El Hierro Volcano eruption (Canary Islands) : Part 2 - September 25 until October 10, 2011

This is Part 2 of the  El Hierro Volcano eruption report


Our tweets are also posted into our Facebook Volcano Page
With the collaboration of Joke Volta, an El Hierro resident.

Read also: Scientific paper reveals massive historic Tenerife volcano flank collapse
Read also: Economic impact on El Hierro and the Canary Islands if an aerial eruption would occur

Read also: Part 1 (from July 28 until early September)
Read also: Part 2 (from September 25 until October 10 )
Read also: Part 3 (from October 11 until October 13 )
Read also: Part 4 (from October 14 until October 17 )
Read also: Part 5 (from October 18 until October 21 )
Read also: Part 6 (from October 22 until October 26 )
Read also: Part 7 (from October 27 until October 31 )
Read also: Part 8 (from November 1 until November 3
Read also: Part 9 (from November 4 until November 6
Read also: Part 10 (from November 7 until November 8)
Read also: Part 11 (from November 9 until November 11)
Read also: Part 12 (from November 12 until November 15)
Read also: Part 13 (from November 16 until November 19)
Read also: Part 14 (from November 20 until November 23)
Read also: Part 15 (from November 24 until November 27)

Parador de El Hierro, gives a good idea on the coastline - Click on the picture to watch a video

Update 10/10 - 21:31 UTC : Fishing vessels have been ordered not to throw their nets in the expected eruption area. As far as now, no gases or bubbles have been detected in the area which is supposed to be the eruption area. This does not necessarily mean that there is no eruption, but that the depth of the magma vent is at least several hundred meters below sea level.
In the meantime, the harmonic tremors are unchanged (see link below).
Emergencia El Hierro has not published a new report tonight.

Update 10/10 - 17:01 UTC : Ramon Ortiz, a vulcanologist specialized in Canary Island volcanoes and currently advising the authorities, says in ElMundo that today's eruption will be probably at a depth greater than 600 meter below sea level and about 5 km to the southeast of El Hierro.
Ortiz also said that the the Harmonic Tremors which started this morning showed that the eruption had started. They were reported in this site only hours after they started (see link and description below).
The latest eruption on the Canary Islands took place on La Palma Island in 1971 (see the video below from this eruption).

IMPORTANT UPDATE 14:31 UTC : PEVOLCA has just published a Press Statement that it is still unsure that an eruption is going on in the Las Calmas Sea. Scientists of IGN which make part of the PEVOLCA committee have stated that IGN has recorded the emission of volcanic gases at the south side of the island. The committee stresses that the gases are NOT dangerous for the population.
Additionally IGN reported that the emission might also be an eruptive phase but at the present time there is no 100% proof for it. A certainty however, IGN reported, is that "purely volcanic harmonic tremors" have started.
At 7 PM (19:00) local time later today, a new report will be published with the latest results and conclusions of the scientists.

The full report in Spanish :

La Dirección del PEVOLCA afirma que no hay certeza de una erupción volcánica submarina en la Isla de El Hierro.
El IGN ha constatado durante la pasada madrugada una pequeña liberación de fluidos y gases de tipo volcánico que no suponen riesgo para la población.
El Instituto Geográfico Nacional (IGN), órgano oficial para la vigilancia volcánica, ha confirmado esta mañana a la dirección del Plan de Protección Civil por Riesgo Volcánico (PEVOLCA), que aunque no hay certeza de que en estos momentos se esté produciendo una erupción volcánica submarina, desde la pasada madrugada se ha registrado una liberación de fluidos y gases de tipo volcánico en la costa sur de la Isla.
Los científicos del IGN han comunicado a la dirección del Plan que todos los indicadores que han analizado apuntan hacia la posibilidad del inicio de un proceso eruptivo ya que ha cambiado el tipo de onda que han registrado los sismógrafos en las últimas horas, lo que implica el inicio de emisión de gases o lava al exterior.
En este sentido, se trata de señales puramente volcánicas que no se habían observado hasta ahora aunque habría que confirmar esta tendencia con otros parámetros como la presión, liberación de gases o la deformación del terreno, entre otros.
El helicóptero del Grupo de Emergencias y Salvamento del Gobierno de Canarias (GES) ha realizado vuelos de reconocimiento durante la mañana de hoy sin observar salida de material volcánico a la superficie.
Aunque esta actividad no supone riesgo para la población, la Dirección del PEVOLCA recomienda a la población que realice sus tareas habituales con normalidad y que permanezca atento a cualquier actividad inusual.
Al término de la reunión mantenida esta mañana en Valverde se determinó que esta tarde, a partir de las 19 horas, la Dirección del Plan informará de los últimos análisis que realicen los científicos del IGN.

