Geoscience Australia (GA), as custodian of the geographical and geological data and knowledge of the nation, has recently implemented a new data discovery and delivery system for offshore wells and surveys the National Offshore Petroleum Information Management system (NOPIMS). In order to encourage adoption and use of the NOPIMS by industry, this five page article for PESA News describes the origins of the NOPIMS, its current state and future development plans.

Nara Inlet in the Whitsunday Islands is a natural depocenter for clastic and carbonate sediment on the middle shelf of the central Great Barrier Reef (GBR) platform. Three sediment cores were collected from the inlet to understand sediment accumulation in this tropical mixed clastic/carbonate system over time. Surface and subsurface sediment is comprised of two main components: terrigenous clay and shallow marine carbonate. Similar to other regions on the middle shelf of the GBR platform, the carbonate component, 25.80% by weight and dominated by Sr-poor foraminifera tests and mollusc shells, generally increases towards the surface. Radiocarbon ages derived from tests of benthic foraminifera indicate that the top 3 m of sediment accumulated within the last 3000 years, but that the rate has slowed toward present-day. The change in clastic and carbonate abundance therefore indicates a system where both clastic and carbonate accumulation has decreased over time, but where clastic accumulation has decreased faster. Reduced clastic accumulation may reflect progressive impedance of terrigenous input by a laterally growing fringing reef at the mouth of Nara Inlet. Likewise, reduced carbonate accumulation may reflect preferential reef growth and carbonate deposition outside of the inlet. Even though clastic accumulation has decreased significantly over time, the late Holocene mass, composition, and distribution of clastic material in Nara Inlet implies a terrigenous source previously unrecognized in models for the evolution of the GBR platform. Large amounts of terrigenous sediment probably were stored around topographic highs on the middle shelf during lowstand and early transgression. This clastic material was then removed over time, mixed with autochthonous carbonate, and deposited in embayments on the middle shelf. The accumulation of sediment on the middle shelf of a tropical mixed clastic/carbonate margin is not straightforward.

Palaeomagnetic, rockmagnetic and magnetic fabric results are presented for a Carboniferous (Visean to Westphalian) succession of felsic, mainly ignimbritic, volcanic and volcaniclastic rocks from the Rocky Creek Block of the northern Tamworth Belt, southern New England Orogen. Detailed thermal demagnetization of 734 samples from 64 sites has shown three groups of magnetic components with low (LT: up to 300 degrees C), intermediate (IT: 300 to 600 degrees C) and high (HT: mainly 500 to 680 degrees C) unblocking temperature ranges. Analysis and interpretation of component directions have established well-defined primary magnetization results fro 29 sites and evidence for four magnetic overprint phases.The overprints are of widespread (a,c) or localized (b,d) occurrence and are attributed to: a mid_tertiary weathering event (a: mainly LT); or to fluid movements (b,c,d) associated with either Late Cretaceous opening of the Tasman Sea (b: mainly HT); or to thrusting during the Middle Triassic main phase of the Hunter_Bowen Orogeny (c: mainly IT); or to latest Carboniferous - Early Permian formation of the Bowen-Gunnedah-Sydney Basin system (d: IT,HT). Rockmagnetic (Lowrie-Fuller test, IRM acquisition, Lowrie-test, low- and high-temperature susceptibility cycling) and palaeomagnetic analyses indicate predominance of magnetite carriers with main unblocking temperatures ranging from 400 to between 500 and 580 degrees C, and less prevalent presence of hematite carriers with unblocking temperature ranges generally up to 640 degrees C and for some sites up to 680 degrees C. Multidomain (MD-) magnetite is prevalent in the volcaniclastic rocks. Most of the volcanic rocks with well-defined primary magnetization components show evidence for single domain (SD-) magnetite with no, or only limited, presence of MD-magnetite. See paper for remainder of abstract

