Undersea Volcano Near Canary Islands-Eruption Effects

El Hierro. Google Maps

El Hierro. Google Maps

Spain’s Instituto Geográfico Nacional (IGN) confirmed on Tuesday that an underwater eruption has occurred five kilomtres off the southern coastline of El Hierro, the smallest of the Canary Island. The eruption is Spain’s first since the eruption in 1971 of the Teneguía volcano on the island of La Palma (Canary Islands).

Scientists Monitor Underwater Volcano Eruption Near El Hierro

By MARK DUNPHY – Tue Oct 11, 2:53 p

The IGN says all three of its seismic stations on El Hierro in the Canary Islands have registered a volcanic tremor of low frequency in the south of the island at La Restinga (population 547), the southern-most village in the Canaries.  Residents of the town were summonsed to a local football field on Tuesday afternoon to be briefed on provisional evacuation procedures in the event of another eruption closer to the shore.

Scientists from IGN and CSIC (Consejo Superior de Investigaciones Científicas), meanwhile, have conducted a reconnaissance flight over the sea to the area south of the island, where they have located dead fish floating on the surface five kilometres from the coast. The dead fish were identified in an area where lower seismic magnitude occurred on October 9, at a depth of approximately 2 km.

The present volcanic activity is understood to be occurring at a depth of 600 metres (just under one kilometre) below sea level, in the Las Calmas sea.

Scientists from IGN, CSIC and the University of Cadiz have established their monitoring base at La Restinga. Efforts are underway to determine if the subsea volcanic vent is widening and if so, in which direction (away or toward El Hierro).

Initial reports of the eruption were received from crews on board four separate ships. Local media agency Canarias7 reported on Monday that Government authorities have suspended ferry activities to and from the 285 square-kilometre island.

English language newspaper  islandconnections.eu reported: “The martime chief for the province of Santa Cruz de Tenerife Antonio Padrón has issued a recomendation that boats should not sail closer than four miles off El Hierro. Divers have also been told to suspend all activities.

 

 

 

El Hierro (highlighted) on Google Earth

El Hierro (highlighted) on Google Earth

The eruption takes place amidst an unprecedented earthquake swarm in El Hierro. The number of earthquakes recorded since July 17, 2011 on El Hierro has now exceeded 10,000.

Hierro, a shield volcano, has had a single historic eruption from the Volcan de Lomo Negro vent in 1793. The eruption lasted approximately one month and produced lava flows.

The recent surge in the number and intensity of earthquakes prompted officials from the IGN and The Canary Islands Government to raise the alert level for the Hierro volcano to ‘Yellow’ late last month. The alert remained in place on Monday, but the estimated 11,000 residents of El Hierro were being reassured not to be alarmed.

The majority of the earthquake activity shifted from El Golfo in the island’s northwest to beneath the Las Calmas Sea in the south earlier this month. Surface deformations exceeding 35mm have also been recorded on the island in recent weeks.

Evacuations

A dramatic rise in recorded earthquakes on El Hierro prompted officials to evacuate some local residents, shut El Hierro’s main tunnel, and close local schools on 27 September.

The Spanish Civil Guard (Guardia Civil) advised almost 50 residents of the municipality of La Frontera to leave their homes because of landslide fears. Two units of the Spanish military’s emergency intervention unit (EMU) were also placed on standby to depart the nearby island of Tenerife to assist in the possible evacuation of hundreds of other El Hierro residents.

Meanwhile, the island’s main tunnel (Tunel del Golfo), which links Frontera to Valverde, was shut forcing motorists to travel across the 280-sq-km island via a mountain road. The Cabildo de El Hierro also ordered the closure of schools.

to read more, see the graphs and the videos, go to:    http://www.irishweatheronline.com/news/earth-science/geology/scientists-monitor-underwater-volcano-eruption-near-el-hierro/41346.html

Volcanic Activity on Canary Islands prompts Evacuations

Rising Volcanic Activity Prompts Evacuations On El Hierro, The Canary Islands

By MARK DUNPHY – Wed Sep 28, 4:45 pm

 

MODIS satellite image of The Canary Islands on Tuesday 27 September 2011

MODIS satellite image of The Canary Islands on Tuesday 27 September 2011

Fears are growing that the El Hierro volcano in The Canary Islands could soon erupt after seismic activity beneath the island increased dramatically during Tuesday and Wednesday.

Over 150 earthquakes were recorded on the smallest of the Canary Islands during Tuesday prompting officials to evacuate some local residents, shut El Hierro’s main tunnel, and close local schools.

At least 20 earthquakes, exceeding magnitude 3.0 on the Richter Scale, have been felt by local residents during the last 24 hours. The most recent earthquake, which measured 3.4 magnitude, was recorded just off the southern tip of the island at 07:04 am Wednesday.