IMPORTANT UPDATE 13:13 UTC : The local council of El Hierro has confirmed that a submarine eruption is going on, but stressed that there is NO present danger for the El Hierro population. Following Alpidio Armas, the Cabildo de El Hierro, the eruption occurs at 5 km to the south of La Restinga. Armas also said that the news is "very good" as the accumulated energy will decrease by the present eruption. Armas also said that visitors are invited to visit the island as the island itself is not dangerous ... (ER: this is a very optimistic statement)

Update 10/10 - 11:59 UTC : A group of scientists equipped with special cameras is currently flying over the Las Calmas see to check whether the eruption did happen. As stated in the Important Update below, the news of the eruption comes from 4 ships and is not official as yet.

IMPORTANT UPDATE : Following the Spanish Newspaper El Mundo, a small submarine eruption has taken place 7 km out of the coast. The eruption occurred at 1200 meter below sea level. The eruption took place in the Las Calmas sea to the south of the island at 10.43 local time (09:43 UTC). We expect an official statement soon.
The news comes from 4 boats presently navigating in the Las Calmas sea. Authorities have suspended the ferry activities to and from the island following Canarias7, a Canary Island newspaper.
This eruption news still has to be confirmed by IGN
What a pity that the submarine robots which were used in Greece and at the Oregon coast have are not used here. These submarine robots are showing live HD footage from underseas activity. Fly them over and use them, a unique opportunity to follow an submarine eruption.
Click here for the El Mundo article (in Spanish)

Update 10/10 - 09:31 UTC : As we have expected earlier, the PEVOLCA committee will meet today at El Hierro to discuss the present seismic activity.

Seismogram 10/10/2011 - Click to open - courtesy IGN

Update 10/10 - 09:04 UTC : We expect an informative report of the local science / authorities committee later today as the tremor activity below El Hierro has changed considerably.
For those among you interested in the seismograms, please take a look at the activity change of the tremors or click on the thumbnail.
Erik Klemetti, the assistant professor of geosciences at Denison University wrote an in-depth explaining article on "Harmonic Tremors" on October 2010 (not for the El Hierro volcano). What people reading this article certainly have to know is that :
Harmonic tremors are the type of seismicity that most people associate with an impending or ongoing volcanic eruption – that is, magma movement generates the seismicity. The tremor might precede an eruption by days or hours or they might not lead to an eruption at all.
The full article can be viewed here

Update 10/10 - 07:43 UTC : Less than an hour ago, Geolurking, a nickname for a dedicated volcano follower, has published a very interesting 3-D plot he made of the tremors so far beneath El Hierro. The video shows the depth of the hypocenters and the magnitude (colors).
The text below the video : El Hierro may be experiencing harmonic tremor at this moment.
What is an harmonic tremor ? : A harmonic tremor is a sustained release of seismic and/or infrasonic energy typically associated with the underground movement of magma and/or venting of volcanic gases from magma. (Wikipedia description)

El Hierro volcanic earthquakes epicenter map - courtesy IGN

Update 09/10 - 21:53 UTC : Since 03:08, no new shallow quakes have been recorded. The depth of the 15 earthquakes since then varied from 11.6 km to 18.7 km. The strongest earthquake today was a 3.6 magnitude which was felt by the people living on El Hierro. Earthquake -Report.com congratulates the Spanish IGN (National Geographic Institute) and the Canary Island authorities for their very informative updates and real time data.

