The NSW Mine Reuse project investigated the occurrence of critical metals in mining waste material. It involved a preliminary geochemical and mineralogical characterisation study across multiple metalliferous and coal sites on various waste material types, aiming to identify subsequent secondary prospectivity opportunities. The study was completed in collaboration between the Geological Survey of NSW, the Sustainable Minerals Institute at The University of Queensland, Geoscience Australia and RMIT University. The program consisted of hand-auger drilling and sample collection from various waste sources, including tailings, waste rock, slags, coal rejects and fly ash. Each sample then underwent a 48-element geochemical analysis, with targeted mineralogy and mineral chemistry conducted on selected samples to better understand the distribution of elevated critical elements.

The Central NSW 10 metre grid package is a dataset containing best available open-file geophysical data spanning twelve 1:250,000 geological mapsheets, from Cobar in the northwest to Bathurst in the southeast. Available within the package are merged grids and high resolution imagery providing excellent geophysical coverage of the region. Gridded products include: • Digital Elevation Model (DEM) • Total Magnetic Intensity (TMI) • Total Magnetic Intensity Reduced to The Pole (TMI RTP) • Total Magnetic Intensity Reduced to The Pole First Vertical Derivative (TMI RTP 1VD) • Total Magnetic Intensity Reduced to The Pole Second Vertical Derivative (TMI RTP 2VD) • Total Magnetic Intensity Reduced to The Pole Tilt Angle Filter (TMI RTP Tilt) • Potassium Percentage (Kperc) • Thorium Parts Per Million (Thppm) • Uranium Parts Per Million (Uppm) • Radiometric K-Th-U Ternary (KThU) • Radiometric Dose Rate (Dose) • Thorium divided by Potassium (ThdivK) • Uranium divided by Potassium (UdivK) • Uranium divided by Thorium (UdivTh) • Uranium Squared divided by Thorium (U2divTh) • Isostatically Corrected Bouguer Gravity (Iso Grav) Images for each grid are also available, with the addition of: • DEM (Terrain) • TMI RTP overlaid on TMI RTP Tilt • Iso Grav overlaid on TMI RTP Tilt

Greyscale image of second vertical derivative (2VD) of total magnetic intensity reduced to the pole (TMI RTP). Darker tones indicate lower values and lighter tones represent higher values. Reduction to the pole filters magnetic anomalies to appear as if the Earth's magnetic field were locally vertical, as at the magnetic pole (assuming all magnetic sources are inductively magnetised). The 2VD filter shows the vertical rate of change in the first vertical derivative (1VD) of the Earth's total magnetic field and enhances boundaries and structural detail of shallow sources further than 1VD. The 2VD filter enhances magnetic textures in the image, however, it also amplifies non-geological noise. Variations in the magnetic field are caused by lithological factors, principally magnetite (and/or pyrrhotite) content. This Statewide image was generated by merging many individual airborne magnetic surveys.

Pseudocolour image of the ratio between uranium and thorium within the upper 20 centimetres of the ground. This image was generated using normalised input grids to avoid ‘divide by zero’ errors. Cooler colours indicate lower abundances of uranium relative to thorium and warmer colours represent the opposite. Variations in U/Th ratio are caused varied mineral compositions in host rocks and soils. This statewide image was generated by merging many individual airborne radiometric surveys.

Pseudocolour image of isostatic residual gravity with a histogram-equalised colour-stretch. Cooler colours indicate lower gravity values and warmer colours represent higher values. The image has been enhanced with a 3×3 sun filter with the sun illumination set at 45 degrees elevation and 90 degrees azimuth. Bouguer gravity compensates for variations in latitude, 'free-air' elevation and Bouguer correction (assuming a crustal density of 2.67 T/m³). The isostatic correction removes the effect of the thickness of Earth’s crust due to changes in topography. Attention: Please ensure your version of the NSW gravity merges contains the date ‘2024-10-30’ in their filename. An update was made to remedy location errors in the initial release. Apologies for any inconvenience.

Greyscale image of the tilt-angle filter (Tilt) of total magnetic intensity, reduced to the pole (TMI RTP). Darker tones indicate lower values and lighter tones represent higher values. Reduction to the pole filters magnetic anomalies to appear as if the Earth's magnetic field were locally vertical, as at the magnetic pole (assuming all magnetic sources are inductively magnetised). The Tilt filter produces a positive maximum over the centre of a magnetic source and is zero near the edge of the source, and is useful for tracing geological structure below variable depths of cover. Variations in the magnetic field are caused by lithological factors, principally magnetite (and/or pyrrhotite) content. This Statewide image was generated by merging many individual airborne magnetic surveys.

Greyscale image of first vertical derivative (1VD) of Bouguer gravity. Darker tones indicate lower values and lighter tones represent higher values. Bouguer gravity compensates for variations in latitude, 'free-air' elevation and Bouguer correction (assuming a crustal density of 2.67 T/m³). Attention: Please ensure your version of the NSW gravity merges contains the date ‘2024-10-30’ in their filename. An update was made to remedy location errors in the initial release. Apologies for any inconvenience.

Ternary radioelement potassium(K)-thorium(Th)-uranium(U) channel data. The image was generated by merging many individual airborne surveys and is a red-green-blue (RGB) composite using a histogram-equalised colour-stretch for each of the three channels. The red, green and blue channels represent K, Th and U respectively. Mixed compositions are indicated by the proportional blend of the corresponding additive primary colours (e.g. yellow indicates the presence of both K and Th, magenta the presence of K and U while aqua indicates the presence of Th and U). Black indicates low concentrations and white represents high concentrations for all three radioelements. The distribution of radioelements reflects the geochemistry and mineralogy of the near-surface, which may constitute either bedrock or regolith materials. The NSW statewide grid DVD set includes K values in percent(%), Th values in parts per million (ppm) and U values in parts per million (ppm). This dataset is part of the Geological Survey NSW State Geophysics data set series.

Pseudocolour image of the percentage of potassium (K%) in the upper 20 centimetres of the ground. Cooler colours indicate lower abundances of potassium and warmer colours represent higher abundances. Variations in potassium values are caused by varied mineral compositions in host rocks and soils. This statewide image was generated by merging many individual airborne radiometric surveys.

Elevation is a pseudocolour layer with a histogram-equalised colour stretch. Cooler colours indicate lower values and warmer colours represent increasingly higher elevation. Elevation is derived from 5 metre LiDAR coverage of NSW and has been resampled to a uniform 25 metre grid cell size.