50 million year old volcano cluster near Sydney

Australia’s new ocean-going research vessel Investigator has discovered extinct volcanoes likely to be 50 million years old, about 250 km off the coast of Sydney in 4,900 m of water. While scientists were searching for the nursery grounds for larval lobsters, the ship was also routinely mapping the seafloor when the volcanoes were discovered. They haven’t been found before now, because the sonar on the previous Marine National Facility (MNF) research vessel, Southern Surveyor, could only map the sea floor t