Update 09/10 - 16:43 UTC : The remarkable number of shallow earthquakes has stopped at 03:08 UTC this morning. Since then only earthquakes at the normal depth of 10 to 15 km have been reported. A total of 10 extremely shallow earthquakes have been noticed in between 00:24 and 03:08, the shallowest at 500 meter beneath the surface.
M 1.5 2011/10/09 03:08:19 epicenter 0.50 km
M 1.5 2011/10/09 03:08:47 epicenter 0.90 km
Both quakes occurred with a difference of 28 seconds

Update 09/10 - 13:15 UTC :
Since the strongest quake we have been reporting on (just before midnight), a number of very different events have taken place. If you look carefully at the list below we noticed a serious decrease in number of events, but some quakes were measured at the shallowest depth so far.
Earthquakes of magnitude 1.5 or greater as reported today by IGN
Date Time Depth Magnitude
09/10/2011 07:14:07 13 2.7 SW EL PINAR.IHI
09/10/2011 04:10:13 15 2.3 SW EL PINAR.IHI
09/10/2011 03:08:19 1 1.5 S EL PINAR.IHI
09/10/2011 03:06:21 3 1.5 S EL PINAR.IHI
09/10/2011 02:02:19 14 1.9 SW EL PINAR.IHI
09/10/2011 01:28:22 16 1.7 SW EL PINAR.IHI
09/10/2011 00:32:59 3 1.7 S EL PINAR.IHI
09/10/2011 00:26:56 15 1.7 SW EL PINAR.IHI
09/10/2011 00:24:29 2 1.5 S EL PINAR.IHI

Epicenter 4.3 earthquake - image courtesy ING

Update 08/10 - 22:15 UTC : Tonight at 20:34 UTC, the strongest earthquake so far has occurred below El Hierro at a depth of 10 km (data EMSC). The earthquake had a magnitude of 4.3!
IGN data
2011/10/08 20:34:48.28 depth 12.5 km Magnitude 4.30
Click here for the exact location of the epicenter (green arrow)
Following IGN , the epicenter was approx. 600 meter out of the coast.
Following IGN the earthquake was felt as an intensity MMI III earthquake (weak shaking).
Earthquake-Report.com is convinced that the return of the evacuated people to their villages might be postponed for some time after this moderate volcanic earthquake. The evacuation took place after the authorities had to act because of landslide risk which could have been triggered by the quakes.
At the other hand the number of earthquakes of M 2 or higher has decreased substantially today as their were only 4 since the last 20 hours.

Update 07/10 - 23:30 UTC : The 2 strongest earthquakes today had a magnitude of 3.7 and 3.8 at a hypocenter depth in between 12 and 16 km. They occurred at 11:27 and 22:29 UTC. Normally this kind of earthquakes are felt by humans.

EMSC - Bing image - Red : last 24 hours

Update 07/10 - 17:15 UTC : The situation is unchanged at the moment. The tunnel remains closed until the engineers have finished their inspection. The earthquakes are very similar than those in the beginning of the week. The number of earthquakes (18 = or > than M2 on October 6 and 12 the first 17 hours of October 7) and the magnitude (strongest today 3.6 and yesterday 3.2). Depth always between 10 and 15 km, which shows clearly that the magma is not getting closer to the surface.

Update 06/10 - 09:36 UTC : IGN and the local authorities have decided in a meeting this morning to maintain the closure of the Los Roquillos tunnel until a geotechnical examination report has been delivered. The authorities will decide on a reopening after analyzing this report.

Update 06/10 - 07:31 UTC : The strong M+2 volcanic earthquake activity has subsided. Yesterday October 5, only 4 such quakes were recorded. The first 7 hours of October 6, 2 quakes respectively 3.2 and 2.8 have occurred at a depth of 12 km.

Update 05/10 - 20:00 UTC : During a meeting of the Canary Islands government with the Spanish government (Civil Defense) in Madrid earlier this morning was decided that the present "Yellow Alert" status will be maintained.
The meeting also decided that the local government should meet with the scientists of the seismological and volcano agency ING one of the coming days to discuss the risk on landslides, which could be triggered by the seismic activity (the reason for the evacuation).
The evacuated people are eager to return to their houses but the local government and authorities have informed them that the landslide risk is still too high. Yesterday 2 tremors were felt by the locals. The seismic activity goes up and down. Today only 2 tremors have exceeded magnitude 2 (13 hours time). Yesterday, in 24 hours we counted 11 tremors M 2 or more. On October 3 : 34 and on October 2 : 26.
Additionally the tremors, as said earlier, are moving to the south.
(Our) conclusion - it looks good at the moment, but the current conditions should continue for a while before the evacuation will be lifted. The authorities, who are still at the scene with a lot of Civil Defense, Rescue and Aid personnel are not wanting to take any risk. Another good sign is that the deformation remains at 35 mm for many days in a row.

