Underwater Lava: Eruptions Could Create New Island in the Canaries

It could eventually rise from the sea to create a new part of the archipelago.

ByABC News
October 27, 2011, 3:00 PM

Oct. 30, 2011— -- What would the island be called? And who would own it? Spewing magma and growing in height, an underwater volcano off the Canary Island of El Hierro has captured the imagination of locals in recent weeks. It could eventually rise from the sea to create a new part of the archipelago.

It hasn't yet reached the surface, but residents of the Canary Islands have taken to the internet to suggest names for a potential new islet. There are already more than 500 suggestions. Favorites include "The Discovery," "Atlantis" and "The Best." Meanwhile Spanish newspapers are taking a different approach to the subject, debating who would take responsibility for the new territory.

It's an underwater volcano off the coast of El Hierro, the southern-most Canary Island, which has caught the imagination of locals. For three weeks it has been spewing magma into the sea in the first volcanic eruptions on the Canary Islands for 40 years. The lava is already towering 100 meters above the seabed -- another 150 meters and it will protrude above the Atlantic Ocean, creating a new island. For Canarians, it's a welcome new attraction.

Whether the eruption near the archipelago off the northwest coast of Africa will ever actually result in new land remains uncertain. But it's clear that the magma reservoir under El Hierro is simmering unchecked, constantly pouring out magma and causing the ground to shake several times a day. Since July, there have been more than 10,000 earthquakes -- mostly imperceptible -- on El Hierro. Volcanologists expect more eruptions, but they don't know where the lava will be released. Even small eruptions on land are possible. The volcanic activity will "probably last for some time," said the Mayor of El Hierro, Alpidio Armas.Dead Fish

The effects of the underwater volcanic events are clearly visible: powerful eddies result from explosions in the deep. A sea of ash bigger than El Hierro itself is floating off the island, with gas bubbling up and dead fish scattered in the water.

Politicians and scientists are offering daily advice on possible risks to the local population, but their understanding of events under the seabed is far from complete. "Recent volcanism in the Canary Islands is not well known," says a report in the "Natural Hazards and Earth System Sciences" journal by researchers at the Spanish National Research Council (CSIC) in Barcelona, led by Rosa Sobradelo. Nonetheless, advice on the potential dangers is being dispensed by the authorities on El Hierro as well as in the rest of the Canary Islands.

Scientists have stepped up their monitoring; there is even a submarine taking pictures of the ocean floor, showing the new undersea mountain, already 700 meters (2,300 feet) wide. A 150-meter (490-foot) crater can also be seen. There is also fissure three kilometers (two miles) long that is clearly gushing magma.Disturbing Measurements RecordedTo the south of El Hierro, the earthquakes suggest persistent outbursts of lava, according to the ITER research institute on Tenerife. They show a pattern that is typical for flowing liquid, a so-called harmonic volcanic tremor. Presumably, there are constant small eruptions on the ocean floor. But the lava usually clogs the fissure quickly after such eruptions, forcing further magma to seek new channels -- exactly what seems to be happening now.