A team of researchers has discovered evidence of explosive volcanism 4km down on the Arctic Ocean seabed, challenging established notions of the nature of volcanic activity at great ocean depths.

The research team, led by scientists from the Woods Hole Oceanographic Institution, found jagged, glassy rock fragments spread out across a 10km² area around a series of small volcanic cones along the Gakkel Ridge, part of the spreading mid-ocean ridge system beneath the Arctic ice. ‘These are the first pyroclastic deposits we’ve ever found in such deep water, at oppressive pressures that inhibit the formation of steam, and many people thought this was not possible’, said Woods Hole geophysicist Rob Reves-Sohn.

A paper detailing the findings of the Arctic Gakkel Vents Expedition is published in the 26 June 2008 issue of Nature.

Information
Global Volcanism Program: East Gakkel Ridge volcanoes – summary information for the Gakkel Ridge volcanoes, excitingly dubbed ‘unnamed’ by the GVP

News
Under ice – Science News, 25 June 2008
Deep-sea volcanism on the Gakkel Ridge – Nature, 26 June 2008 (editor’s summary)
Geologists discover signs of volcanoes blowing their tops in the deep ocean – Innovations Report, 27 June 2008
Fire under the ice – EurekAlert, 27 June 2008