b'Geophysics in the surveys NewsMineral Resources Tasmania: Tiers airborne magnetic and radiometric survey data releasedThe data obtained by the Tiers airborneare very feature-rich, revealing a greatMinty and Ross Brodie (2015). With magnetic and radiometric survey indeal about both surface geology andvertical relief well in excess of 1 km February-April 2021 have now beendeeper features. The most strikingacross the survey area, this has resulted finalised and are available for downloadcontrasts in the radiometric image arein significant improvements. More detail via the Mineral Resources Tasmaniabetween relatively high thorium andappears in the Geoscience Australia (https://www.mrt.tas.gov.au/) anduranium (cyan) associated with Cenozoicupdate in this edition of Preview.Geoscience Australia (http://www. sediments of the Longford Basin in the ga.gov.au/) websites. As outlined in thecentre, against the more subdued butReferencelast edition of Preview, due to the highlypotassium-dominated (reddish) signal variable topography the survey was flownof Jurassic dolerite intrusions mainly toMinty, B and Brodie, R., 2015. The 3D with a combination of fixed wing andthe east and west. The dolerites togetherinversion of airborne gamma-ray helicopter platforms, on 200 m-spacedwith Cenozoic basalts are responsiblespectrometric data. Extended Abstract, east-west flight lines at a nominal terrainfor much (though notably not all) of theASEG 24th International Geophysical clearance of 80 m. The project was ahighly magnetic character visible. Conference and Exhibition, Perth, 15 - collaboration between MRT and GA, withThe radiometric data have been18 February 2015.both organisations contributing fundingprocessed to regular grids of equivalent and GA overseeing contractors MagSpec. radioelement concentration via the fullMark Duffett As shown in Figures 1 and 2, both the3D inversion (including topographicMineral Resources Tasmania magnetic and radiometric data setscorrection) method developed by Brianmark.duffett@stategrowth.tas.gov.auFigure 1.3D-inverted ternary image of radioelement equivalent ground concentration, histogram equalised. Red = potassium, green = thorium, blue = uranium. The background image is the MRT statewide 10 m digital elevation model.Figure 2.Total magnetic intensity reduced to pole, with first vertical derivative intensity overlay. The background image is the MRT statewide 10 m digital elevation model.27 PREVIEW AUGUST 2021'