Australia leads in mapping our ancient world

A world-leading tool that unwinds eons of change in the Earth’s continents and oceans has been developed in Sydney with AuScope funding.

Known as GPlates, the tool was developed by the EarthByte Group based at The University of Sydney.

GPlates is open-source software that does much more than look back in time at the movements of tectonic plates and continents. It features innovative technology that maps rises and falls in topography at any point on the Earth’s surface, as well as matching spatial points with all available geological data.

University of Sydney’s Professor of Geophysics and EarthByte founder, Dietmar Muller, said the software was a having a huge impact worldwide in understanding the Earth’s surface and deep forces in the mantle.

“GPlates existed for a number of years, but it was a small, experimental research tool. With AuScope’s support we were able to employ professional software developers and turn GPlates into a robust, industry-strength tool.

“The stability, versatility and ease of use of GPlates are three of the main reasons why it has become so popular.”

He said GPlates had been the basis of a number of recent scientific papers that made great steps forward in understanding the evolution of the Australian continent.

“The ability of GPlates, coupled to SAM mantle convection code, to reconstruct even small rises and falls in the elevation of the continent has been particularly important in a flat-lying country like Australia.

“For example, we have been able to come up with a much better understanding of how the Great Artesian Basin was flooded in the Cretaceous Period and then uplifted again.

“And we have new insights about the progressive northward sloping of continent that is resulting in the gradual submergence of the Gulf of Carpentaria and the affect that is having on coral reefs.”

The results from GPlates even found their way into mainstream prospecting, with a study on the likely location of new opal fields in the Australian outback attracting significant media attention with the release of a new prospectivity map.

“GPlates helped us develop opal prospectivity maps though time. We discovered the occurrence of opal is very tightly coupled to a particular history of the sea flooding and retreating across the island.”

In 2012 a new highly prospective opal field was discovered 75 kilometres south west of Lightning Ridge. The field is precisely in an area where the new prospectivity map suggests high opal prospectivity. This gives credence to the approach and suggests that the other areas highlighted on the map, in Queensland, New South Wales and South Australia, may be prospective for new opal fields.

Caption: Geodynamic evolution of Australia since the Cretaceous period. A GPlates visualisation shows Australia and surrounding continents at 120, 80, 40 million years ago and the present, with plate boundaries shown as thin white lines, crustal extension and basin formation indicated by meshes and deep mantle structure illustrated by cold sinking slab material (blue) and large, hot upwellings from the core-mantle boundary (red). The plate tectonic movement of Australia over the evolving mantle structure has driven the successive tilting of Australia (not shown here), first to the east in the Cretaceous period (80 Ma) when eastern Australia was underlain by the massive East Gondwana slab burial ground, driving the formation of the Great Artesian Basin. Later (between 40 million years ago and the present) Australia was tilted to the northeast when the leading edge of the northeastwards drifting continent moved over the sinking Melanesian slabs, drawing the surface down. These simulations allow us to model the formation and evolution of resource-rich sedimentary basins and form a framework for mineral exploration further back in time.

Case Study : Mapping the ancient world

Category: Simulation Analysis & Modelling