(See related photo: "'Polar Predator' Dino Tracks Found" [October 23, 2007].)
Using data collected by Australia's national geoscience agency and Russia's Okeangeologia Institute, however, the team found that Australia fit against Antarctica more than 310 miles (500 kilometers) further east than was previously believed.
This discovery led the scientists to identify the change in Australia's course of direction and the chain reaction that caused it.
Gaku Kimura, a professor of earth science at the University of Tokyo, said the work of the Sydney team was "interesting because it is really controversial."
The new theory suggests that the ancient event is what caused a previously unexplained bend in an underwater mountain range known as the Hawaii-Emperor range, he explained.
Scientists had been perplexed at the geological processes that had caused the unusual formation.
Secondly, he pointed out, the "classical" interpretation of the timeline for these events put them at around 43 million years ago, a date that has been revised to around 50 million years ago in the new research.
Whittaker believes the new model has far-reaching implications for understanding the creation of natural resources in waters around present-day Australia, as well as the chain of volcanoes known as the "Ring of Fire" that circles the Pacific.
"Natural resources form under specific conditions where the timing and amounts of heat and stress are crucial," Whittaker said.
"This will help locate natural resources, especially on the southern margin of Australia.
"Understanding how the plates moved will also provide a better base for climate models, which in turn help our understanding of present-day climate," she added.
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