Wednesday, November 9, 2011

Volcano Producing a New Island?

From Accuweather.com:

A volcanic eruption under shallow water in the Canary Islands may mark the birthing pangs of a new island.

The outpouring of lava onto the seafloor has been happening about 5 km (3 mi) off southern El Hierro island, at a depth of at least 50 to 100 meters (approximately 150 to 300 feet), according to various reports.

Speculation on the part of volcanologists has been that, were it to last long enough, the eruption will eventually reach the sea surface, even beginning the building of a new island.

If such an event were to happen, the eruption would undergo significant changes in character, including potentially violent eruptions. This possibility was likely behind a government decision to evacuate the town of La Restinga, which was reported on Nov. 5 by Canarias7.es.

When the depth of water above an undersea volcanic erupt becomes shallow enough, violent steam eruptions often take place. This phase of undersea eruption is known as the "Surtseyan" phase, after the Icelandic island of Surtsey, which rose from the Atlantic Ocean in such a way during 1967.

Still more growth of such an island would eventually culminate in lava emerging above the tide, potentially arming the newborn island against the battering of wind and wave.

Molten rock has been emerging on the seafloor off the island of El Hierro since at least the first half of October. Evidence for the otherwise hidden eruption has included churning and discoloration of the sea, as well as fresh, hot volcanic rocks floating above the eruption site.

After peaking in late October, the eruption of lava waned, only to begin with renewed vigor after the start of November.
Swarms of mostly small earthquakes, which began before the eruption, have been ongoing.
El Hierro and the Canaries as a whole are of volcanic origin; some volcanoes on the Canaries, including El Hierro, have erupted in historic times.



No comments:

Post a Comment