Update 02/10 - 22:12 UTC : After a period of relative calm the stronger earthquakes started again around Sunday noon (UTC). We have observed 18 volcanic earthquakes of equal or more of Magnitude 2. The strongest one measured 3.7 ML. 5 earthquakes exceeded ML 3.0. NO change in the depth of the hypocenters. The Canary Island authorities have no real news, they just stated that the "Yellow Alert" is maintained. This situation can go on for many days even many weeks. Earthquake-report.com will keep an eye on what happens and will report it in this article if something significant develops.

Update 02/10 - 07:33 UTC : Since 3 days we notice a serious weakening of the seismic activity. Yesterday only 5 quakes from Magnitude 2 or more have been recorded. The 7 first hours of today : 0
Earthquake-report.com expects that the authorities will soon change the alert level to "Green" if the present situation continues.

Update 01/10 - 16:32 UTC : Since the very beginning of the volcanic earthquakes (July 17) until September 30, IGN has counted 8,862 tremors. The strongest one had a magnitude of 3.8. Only 55 of these earthquakes were felt by the islanders. Almost all of them had a focal depth in between 10 and 15 km. Yellow alert is also maintained today.

De los 8.862 sismos detectados por el IGN en El Hierro, 55 han sido sentidos por la población
- La magnitud mayor de esta serie alcanzó un valor de 3.8 en la escala de Richter
- El Gobierno de Canarias mantiene la situación de semáforo amarillo, según las recomendaciones de los científicos del IGN
Hasta el 30 de septiembre, la red de vigilancia volcánica de seguimiento 24 horas del Instituto Geográfico Nacional (IGN), ha registrado y localizado desde el pasado 17 de julio, 8.862 sismos, con epicentros tanto al norte como al sur de la dorsal NW y profundidades entre 10 y 15 km. El número de eventos sentidos por la población es de 55, con intensidades II, III y IV en la escala M.S.K. La magnitud mayor de esta serie alcanzó un valor de 3.8 en la escala de Richter.
En los últimos días, los científicos del IGN, órgano oficial para la vigilancia volcánica, han detectado un desplazamiento del fenómeno hacia el sur de la Isla, sobre el Mar de Las Calmas. Hasta que esta tendencia no se confirme por los propios científicos, el Gobierno mantendrá el semáforo amarillo, recomendando a la población que esté atenta a los comunicados oficiales y que aplique las medidas de autoprotección difundidas, ya que todavía se están produciendo movimientos sísmicos.

Update 30/09 - 21:59 UTC : The PEVOLCA board (authorities + scientists) is maintaining the "Yellow Alert". Once more PEVOLCA declared that the volcanic earthquakes have stabilized and that the most recent action is moving to the south in the Las Calmas Sea (epicenters). This can also be seen on the map below (red bullets). They also said the the strength of the quakes was weakening (as we also have noticed and reported earlier). The Los Roquillos tunnel remains closed because of a persisting landslides risk.

Update 30/09 - 16:32 UTC : Tom Pering (volcanologist): With the increase in strength of seismic episodes beneath El Hierro the authorities have raised the alert level to yellow. This means that they see that the chance of an eruption occurring is possible. However, the location of the earthquakes are still deep (mostly below 14 km), which means that we are probably not seeing the movement of magma to the surface in ready for an eruption.
For the moment it seems as though magma is still moving beneath El Hierro and potentially filling a magma chamber. It is good to remember at this point that roughly only one in every ten magma intrusions ever reach the surface as an eruption. Keep watching, as it is still too early to tell what will happen.

Update 29/09 - 20:44 UTC : New press report from PEVOLCA (committee of authorities and scientists) has decided to :
- allow the return of residents of Los Corchos, El Lunchon and calle Carrera to their houses.
- The Los Roquillos tunnel remains closed until further notice
Reason : same level of volcanic earthquakes and the epicenter of the tremors is moving to the south into the ocean.

