From 1 - 10 / 1120
  • Categories  

    Gravity data measures small changes in gravity due to changes in the density of rocks beneath the Earth's surface. The data collected are processed via standard methods to ensure the response recorded is that due only to the rocks in the ground. The results produce datasets that can be interpreted to reveal the geological structure of the sub-surface. The processed data is checked for quality by GA geophysicists to ensure that the final data released by GA are fit-for-purpose. This Seismic Gravity Trav Central Eromanga Basin Trav 12 (P198119) contains a total of 48 point data values acquired at a spacing of 650 metres. The data is located in QLD and were acquired in 1981, under project No. 198119 for None.

  • Categories  

    Gravity data measures small changes in gravity due to changes in the density of rocks beneath the Earth's surface. The data collected are processed via standard methods to ensure the response recorded is that due only to the rocks in the ground. The results produce datasets that can be interpreted to reveal the geological structure of the sub-surface. The processed data is checked for quality by GA geophysicists to ensure that the final data released by GA are fit-for-purpose. This NSW, QLD Absolute AFGN Survey (P201690) contains a total of 5 point data values acquired at a spacing of 750 metres. The data is located in NSW, QLD and were acquired in 2016, under project No. 201690 for Geoscience Australia.

  • Twenty-seven whole rock samples and eleven extracted samples or kerogen concentrates from five potential Permian sources within the Cooper Basin, Australia were provided for petroleum generation characterisation (eleven samples) and PhaseKinetic characterisation (six samples) following the approach of di Primio and Horsfield (2006). Organofacies Type definition was performed for twentyseven samples and characterisation of free hydrocarbons for 15 samples. The evolution of late gas potentials as a function of organofacies and maturity were determined for fifteen samples following the approach of Mahlstedt (2012), as well as kinetic parameters of primary and secondary gas formation (one sample) using a modified GORFit - model (Mahlstedt et al., 2013). Thermal maturity of Patchawarra Fm. samples is broad (0.5 5.5% VR) offering an insight into differences of gas potential.

  • The Southern Thomson Orogen VTEMplus® AEM survey was undertaken as part of Geoscience Australia's contribution to the Australian Academy of Science's UNCOVER initiative, which has been adopted as part of the Australia Government's National Mineral Exploration Strategy. The aim of the survey was to demonstrate the application of AEM as an exploration tool under cover by generating new data and information regarding depth to basement and cover character. This information is provided to mineral explorers to assist reducing exploration risk by better targeting of drilling in the greenfields southern Thomson Orogen region. This report provides a background to the survey, including reviews of the basement and cover geology and mineral systems potential of the southern Thomson Orogen. We present the specifications of the airborne survey, and detail the innovative processing and inversion techniques that have been developed and applied to the AEM data. These inversion innovations have enabled the generation of higher precision information from the AEM data, resulting in higher confidence in geological and geophysical interpretations of the basement-cover interface and overlying basin stratigraphy. Data interpretation methods are presented, followed by a series of case studies demonstrating the effectiveness of the technique for identifying and mapping resistive basement, for characterising cover sequences, for mapping weathering products and for mapping post-depositional structures. The process and results of basement-cover interface mapping are presented along with conductivity characterisation and recognition of key stratigraphic (and hydrostratigraphic) units within the Eromanga and Lake Eyre basin cover sequences. Interpretation of a potential mineral system in resistive basement is discussed, and the utility of the technique for assessing the distribution and depth of weathering in basement rocks, along with interpretation of tectonic features, are also assessed. The application of AEM as a basement and cover mapping tool are clearly demonstrated and the potential utility of such techniques for reducing exploration risk in greenfields regions is clear. In the southern Thomson Orogen interpreted AEM data has the potential to assist in targeting exploration and drilling for shallowly-buried basement-hosted mineral systems to 150-200 m and in exploring for distal footprints within the overlying basin cover sequences.

  • This report presents an overview of basin architecture, tectonic evolution and lithostratigraphy and is the first part of a series of reports reviewing various aspects of the petroleum prospectivity of the Cooper Basin. Structural architecture, formation extent and thickness is characterised through construction of a regional 3D geological model, designed to capture the formations associated with the major play types in the basin. Existing published Cooper Basin horizons are integrated with formation tops and new seismic data interpretations, ensuring seamless integration of datasets across the state border. The late Neoproterozoic to Cenozoic evolution of the Cooper Basin region is discussed in the context of the broader tectonic evolution of eastern Australia. In addition, stratigraphy ages have been updated to produce a revised Cooper Basin stratigraphic chart, consistent with the 2012 Geological Time Scale and updated spore pollen age calibration. The new formation ages, along with the timing of key tectonic events and regional erosion estimates, are assigned to the 3D geological model, enabling extraction of time-slice cross-sections through the basin, capturing the regional burial history of the Cooper-Eromanga-Lake Eyre succession Isopachs extracted from the 3D model are used to review the extent and thickness of each formation. The Permian Toolachee and Patchawarra formations in Queensland are shown to have a wider extent compared with previous studies. In addition, the boundaries of Roseneath and Murteree shales were revised, although their distribution still remains uncertain in areas such as the Arrabury Depression. Lithofacies analysis published for South Australia are integrated with new electrofacies mapping results in Queensland to produce the first basin wide set of lithofacies maps for the Toolachee, Daralingie, Epsilon and Patchawarra formations. The resulting net sand, silt, shale and coal thickness maps characterise the regional distribution of key source, reservoir and seal intervals across the basin. Maps of net coal and shale thickness clearly demonstrate an abundance of potential source rock facies in the Toolachee and Patchawarra formations in all regions. Additional potential source rock facies can be found in the Roseneath and Murteree shales and coals and shales of the Daralingie and Epsilon formations. Net sand thickness maps highlight possible reservoir facies distribution. This study presents the most detailed regional 3D geological model published for the Cooper Basin to date. The model is designed to characterise the formations associated with the basin's key petroleum systems elements, providing a framework for future regional scale petroleum systems analysis and resource assessment studies. While this work provides important insights into both the conventional and unconventional hydrocarbon prospectivity of the basin, it also has application for the assessment of other resources such as groundwater.