The rise in seismic activity last night prompted the Spanish Civil Guard (Guardia Civil) to advise almost 50 residents of the municipality of La Frontera to leave their homes because of landslide fears.

Plans are also underway to evacuate more of the island’s 10,000 residents, according to Canarias7.es. The newspaper reported that two units of the Spanish military’s emergency intervention unit (EMU) will depart nearby island Tenerife this afternoon to assist in the possible evacuation of hundreds of El Hierro residents.

Meanwhile, the island’s main tunnel (Tunel del Golfo), which links Frontera to Valverde, has been shut forcing motorists to travel across the 280-sq-km island via a mountain road. The Cabildo de El Hierro also has ordered the closure of schools on Wednesday.

Hierro, a shield volcano, has had a single historic eruption from the Volcan de Lomo Negro vent in 1793. The eruption lasted approximately one month and produced lava flows.

The Canary Islands Government commenced an in-depth geological survey of El Hierro earlier this month in an effort to determine the source of an earthquake swarm. The Government raised the volcanic risk level to ‘Yellow’ on Sunday, the highest alert status since an unprecedented earthquake swarm commenced in mid-July.

The unprecedented seismic activity commenced on 19 July (the activity was first reported by iWeather Online on 26 July). In excess of 8,200 earthquakes have been recorded up to Wednesday, 28 September 2011.

Up to last weekend, the majority of earth tremors ranged between 1 and 3 magnitude. However, the majority of quakes are now registering between 2 and 4 magnitude and are occuring at depth of 14-17 kilometres, according to the National Geographic Institute (IGN).

Speaking to the El Pais newspaper, volcanologist Juan Carlos Carracedo suggested that an eruption on El Hierro would “not be a major surprise”. He explained: “It is the youngest of the Canary Islands. There is a ball of magma which is rising to the surface and it is stationed at the limit of the earth’s crust. At the moment we do not know if that ball of magna will break the crust and cause an eruption.”

IGN Director, María José Blanco said that any eruption on El Hierro would most likely have a “low explosion value”. He added that an imminent eruption is unlikely.

In the meantime, the frequent and increasingly intense earthquakes being felt throughout El Hierro are unlikely to appease the residents of and visitors to the tiny island.

for more, go to:    http://www.irishweatheronline.com/news/earth-science/geology/rising-volcanic-activity-prompts-evacuations-on-el-hierro-the-canary-islands/39807.html/comment-page-1

Gulf of Mexico Evacuations

Oil firms start U.S. Gulf evacuations due to weather

ReutersBy Kristen Hays and Erwin Seba | Reuters – Wed, Aug 31, 2011

  • HOUSTON (Reuters) – BP Plc on Wednesday became the first major oil producer to say it was evacuating some workers from Gulf of Mexico oil and gas platforms because of a tropical disturbance that could become a named storm this week.

Later on Wednesday, Anadarko Petroleum Corp joined BP saying it has evacuated non-essential workers from three platforms in the Gulf.

Royal Dutch Shell also was preparing to evacuate some workers and expected to decide whether to move forward with that during the day, spokeswoman Kelly op de Weegh said.

Shell was monitoring the system over the northwestern Caribbean Sea and the eastern Gulf. The National Hurricane Center said the weather formation had a 30 percent chance of becoming a cyclone in the next two days.

Chevron Corp, Exxon Mobil Corp, ConocoPhillips and Apache Corp also said they were monitoring the system.

BP, the biggest oil producer in the Gulf with eight company-operated oil and gas platforms, said it was evacuating from five platforms more than 500 “nonessential” workers, or those not directly involved in production, such as cooks.

The platforms involved are Thunder Horse, the world’s largest with capacity to produce up to 250,000 barrels of oil per day, and Na Kika, Mad Dog, Holstein and Atlantis.

“Essential personnel remain on board to continue safe operations and prepare the platforms for potential shut-in and full evacuation in the event it becomes necessary,” the company said in a statement.

Anadarko said the workers were taken from the Gunnison, Nansen and Boomvang platforms.

“We will continue to monitor the path of the weather and are prepared to evacuate all personnel and shut in production if necessary,” Anadarko said in a statement.

Shell is the second-largest producer in the Gulf, operating six oil and gas platforms.

Mexico’s state oil monopoly Pemex said it was monitoring the weather but not yet taking any emergency or precautionary steps.

The U.S. National Hurricane Center gives the disturbance, which would be called Lee if it becomes a tropical storm, a 60 percent chance of becoming a tropical cyclone in the next 48 hours, but said it could develop further when it reaches the western Gulf.

for more, go to:   http://news.yahoo.com/oil-firms-start-u-gulf-evacuations-due-weather-005732473.html