by Tom Worden
29 September 2011

from DailyMail Website

Spanish version

 


108 square mile island is home to 10,000 people
More than 8,000 tremors have been recorded on island in the last two months
Last eruption on El Hierro was in 1793 and lasted a month
Residents put on standby for emergency evacuation over fears of landslides
 

 

A holiday island popular with Britons is preparing for a mass evacuation because of a possible volcanic eruption.

Experts have recorded 150 tremors on El Hierro, the smallest of the Canary Islands, since yesterday - raising fears of an imminent eruption. Last night 53 people were ordered out of their homes over fears of landslides and the army has been called in to prepare for a possible evacuation.

 

About to blow?

Parts of the Canary Island of El Hierro have been evacuated over fears of a volcanic eruption
 

Schools on the tiny island, home to 10,000 people, have been closed and a tunnel linking the two main towns - Frontera and Valverde - has been shut.

Volcano expert Juan Carlos Carrecedo said:

"There is a ball of magma rising to the surface producing a series of ruptures which generate seismic activity. We don't know if that ball of magma will break through the crust and cause an eruption. But he warned an eruption was possible 'in days, weeks or months'."

The last volcanic eruption in the Canary Islands took place on the island of La Palma in 1971.

 

Tectonic plates map with the Canary Islands circled.

The last volcanic eruption in the Canary Islands took place on the island of La Palma in 1971
 

Readings: A seismologist records the seismic activity on the island.

There are fears the tremors could cause landslides
 

El Hierro, which has an area of just 108 square miles, is popular with British tourists looking for quiet sunshine holidays away from the bustle of neighbouring islands like Tenerife and Lanzarote.

It is not known how many, if any, Britons are currently on the island.

More than 8,000 tremors have been registered on El Hierro since July 19, collectively known as an earthquake 'swarm'. Only 15 of them have been strong enough for people on the island to notice, but yesterday an earthquake of 3.8 on the Richter scale was felt all over the island.

The last eruption on El Hierro, which has around 250 small volcanic craters, was in 1793 and lasted for a month.

Newspaper Canarias7.es reported that two units of the Spanish military's emergency intervention unit will leave Tenerife today to help with any evacuation operation.

 

Eruption: A diagram showing where the epicentres of tremors have been.

El Hierro was formed when three volcanoes erupted 100 million years ago


Warning: Seismic activity is shown on a monitoring screen.

Experts say a ball of magma is rising up underneath El Hierro, and could trigger a volcanic eruption
 

The Canary Island government began a geological survey of El Hierro earlier this month to determine what was causing the tremors.

It raised the volcanic risk to 'yellow' on Sunday - the highest alert status since the earthquake 'swarm' began in July. Some experts said a volcanic explosion could actually attract more tourists to the island.

Eumenio Ancochea, volcanologist at Madrid's Complutense University, said:

'An eruption could fill the island with people interested in these phenomenon. It's normal that people are scared but there is no danger. After an eruption the lava advances at a few meters per hour and you can easily take photographs as it descends.'


SO IS EL HIERRO ABOUT TO EXPLODE?

Magma: El Hierro is the smallest of the Canary Islands,

but has more than 250 small volcanic craters
 

Under the Canary Islands lies an area of magma which is able to break through to the surface when the African Plate - on which the islands sit - shifts. It is to this that the islands owe their very existence.

Most of the islands are still volcanically active and there has been speculation that a smaller, previously undetected fault line also runs through the chain.

El Hierro - which means 'iron' in Spanish - was formed after three volcanic eruptions 100 million years ago and is topped by a volcano more than 6,000ft high. Volcanic activity - mainly where three ridge lines converge - has caused El Hierro to expand continually. The last time it erupted was in 1793.

Some 50,000 years ago, massive landslides triggered by earthquakes caused a large part of the island to crack off and fall into the Atlantic Ocean, according to Irish Weather Online. That created the El Golfo valley on the island and caused an 300ft-high tsunami that probably reached the American coast.

This feeds into the belief that volcanic activity on La Palma - the most tectonically active of the Canary Islands - could trigger a mega-tsunami. The theory - which has never been confirmed - claims that a possible fault line through the island would cause a major landslide under certain circumstances.

That landslide would then spark a tsunami that would cause extensive damage all down,

  • the Atlantic Coast of the U.S.

  • the Caribbean

  • Western Europe

  • West Africa

  • the east coast of South America