Researchers have found that the world’s largest deep ocean volcanic eruption happened in New Zealand. Named as Havre, the deep ocean volcanic eruption was first discovered in 2002. A solidified volcanic rock known as pumice raft – 400 square kilometres in size – found floating in the ocean near New Zealand in 2012 showed that underwater eruption had occurred.
The eruption involved 14 aligned vents causing a ‘massive rupture’. “When this rock was produced by the volcano, it rose through the water column onto the sea surfaced and then it was dispersed by wind and sea currents,” lead author Rebecca Carey, volcanologist at the University of Tasmania, was quoted as telling Xinhua.
“We knew it was a large scale eruption, approximately equivalent to the biggest eruption we’ve seen on land in the 20th Century,” Carey added. For the study, the team successfully mapped the remote location with submersible vehicles including a remotely operated vehicle and an automated underwater vehicle to make high resolution topographic maps of the sea floor.
They did about 12 different surveys for 8-12 hours each and those maps are so high resolution that were then able to use a remotely operated vehicle which is tethered to the ship, to actually go down and make observation of the eruption and also bring back samples. With more than 80 per cent of the world’s volcanoes located underwater, scientists like Carey believe it’s vital to learn more about them.
“Volcanoes provide heat and chemicals to the ocean and that input is actually really important when it comes to sustaining life,” Carey said. “Havre is a cornerstone eruptive event because for the first time we are able to constrain exactly what happened, where it happened, at what depth, how much and how fast it erupted.”
“With this sort of quantitative understanding, we are able to probe the fundamental questions about how submarine volcanoes work,” Carey noted.