Geoscience Australia has recently completed a multi-year compilation of Mafic-Ultramafic Magmatic Events for the Australian continent within a GIS framework. A detailed compilation of Phanerozoic mafic-ultramafic rock units and events has been appended to the previously published maps of Archean and Proterozoic mafic-ultramafic rocks and events. The full dataset has been released as a new GIS at a nominal scale of 1:5 000 000 for users to analyse and overlay other datasets. The delineation of magmatic events in this GIS is based on several hundred published ages of mafic and ultramafic igneous rocks using different isotopic systems and minerals. The foundation for the spatial distribution of rock units in the GIS are regional solid geology compilations from the State and Northern Territory geological surveys (available mainly for the Archean and Proterozoic), and surface geology distributions elsewhere (mainly for the Phanerozoic). The solid geology extents of units provide insights into the extent of the magmatic systems under sedimentary cover. Australian mafic-ultramafic magmatic events have been defined within resolvable bands of ±10 million years. Nineteen newly-formalised Phanerozoic mafic-ultramafic magmatic events range from the ~530 Ma Truro Event, named for the Truro Volcanics in southeast Australia, to the near-continuum of mafic magmatism during the Cenozoic in eastern Australia. Together with the existing event series for the Archean and Proterozoic, the complete magmatic event record of the continent now comprises 74 defined mafic-ultramafic magmatic events. This detailed compilation in both space and time is now the most complete record of mafic-ultramafic magmatic events for any continent. The GIS data are fully attributed to their sources. However, the geological datasets from the State and Northern Territory geological surveys use non-standardised attributes for rocks or solid geology, limiting the creation of a seamless nation-wide GIS dataset of mafic and ultramafic rocks. Nevertheless, the polygon attributes will allow the integration of the Mafic-Ultramafic Magmatic Events dataset with other national-scale datasets such as the national database of whole-rock geochemistry. Users may also link the new GIS data to the original attributed polygon data in State/Northern Territory GIS sources, because original map symbols were retained. Other attributes available for analysis include (but are not limited to) the presence or absence of ultramafic components within each defined magmatic event, Stratigraphic Units Database number, basic lithology, and the crustal domain within which each event is preserved (based on the Geoscience Australia Map of Australian Crustal Elements). Relative to some other continents with comparable geology, Australia appears to be under-represented in known mafic-ultramafic intrusion-hosted nickel, PGE and chromium mineral deposits. The primary intention of the GIS of Mafic-Ultramafic Magmatic Events is the provision of information for those investigating under-explored and potentially mineralised environments in Australia that may lead to redressing the discovery imbalance. The events also provide an insight into the geodynamic development of the continent over time.

SHRIMP U-Pb zircon ages are presented for 27 samples from the Lachlan Orogen, southern Thomson Orogen and New England Orogen of New South Wales. The work was conducted under the auspices of a National Geoscience Agreement (NGA) between Geoscience Australia and the Geological Survey of New South Wales (GSNSW), to support regional mapping by GSNSW. The data reported here were collected over the period from February 2011 to June 2013.

