Pseudocolour image of the ratio between uranium and thorium within the upper 20 centimetres of the ground. Cooler colours indicate lower abundances of uranium relative to thorium and warmer colours represent the opposite. Variations in U2/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 the ratio between thorium and potassium 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 thorium relative to potassium and warmer colours represent the opposite. Variations in Th/K ratio are caused varied mineral compositions in host rocks and soils. This statewide image was generated by merging many individual airborne radiometric surveys.

The semi-transparent isostatic residual gravity image is displayed using cooler colours (blue) to indicate lower gravity values and warmer colours (red) represent higher values. The underlying greyscale tilt-angle filtered total magnetic intensity image that has been reduced to the pole (Tilt TMI RTP). The tilt-angle filter of the total magnetic intensity produces a local positive maximum (white) over a magnetic source and is zero near the edge of the source (grey), and is useful for tracing geological structure below variable depths of cover. Both image layers were generated using a histogram-equalised colour-stretch. 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 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.

Pseudocolour image of total magnetic intensity reduced to the pole (TMI RTP) with a histogram-equalised colour-stretch. Cooler colours indicate lower magnetic intensity values and warmer colours represent higher values. The intensity layer is the TMI RTP greyscale image enhanced by a 3x3 sun filter with the sun illumination set at 45 degrees elevation and 90 degrees azimuth. 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). 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 isostatic residual gravity (Iso-grav). The 1VD filter shows the rate of change in the isostatic gravity data. Darker tones indicate lower values and lighter tones represent higher values. 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 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.

Total magnetic intensity reduced to the pole (TMI RTP) image overlain on tilt-filtered (Tilt) total magnetic intensity reduced to the pole image. The image is a partially-transparent pseudocolour layer of TMI RTP, with a histogram-equalised colour-stretch, overlain on a greyscale intensity layer of the Tilt, with a histogram-equalised stretch. Cooler colours indicate lower values and warmer colours represent higher TMI RTP values. Dark tones indicate lower values and lighter tones represent higher values of the Tilt. 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-angle 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 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.