Australia is known for having all kinds of curious creatures and life that might remain still undiscovered. As it turns out, this holds true too for the nation-continent's oceans: 155 miles off Sydney, researchers led by the University of New South Wales recently located a cluster of volcanoes in the sea, possibly 50 million years old.

The scientists were on Australia's new ocean-going vessel, Investigator. While looking for the nursery grounds for larval lobsters and routinely mapping the sea-floor, they ran across the volcanoes in 16,000 feet of water, a release said.

The cluster is four extinct volcanoes--they are calderas, which form after a volcano erupts and the land around it collapses to form a crater. The largest of these formations is a little under a mile across the rim and rises 2,296 feet from the sea floor, University of New South Wales said in a release.

The cluster was not found before now because the previous Marine National Facility (MNF) research ship, Southern Surveyor, only was able to map the sea floor to 9,842 feet, "leaving half of Australia's ocean territory out of reach," points out Professor Richard Arculus, of the Australian National University, who is an igneous petrologist and an expert on volcanoes, a release noted.

Finding volcanoes will yield much information on the area's geological history. "They tell us part of the story of how New Zealand and Australia separated around 40-80 million years ago and they'll now help scientists target future exploration of the sea floor to unlock the secrets of the Earth's crust," Arculus said, in the release.

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