Example of surfaces available as part of the Sydney-Gunnedah Basins 3D Stratigraphic Model Package

A basin-scale structural and stratigraphic 3D model has been developed for the Sydney and Gunnedah basins in New South Wales, Australia.

The integrated Sydney-Gunnedah basins 3D model was developed to advance the understanding of the geological and structural setting of the region. The basins have a strike length of approximately 700 kilometres, a maximum width of over 300 kilometres and extend to a maximum estimated depth of 15 kilometres. Both basins are bound by the crustal scale Hunter-Mooki Fault to the east and the Lachlan Orogen (Lachlan Fold Belt) to the west. Having been compressed in their early stages, sediment-folding events in the basins are generally light and the trend of fold axes is generally oriented SSE-NNW. Detailed examination of stratigraphic relationships during modelling has allowed recognition of the major transgression and regression events.

The model will contribute to the advances in the understanding of regional sub-surface geology, cover thickness and character; and illustrates the depositional and deformational style across the basin, with its structurally complex systems of folding and faulting. The model also shows the effect of distinct changes in sea levels and depositional environments, alongside the structural architecture and fault movements.

The model is delivered as a set of surfaces developed by integrating the surface mapping, seamless geology, reflection seismic profiles and petroleum, coal, minerals and water well data. Due to the regional scale, horizon modelling was limited to geological groups, subgroups and key lithological boundaries. The model enables the user to have a quick and easy way to assessing the subsurface geology anywhere in the basins and provides a geological framework for future detailed modelling.

Contributing authors

F. Wierzynski de Oliveira, J.D. Davidson

Projection system

GDA 1994 Zone 56

Model extent

Max_X:  411120mE

Min_X:  70200mE

Max_Y:  6736500mN

Min_Y:  6052500mN

Max_Z:  1600m

Min_Z:  -8000m


Release was in August 2017; updates will be ongoing as additional constraining data is obtained.


Wierzynski de Oliveira, F. & Davidson, J. 2017. 3D Geological Model of the Sydney - Gunnedah Basin, NSW - Australia [digital dataset]. Geological Survey of New South Wales, Maitland.

File origin software



John Davidson, Senior Geologist - 3D specialist