Canberra, Feb 2 : Scientists aboard the Southern Surveyor, a research vessel, have retrieved live and fossilized deep-ocean corals from a depth of 1,650 meters near the Tasman Fracture Zone, south-east of Tasmania, which might reveal ancient climate secrets.
The samples were collected by scientists from the US and CSIRO's (Commonwealth Scientific and Research Organization) Wealth from Oceans National Research Flagship.
The composition of deep-sea corals is used to determine past ocean conditions, such as temperature, salinity and the mixing of surface and deep-water layers, over tens to hundreds of thousands of years.
"These corals are evidence of an extinct coral reef," said the voyage's Chief Scientist, CSIRO Marine and Atmospheric Research's Dr Ron Thresher.
"Our sampling came up with some very old fossil corals of the type we are now seeing live and forming extensive reefs at depths of 800-1300 metres. This suggests that the reef extended much deeper in the past," he added.
The findings will provide ancient climate data that contribute to models of regional and global climate change, based on historical circulation patterns in the Southern Ocean.
According to Dr Thresher, over the coming year, the samples will be examined to determine when these newly discovered reefs existed and if their extinction can be related to long-term climate patterns.
The research team also captured images of life found on deep-sea pinnacles and valleys up to three kilometers beneath the Ocean's surface, by using a remotely operated submersible vehicle.