We propose a geodynamic model for the generation of Fe oxide Cu-Au deposits in the eastern Gawler Craton. Rifting during the early Calymnian Period, at 1.59 Ga, produced steep geothermal gradients, active magmatism, regional-scale faulting, and immature clastic sedimentation. Major NNW?SSE-trending, dextral transtensional faults exerted fundamental structural controls on several elements of the mineral system: the geometry of intrusion of magmas of the Hiltaba Suite; the provision of fluid pathways for magnetite- and haematite-buffered fluids; creation of basinal space for the effusive lavas of the Gawler Range Volcanics and the overlying terrigeneous sediments of the Pandurra Group; and propagation of near-surface fault tips giving rise to fault-bound hydrothermal breccias. We demonstrate that faults active at 1.59 Ga were of sufficient dimension and seismic longevity to have acted as fluid pumps within the mineral system. Their size and location imply multiple sources for metals in the Olympic Dam deposit and other Fe oxide Cu-Au occurrences in the region. Multiple sources would have resulted in some of the anomalous features of the mineralisation, such as non-magmatic Br:Cl ratios, and magmatic and juvenile, mafic isotopic signatures, all noted by previous workers. Isostatic footwall uplift in the actively extending system may have compressed the regional geothermal gradients, and brought rock volumes altered by hot, reduced fluids into contact with circulating cooler, oxidised fluids. In general, fluid circulation and deposition was enhanced by deformation-induced permeabilities and hydrofracture. In the time-span of the mineral system, say 3 million years, mineralisation cycles (source-transport-deposition) may have repeated 102 to 106 times, depending on the hydraulic conductivity of the source rocks. Some associations at the Olympic Dam deposit, such as granite and maar-like volcanism, are fortuitous and are not essential elements of the mineral system. In the light of the geodynamic model, geophysical. geochemical, and petrological data may be examined for evidence of likely source rocks, fluid pathways, and suitably oxidised magnetite deposits that may contain ore.

The distribution of volcanic-hosted massive sulphide deposits through time is episodic, involving relatively short time intervals of apparent high productivity and long intervals of low productivity. This distribution is principally related to the geodynamic evolution of the Earth. The vast majority of these deposits is associated with the assembly of supercontinents and form along convergent margins, generally in back-arc basins or rifted arcs. This contrasts with the distribution of black smoker deposits, which presently form along both convergent margins, particularly in the western Pacific, and divergent margins at mid-ocean ridges. However, the latter environment is rarely preserved deep into the geological past. There also appear to be systematic patterns in a number of other features of volcanic-hosted massive deposits through time. Deposits hosted by mafic-dominated successions are dominant in Archean to Proterozoic rocks, whereas deposits hosted by felsic-dominated successions are most common in Phanerozoic rocks. Geochemical characteristics of felsic rocks within the host successions and ore lead and sulphur isotope data of the ores have also changed with time. This suggests changes in the process of subduction and/or changes in the characteristics of the over-riding plate with time, consistent with isotopic and geologic evidence for greater reworking of pre-existing crust during the Phanerozoic. Other secular changes that are reflected in characteristics of volcanic-hosted massive sulphide deposits include the redox state and salinity of coeval oceans. As an example, both the abundance of sulphate minerals and sulphur isotope patterns reflect the development of periods of anoxic conditions over time, with major intervals of anoxia, reflected by a virtual lack or low abundance of sulphate minerals in volcanic-hosted massive sulphide deposits in the Mesoarchean to the Paleoproterozoic, and shorter intervals since.

The Browse Basin located offshore on Australia's North West Shelf hosts considerable, but as yet undeveloped, petroleum resources with 36 Tcf EUR (Estimated Ultimate Recovery) of gas and 1148 MMbbl of condensate. It is poised to become Australia's next major conventional liquefied natural gas (LNG) province with the Ichthys, Prelude and Concerto fields expected to be in production by the end of 2016. Significant gas accumulations are also found along, and to the northeast of, the Brecknock-Scott Reef Trend (Calliance, Brecknock, Torosa and Poseidon) and in the Heywood Graben (Crux). Despite the economic importance of these fields and the extensive ongoing exploration activity, the origin of hydrocarbons remains ambiguous and a thorough geochemical evaluation of reservoir fluids and source rocks was carried out to redefine the petroleum systems of the Browse Basin. Geochemical data reveal that the gas-prone source rocks occurring throughout the Lower to Middle Jurassic Plover Formation have pervasively charged reservoirs of the Browse Basin at numerous stratigraphic levels. On the other hand, oil-prone source rocks within the Upper Jurassic lower Vulcan and Lower Cretaceous Echuca Shoals formations appear to be charge limited. The fluvio-deltaic sediments of the Plover Formation are the primary source for the dry gas found in the Plover reservoirs of the Brecknock-Scott Reef Trend and Ichthys fields. The Plover source rocks have also contributed to the wet gas accumulations reservoired within the Upper Jurassic Brewster Member of the Ichthys and Prelude/Concerto fields with additional inputs from the lower Vulcan Formation. Gases from the Crux field in the Heywood Graben are isotopically more enriched in 13C than any gases generated from the Caswell Sub-basin depocentre suggesting derivation from coal-rich facies within thick Jurassic syn-rift sediments. The few sub-economic oil discoveries made in the Browse Basin are confined to the central Caswell Sub-basin (Caswell) and to the Yampi Shelf (Cornea, Gwydion and surrounds) where oil, together with some gas, is found in Cretaceous reservoirs. Molecular and carbon isotopic data show that the oil, and the gas to some extent, is derived from marine organic matter within the Echuca Shoals Formation. However, accumulations on the Yampi Shelf also contain gases sourced from Plover source rocks, emphasising the migration of multiple hydrocarbon charges towards the basin margins.

