Scientists have discovered a massive coral tower on Queensland's Great Barrier Reef that's taller than the Empire State Building.
The 500 metre high undersea skyscraper-like pillar of reef was found just off Cape York during a seabed mapping project last week.
The tip of the soaring coral plinth sits 40 metres below the ocean's surface and it has a base that's about 1.5 kilometres wide.
Schmidt Ocean Institute researchers discovered the giant section of reef during a 12-month exploration of the ocean surrounding Australia.
Biologist Tom Bridge says it is the first detached reef found in more than 120 years, with the other seven mapped in the late 1800s.
"This newly discovered detached reef adds to the seven other tall detached reefs in the area," he said on Wednesday.
The collection includes the reef at Raine Island, near Cairns, which is the world's most important green sea turtle nesting area.
The team aboard the research vessel Falkor has also found five undescribed species of black coral and sponges during their expedition.
They also spotted Australia's first sighting of a rare scorpionfish in the Coral Sea and Great Barrier Reef Marine Parks.
The scientists also discovered the longest recorded sea creature in Ningaloo Canyon off Western Australia's northwest coast - a 45 metre Siphonophore, which is a gelatinous carnivore that lives deep in the ocean.
Further south they found deep-sea coral gardens and graveyards in Bremer Canyon Marine Park, off WA's southern coast.
"We know more about the surface of the moon than we know about what lies in the depths beyond our coastlines," Dr Bridge said.
Australian Associated Press