Oil and gas discoveries in Australia's offshore basins are concentrated on the North West Shelf (Northern Carnarvon, Browse and Bonaparte basins) and Bass Strait (Gippsland, Otway and Bass basins). While discoveries have been made in a few regions outside these areas (e.g. Perth Basin), a large proportion of Australia's offshore basins remain exploration frontiers. However, the decline in oil production from the North West Shelf and Bass Strait basins since 2000 has led to an increasing exploration interest in the frontier basins. There are 35 offshore frontier basins, sub-basins and provinces located on Australia's northern, northwestern, southwestern, southern, southeastern and remote eastern continental margins, where no hydrocarbons have been discovered, but where the presence of hydrocarbon accumulations is considered possible (Figure 1). These basins are diverse in terms of geology, prospectivity and accessibility, ranging from old (e.g. Proterozoic-Paleozoic Arafura Basin) to young (e.g. Mesozoic-Cenozoic Barcoo Sub-basin), from areas widely acknowledged to be highly prospective (e.g. Ceduna Sub-basin) to those where the prospectivity is more difficult to assess (e.g. Sorell Basin), and from the nearshore (e.g. offshore Sydney Basin) to the remote (e.g. New Caledonia Basin). Geoscience Australia recently completed a report on the geology and prospectivity of frontier basins in the Australian Maritime Jurisdiction, titled 'Petroleum Geology Inventory of Australia's Offshore Frontier Basins'. This study provides a comprehensive overview of the geology, petroleum systems, exploration status and data coverage for all offshore frontier basins, sub-basins and provinces, along with an assessment of the critical science questions and exploration uncertainties for each area. This work draws on the results of Geoscience Australia's pre-competitive data programs conducted from 2003 to 2011, as well as exploration results and the geoscience literature. The study assigns a petroleum prospectivity ranking to each basin, based on the presence or absence of evidence for the existence of active petroleum systems (Table 1). The availability of data and level of knowledge in each area is reflected in a confidence rating for that ranking (Table 2). While the prospectivity of some areas is widely acknowledged to be high (e.g. Ceduna Sub-basin), the perception of prospectivity in many basins is negatively affected by the amount or quality of data available. In these basins, the acquisition of new data or targeted research could make a significant difference to the understanding of petroleum potential and likelihood of exploration success.

Aeolianite successions of low-gradient continental margins commonly show complex records of coastal dune deposition linked to a wide range of sea-level positions and climatic periods of the middle and late Pleistocene, recording both regional and broader-scale drivers of sediment production, coastal dune development and landform preservation. To better characterise the general pattern of sedimentation that occurs over Quaternary glacial-interglacial cycles on low-gradient, temperate carbonate continental shelves we examine the morphology, stratigraphy and age of aeolianite deposits in the Perth region, Western Australia. This includes an analysis of well-defined drowned coastal landforms preserved on the adjacent shelf. New and previously published optical ages provide a preliminary timeframe for the deposition of aeolianite in the Perth region and on Rottnest Island, 17 km offshore. An extensive aeolianite ridge near Perth, representing a former barrier, has Optically Stimulated Luminesence (OSL) ages that range from 120 ±12 to 103 ±10 ka (MIS 5e - 5a in the context of associated age uncertainties). OSL ages for an exposure in the same ridge 2.5 km inland, record the onlap of much older aeolianite, OSL age 415 ±70 ka, by shell-rich estuarine beds, OSL age 290 ±30 ka. A further 5.5 km inland from the coast, two thick aeolianite units, separated by a well-developed palaeosol, have stratigraphically consistent OSL ages of 310 ±30 and 155 ±20 ka. In contrast, aeolianite units that form the northern coast of Rottnest Island have OSL ages of 77 ±12 ka and 27 ±5 ka. The new OSL ages and previously reported TL and U/Th ages indicate that the bulk of the island comprises dunes deposited around the end of the Last Interglacial sensu lato (MIS 5a - 4) and during the Last Glacial (MIS 4 - 2), accumulating over a Last Interglacial coral reef and basal calcarenite. Drowned barrier and dune landforms preserved on the adjacent continental shelf reveal that barriers were formed during periods of intermediate sea level (e.g. MIS 3) and significant dune mobility occurred when the shelf was subaerially exposed. The pattern of shelf sedimentation discernible in the Perth region - large-scale coastal carbonate dune deposition during periods of high and intermediate sea level and reactivation during glacial lowstands - is largely consistent with published stratigraphic and age data for large-scale aeolianite deposits on other low-gradient carbonate shelves. Based on these data, a general model is proposed for the cycle of Quaternary sedimentation and landform evolution that occurs on these shelves, which are dynamic sedimentary environments with coastal landforms and sedimentary successions that are very sensitive to erosion and sediment reworking.

