Huge Prehistoric Sunken Islands Found in Indian Ocean

Scientists have discovered two huge sunken islands in the Indian Ocean, west of Australia.

The islands -- about the size of West Virginia or Scotland -- were once part of the supercontinent Gondwana and are almost a mile (1.6km) underwater.

Researchers from the University of Sydney, Macquarie University and the University of Tasmania said the islands were once above water and formed part of the last link between India and Australia.

The scientists made the discovery while mapping the seafloor of the Perth Abyssal Plain.

"The data collected on the voyage could significantly change our understanding of the way in which India, Australia and Antarctica broke off from Gondwana," University of Sydney geologist Dr. Joanne Whittaker said.

The islands, called "micro-continents," were formed when India began to move away from Australia, about 130 million years ago during the Cretaceous period, when dinosaurs roamed the Earth.

They became stranded thousands of miles (kilometers) from either coast as the land masses separated.

"The sunken islands charted during the expedition have flat tops, which indicates they were once at sea level before being gradually submerged," Whittaker said.

Read more about the ancient supercontinent Gondwana at Perth Now.