Update 29/09 - 17:44 UTC : NO new press reports from the authorities today. Less earthquakes than yesterday (20 above or equal to Magnitude 2 - midnight UTC until 17:23 UTC)). More powerful tremors though. 10 tremors above or equal to magnitude 3.0. The strongest one was 3.8.
Scientists are guessing that the chance on an eruption will be max. 10%. Main reason the continuous depth of the magma movements in between 10 and 15 km. The increasing magnitudes are not giving any clue on a near eruption as the magma would have to find its way to the surface. So far we do not see shallow earthquakes.
All scientists are looking with a magnifying glass to the events and are not alarmed yet.
As said before, the precautionary measures that the authorities have declared are for EARTHQUAKES and LANDSLIDES reasons, NOT for a near eruption.
We are also following the events with a magnifying glass, so please return regularly for eventual

Update 28/09 - 23:24 UTC :We have counted 38 tremors today equaling Magnitude 2 or more, the latest one being a 3.5

Update 28/09 - 23:22 UTC : New Press Report from the Government of the Canary Islands and the local authorities of El Hierro via PEVOLCA
The steering committee has noticed that the activity has weakened a little bit. Some landslides have been reported in the mountains (some villages were evacuated mainly for this landslide risk)
- schools are reopening on Thursday in Frontera
- The Roquillos Tunnel remains closed until further notice
Furthermore, the Canary Islands government has taken additional precautionary measures to be perfectly ready if the situation would deteriorate suddenly.
Additional equipment and personnel have been send to the island. Among them, vehicles equipped with satellite communication material, SUV's, 2 coaches and 2 other vehicles for transporting people, etc.
The Red Cross from his part has strengthen material and personnel on the island to be ready if called. @ earthquake-report.com we have the impression that the Canary Island government is doing all they can to avoid panic and to be ready if something unexpected would happen. We congratulate the authorities with the way they manage the situation.
The read the Full Report in Spanish, Click Here

Update 28/09 - 08:14 UTC : Tremors are continuing also today. Since midnight UTC El Hierro had 10 +2 earthquakes, 3 of them at magnitudes 3.0, 3.3 and 3.4 at a depth in between 15 and 17 km (no change)

Update 28/09 - 00:26 UTC : A local Tenerife newspaper (Laopinion.es) has a few interesting notes on "worst case scenarios"
- the entire population of the island can be evacuated by 5 boats in less than 3 to 4 hours!
- as written earlier in this article, some people are predicting silly scenarios like giant explosions which could generate even mega tsunamis reaching the east coast of the USA. Hard to believe, but these are circulating!
Well to contradict such Armageddon scenarios, IGN scientists have emphasized that a possible eruption at El Hierro will have a low explosive value. We recommend reading a very well written article (in Spanish) here.
If if if if .... (what nobody expects at this time) an eruption would occur, Scientists of IGN are expecting activity similar to the October 1971 La Palma eruption (see video).
Canary Island eruptions are generally 'Strombolian', similar to Hawaii and Sicily eruptions.
La Palma October 1971 eruption video - an eventual eruption is expected by scientists to be the same style

Update 2 September 27, 2011 - 23:38 UTC : Our update 1 gave a lot of speculation on : what now ? Nobody could deny the increasing tremor activity below El Hierro.
Since our list below 12 new M2+ earthquakes occurred before midnight. This makes today's total 33 +M2 earthquakes!
The government from the Canary Islands and the local El Hierro authorities are "fearing more the potential" earthquake / landslide risks than a possible eruption at this point.
Tonight the Cabildo de El Hierro has decided 2 important new precautionary measures :
a) Schools will be closed until further notice as a preventive measure
b) The Los Roquillos tunnel will be closed from 23:00 (11 PM) on and this until further notice.
Los Roquillos Tunnel connects the villages of Valverde and Frontera.
People living in houses in the following communities : Las Puntas; Sabinosa; Pie Risco; Pozo de la Salud y Guinea have been asked to evacuate to community buildings in Frontera.

