PurposeThis package comprises a set of 86 thematic grids (rasters) derived from national coverages of gravity and magnetic survey data. These datasets provide valuable information about the distribution of geological features, physical property variations, and the composition of the Earth's crust. All grids have been resampled to the same cell size, map extent, and projection to allow them to be integrated into predictive mapping and modelling workflows using machine learning. Users can download individual grids or the whole grid package.  Input DataThe following Australian national datasets were used:1.     2019 Australian National Gravity Grids: Free Air Anomaly, Complete Bouguer Anomaly, De-trended Global Isostatic Residual, 400 m cell size (Lane et al., 2020).2.     Total Magnetic Intensity (TMI) Grid of Australia 2019 - seventh edition Enhanced Products Package (Morse, 2020).
ProcessingAll processing of the national grids were undertaken using Intrepid software. The following was performed on the input data:1.     The grids were reprojected from GDA94 geodetic to Australian Albers (EPSG 3577). 2.     The grids were aligned to the same grid cell registration point and interpolated to fit within an 80 m cell size using a cubic spline method to ensure that the cell locations for all images are common.3.     Various Fast Fourier Transforms (FFT) were applied to each grid (see ‘Grids_for_Machine_Learning_dataset_notes.pdf’).  Metadata (all grids)·       Datum: GDA94·       Projection: Australian Albers (EPSG 3577)·       Cell size: 80 m·       File format: GeoTiff (.tif)Data is available on request from [email protected] - Quote eCat# 149130

The Blackall Airborne Gravity Gradiometer (AGG) survey of Central Queensland was flown between March 11th to 6th April 2024. Contracted to Xcalibur Smart Mapping, Geoscience Australia undertook the project management, contract management and quality control on behalf of the Geological Survey of Queensland. The located data, gridded data and quality control reports are contained within this record.Survey area was centered on longitude 147° 21’ E and latitude 25° 16’ S to the south of Blackall. A total of 34 production flights were flown for a combined total of 15,705.4 line kilometres of data and acquired on 1000 m line spacing at 100 m nominal terrain clearance. Quality control was performed by airborne gravity consultant Dr Mark Dransfield on behalf of Geoscience Australia, with his report included here.The survey was designed to supplement the regional legacy ground gravity data and improve the definition of gravimetric anomalies in the region. In addition, the AGG survey will provide better understanding of the cover sequence thickness and characteristics of the underlying basement geology.The data will be released by the Geological Survey of Queensland and can be found at: https://geoscience.data.qld.gov.au/data/gravity-gradiometry/gg104288.Survey Name: Blackall airborne gravity gradiometery survey, 2024Datasets Acquired: Gravity gradiometry, gravity, digital terrain modelGeoscience Australia Project Number: P5024Acquisition Start Date: 11/03/2024Acquisition End Date: 06/04/2024Flight line spacing: 1000 mFlight line direction: East-West (090-270)Total distance flown: 15,705.4 line kmNominal terrain clearance: 100 mBlocks: 1Data Acquisition: Xcalibur Smart MappingProject Management: Geoscience AustraliaQuality Control: Mark Dransfield on behalf of Geoscience AustraliaDataset Ownership: Geological Survey of Queensland and Geoscience AustraliaIncluded in this release:1. Point-located DataASCII-column data in ASEG-GDF format with accompanying description and definition files.• Gravity gradiometry data including the various corrections• Gravity gradiometry data noise estimates• Vertical gravity estimate including various reduction and levelled corrections• Digital terrain model2. GridsGridded data in ERMapper (.ers) format (GDA2020/MGA zone 55):• Free-air vertical gravity gradiometry• Free-air corrected vertical gravity• Terrain and bouguer corrected vertical gravity gradiometry (densities for terrain correction: 2.0g/cm3 and 2.67 g/cm3)• Terrain and bouguer corrected vertical gravity (densities for terrain correction: 2.0g/cm3 and 2.67 g/cm3)• Conformed, terrain and bouguer corrected vertical gravity gradiometry (densities for terrain correction: 2.0g/cm3 and 2.67 g/cm3)• Conformed, terrain and bouguer vertical gravity (densities for terrain correction: 2.0g/cm3 and 2.67 g/cm3)• Digital terrain model3. Reports• Contractors Logistics Report• Quality Control Report (Mark Dransfield)

The Etheridge Airborne Gravity Gradiometer (AGG) survey of Northern Queensland was flown between April 8th to 1st June 2024. Contracted to Xcalibur Smart Mapping, Geoscience Australia undertook the project management, contract management and quality control on behalf of the Geological Survey of Queensland. The located data, gridded data and quality control reports are contained within this record.Survey area was centered on longitude 143° 31’ E and latitude 18° 27’ S to the east of Croydon. A total of 53 production flights were flown for a combined total of 32,482.0 line kilometres of data and acquired on 1000 m line spacing at 100 m nominal terrain clearance. Quality control was performed by airborne gravity consultant Dr Mark Dransfield on behalf of Geoscience Australia, with his report included here.The survey was designed to supplement the regional legacy ground gravity data and improve the definition of gravimetric anomalies in the region. In addition, the AGG survey will provide better understanding of the cover sequence thickness and characteristics of the underlying basement geology.The data will also be released by the Geological Survey of Queensland and can be found at: https://geoscience.data.qld.gov.au/data/gravity-gradiometry/gg104290.Survey Name: Etheridge airborne gravity gradiometery survey, 2024Datasets Acquired: Gravity gradiometry, gravity, digital terrain modelGeoscience Australia Project Number: P5025Acquisition Start Date: 08/04/2024Acquisition End Date: 01/06/2024Flight line spacing: 1000 mFlight line direction: East-West (090-270)Total distance flown: 32,482.0 line kmNominal terrain clearance: 100 mBlocks: 1Data Acquisition: Xcalibur Smart MappingProject Management: Geoscience AustraliaQuality Control: Mark Dransfield on behalf of Geoscience AustraliaDataset Ownership: Geological Survey of Queensland and Geoscience AustraliaIncluded in this release:1. Point-located DataASCII-column data in ASEG-GDF format with accompanying description and definition files.• Gravity gradiometry data including the various corrections• Gravity gradiometry data noise estimates• Vertical gravity estimate including various reduction and levelled corrections• Digital terrain model2. GridsGridded data in ERMapper (.ers) format (GDA2020/MGA zone 54):• Free-air vertical gravity gradiometry• Free-air corrected vertical gravity• Terrain and bouguer corrected vertical gravity gradiometry (densities for terrain correction: 2.3g/cm3 and 2.67 g/cm3)• Terrain and bouguer corrected vertical gravity (densities for terrain correction: 2.3g/cm3 and 2.67 g/cm3)• Conformed, terrain and bouguer corrected vertical gravity gradiometry (densities for terrain correction: 2.3g/cm3 and 2.67 g/cm3)• Conformed, terrain and bouguer vertical gravity (densities for terrain correction: 2.3g/cm3 and 2.67 g/cm3)• Digital terrain model3. Reports• Contractors Logistics Report• Quality Control Report (Mark Dransfield)