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  • This map is part of a series which comprises 50 maps which covers the whole of Australia at a scale of 1:1 000 000 (1cm on a map represents 10km on the ground). Each standard map covers an area of 6 degrees longitude by 4 degrees latitude or about 590 kilometres east to west and about 440 kilometres from north to south. These maps depict natural and constructed features including transport infrastructure (roads, railway airports), hydrography, contours, hypsometric and bathymetric layers, localities and some administrative boundaries, making this a useful general reference map.

  • Vertical geochemical profiling of the marine Toolebuc Formation, Eromanga Basin - implications for shale gas/oil potential The regionally extensive, marine, mid-Cretaceous (Albian) Toolebuc Formation, Eromanga Basin hosts one of Australia's most prolific potential source rocks. However, its general low thermal maturity precludes pervasive petroleum generation, although regions of high heat flow and/or deeper burial may make it attractive for unconventional (shale gas and shale oil) hydrocarbon exploration. Previous studies have provided a good understanding of the geographic distribution of the marine organic matter in the Toolebuc Formation where total organic carbon (TOC) contents range to over 20% with approx. half being of labile carbon and convertible to gas and oil. This study focuses on the vertical profiling, at the decimetre to metre scale, of the organic and inorganic geochemical fingerprints within the Toolebuc Formation with a view to quantify fluctuations in the depositional environment and mode of preservation of the organic matter and how these factors influence hydrocarbon generation thresholds. The Toolebuc Formation from three wells, Julia Creek-2 and Wallimbulla-2 and -3, was sampled over an interval from 172 to 360m depth. The total core length was 27m from which 60 samples were selected. Cores from the underlying Wallumbilla Formation (11 samples over 13m) and the overlying Allaru Mudstone (3 samples) completed the sample set. Bulk geochemical analyses included %TOC, %carbonate, %total S, -15N kerogen, -13C kerogen, -13C carbonate, -18O carbonate, and major, minor and tracer elements and quantitative mineralogy. More detailed organic geochemical analyses involved molecular fossils (saturated and aromatic hydrocarbons, and metalloporphyrins), compound specific carbon isotopes of n-alkanes, pyrolysis-gas chromatography and compositional kinetics. etc.

  • Despite the extensive resources, ongoing mining activity and economic importance of iron-ore in Australia, the genesis of iron-ore and particularly its timing, remains relatively poorly understood. Most iron-ore in Australia is interpreted to originate as Banded Iron Formation (BIF) that has subsequently experienced one or more fluid leaching events in which silica is removed, leaving the residual rock highly enriched in iron (Morris and Kneeshaw, 2011). While this general model appears relatively well established, questions remain regarding whether iron-enrichment typically occurs over one or more events, the timing of such events, and the controls on fluid movement leading to iron enrichment. Here we report textural observations and U-Pb isotopic results from zircon extracted from hematite ore from the Iron Knob mine in the Middleback Range, South Australia. The U-Pb ages have yielded unexpected results that are interpreted to indicate at least some fluid interaction and iron enrichment in the Middleback Range occurred in multiple stages through the Paleozoic and Mesozoic. Such timing is unexpected given the local geological context, but may in part be explained by early Paleozoic tectonic events in the Adelaide Fold Belt (Delamerian Orogeny), ~100 km to the east, having played a role in mobilising supergene fluids within the adjacent margin of the Gawler Craton.

  • Water resource assessment for the Great Artesian Basin. Synthesis of a report to the Australian Government from the CSIRO Great Artesian Basin Water Resource Assessment

  • Stations on the Australian continent receive a rich mixture of ambient seismic noise from the surrounding oceans and the numerous small earthquakes in the earthquake belts to the north in Indonesia, and east in Tonga-Kermadec, as well as more distant source zones. The noise field at a seismic station contains information about the structure in the vicinity of the site, and this can be exploited by applying an autocorrelation procedure to the continuous records. By creating stacked autocorrelograms of the ground motion at a single station, information on crust properties can be extracted in the form of a signal that includes the crustal reflection response convolved with the autocorrelation of the combined effect of source excitation and the instrument response. After applying suitable high pass filtering the reflection component can be extracted to reveal the most prominent reflectors in the lower crust, which often correspond to the reflection at the Moho. Because the reflection signal is stacked from arrivals from a wide range of slownesses, the reflection response is somewhat diffuse, but still sufficient to provide useful constraints on the local crust beneath a seismic station. Continuous vertical component records from 223 stations (permanent and temporary) across the continent have been processed using autocorrelograms of running windows 6 hours long with subsequent stacking. A distinctive pulse with a time offset between 8 and 30 s from zero is found in the autocorrelation results, with frequency content between 1.5 and 4 Hz suggesting P-wave multiples trapped in the crust. Synthetic modelling, with control of multiple phases, shows that a local Ppmp phase can be recovered with the autocorrelation approach. This approach can be used for crustal property extraction using just vertical component records, and effective results can be obtained with temporary deployments of just a few months.

