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    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. These line dataset from the Murrindal, Vic, 1996 VIMP Survey (GSV3060) survey were acquired in 1995 by the VIC Government, and consisted of 15589 line-kilometres of data at 200m line spacing and 80m terrain clearance. To constrain long wavelengths in the data, an independent data set, the Australia-wide Airborne Geophysical Survey (AWAGS) airborne magnetic data, was used to control the base levels of the survey data. This survey data is essentially levelled to AWAGS.

  • This grid is derived from gravity observations stored in the Australian National Gravity Database (ANGD) as at February 2016 as well as data from the 2013 New South Wales Riverina gravity survey. Out of the approximately 1.8 million gravity observations 1,371,998 gravity stations in the ANGD together with 19,558 stations from the Riverina survey were used to generate this image. The grid shows isostatic residual gravity anomalies over onshore continental Australia. The data used in this grid has been acquired by the Commonwealth, State and Territory Governments, the mining and exploration industry, universities and research organisations from the 1940's to the present day. The isostatic corrections were based on the assumption that topographic loads are compensated at depth by crustal roots following the Airy-Heiskanen isostatic principle. A crustal density of 2670 kg/m3 was used for the isostatic correction, with an assumed density contrast between the crust and mantle of 400 kg/m3. An initial average depth to Moho at sea level of 37 km was used in the calculation. The isostatic corrections were then applied to the Complete Bouguer Gravity Anomaly Grid of Onshore Australia 2016 to produce the Isostatic Residual Gravity Anomaly Grid of Onshore Australia 2016.

  • This web service delivers metadata for onshore active and passive seismic surveys conducted across the Australian continent by Geoscience Australia and its collaborative partners. For active seismic this metadata includes survey header data, line location and positional information, and the energy source type and parameters used to acquire the seismic line data. For passive seismic this metadata includes information about station name and location, start and end dates, operators and instruments. The metadata are maintained in Geoscience Australia's onshore active seismic and passive seismic database, which is being added to as new surveys are undertaken. Links to datasets, reports and other publications for the seismic surveys are provided in the metadata.

  • Note on plan No. G.26-2, which shows the results of Equipotential Line surveys conducted on the Comstock Area, during the years 1937 and 1938. It is supplementary to Plan No. G.26-1 which shows the results of similar surveys on the southern part of the Mt. Lyell area. Plan No. G.26-2 should be studied together with this plan and the accompanying report dated 13th May, 1948.

  • An earlier report (Record 1950/041) has described the geophysical survey carried out early in 1950 on the Renison Bell tin field. The present report deals with the work of a second field season which commenced in November 1950 and continued until June 1951. The methods used were again the magnetic and self-potential. The 1950 survey was extended to the south and east by continuing along the Renison Bell Hill base-line a further 1000 feet south and reading stations on both sides of this base-line along traverses extending from the main quartz-porphyry dyke to the headwaters of the Montana Creek. In addition, some of the traverses were extended over the saddle between Dreadnought and Stebbins Hills as far as the Boulder tramway. The report gives an account of the survey work and its results, and provides recommendations for future testing. The geological features of the area covered by the present geophysical survey are briefly described.

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    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 Millicent, Mount Gambier - SADM Road Gravity (P195253) contains a total of 116 point data values acquired at a spacing of 750 metres. The data is located in SA and were acquired in 1952, under project No. 195253 for Department of Mines and Energy South Australia (SADME).

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    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 South Gippsland Hills Gravity (P195304) contains a total of 174 point data values acquired at a spacing between 600 and 800 metres. The data is located in VIC and were acquired in 1953, under project No. 195304 for Bureau of Mineral Resources (BMR).

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    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 Maffra-Bruthen Gravity (P195303) contains a total of 54 point data values acquired at a spacing between 600 and 800 metres. The data is located in VIC and were acquired in 1953, under project No. 195303 for Bureau of Mineral Resources (BMR).

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    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 Geraldton-Carnarvon, Canning Basin Gravity (P195307) contains a total of 1 point data values acquired at a spacing between 402 and 8045 metres. The data is located in WA and were acquired in 1953, under project No. 195307 for Bureau of Mineral Resources (BMR).

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    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 Poole Range Detail Gravity (P195310) contains a total of 32 point data values acquired at a spacing of 1500 metres. The data is located in WA and were acquired in 1953, under project No. 195310 for None.