From 1 - 10 / 1259
  • Following the proclamation of the Tatiara proclaimed region in 1984, hydrogeological investigations have been undertaken to assess the groundwater availability of the region. Groundwater supplies are obtained from an extensive unconfined aquifer. Hydrogeological conditions vary significantly through the region, with changes in aquifer lithology, depth of water table and groundwater quality. Preliminary groundwater assessments indicated that groundwater use for irrigation purposes in some areas was close to or possibly exceeded acceptable levels of groundwater extraction. Monitoring of groundwater quality has shown increased groundwater salinity in a number of observation wells, particularly in the western part of the region. It is considered that these increases are mainly due to the localised leaching of salts left in the soil profile following irrigation. An assessment of groundwater resources has been made by determining the water balance of several areas within the region, total groundwater availability being the sum of the recharge to the aquifer and the lateral groundwater inflow. In order to maintain the maximum possible groundwater throughflow in these areas, groundwater use should not exceed localised recharge.

  • 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 Geological Survey of South Australia commissioned the Gawler Craton Airborne Survey (GCAS) as part of the PACE Copper initiative. The airborne geophysical survey was flown over parts of the Gawler Craton in South Australia. The program was designed to capture new baseline geoscientific data to provide further information on the geological context and setting of the area for mineral systems (http://energymining.sa.gov.au/minerals/geoscience/pace_copper/gawler_craton_airborne_survey). This radiometric uranium image has a cell size of 0.0004 degrees (approximately 41m) and shows uranium element concentration of the Gawler Craton Airborne Survey Magnetic Radiometric and DEM Merge, SA, 2017-2019 in units of parts per million (or ppm). Noise-adjusted singular value decomposition (NASVD) has been applied to the data. NASVD is a spectral component analysis procedure for the removal of noise from gamma-ray spectra. The data used to produce this image was acquired in 2019 by the SA Government, and consisted of 1660000 line-kilometres of data at 200m line spacing and 60m terrain clearance. To constrain long wavelengths in the grid, an independent data set, the Australia-wide Airborne Geophysical Survey (AWAGS) airborne magnetic data, was used to control the base levels of the survey grid.

  • The purpose of this discussion is to relate the informal lacustrine units, A, B and C of Draper and Jensen (1976) to the broader Cainozoic stratigraphy of the area. The Cainozoic stratigraphy used follows Callen and Tedford (in press), being a slightly modified version of that shown on the published Frome 1:250 000 geological map (sheet SH54.10).

  • Lithological and palaeontological comparisons suggest correlation between the Babbagoola Beds in Western Australia and the Observatory Hill Beds of South Australia, which are considered to be the major potential source of petroleum in the eastern Officer Basin. The presence of potential petroleum traps, such as salt domes and broad anticlines, and good potential reservoir beds, such as the Lennis Sandstone and Wanna Beds in Western Australia, is now complemented by the suggestion of a potential early Cambrian petroleum source bed. Further petroleum exploration and stratigraphic drilling are warranted.

  • 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.

  • 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 Detailed Gravity Survey, SA 2006A10 (P200652) contains a total of 625 point data values acquired at a spacing between 150 and 400 metres. The data is located in SA and were acquired in 2006, under project No. 200652 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 2007 PACE Northern Olympic Domain Gravity Survey, SA (P200750) contains a total of 38881 point data values acquired at a spacing between 750 and 1500 metres. The data is located in SA and were acquired in 2007, under project No. 200750 for Primary Industries and Resources South Australia (PIRSA).

  • 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 Semi-Detailed Gravity Traverses, SA 2007A34 (P200755) contains a total of 128 point data values acquired at a spacing between 200 and 2000 metres. The data is located in SA and were acquired in 2007, under project No. 200755 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 Eucla Gawler Deep Crustal Seismic Gravity Survey (P201363) contains a total of 2086 point data values acquired at a spacing of 400 metres. The data is located in SA, WA and were acquired in 2013, under project No. 201363 for Geoscience Australia.

  • Categories  

    Gravity data measure 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. This P201750 Coompana Gravity Survey SCBA267GU 1VD is the first vertical derivative of the spheical cap Bouguer anomaly grid for the Coompana Gravity Survey (P201750). This gravity survey was acquired under the project No. 201750 for the geological survey of SA. The grid has a cell size of 0.00387 degrees (approximately 398m). A total of 13795 gravity stations at variable spacing between 500m and 2000m were acquired to produce this grid. A Fast Fourier Transform (FFT) process was applied to the original grid to calculate the first vertical derivative grid. The processed data is checked for quality by GA geophysicists to ensure that the final data released by GA are fit-for-purpose.