Depth to the Mohorovičić discontinuity (Moho) interpreted and modelled by Geognostics with support from government and industry. The Moho surface is the boundary between the Earth's crust and the upper mantle. The depth to moho is a representation of the thickness of the Earth's Crust. This moho surface is derived from seismic, gravity and other geophysical datasets.

Please view Matthews and Sheldon (2024) for full description and instructions: Contact Sam at samuel.matthews@regional.nsw.gov.au if you have any difficulty accessing the paper.

Geothermal gradient model (2023) created by Geognostics with support from government and industry. The geothermal gradient describes how temperature increases with depth inside the Earth. It is expressed in degrees Celsius per kilometre (°C/km). The linear geothermal gradients are from the top of SEEBASE to the surface. These were calculated using the combined heat-flow contribution of multiple crustal heat sources including upper mantle, radiogenic upper crust, and sediment thickness. The highest calculated geothermal gradients are generally related to areas interpreted to be underlain by granitic intrusions in the basement. The composition and heat production characteristics of the granites are largely unconstrained by analyses

The Geological Survey of NSW developed a Seamless Geology of UTM Zone 56 during 2014 as part of a project to develop a seamless vector geology dataset of the best available geological mapping data covering the whole of NSW.The overarching aims of the Statewide Seamless Geology Project were to: (i) compile the different original scales, formats and rock unit naming conventions into a consistent, statewide format; (ii) edge-match the geology across existing map sheets; and (iii) interpret the basement geology under cover. The resulting geodatabase comprises a series of layers which include: (i) solid basement geology; (ii) cover rocks (defined as undeformed and unmetamorphosed); (iii) Mesozoic igneous rocks; and (iv) Cenozoic sedimentary and igneous rocks. The project was divided into 3 major stages corresponding to the UTM zones which divide New South Wales. This dataset includes the seamless geology layers from the NSW portion of UTM Zone 56 (ie.east of 150 degrees longitude to the coast).

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.

Isostatic residual Bouguer gravity image overlain on tilt-filtered total magnetic intensity reduced to the pole (Tilt TMI RTP) image. The image is a partially-transparent pseudocolour layer of Isostatic residual Bouguer gravity, with a histogram-equalised colour-stretch, overlain on a greyscale intensity layer of the Tilt TMI RTP, with a histogram-equalised stretch. 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 variations in the thickness of the Earth’s crust due to changes in topography. The tilt-angle filter of total magnetic intensity produces a local positive maximum over a magnetic source and is zero near the edge of the source, and is useful for tracing geological structure below variable depths of cover.

The Geological Survey of NSW developed a Seamless Geology of UTM Zone 56 during 2014 as part of a project to develop a seamless vector geology dataset of the best available geological mapping data covering the whole of NSW.The overarching aims of the Statewide Seamless Geology Project were to: (i) compile the different original scales, formats and rock unit naming conventions into a consistent, statewide format; (ii) edge-match the geology across existing map sheets; and (iii) interpret the basement geology under cover. The resulting geodatabase comprises a series of layers which include: (i) solid basement geology; (ii) cover rocks (defined as undeformed and unmetamorphosed); (iii) Mesozoic igneous rocks; and (iv) Cenozoic sedimentary and igneous rocks. The project was divided into 3 major stages corresponding to the UTM zones which divide New South Wales. This dataset includes the seamless geology layers from the NSW portion of UTM Zone 56 (ie.east of 150 degrees longitude to the coast).

The petrophysics database contains petrophysical (rock physical properties) data managed and acquired by the Geological Survey of NSW (GSNSW). Petrophysical properties recorded are: magnetic susceptibility (volume normalised); principal axes and degree of anisotropy of magnetic susceptibility; natural remanent magnetisation (NRM) intensity and direction; remanent magnetisation component directions; Koenigsberger (Q) ratio; saturated density; dry density; grain density; porosity. Vector and tensor magnetic properties (remanence and AMS) are oriented to in-situ (geographic) and fold-corrected (stratigraphic) coordinates where sample and bedding orientation are known.

AEM curtains are a set of cross-sections generated using geophysical inversion to convert AEM data to conductivity (m/S) versus depth below surface (m). These data represent the conductivity of soil and rocks to a depth of about 400 m. A pseudocolour-stretch has been applied to the data. Blue represents low conductivity values and red represents high values. The colours vary due to; (1) natural variations in the electrical properties of soils, rocks, minerals and groundwater, (2) man-made structures, radio-transmissions and lightning strike and (3) AEM system artefacts.

The NSW Seamless Geology Project was originally a five-year initiative of the Geological Survey of New South Wales which commenced in late 2013 and aimed to provide a statewide compilation of the best available digital geological mapping data in an internally consistent format. The overarching aims of the NSW Seamless Geology Project were to: (i) compile the different original scales, formats and rock unit naming conventions into a consistent, statewide format; (ii) edge-match the geology across existing map sheets; and (iii) interpret the basement geology under cover. The resulting geodatabase comprises a series of layers which include: (i) solid basement geology; (ii) cover rocks (defined as undeformed and unmetamorphosed); (iii) Mesozoic igneous rocks; and (iv) Cenozoic sedimentary and igneous rocks. Due to the size of the project, the work was divided into UTM zones, starting in the east with Zone 56, then moving west to Zone 54, and finishing with Zone 55. The western half of Zone 55 was completed in 2018, after which the results were merged with the previously completed Zones to produce version 1 of the NSW Seamless Geology dataset. Completion of this stage saw the end of phase 1 of the Seamless Geology Project, but it is intended that the Seamless Geology dataset will be continually updated and refined as new digital geological mapping data becomes available. Updates to the Seamless Geology dataset generally occur on an annual basis. Version 2.6 is the 8th major update to the NSW Seamless Geology and was released in 2026. This release includes major remapping of the northern Rockley–Gulgong Volcanic Belt; a significant upgrade to the mapping of Broughton Island; significant updates to the Lachlan Orogen and Cenozoic Sedimentary Province in the Canbelego 1:100,000 map sheet area; and attribute updates, data additions, and minor error fixes to all layers. Murray Basin During editing for version 2.1 of the Seamless Geology, the Cenozoic Murray Basin of southwest NSW was divided into its constituent units (formation or group level), with particular emphasis on the Loxton Sands, an economically significant unit containing numerous heavy mineral sand placer deposits and a number of mines producing rutile, zircon, and ilmenite. The Murray Basin linework was edited to reconcile the data with mapping in the existing NSW Seamless Geology dataset. See the lineage section for further details.