Scientists say they have identified an underwater continent two-thirds the size of Australia — and they are calling it Zealandia.

This newly proposed continent is about 1.74 million square miles in size and 94 percent submerged. But at its highest points, it protrudes above the ocean surface in the form of New Zealand and New Caledonia, according to a paper published in GSA Today, the journal of the Geological Society of America.

"If we could pull the plug on the oceans, it would be clear to everyone we have mountain chains and a big, high-standing continent above the ocean crust," Nick Mortimer, a geologist at GNS Science in Dunedin, New Zealand, told Reuters.

Zealandia is believed to have broken away from Australia about 80 million years ago and sunk beneath the sea as part of the break-up of the super-continent Gondwanaland.

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