The Cooper Basin is a Late Carboniferous-Middle Triassic intracratonic basin in north-eastern South Australia and south-western Queensland. The basin is Australia's premier onshore hydrocarbon producing province and is nationally significant, providing domestic gas for the East Coast Gas Market. Exploration activity in region is experiencing a revival with numerous explorers pursuing newly identified unconventional hydrocarbon plays, however the undiscovered unconventional gas resources in the basin remains poorly defined. This study reviews the hydrocarbon prospectivity of the Cooper Basin, with a focus on unconventional gas resources. Regional basin architecture is characterised through compilation and integration of formation tops, structure surfaces and isopach maps, indicating that the wider extent of the Toolachee and Patchawarra formations may extend further north in Queensland than previously mapped. Source distribution and quality are reviewed demonstrating the abundance of source material across the whole basin. The Toolachee and Patchawarra formations are the richest source units, however organic rich rocks areTOC is also present in the Nappamerri, Daralingie and Epsilon formations, and the Roseneath and Murteree shales. Petroleum systems modelling, incorporating new compositional kinetics, source quality and TOC maps, highlights the variability in burial, and thermal and hydrocarbon generation histories between depocentres. Although initial hydrocarbon generation occurred in the Permian, peak oil and gas expulsion across the basin occurred in the Cretaceous. Pressure distribution estimates are made for all major depocentres to better characterise variation in overpressure distribution. The Cooper Basin hosts a range of unconventional gas plays types, including the very extensive basin-centred gas play and tight gas accumulations in the Gidgealpa Group, deep coal seam gas associated with the Patchawarra and Toolachee formations, as well as the less-extensive shale gas plays in the Murteree and Roseneath sShales. However the overlapping nature of these plays makes it more convenient to consider them within the context of a single combined Gidgealpa Group unconventional gas play. The possible extent of the combined Gidgealpa Group gas play fairway is defined using a common risk segment mapping workflow. Low and high confidence play fairway extents are also calculated. In South Australia and the western most areas of Queensland, the combined gas play fairway maps show that the Nappamerri and Allunga troughs are highly prospective, along with the deepest areas of the Patchawarra and Arrabury troughs. The play fairway maps also shows prospectivity potential for unconventional gas further northeast in Queensland, including areas of the Windorah Tough and Ullenbury Depression, although reservoir thickness and maturity are the key risks for this play type outside the central depocentres and overpressure remains less well constrained due to lack of data. The prospectivity of the Cooper Basin for unconventional hybrid plays for gas far exceeds its currently known conventional resources by at least an order of magnitude. Whilst significant additional work is required to better characterise key petroleum systems elements, the play fairway area estimated for the combined Gidgealpa Group gas play is significantly larger than that of the Roseneath and Murteree shale gas plays alone, suggesting very large volumes of gas in place and highlighting the Cooper Basin's significance as a world class unconventional gas province.

