Geophysics survey data has been reported to the NSW government and released under the requirements of the NSW Mining Act 1992. Contained within this vector file is the location of surveys and acquisition parameters. These surveys use uncommon techniques.

Map blocks and map units are based on a system originally devised by the British Ordinance Survey. Each 1:1 million scale map sheet is subdivided into 3456 graticular map blocks, each measuring 5’ of latitude by 5’ of longitude. These map blocks are further subdivided into 25 1’ by 1’ map units. A map unit is approximately 3 square kilometres in size. Map blocks and map units are used in New South Wales to define certain types of titles. Petroleum exploration titles (PELs) are applied for and granted as a series of map blocks (Map sheet, block number), and mineral exploration titles, which tend to be smaller in size, are defined as a list of map units.

Locations of geotechnical reports, plans and heritage documents compiled from NSW Public Works records. These reports are considered historic records.

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.

Hydrogeochemistry is the sampling and analysis of water to test its chemical properties. The chemistry of bore water can provide clues to the properties of the underlying rocks it has flowed through. Hydrogeochemistry data provides useful information about the quality of groundwater and the processes affecting it. The data is useful for landholders and local government agencies in assessing groundwater resources and their suitability for human and animal consumption, and for industry, other government agencies and scientists to assist with targeting and assessment of natural resources in the earth’s crust. The hydrogeochemistry data presented here has been sourced from various entities including the Geological Survey of New South Wales (GSNSW), Water NSW, CSIRO, and Geoscience Australia (GA). GSNSW and GA collect hydrogeochemistry data on a project basis. CSIRO has curated a groundwater hydrochemistry dataset by collating and standardising data from most State and Territory lead water agencies. Data within NSW will be continually added to this dataset as it is collected or acquired by GSNSW in the future. The hydrogeochemistry dataset presented here includes the following data: • Field measurements and laboratory analyses, such as pH, electrical conductivity, and total dissolved solids (TDS, a measure of salinity) • Major and minor ions, such as sodium and calcium • Trace element metals and non-metals, such as gold, silver, copper and zinc • Stable and radioactive isotopes, such as oxygen-18, carbon-14, and sulphur-34 In addition to this, CSIRO has calculated variables such as saturation indices, which are derived from the hydrochemistry measurements. Information for methodologies used by CSIRO, including the saturation indices, is available from the CSIRO Research Publications Repository.

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.

This layer shows the boundary of the AusLAMP NSW survey and the station locations. Data were acquired by a collaboration between GSNSW and Geoscience Australia. Data were used to create a 3D resistivity model of the crust from 10 km depth to 200 km depth.

This layer shows a depth slice from a 3D resistivity model of the crust derived from an inversion of the AusLAMP NSW long period MT data.

In 2016, the Geological Survey of NSW (GSNSW) published a state-wide depth to basement 3D model (Robinson 2016, 2017). Since then, new geological and geophysical data have been released and used for the construction of basin-scale 3D geological models for the southern Thomson Orogen and the Sydney, Gunnedah and Bowen basins (Davidson 2019; Oliveira and Davidson 2019; Oliveira et al. 2019). The basement topography under these regions was modelled using constraints from drillholes, seismic, Seamless Geology, magnetics and gravity data. The results have now been incorporated into the updated Statewide 3D Basement Elevation Model reported herein.