very high rate of sedimentation. This is consistent with, and probably helps understanding of, the disjunct vertical distribution of several foraminiferal species reported previously in these sediments - particularly at Browns Creek.

The Otway Basin is a rifted margin basin containing a sequence of Mesozoic to Tertiary sediments up to 7500 m thick, resting on a Palaeozoic metasedimentary and granitic basement. Hydrocarbon shows are common throughout the basin, the most significant occurrences being small gas fields in basal upper Cretaceous sandstone in the eastern part of the basin, one of which is in commercial production, and a 3 m oil column in Lindon 1 in basal Tertiary sandstone in the central basin area. A lack of commercial oil discoveries in twenty-five years of active exploration and the small size of the known gas fields, together with uncertainty about source rock quality and maturation levels, have tended to downgrade the petroleum potential of the Otway Basin. Geochemical data, mainly from the Cretaceous sequence, indicate that both Upper and Lower Cretaceous rocks have fair quality gas source potential. Some thin beds of oil-prone source rocks may be present, mainly in the Lower Cretaceous and lower Tertiary sequences. Cretaceous structural development appears to have exerted a strong control on maturation throughout the basin. Hydrocarbons formed early in the basins history are unlikely to have been preserved.

Interpretation of high-quality seismic reflection data from Bass Basin, southeastern Australia, has led to the recognition of major Early Cretaceous extensional normal faults segmented by contemporaneous transfer faults. The normal faults, which initiated development of the basin, are rotational, have low to moderate dips, and were produced by 60-80% horizontal extension (B = 1.6-2.0) of the crust beneath the basin. There are three major normal faults, with trends of 290° to 300° - one along each margin and one near the centre of the basin. The transfer fault s are vertical and trend 0200 to 030°. They are predominantly of right-lateral offset, giving rise to the northwesterly trend of the basin. The normal faults and associated tilt-block edges have had a major influence on structural evolution in the overlying hydrocarbon-prospective Eastern View Coal Measures (EVCM). A play concept is presented that relates the mid-basin tilt-block/normal fault system and associated transfer faults to structures, facies variations, and source maturity within the EVCM. A geohistory analysis of a specific location containing such a structure associated with possible direct hydrocarbon indicators shows that the lower EVCM has been oil-mature since the Oligocene, and it is suggested, therefore, that the prospectivity of the Bass Basin should be upgraded.

Sediments of the Late Palaeozoic Urana Formation in infrabasins beneath the Cainozoic Murray Basin include glaciomarine diamictite, fine-grained sediment, sandstone, and conglomerate facies. The facies assemblage is dominated by paratillites, formed by ice-rafting, and fine-grained sediments with a small ice-rafted component. Rhythmically bedded siltstone and claystone, sediment gravity-flow diamictites, traction-current deposits, and, possibly, subglacial tillites are also present. Interpretation of the facies indicates that grounded-ice deposits are absent from the glaciomarine sequence over large areas of the basin and has enabled estimation of the likely limits of grounded ice. Palaeontological and sedimentological evidence suggests that these rocks were deposited towards the end of the major Late Palaeozoic glaciation of southeastern Australia.