A multi-disciplinary systems mapping approach, utilising airborne electromagnetics (AEM), and validated by a 7.5 km drilling program (100 sonic and rotary mud holes), and complementary hydrogeological and hydrogeochemical investigations, has identified potential groundwater resources stored within Pliocene aquifers (Calivil Formation (CFm) and Loxton Parilla Sands (LPS)) to depths of ~100m beneath the Darling River floodplain. The Pliocene aquifers are sandwiched between thick clay aquitards, and vary from confined to 'leaky confined' systems. The CFm, which extends over the north and central parts of the study area, varies significantly in thickness (0-70 m). This variability results from (1) in-filling of broad (structurally-controlled) palaeovalleys in an undulating palaeo-landscape, with relief of up to 40m from valley bottoms to hill tops; and (2) post-depositional tectonic effects that include structural inversion on faults, as well as warping and tilting. The lower bounding surface of the CFm is marked by an erosional contact (10 m year hiatus) with Renmark Group sediments. Facies analysis indicates that the CFm was deposited in deep braided streams across a dissected sedimentary landscape. Overall, the sequence is fining-upwards, with evidence for transgression over the LPS. Channel fill materials comprise gravels and sands, and local fine-grained units represent abandoned channels and local floodplain sediments. The upper surface of the CFm is irregular, with up to 16 m of relief evident, due to a combination of tectonics and depositional filling of channel and bar topography in the upper CFm. Integration of textural and hydraulic testing data has revealed there are five hydraulic classes within the CFm, ranging from clays to gravels. At a regional scale (kms), sands and gravels are widely distributed with particularly good aquifers developed in palaeochannels and at the confluence of palaeo-river systems. In these strategic locations, the CFm has high storage capacity, very high transmissivities (up to 50 l/s), and significant volumes of fresh groundwater. At a local scale, there is considerable lithological heterogeneity (10s to 100s of metres) within the palaeochannels. The use of AEM was critical to the targeting of premium aquifer sites and detailed hydrogeological investigations.

The Broken Hill Managed Aquifer Recharge (BHMAR) project was tasked with identifying and assessing MAR and/or groundwater extraction options to enhance Broken Hill's water security. Investigations have identified a priority site (Jimargil) near the Menindee Lakes Storages (MLS). The identified options at this site take a conjunctive approach by combining the continued use of river/lake water when surface water is abundant, with groundwater extraction during drought conditions. The options at Jimargil include Aquifer Storage and Recovery (ASR) as well as direct groundwater extraction. All options utilise the Calivil Formation aquifer. Risk assessments using national MAR and drinking water quality (ADWG) guidelines have found that ASR would provide significant long-term drought security, with high recovery efficiencies (>90%) predicted. The main risks associated with ASR are biological, physical and chemical clogging related to the mixing of oxygenated river source water with more reduced ambient groundwater. More specifically, the main water quality maximal risks to human health and environment are: - Pathogens (e.g. Cryptosporidium, Giardia and bacteria) - Inorganic chemicals (particularly arsenic and iron) - Salinity and sodicity - Nutrients (e.g. ammonia) - Organic chemicals (e.g. cyanobacterial toxins) - Turbidity and particulates (affecting disinfection and also potentially causing biological and physical clogging of the ASR well). While ASR at this site has a moderate to high technical risk due to the pioneering nature of the project, residual risks have been assessed as low for human health and the environment if the supplementary water treatment trains are included. Groundwater extraction would deliver a measure of drought security, and may have lower capital and initial treatment costs than ASR. However, numerical groundwater modelling is required to determine the duration and rates of supply possible from this site, including the potential for salinisation and exceedances with respect to ADWG thresholds, and to assess potential environmental impacts from prolonged extraction during periods of negligible recharge. Overall, conjunctive management of surface water and groundwater involving ASR options at the Jimargil site would provide the greatest drought security for Broken Hill.

Surface-groundwater interactions are often poorly understood. This is particularly true of many floodplain landscapes in Australia, where there is limited mapping of recharge and discharge zones along the major river systems, and only generalised quantification of hydrological fluxes based on widely spaced surface gauging stations. This is compounded by a lack of temporal data, with poor understanding of how surface-groundwater interactions change under different rainfall, river flow and flood regimes. In this study, high resolution LiDAR, in-river sonar, and airborne electromagnetic (AEM) datasets (validated by drilling) have been integrated to produce detailed 3-dimensional mapping that combines surface geomorphology and hydrogeology. This mapping enables potential recharge zones in the river and adjacent landscape to be identified and assessed under different flow regimes. These potential recharge zones and groundwater flow pathways were then compared against the spatial distribution of discontinuities in near-surface and deeper aquitard layers derived from the AEM interpretation. These 3D mapping constructs provide a framework for considering groundwater processes. Hydrochemistry data, allied with hydraulic data from a bore monitoring network, demonstrate the importance of recharge during significant flood events. In many places, the AEM data also affirm the spatial association between fresher groundwater resources and sites of river and floodplain leakage. At a more localised scale, hydrogeochemical data allows discrimination of lateral and vertical fluxes. Overall, this integrated approach provides an important conceptual framework to constrain hydrogeological modelling, and assessments of sustainable yield. The constructs are also invaluable in targeting and assessing managed aquifer recharge (MAR) options.