The government of the Canary Islands makes a new appeal to the population to stay calm and repeats once again that an eruption is not eminent and the the present "semaforo Amarillo" (we call it Yellow Alert) remains UNCHANGED since it was called on Sunday (NO deterioration only an increasing earthquake risk)

The biggest part of the "Nota Informativa" (Informative report) describes what to do during a serious earthquake, of course nothing special for the regular readers of this site. All the text can be described by 3 words : Drop, Cover and Hold (click here for our informative article)

Here is the full press report as published by the "Cabildo El Hierro"

El Gobierno evacua esta noche 300 personas de Frontera por riesgo de desprendimientos
- Se cierran los centros educativos del municipio como medida preventiva
- El Cabildo de El Hierro decide cerrar el túnel de Los Roquillos a partir de las 23 horas hasta nuevo aviso
El Gobierno de Canarias, ante el riesgo de desprendimientos asociados al fenómeno sísmico volcánico de El Hierro, y siguiendo las recomendaciones de los científicos del Instituto Geográfico Nacional (IGN) que prevén un incremento de la intensidad y frecuencia sísmica a partir de la media noche, va a proceder a la evacuación preventiva de algunas viviendas de la zonas de Las Puntas; Sabinosa; Pie Risco; Pozo de la Salud y Guinea, en el municipio de Frontera.
El número de personas que se estima desplazar a la Residencia Escolar de Valverde y al Cuartel Militar Anatolio Fuentes de La Caleta, será de aproximadamente 300 personas.
Asimismo el Cabildo de El Hierro procederá a cerrar el túnel de Los Roquillos a partir de las 11 de la noche de hoy hasta nuevo aviso
Como medida adicional, la Consejería de Economía, Hacienda y Seguridad ha trasladado a la Consejería de Educación, Medio Ambiente y Sostenibilidad, la necesidad de cerrar los colegios del municipio, por si hubiera desprendimientos que afectaran a las carreteras.
El Gobierno de Canarias quiere lanzar un mensaje de tranquilidad a la población y recordarle que estamos en semáforo amarillo, tal y como se estableció el pasado 23 de septiembre, y que no se espera una erupción inminente.
La sucesión de movimientos sísmicos puede incrementar su frecuencia e intensidad por lo que es conveniente que los ciudadanos tengan también en cuenta las siguientes recomendaciones:

Si está en el interior de un edificio es importante:
No salir del edificio hasta que finalice el movimiento.
Buscar refugio debajo de estructuras fuertes.
Mantenerse alejado de ventanas, cristaleras, vitrinas, tabiques y objetos que pueden caerse y llegar a golpearle.No esté en la cocina.
No utilizar el ascensor.
Si el movimiento es fuerte, una vez finalizado, apague el suministro de luz, agua y gas.

En un edificio público (supermercado, cine, biblioteca, etc):
No corra despavorido hacia la salida.
Aléjese de ventanas o puertas de cristal.
Protéjase debajo de estructuras fuertes.
En espacios con estanterías (bibliotecas, archivos, supermercados, etc.) salga de los pasillos donde se encuentran las estanterías y agáchese, de rodillas, junto a los laterales de las estanterías.
En la escuela haga que los niños y estudiantes se arrodillen debajo de su pupitre, poniéndose un libro sobre la cabeza.

Si la sacudida le sorprende en el exterior es conveniente:
Guarde la calma y haga que los demás la guarden.
Procure controlar cualquier situación de pánico.Ir hacia un área abierta, una vez alejándose de los edificios dañados.
Si hubiera edificios dañados, no entre en ellos.
Si está circulando en coche detenga lentamente el vehículo, procures no bloquear la carretera.
Encienda la radio para conocer de las autoridades la situación y las recomendaciones en especial por posibles bloqueos de carretera.
Las autoridades indicarán las medidas de protección a tomar a través de los Medios de Comunicación, los Centros de Información y los Centros de Filiación y Registro.

Intente responder a las llamadas de ayuda y colaborar con los Servicios Intervinientes, pero no acuda a las zonas afectadas sin que lo soliciten las autoridades.Es importante evitar curiosear por las zonas siniestradas; esto es peligroso y además dificultará las labores de rehabilitación.


