Worlds Largest Volcano Discovered Under the Pacific Ocean

Confirming the old saying that we know more about other planets than what is happening on the ocean floor, geologists announced this week that Earth's largest volcano is under the Pacific, to the east of Japan.
Don't get me wrong, these guys didn't just stumble upon a huge active volcano while on an underwater stroll. The area known as Tamu Massif was previously thought to have been a series of volcanoes, just like Hawaii and Iceland,  instead of what has turned out to be one significantly large volcano. Oh and don't worry about activity. The area was formed 145 million years ago and went extinct quite soon after. So while plesiosaurs would have been freaked out by it, there is no need for you to be.

William Sager of the University of Houston headed this 15 year study which composed of a large series of sonar mapping and drill cores concluded that all flows in the area originated from one source and not several as a series of volcanoes would present. Sager states: "Before this we weren't sure that we had single volcanoes that could grow to this size. Now we do."

The world’s biggest active shield volcano, Mauna Loa on Hawaii, has an areal footprint just 15% of Tamu’s — but Mauna Loa is taller, rising 9 kilometres from sea floor to summit.

The knowledge that volcanoes this large can and have formed on Earth previously has led researchers to rethink and reassess whether other presumed series of extinct volcanoes may actually be large singular volcanoes as well.  Sager believes another candidate may be the Ontong Java plateau east of the Solomon Islands, which has similar features to the Tamu Massif. "It's being investigated by Japanese researchers," he says, "so the Tamu Massif might not be the last word."