<div>Geoscience Australia (GA), in collaboration with the New South Wales (NSW) Government’s Geological Survey of NSW, undertook a horizontal magnetic gradient and radiometric survey in the Yathong area of NSW. This survey was fully funded by the NSW Government as part of a project to find deep groundwater for use in times of drought.</div><div><br></div><div>Survey Name: Yathong</div><div>Datasets Acquired: Horizontal Magnetic Gradient, Radiometrics, and Elevation</div><div>Geoscience Australia Project Number: P5023</div><div>Acquisition Start Date: 21/05/2023</div><div>Acquisition End Date: 14/09/2023</div><div>Flight line spacing: 200 m</div><div>Flight line direction: East-West (090-270 degrees)</div><div>Total distance flown: 65,503.75 line-km's</div><div>Nominal terrain clearance: 80 m</div><div>Data Acquisition: Magspec Airborne Surveys Pty Ltd</div><div>Project Management: Geoscience Australia</div><div>Quality Control: Geoscience Australia</div><div>Dataset Ownership: Geological Survey of New South Wales</div><div>Datum: Geocentric Datum of Australia 2020 (GDA2020)</div><div>Projection: Map Grid of Australia Zone 55 (MGA55)</div><div><br></div><div>Included in this release:</div><div><br></div><div>1. Point-located Data - ASCII-column (.dat) and NetCDF (.nc) format.</div><div>• Magnetic diurnal;</div><div>• Magnetic gradient raw-edited;</div><div>• Magnetic gradient reduced;</div><div>• Radiometrics raw-edited;</div><div>• Radiometrics reduced.</div><div><br></div><div>2. Gridded data - ERMapper (.ers) format.</div><div>• Gradient enhanced Total Magnetic Intensity (TMI);</div><div>• Gradient enhanced TMI Reduced to Pole (RTP);</div><div>• Gradient enhanced TMI RTP with First Vertical Derivative (1VD);</div><div>• Dose rate (with NASVD and standard processing);</div><div>• Potassium concentration (with NASVD, standard processing);</div><div>• Thorium concentration (with NASVD, standard processing);</div><div>• Uranium concentration (with NASVD, standard processing);</div><div>• Radar-derived digital elevation model (geoidal).</div><div><br></div><div>3. Reports.</div><div>• Calibration report;</div><div>• Operations and processing summary report.</div>

Survey Name: Cobar magnetic and radiometric survey, 2021 Datasets Acquired: Magnetics, Radiometrics and Elevation Geoscience Australia Project Number: P5009 Acquisition Start Date: 8/06/2021 Acquisition End Date: 10/08/2021 Flight line spacing: 200 m Flight line direction: East-West (090-270) Total distance flown: 53,617 line-km Nominal terrain clearance: 60 m Blocks: 7 Data Acquisition: Magspec Airborne Surveys Project Management: Geoscience Australia Quality Control: Baigent Geosciences P.L. on behalf of Geoscience Australia Dataset Ownership: Geological Survey of NSW and Geoscience Australia Included in this release: 1. Point-located Data ASCII-column data with accompanying description and definition files. • Magnetics corrected i. Magnetic data with corrections for diurnal, IGRF, tie-levelling, micro-levelling. ii. Elevation data converted to geoidal values and a digital elevation model. • Radiometrics corrected i. Equivalent ground concentrations of radioelements with and without NASVD spectral filtering and standard IAEA processing, pressure, temperature and survey altitude. 2. Grids Gridded data in ERMapper (.ers) format (GDA94, MGA55). • Total magnetic intensity (TMI). • TMI reduced to pole (RTP). • TMI RTP with first vertical derivative applied. • Dose rate (with NASVD and standard processing). • Potassium concentration (%, with NASVD, standard processing). • Thorium concentration (ppm, with NASVD, standard processing). • Uranium concentration (ppm, with NASVD, standard processing). • Radar-derived digital elevation model (geoidal). 3. Images Data in tagged image format (TIF), (GDA94, MGA55). • Total magnetic intensity (TMI). • TMI reduced to pole (RTP). • TMI RTP with first vertical derivative applied. • Dose rate (with NASVD and standard processing). • Potassium concentration (% with NASVD, standard processing). • Thorium concentration (ppm, with NASVD, standard processing). • Uranium concentration (ppm, with NASVD, standard processing). • Radar-derived digital elevation model (geoidal). 4. Reports • P5009_2585_V3_GA_Cobar_Logistics_Report • P5009_BGS_GA_CobarQCReport © Geological Survey of New South Wales and Commonwealth of Australia (Geoscience Australia) 2021. With the exception of the Commonwealth Coat of Arms and where otherwise noted, this product is provided under a Creative Commons Attribution 4.0 International License. (http://creativecommons.org/licenses/by/4.0/legalcode).

