Biggest Volcanic Eruption In 100 Years Went Unnoticed 

6 months ago
The Harve volcano discovered in 2002 lies 600 miles off the New Zealand coast
It sits on the sea-bed one mile (1,600 metres) below the surface of the Pacific
The eruption happened in 2012 and the only evidence was a floating raft of rock 
Experts used submersibles to study and collect samples from the volcano
They found undersea deposits are not an accurate measure of eruption sizes

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