  • Geoscience Australia and CO2CRC have constructed a greenhouse gas controlled release facility to simulate surface emissions of CO2 (and other greenhouse gases) from the soil into the atmosphere under controlled conditions. The facility is located at an experimental agricultural station maintained by CSIRO Plant Industry at Ginninderra, Canberra. The design of the facility is modelled on the ZERT controlled release facility in Montana. The facility is equipped with a 2.5 tonne liquid CO2 storage vessel, vaporiser and mass flow controller unit with a capacity for 6 individual metered CO2 gas streams (up to 600 kg/d capacity in total). Injection of CO2 into the soil is via a 120m long slotted HDPE pipe installed horizontally 2m underground. This is equipped with a packer system to partition the well into six CO2 injection chambers. The site is characterised by the presence of deep red and yellow podsolic soils with the subsoil containing mainly kaolinite and subdominant illite. Injection is above the water table. The choice of well orientation based upon the effects of various factors such as topography, wind direction, soil properties and ground water depth will be discussed. An above ground release experiment was conducted from July - October 2010 leading to the development of an atmospheric tomography technique for quantifying and locating CO2 emissions1. An overview of monitoring experiments conducted during the first subsurface release (January-March 2012), including application of the atmospheric tomography technique, soil flux surveys, microbiological surveys, and tracer studies, will be presented. Additional CO2 release experiments are planned for late 2012 and 2013. Poster presented at 11th Annual Conference on Carbon Capture Utilization & Sequestration, April 30 - May 3, 2012, Pittsburgh, Pennsylvania

  • The southwest margin is a complex and relatively poorly studied part of Australia's offshore continental region and includes the Southern Carnarvon, Perth and Mentelle basins, as well as the Naturaliste and Wallaby plateaus. A series of seismic profiles are interpreted, in conjunction with potential field data, to reassess the nature of the continent-ocean boundary (COB) across the region. Results highlight how the structural architecture of the margin varies significantly along strike according to the following criteria: a) the relative orientation of the margin with respect to the initial extension direction, b) the nature and extent of break-up related magmatism and c) the nature and width of the continent-ocean transition zone. Margin segmentation is directly linked to the location of major oceanic fracture zones as well as to the location and geometry of the major Palaeozoic to Mesozoic basins. Furthermore, the correlation between margin segmentation and structural trends of underlying Proterozoic Pinjarra Orogen suggests some basement control on margin evolution. The revised COB interpretation is combined with recent Indian Ocean plate reconstructions incorporating potential field data from the abyssal plains of west Australia and east Antarctica, including the Early Cretaceous southwest Australian margin. Comparisons between this model and recent basin scale sequence stratigraphic studies across the region provide new insights into Mesozoic basin evolution, including the relative timing of break-up within each basin. In addition, the model illustrates the possible impacts of Valanginian to Aptian transform margin development on the tectonic and thermal evolution of the northern Perth Basin depocentres.

  • After CO2 is injected into the saline aquifer, the formation water inside the porous media becomes more acidic. This will significantly affect the original chemical equilibrium underground, and induce or speed up various processes of dissolution and precipitation depending on the reservoir pressure, temperature and salinity of formation water. The Early Cretaceous Gage Sandstone has been identified as a potential reservoir unit suitable for large-scale CO2 storage in the offshore southern Perth Basin. This study assesses the contribution of mineralisation trapping to CO2 storage capacity of the Gage Sandstone through a comprehensive geochemical modelling.

  • In ecology, a common form of statistical analysis relates a biological variable to variables that delineate the physical environment, typically by fitting a regression model or one of its extensions. Unfortunately, the biological data and the physical data are frequently obtained from eparate sources of data. In such cases there is no guarantee that the biological and physical data are co-located and the regression model cannot be used. A common and pragmatic solution is to predict the physical variables at the locations of the biological variables and then to use the predictions as if they were observations.We show that this procedure can cause potentially misleading inferences and we use generalized linear models as an example. We propose a Berkson error model which overcomes the limitations. The differences between using predicted covariates and the Berkson error model are illustrated by using data from the marine environment, and a simulation study based on these data.