World’s largest volcano discovered on ocean floor

TEXAS, United States, Friday September 20, 2013 – A team of geologists has discovered the planet’s biggest volcano, which is roughly the size of Britain and Ireland combined and is thought to be one of the largest volcanoes in the solar system.

“Tamu Massif” is part of the Shatsky Rise, a deep plateau on the floor of the Pacific Ocean located around 1,600 kilometres east of Japan.

According to the geologists, it comprises a single rounded dome in the shape of a shield, formed of hardened lava from an eruption around 144 million years ago; covers around 310,000 square kilometres, and peaks at a height of around 3.5 kilometres above the sea floor.

“Tamu Massif is the largest known single, central volcano in the world,” the team reported in Nature Geoscience.

Its area is “approximately the same as the British Isles or Olympus Mons on Mars, which is considered the largest volcano in the Solar System.

“Although Olympus Mons seems to be a giant because it is more than 20 kilometres in height, its volume is only around 25 percent larger,” the team said, adding that Olympus Mons has relatively shallow roots, while Tamu Massif delves some 30 kilometres into the earth’s crust.

Until recently, Tamu Massif was assumed to be a vast system of multiple volcanoes of a type that exists in about a dozen locations around the world. Its true status as a single massive volcano was only revealed when the geologists, led by William Sager at Texas A&M University, investigated further.

The team combined data from rock samples taken from an ocean-floor drilling project, with a chart of the seabed provided by deep-penetration seismic scanners. The resulting findings suggested that mega-volcanoes found in other parts of the solar system are not alone.

“The Earth variety is poorly understood because these monsters found a better place to hide – beneath the sea,” the paper says.

Tamu, which derives its name from Texas A&M University where Mr Sager taught before moving to the University of Houston, is thought to be extinct.

“The bottom line is that we think that Tamu Massif was built in a short (geologically speaking) time of one to several million years and it has been extinct since,” Sager said.

“One interesting angle is that there were lots of oceanic plateaus (that) erupted during the Cretaceous Period (145-65 million years ago) but we don’t see them since. Scientists would like to know why.”

Sager believes that other volcanic giants could be lurking among the dozen or so large oceanic plateaux around the world. Click here to receive free news bulletins via email from Caribbean360. (View sample)