Australia, despite being a massive island and continent of its own, has only one active volcanic region, and this spot has seen about 400 volcanic events in the last four million years. Now researchers have discovered the unique process that allows these eruptions to occur in a portion of the globe that is nearly devoid of volcanic activity.
"Volcanoes in this region of Australia are generated by a very different process to most of Earth's volcanoes, which occur on the edges of tectonic plates, such as the Pacific Rim of Fire," researcher Rhodri Davies, from the Research School of Earth Sciences at the Australian National University, explained in a statement.
"We have determined that the volcanism arises from a unique interaction between local variations in the continent's thickness, which we were able to map for the first time, and its movement, at seven centimeters a year northwards towards New Guinea and Indonesia," he added.
According to a study that was recently published in the journal Geology, Davies and his colleagues determined this after taking measurements of the 310 mile (500 km) volcanic region. They used the National Computational Infrastructure's supercomputer Raijin to create a state-of-the art 3-D model of the region's geological features.
And this model showed that the region is pretty shallow, less than 200 kilometers deep, in an area where a 2.5-billion-year-old part of the continent meets a thinner, younger section, formed in the past 500 million years or so.
The varied thicknesses draw heat from deeper in the mantle up to the surface, and Australia's slow northward drift helps create a superheated spot in the region, creating magma.
"There are around 50 other similarly isolated volcanic regions around the world, several of which we may now be able to explain," Davies added excitedly.
He and his colleagues now plan to used the same modeling techniques on these other mysterious regions around the world.