Major advances have been made in recent years in probabilistic analysis of geological hazards. Analyses of this kind are concerned with producing estimates of the probability of occurrence of a hazard at a site given the location, severity and historical occurrence of hazardous events around that site. Significant developments have been made towards the probabilistic assessment in the field of earthquake hazard leading to the development of Probabilistic Seismic Hazard Analysis (PSHA). PSHA is a widely utilised method for assessing and expressing the probability of earthquake hazard at a site of interest in terms of maximum credible intensity for return periods of interest. Probabilistic methods for assessing volcanic ash hazard at a regional scale in this way are comparatively less advanced. A methodology was developed at Geoscience Australia which modifies the four-step procedure of PSHA for volcanic ash at a regional scale, named Probabilistic Volcanic Ash Hazard Analysis (PVAHA). PVAHA considers a multitude of volcanic eruption occurrences and associated volcanic ash load attenuation relationships (developed through volcanic ash dispersal modeling) and integrates across all possible events to arrive at an annual exceedance probability for each site across a region of interest. PVAHA can be aggregated to generate geospatially-referenced maps that visually convey the expected volcanic ash hazard for sites across the region at return periods of interest, or disaggregated to determine the causal factors which dominate volcanic ash hazard at individual sites. This has important implications for identifying priority areas, from a multitude of volcanic events, for more detailed, local scale ash dispersal modeling that can be used to inform disaster risk reduction efforts. Development of the PVAHA methodology is presented here using examples from Indonesia and the benefits and limitations of the technique are discussed.

Australia's Identified Mineral Resources is an annual national assessment that takes a long-term view of Australian mineral resources likely to be available for mining. The assessment also includes evaluations of long-term trends in mineral resources, world rankings, summaries of significant exploration results and brief reviews of mining industry developments.

The petroleum exploration wells Kutjara 1 and Mulyawara 1, drilled by Rodinia Oil (Australia) Pty. Ltd in the Officer Basin in northwestern South Australia, each intersected granitic basement at depths exceeding 2400 m. Zircons from both granites were isolated for U-Pb dating via Sensitive High-Resolution Ion Micro Probe (SHRIMP), with the aim of determining magmatic crystallisation ages, and constraining the ages of any subsequent high-grade metamorphic events. The sample from the Kutjara 1 well yielded a magmatic crystallisation age of 1591 ± 11 Ma (all uncertainties quoted at 95% confidence), and the zircons feature low-Th/U rims recording subsequent high-grade metamorphism at 1167 ± 7 Ma. The adamellite from Mulyawara 1 records a magmatic crystallisation age of 1168 ± 6 Ma, and contains a small number 1615-1530 Ma inherited grains.

Gravity anomalies over granite bodies are often negative polarity and rounded polygons. These characteristics were used to trial a method to map possible locations of subsurface granite bodies. Two approaches were used to outline the geometry of rounded gravity anomalies: a) Contouring of the residual Bouguer gravity field after removal of a regional field computed by filtering of the gravity field. b) Detection of edges defined by maximum horizontal gradient of the residual Bouguer gravity field. The resulting polygons are coloured according to whether granite outcrop, or encounter in wells, falls within the gravity polygon, is near such outcrop, or not proximal to outcrop. The processing was done using software developed by the author in the Perl programming language and stored in the Energy Division software repository. The processing was organised to run in batch mode on any system on which Perl is installed, MS-Windows, Unix, Linux or NCI systems. The input and output data files are ERMapper ASCII vector format and exported to ArcGIS shape files. The visualisation tool was ER-Mapper.

This report outlines the high precision level survey completed between the SEAFRAME (Sea Level Fine Resolution Acoustic Measuring Equipment) Tide Gauge Station and continuous GNSS (Global Navigation Satellite System) station in Rarotonga, Cook Islands from 5th to 9th December2012.

This report outlines the high precision level survey completed between the SEAFRAME tide gauge and continuous GPS station in Tarawa, Kiribati from 23 - 30 April 2012.