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 rtp vd1 grid geodetic is the first vertical derivative of the TMI RTP grid of the Southern Bowen Basin, Qld, 2004 survey. This grid has a cell size of 0.001 degrees (approximately 106m) , and given in units of nT per metre (nT/m). 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. The data has had a variable reduction to the pole applied to centre the magnetic anomaly over the magnetised body. The VRTP processing followed a differential reduction to pole calculation up to 5th order polynomial. Magnetic inclination and declination were derived from the IGRF-11 geomagnetic reference model using a data representative date and elevation representative of the survey. A first vertical derivative was calculated by applying a fast Fourier transform (FFT) process to the TMI RTP grid of the Southern Bowen Basin, Qld, 2004 survey to produce this grid. This grid was calculated using an algorithm from the INTREPID Geophysics software package. This grid shows the magnetic response of subsurface features with contrasting magnetic susceptibilities. The grid can also be used to locate structural features such as dykes.

This GSV Greens Creek Vic pot tho ura totg 4band radiometric grid geodetic is an airborne-derived radiometric Potassium, Thorium and Uranium data over a sun shaded total count radiometric data for the Greens Creek, Vic, 1988 (GSV1670). 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 uranium (K), uranium (U) and uranium (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 GSV Greens Creek Vic pot tho ura totg 4band radiometric grid geodetic has a cell size of 0.0005 degrees (approximately 50m). The data used to produce this grid was acquired in 1988 by the VIC Government, and consisted of 2001 line-kilometres of data at 250m line spacing and 80m terrain clearance. The grid was produced by applying the colours red to the Potassium ground concentration, green to the Thorium concentration and blue to the Uranium concentration. The colours were clipped to a 99% linear scale. These colours were transparent over a shaded Total Count. This clipping will necessarily introduce some artefacts into the ratio grids in areas of very low radioelement concentrations. The 3-band image was superposed on the sun shaded TC grid of the same survey to produce the final image.

This GSV Pitfield Plains Vic pot tho ura totg 4band radiometric grid geodetic is an airborne-derived radiometric Potassium, Thorium and Uranium data over a sun shaded total count radiometric data for the Pitfield Plains, Vic, 1987 (GSV1759). 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 uranium (K), uranium (U) and uranium (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 GSV Pitfield Plains Vic pot tho ura totg 4band radiometric grid geodetic has a cell size of 0.0005 degrees (approximately 49m). The data used to produce this grid was acquired in 1987 by the VIC Government, and consisted of 1295 line-kilometres of data at 250m line spacing and 80m terrain clearance. The grid was produced by applying the colours red to the Potassium ground concentration, green to the Thorium concentration and blue to the Uranium concentration. The colours were clipped to a 99% linear scale. These colours were transparent over a shaded Total Count. This clipping will necessarily introduce some artefacts into the ratio grids in areas of very low radioelement concentrations. The 3-band image was superposed on the sun shaded TC grid of the same survey to produce the final image.

This GSV East Gippsland Vic pot tho ura totg 4band radiometric grid geodetic is an airborne-derived radiometric Potassium, Thorium and Uranium data over a sun shaded total count radiometric data for the East Gippsland, Vic, 1998 (GSV3077). 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 uranium (K), uranium (U) and uranium (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 GSV East Gippsland Vic pot tho ura totg 4band radiometric grid geodetic has a cell size of 0.0005 degrees (approximately 49m). The data used to produce this grid was acquired in 1998 by the VIC Government, and consisted of 16736 line-kilometres of data at a line spacing between 200m and 400m, and 75m terrain clearance. The grid was produced by applying the colours red to the Potassium ground concentration, green to the Thorium concentration and blue to the Uranium concentration. The colours were clipped to a 99% linear scale. These colours were transparent over a shaded Total Count. This clipping will necessarily introduce some artefacts into the ratio grids in areas of very low radioelement concentrations. The 3-band image was superposed on the sun shaded TC grid of the same survey to produce the final image.

This GSV Healesville South Vic pot tho ura totg 4band radiometric grid geodetic is an airborne-derived radiometric Potassium, Thorium and Uranium data over a sun shaded total count radiometric data for the Healesville South, Vic, 2001 (GSV3181). 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 uranium (K), uranium (U) and uranium (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 GSV Healesville South Vic pot tho ura totg 4band radiometric grid geodetic has a cell size of 0.0005 degrees (approximately 49m). The data used to produce this grid was acquired in 2001 by the VIC Government, and consisted of 5584 line-kilometres of data at 250m line spacing and 80m terrain clearance. The grid was produced by applying the colours red to the Potassium ground concentration, green to the Thorium concentration and blue to the Uranium concentration. The colours were clipped to a 99% linear scale. These colours were transparent over a shaded Total Count. This clipping will necessarily introduce some artefacts into the ratio grids in areas of very low radioelement concentrations. The 3-band image was superposed on the sun shaded TC grid of the same survey to produce the final image.