8 Sep 2013

Sea off Japan hides volcano the size of Belgium

The world’s biggest volcano is discovered off the coast of Japan. But the underwater monster volcano last exploded in the Jurassic period, with only dinosaurs to watch it.

An active volcano, Kilauea in the Hawaii Volcanoes National Park

A volcano the size of Belgium has been discovered for the first time, underneath the Pacific ocean. Scientists exploring the vast Tamu Massif discovered that the immense rock formation was all made by one lava eruption.

It makes the new volcano not just the largest known volcano in the world, but the largest in the solar system – bigger than Olympus Mons volcano on Mars.

Located on a huge underwater plateau in the north-west Pacific Ocean to the east of Japan the 310,000 sq km (119,000 sq m) shield volcano is defunct, scientists say. Its last explosion was underwater and 142m years ago in the late Jurassic period, well before humans evolved.

The research published in Nature Geoscience suggests that more enormous underwater rock formations are likely to be the result of long dead colossal volcanos.