Earthquake Swarm (11000+) El Hierro, Canary Islands

je55ie

lol I should have known you would be on it, thanks

maquiladora

jessie37 wrote: »

http://www.emsc-csem.org/Earthquake/earthquake.php?id=236815#

You still following this maquiladora? Any update for us? Thanks

The alert level traffic light system was raised from Green to Yellow two days ago due to some bigger quakes & ground deformation indicating magma movement.

We are getting closer to potential eruption but its hard to know how close. Days to years, take your pick. :pac:

je55ie

Any idea what effect an eruption would have there? and the scale?

maquiladora

jessie37 wrote: »

Any idea what effect an eruption would have there? and the scale?

Hard to know to be honest. There may have been an eruption there in 1793 but it is disputed. There is no real account of an eruption there in recorded history. So its hard to know if what is happening now is the build up to a small fissure eruption that won't cause any problems, or something else.

maquiladora

Total number of earthquakes since this swarm began is now over 8,000.

The population on the island will be getting new briefings tomorrow on the situation there.

maquiladora

Activity is really picking up today.

David Calvo, science presenter on on Canal 24 tweeted :

Situation worsens at El Hierro. 3,5 event widely felt, 5 events over 2,5 in the last 2 hours.

The 3.5 is the biggest earthquake so far. It's clearly seen here :

cherryghost

There was a few of similar magnitude over Katla last week, some people claiming eruption is imminent. We'll see. What was the advice given today from the CIG?

maquiladora

cherryghost wrote: »

There was a few of similar magnitude over Katla last week, some people claiming eruption is imminent. We'll see. What was the advice given today from the CIG?

Alert level is still at Yellow. All the earthquakes today have been below 10km it seems from this chart. I don't think an eruption is imminent unless we start seeing stronger quakes closer to the surface. Something is happening down there, but unless it looks like magma is on the rise upwards then I don't think they will change the alert level/advice.

maquiladora

This shows the accumulated energy released by the earthquakes since the start of the El Hierro swarm in July. You can see that there has been a steady increase all along until something changed in the past few days leading to a sharper rise and then today it has really increased.



There have been several 3+ earthquakes so far today, the biggest so far I think has been adjusted to 3.7. These bigger quakes are being felt at the surface but are still deep enough to indicate that an eruption of some kind is still not imminent.

I'll update the thread if anything more interesting happens.

maquiladora

About 300 people are being evacuated tonight from the Frontera region on the island due to the risk of a landslide due to the increased magnitude and size of the earthquakes today. Schools and road tunnels in that part of the island are also being closed now.

Original news in Spanish : http://www.elperiodicodearagon.com/noticias/sociedad/evacuan-a-300-personas-en-hierro-ante-riesgo-de-desprendimientos_703654.html

TheMilkyPirate

Christ, I've a holiday to gran canaria on the 11th of october, What are the chances of this affecting that??

Cakes.

It decides to get worse the week before I head to the Canaries....

Great! :P

cool webcam here for El Hierro area,

http://www.canarias360.com/panoramicas-de-el-hierro/volcanes-de-malpaso-el-hierro.html

Great Thread Maq. Good stuff great info.:D

thetonynator

Jake1 wrote: »

Great Thread Maq. Good stuff great info.:D

+1 to that, keeping us all very well informed, thanks!

Mountainsandh

Yes it's nice to have a thread on that, love reading this. Thanks.

up for anything

I still can't understand why people post volcano stuff in the Weather forum.

maquiladora

Jon Frimann the Iceland volcano blogger is also keeping an eye on this :

The magma is now on the way up in El Hierro. But the depth has now reached 10 km. But it depends on the rock and speed of the magma when it reaches the surface. But I am over 60% sure now that a eruption is going to start soon in El Hierro volcano.

Meanwhile, the IGN scientists think the chance of an eruption at the moment is about 15%.

fizzycyst

maquiladora wrote: »

Jon Frimann the Iceland volcano blogger is also keeping an eye on this :



Meanwhile, the IGN scientists think the chance of an eruption at the moment is about 15%.

Cheers for the updates Maq, would be cool if something interesting happens from all this, but we'll see I guess

up for anything

Eruptions blog has moved from Big Think to here:

Wired Science

up for anything

El Hierro Digital

The government evacuated 300 people tonight Border risk of landslides

Tuesday, September 27, 2011 20:51

Schools are closed in the municipality as a preventive measure

El Cabildo de El Hierro decides to close the tunnel from Los Roquille 23 hours until further notice

The Canary Islands government, given the risk of falls associated with volcanic seismic activity of El Hierro, and following the recommendations of scientists in the National Geographic Institute (IGN), which provides an increase in the intensity and frequency of seismic events from midnight will proceed to the preventive evacuation of some homes in the areas of Las Puntas, Sabin Pie Risco; Well Health and Guinea, in the town of Frontera.