Update 1 September 27, 2011 - 17:12 UTC : No special alerts on the www.emergenciaselhierro.org website, but we have noticed that EMSC listed 21 +2 magntude tremors on September 27 (00:00 until 17:12). Some tremors have been felt by the people living on the island which will probably make them even more nervous. The strongest ones were 3.4, 3.6 and 3.8.
The depth however is still at an average of 15 km. The most shallow ones are still at a depth of 11 km below the surface.
The 3.5 and 3.8 magnitude quakes have been felt on the island as weak shaking MMI III
At the point of publishing this update, the alert remains at "Amarillo" (Yellow)
Date Time Depth Magn
2011-09-27 16:04 11 2.6 CANARY ISLANDS, SPAIN REGION
2011-09-27 15:44 17 3.8 CANARY ISLANDS, SPAIN REGION
2011-09-27 14:59 16 2.5 CANARY ISLANDS, SPAIN REGION
2011-09-27 14:38 11 3.6 CANARY ISLANDS, SPAIN REGION
2011-09-27 14:27 17 2.6 CANARY ISLANDS, SPAIN REGION
2011-09-27 14:18 13 2.7 CANARY ISLANDS, SPAIN REGION
2011-09-27 12:35 16 2.5 CANARY ISLANDS, SPAIN REGION
2011-09-27 12:31 16 2.8 CANARY ISLANDS, SPAIN REGION
2011-09-27 11:46 15 2.5 CANARY ISLANDS, SPAIN REGION
2011-09-27 11:31 15 2.5 CANARY ISLANDS, SPAIN REGION
2011-09-27 11:23 17 2.6 CANARY ISLANDS, SPAIN REGION
2011-09-27 11:00 14 2.6 CANARY ISLANDS, SPAIN REGION
2011-09-27 09:58 15 2.5 CANARY ISLANDS, SPAIN REGION
2011-09-27 09:53 15 2.5 CANARY ISLANDS, SPAIN REGION
2011-09-27 09:37 16 2.7 CANARY ISLANDS, SPAIN REGION
2011-09-27 09:32 14 3.4 CANARY ISLANDS, SPAIN REGION
2011-09-27 08:43 15 2.7 CANARY ISLANDS, SPAIN REGION
2011-09-27 08:16 12 2.6 CANARY ISLANDS, SPAIN REGION
2011-09-27 08:04 15 2.9 CANARY ISLANDS, SPAIN REGION
2011-09-27 07:58 16 2.6 CANARY ISLANDS, SPAIN REGION
2011-09-27 07:42 16 2.6 CANARY ISLANDS, SPAIN REGION

Update September 26, 2011: Edward Lane, a regular reader of our volcano articles, informed us of a great 4D Quake Plot video which we have embedded.
Looking at the 4-D plotting of all current earthquakes, one can clearly see that the majority of tremors is still at a depth of 10 to 15 km, not directly below the island as it often is with other active volcanoes.

Update September 25, 2011: El Cabildo de El Hierro sends a message of calm and security to the population.
The president of the Cabildo de El Hierro, Alpidio Armas, and the Minister of Security and Emergency Area, Maria del Carmen Morales, have appeared before the media on Sunday, September 25, to convey a message of calm and security to the population.
Main reason, the strongest earthquake so far (Magnitude 3.4 at a depth of 15 km).

Update September 25, 2011 : Rumors are circulating that a possible eruption of El Hierro volcano would lead to a giant tsunami. Every special effect in nature is translated by some people into wild disaster scenarios. Such a treat is highly unlikely (based on the seismicity mainly below the island). A below sea level eruption is highly unlikely. We are convinced that the Government of the Canary Islands and the scientists of the committee would certainly report such information when a dangerous situation could not be excluded. + Is is far from sure that an eruption would occur, even with more tremors and the current deformation.

The Canary Islands government has set the 'yellow alert' for the population of El Hierro as a lot of volcanic tremors are continuing to occur below the island since last July.
The 'yellow alert' decision bas been after consulting the PEVOLCA, and is based on the conclusions of the meeting of the Scientific Committee. The committee met on Saturday morning in El Hierro. Main reason for the alert increase where the increasing number of volcanic earthquakes as well as deformations (up to 30 mm change from the beginning).
The current 'yellow alert' phase does not mean that an eruption is eminent, but that the population will be informed on the risks and will be informed how to take certain protective action.
At this stage the 'Cabildo de El Hierro' will be responsible for informing the public of the practical aspects of the action plan including meeting points, shelters and evacuation plans.
The website is www.emergenciaselhierro.org.
The Canary Islands government will report weekly on the evolution.