Total magnetic intensity (TMI) data measures variations in the intensity of the Earth 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 2019 Total magnetic Intensity (TMI) grid of Australia has a grid cell size of ~3 seconds of arc (approximately 80 m). This grid only includes airborne-derived TMI data for onshore and near-offshore continental areas. Since the sixth edition was released in 2015, data from 234 new surveys have been added to the database, acquired mainly by the State and Territory Geological Surveys. The new grid was derived from a re-levelling of the national magnetic grid database. The survey grids were levelled to each other, and to the Australia Wide Airborne Geophysical Survey (AWAGS), which serves as a baseline to constrain long wavelengths in the final grid. It is estimated that 33 500 000 line-kilometres of survey data were acquired to produce the 2019 grid data, about 2 000 000 line-kilometres more than for the previous edition.

Survey Name: East Tasmania Datasets Acquired: Magnetics, Radiometrics and Elevation Geoscience Australia Project Number: P5020 Acquisition Start Date: 20/03/2022 Acquisition End Date: 23/06/2022 Flight line spacing: 200 m Flight line direction: East-West (090-270) Total distance flown: 57,709 line-km's Nominal terrain clearance: 80 m Data Acquisition: Magspec Airborne Surveys Pty Ltd Project Management: Geoscience Australia Quality Control: Geoscience Australia Dataset Ownership: Geoscience Australia and Mineral Resources Tasmania Datum: Geocentric Datum of Australia 2020 (GDA2020) Projection: Map Grid of Australia 55 (MGA55) Included in this release: 1. Point-located Data - ASCII-column (.dat) or NetCDF (.nc) format. • Magnetic diurnal; • Magnetics raw-edited; • Magnetics reduced; • Radiometrics raw-edited; • Radiometrics reduced. 2. Gridded data - ERMapper (.ers) format. • Total magnetic intensity (TMI); • TMI reduced to pole (RTP); • TMI RTP with first vertical derivative (1VD) applied; • Dose rate (with NASVD and standard processing); • Potassium concentration (with NASVD, standard processing); • Thorium concentration (with NASVD, standard processing); • Uranium concentration (with NASVD, standard processing); • Radar-derived digital elevation model (geoidal). 3. Reports. • Calibration report; • Operations and processing summary report. © Commonwealth of Australia (Geoscience Australia) and Mineral Resources Tasmania, Government of Tasmania 2022. With the exception of the Commonwealth Coat of Arms and where otherwise noted, this product is provided under a Creative Commons Attribution 4.0 International Licence (http://creativecommons.org/licenses/by/4.0/legalcode).

<div>This document defines the technical standards set by Geoscience Australia for the acquisition, processing and supply of airborne magnetic, horizontal magnetic gradient and radiometric (gamma-ray spectrometric) data. The technical standards cover the requirements for equipment, calibrations, quality control checks, reporting and data formats for airborne surveys.</div><div><br></div><div><br></div><div><strong>Table of Contents</strong></div><div><br></div><div>Attachment 1A – Data Acquisition and Processing</div><div><br></div><div>1 Aircraft</div><div>2 Flight and Tie Lines</div><div>3 Global Navigation Satellite System (GNSS)</div><div>4 Parallax Correction</div><div>5 Altimeter</div><div>6 Barometer</div><div>7 Digital Elevation Model</div><div>8 Magnetic System Equipment</div><div>9 Magnetic Gradient System Equipment</div><div>10 Magnetic / Gradient Calibration and Quality Tolerances</div><div>11 Magnetic Base Station (Diurnal Monitoring)</div><div>12 Magnetic Data Reduction</div><div>13 Magnetic Gradient Data Reduction</div><div>14 Radiometric System Equipment</div><div>15 Radiometric Calibration and Quality Tolerances</div><div>16 Radiometric Data Reduction</div><div><br></div><div>Attachment 1B – Reporting and Data Supply</div><div><br></div><div>1 General</div><div>2 Calibration Report</div><div>3 Daily Acquisition Report</div><div>4 Weekly Acquisition Report</div><div>5 Operations and Processing Summary Report</div><div>6 Supply Schedule</div><div><br></div><div>Attachment 1C – Data Formats</div><div><br></div><div>1 General</div><div>2 Point-Located Data Files</div><div>3 Definition Files</div><div>4 Description Files</div><div>5 Raw-Edited Magnetic Data File</div><div>6 Reduced Magnetic Data File</div><div>7 Diurnal Magnetic Data File</div><div>8 Raw-Edited Magnetic Gradient Data File</div><div>9 Reduced Magnetic Gradiometry Data File</div><div>10 Raw-Edited Radiometric Data File</div><div>11 Reduced Radiometric Data File</div><div>12 Gridded Data Files</div><div>13 Image Enhanced GeoTIFF Files