The number of people estimated to displace School Residence Valverde and military barracks Anatolio Sources La Caleta, Will be approximately 300 people.

Also, the Cabildo de El Hierro will close the tunnel from Los Roquille at 11 tonight until further notice

As an additional measure the Ministry of Economy, Finance and Security has moved to the Ministry Education, Environment and Sustainability, the need to close schools in the municipality, if there were landslides affecting roads.

The Canary Islands government wants to send a message of peace and remind people that we are in yellow light, as was established on 23 September, and are not expected an imminent eruption.

The sequence of earthquakes may increase the frequency and intensity so that the citizens should also take into account the following recommendations:

If you are inside a building is important

Do not leave the building until the end of the movement.
Find shelter under strong structures.
Stay away from windows, windows, cabinets, walls and objects that can fall and get hit.
Not in the kitchen.
Do not use the elevator.
If the movement is strong, once completed, turn off electricity, water and gas.
In a public building (supermarket, cinema, library, etc):

Do not run terrified towards the exit.
Stay away from windows or glass doors.
Take cover under heavy structures.
With shelving space (libraries, archives, supermarkets, etc..) Exit corridors where the shelves and bend his knees, with the sides of the shelves.
At school, have the children kneel and students under his desk, putting a book on your head
If the shock is surprised abroad is convenient

Keep calm and have saved the others. Try to control any panic.
Go to an open area, once away from damaged buildings.
If there are damaged buildings, not between them
If car is traveling slowly stop the vehicle, do not block the road. Turn on the radio for the state authorities and recommendations for any particular roadblocks.

The authorities shall indicate the protective measures to be taken through the Media and Information Centers Centers Affiliation and Registration.
Try to answer calls for help and collaborate with the intervening, but not go to the affected areas without request to the authorities. Is important to avoid snooping by the disaster areas, that is also dangerous and difficult work of rehabilitation.

Accumulated Energy graph continues it's steep increase

Thanks to Andy Scollick at Eruptions from whose post I robbed the links.

maquiladora

For the past 2.5 hours or so the activity has calmed down a lot at El Hierro after almost constant earthquakes over the past couple of days. Almost like someone flicked a switch off!

Now we have to wait and see if this is just a pause or if it is the end of this phase of activity and not a build up to an eruption.

Almost all the earthquakes have still been below 10km so an imminent eruption is still not on the cards right now.

Edit. Looks like it was just a pause. Here we go again...

je55ie

maquiladora wrote: »

.

Almost all the earthquakes have still been below 10km so an imminent eruption is still not on the cards right now.

What depth signifies an eruption , is it just less then 10 and that means its definitely going to erupt?

maquiladora

jessie37 wrote: »

What depth signifies an eruption , is it just less then 10 and that means its definitely going to erupt?

Almost all the earthquakes so far are clustered between 10km and 15km. If you start seeing earthquakes getting more and more shallow then that indicates that magma is moving up to the surface, that would indicate a possible eruption.

Su Campu

Possibly evacuating a whole island! :eek: Has that ever happened before? Did they evacuate the whole of Monserrat that time in the 90s?

More on it here

maquiladora

Su Campu wrote: »

Possibly evacuating a whole island! :eek: Has that ever happened before? Did they evacuate the whole of Monserrat that time in the 90s?

More on it here

There is a plan to evacuate the island within 4 hours if the order is given. They would probably need to evaculate the whole island because, according to what IGN scientists have said in the local media there, they have no idea where an eruption would take place on the island. They expect that if there is an eruption, it will form a new volcanic cone somewhere.

maquiladora

A good summary on the eruptions blog :

http://www.wired.com/wiredscience/2011/09/increasing-indications-of-an-potential-eruption-at-el-hierro/

For El Hierro, the major hazard will be lava flows and potentially ash from the likely fissure vents that might open on the volcano – think about eruptions from Piton de La Fournaise or Kilauea as examples.

It has been a while, potentially almost 2,500 years since the last (and confirmed) known eruption at El Hierro, so this would clearly be the first since Europeans settled there. However, the signs right now still don’t suggest an eruption is inevitable, but rather magma is moving in the lower reaches of El Hierro’s magmatic system.

TheInquisitor

BORING!

maquiladora

TheInquisitor wrote: »

BORING!

Huh?

That chart is from July 23rd.

TheInquisitor

maquiladora wrote: »

Edit : This updates hourly

http://www.02.ign.es/ign/head/volcaSenalesAnterioresDia.do?nombreFichero=CHIE_2011-07-23&estacion=CHIE&Anio=2011&Mes=07&Dia=23#

My bad i thought it was from last hour!