Image courtesy ign.es

Interesting links
Map of El Hierro with the seismic activity projected on it
Graphic of the number of earthquakes and their depth since July 18
Deformation graphics (look at the stations HI01 to HI04)

GPS Deformation Image courtesy ign.es

Text (in Spanish) of the press release by the Government of the Canary Islands on Saturday September 24

Ante ciertas variaciones del fenómeno en los últimos días
El Gobierno de Canarias eleva a semáforo amarillo la situación sismo-volcánica de El Hierro
• Esta fase implica mayor información la población y la planificación de recursos
El Gobierno de Canarias ha establecido el semáforo amarillo para la población de El Hierro ante las variaciones del fenómeno sismo-volcánico que se está produciendo en la Isla desde el pasado mes de julio.
Esta decisión, tomada en base al Plan Específico de Protección Civil y Atención de Emergencias por Riesgo Volcánico (PEVOLCA), se ha basado en las conclusiones de la reunión del Comité científico del Plan, reunido esta mañana en El Hierro, que ha informado sobre los cambios apreciados en la energía sísmica liberada así como en las deformaciones.
Esta fase, de preemergencia por riesgo volcánico, implica una mayor información a la población y de tomar ciertas medidas de autoprotección en el caso, todavía poco probable, de que se produzca una erupción.
Asimismo, las instituciones competentes en materia de Seguridad y Protección Civil, y en el marco del Comité Técnico celebrado a continuación, han definido esta mañana, el plan de actuación en el que se establece los procedimientos eficaces para garantizar la integridad y bienestar de la población que pudiera verse afectada por una situación de emergencia en el ámbito de este Plan. La elaboración de este documento es una de las medidas que establece el PEVOLCA cuando la situación se encuentra en Semáforo Amarillo y asigna del personal implicado en la emergencia de los Grupos de Acción, la revisión de planes de contingencia de Servicios Básicos Esenciales, la información continuada a la población, la difusión del Plan de Evacuación y la comprobación del Plan de Comunicaciones.
En esta fase el Cabildo de El Hierro será el responsable de informar a la ciudadanía de los aspectos prácticos del plan de actuación según la evolución del fenómeno, de los puntos de encuentro, albergues y sistemas de evacuación. La página web es www.emergenciaselhierro.org.

El Gobierno de Canarias informará semanalmente sobre la evolución del fenómeno, siendo el portavoz único para trasladar la información científica. Asimismo habilita una página web específica, que se podrá consultar en www.gobiernodecanarias.org/dgse/sismo_hierro.htmlGabinete de Prensa. Consejería de Presidencia, Justicia y Seguridad 922 476 520 922 476 731 928 306 446
rlortri@gobiernodecanarias.org; avidgon@gobiernodecanarias.org, ralotal@gobiernodecanarias.org

El PEVOLCA engloba, en diferentes órganos, a diversas instituciones como son el Instituto Geográfico Nacional, el Consejo Superior de nvestigaciones Científicas (CSIC), la Agencia Estatal de Meteorología; la Delegación del Gobierno, el Cabildo de El Hierro, el Cabildo de Tenerife y el Instituto Volcanológico de Canarias, en este caso, además intervinientes de Protección Civil, Fuerzas y Cuerpos de Seguridad, y los alcaldes de los municipios de El Hierro

Recomendaciones a la población contempladas en el PEVOLCA Color amarillo:
Una vez declarada la fase amarilla significa que hay que prepararse ante una evolución desfavorable del fenómeno, y lo más importante es estar atentos a los mensajes oficiales de prevención y autoprotección que serán específicos para las zonas de riesgo. Las medidas generales que se toman en las zonas de mayor riesgo son los siguientes:
· Escuche la radio o mire en la televisión los informes oficiales sobre la actividad volcánica y su evolución. Es conveniente tener una radio a pilas.
· Para cualquier aclaración adicional llame al 012
· También estarán disponibles las páginas de Internet del Gobierno de Canarias y de, en este caso, el Cabildo de El Hierro.
· Asegúrese de tener en casa la documentación personal de toda la familia y de la vivienda organizada y agrupada para poder transportar lo más importante.