  • Categories  

    Digital Elevation data record the terrain height variations from the processed point- or line-located data recorded during a geophysical survey. This GSQ Southern Bowen Basin Qld elevation grid geodetic is elevation data for the Southern Bowen Basin, Qld, 2004. This survey was acquired under the project No. 1072 for the geological survey of QLD. The grid has a cell size of 0.001 degrees (approximately 106m). This grid contains the ground elevation relative to the geoid for the Southern Bowen Basin, Qld, 2004. It represents the vertical distance from a location on the Earth's surface to the geoid. The data are given in units of meters. The processed data is checked for quality by GA geophysicists to ensure that the final data released by GA are fit-for-purpose.

  • Categories  

    The radiometric, or gamma-ray spectrometric method, measures the natural variations in the gamma-rays detected near the Earth's surface as the result of the natural radioactive decay of potassium (K), uranium (U) and thorium (Th). The data collected are processed via standard methods to ensure the response recorded is that due only to the rocks in the ground. The results produce datasets that can be interpreted to reveal the geological structure of the sub-surface. The processed data is checked for quality by GA geophysicists to ensure that the final data released by GA are fit-for-purpose. The terrestrial dose rate grid is derived as a linear combination of the filtered K, U and Th grids. A low pass filter is applied to this grid to generate the filtered terrestrial dose rate grid. This GSQ Southern Bowen Basin Qld dose rate grid geodetic has a cell size of 0.001 degrees (approximately 106m) and shows the terrestrial dose rate of the Southern Bowen Basin, Qld, 2004. The data used to produce this grid was acquired in 2004 by the QLD Government, and consisted of 74554 line-kilometres of data at 400m line spacing and 80m terrain clearance.

  • Categories  

    The radiometric, or gamma-ray spectrometric method, measures the natural variations in the gamma-rays detected near the Earth's surface as the result of the natural radioactive decay of potassium (K), uranium (U) and thorium (Th). The data collected are processed via standard methods to ensure the response recorded is that due only to the rocks in the ground. The results produce datasets that can be interpreted to reveal the geological structure of the sub-surface. The processed data is checked for quality by GA geophysicists to ensure that the final data released by GA are fit-for-purpose. This radiometric thorium grid has a cell size of 0.001 degrees (approximately 106m) and shows thorium element concentration of the Southern Bowen Basin, Qld, 2004 in units of parts per million (or ppm). The data used to produce this grid was acquired in 2004 by the QLD Government, and consisted of 74554 line-kilometres of data at 400m line spacing and 80m terrain clearance.

  • Categories  

    The radiometric, or gamma-ray spectrometric method, measures the natural variations in the gamma-rays detected near the Earth's surface as the result of the natural radioactive decay of potassium (K), uranium (U) and thorium (Th). The data collected are processed via standard methods to ensure the response recorded is that due only to the rocks in the ground. The results produce datasets that can be interpreted to reveal the geological structure of the sub-surface. The processed data is checked for quality by GA geophysicists to ensure that the final data released by GA are fit-for-purpose. This radiometric potassium grid has a cell size of 0.001 degrees (approximately 106m) and shows potassium element concentration of the Southern Bowen Basin, Qld, 2004 in units of percent (or %). The data used to produce this grid was acquired in 2004 by the QLD Government, and consisted of 74554 line-kilometres of data at 400m line spacing and 80m terrain clearance.

  • Categories  

    Total magnetic intensity (TMI) data measures variations in the intensity of the Earth's magnetic field caused by the contrasting content of rock-forming minerals in the Earth crust. Magnetic anomalies can be either positive (field stronger than normal) or negative (field weaker) depending on the susceptibility of the rock. The data are processed via standard methods to ensure the response recorded is that due only to the rocks in the ground. The results produce datasets that can be interpreted to reveal the geological structure of the sub-surface. The processed data is checked for quality by GA geophysicists to ensure that the final data released by GA are fit-for-purpose. This GSQ Southern Bowen Basin Qld magnetic vd1 grid geodetic is a first vertical derivative of the Total Magnetic Intensity grid for the Southern Bowen Basin, Qld, 2004. This grid has a cell size of 0.001 degrees (approximately 106m). The grid has units of nanoTesla per km (or nT/km). The data used to produce the TMI grid was acquired in 2004 by the QLD Government, and consisted of 74554 line-kilometres of data at 400m line spacing and 80m terrain clearance. A Fast Fourier Transform (FFT) process was applied to the original grid to calculate the first vertical derivative grid.