March 25, 2015
Undersea Perth Canyon explored for first time
Off the coast of Western Australia is Perth Canyon, a massive geographical formation the size of the Grand Canyon. Perth Canyon sits far under the surface of the Pacific and it hadn’t been thoroughly explored until this month.An international team of researchers from embarked on a two-week expedition on March 1 and came back with a treasure trove of maps, observations and other data.
Aboard the research vessel Falkor, the explorers used cutting-edge mapping systems and a remotely operated vehicle (ROV) that could dive the nearly 2200 yards to analyze the canyon. Malcolm McCulloch, head of the expedition, said the team had travelled over 1,100 miles to be able to map the more than 150 square miles of the canyon and had documented its maximum depth at over 14,000 feet.
"We have discovered near pristine sheer drop cliffs of over 600 meters (2000 feet) and mapped structures that are rarely found in other parts of the ocean," McCulloch said. “It is truly a huge canyon which has cliff faces and outcrops similar to the Grand Canyon but now submerged beneath the ocean and extending to depth of more than 4 kilometers (2.5 miles). It is at a depth where light can’t penetrate, making a dark water column where there are no signs of light from above or below.”
A whole new world
In the canyon, McCulloch’s team uncovered an astonishing deep-sea community of corals and other organisms that survives in darkness and sticks to the hard stone of the canyon’s walls at about a mile under the ocean surface. Venus flytrap anemones, golden coral and other organisms have only been occasionally encountered before in this part of the Pacific. However, these creatures have been spotted in other areas of the world’s deep oceans.
The team said they plan to evaluate corals from the canyon to determine their age, how quickly they expand and if the conditions in the water column may have shifted as a result of effects of global warming or ocean acidification. Studying the samples compiled by the ROV means the team will better comprehend the deep-sea history of these creatures and their future ability to deal with the demands of climate change.
The team also made another unexpected discovery – a long-lost autonomous glider that had been used in past research. The glider was found resting at the bottom of the canyon, about a half mile below the surface.