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El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6

Creato il 16 agosto 2012 da Tnepd

This is Part 49 of the El Hierro Volcano eruption report

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With the collaboration of Joke Volta, an El Hierro resident and Julio del Castillo Vivero, photographer.
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Update 06/07 – 14:28 UTC
- 46 earthquakes so far today
- NO change in the other parameters

Update 06/07 – 14:28 UTC
- A new Pevolca reports confirms what we have written earlier today and yesterday. Additionally IGN has reported that also the islands of Tenerife and La Palma are moving horizontally. The El Hierro activity cannot be the only reason for this horizontal deformation. IGN also sampled air and water in the earthquake epicenter area and has found no abnormal values.

Update 06/07 – 13:34 UTC
- 25 earthquakes so far today
- As could be expected, Joker reports : no visible action today
A new series of pictures from Joke Volta from this morning.

El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6

Update 06/07 – 11:25 UTC
The volcano action has almost come to a standstill compared by the action since June 24, however :
- IGN has still listed 24 earthquakes from midnight until 09:24 UTC.
- a lot of smaller earthquakes are still continuing, even though they area not listed by IGN (we have counted at least 64 so far today)
- 99% of the earthquakes are or in the Las Calmas sea, south or west of the lighthouse or below the western part of the island. One exception, a weak M1.5 quake in the El Julan area below the island (quake area 2011 eruption), depth : 20.7 km.
- The average depth remains (just as the last couple of days) between 18 and 21 km
- CHIE seismogram seems to be out of service since more than an hour
- The GPS data from the Involcan / Univ. of Nagoya are giving a mixed picture of the deformations! Click here for the stations list. All deformations are approx. – we have to use the graphs from the link.
FRON: Horizontal : east : stabilized, north : a few mm – Vertical : decrease of 0.5 cm
PINA: Horizontal : stabilized, Vertical : strong vertical rise (nearly 1 cm) – strongest vertical increase today
JULA: Horizontal : no new data
SABI: Horizontal : east : a few mm, north : nearly 1 cm – Vertical : further vertical rise of a few mm
REST: Horizontal : a few mm to the west and a few few mm to the north – strong vertical deflation (nearly 2 cm)

El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6


Update 05/07 – 23:00 UTC
- 90 earthquakes until 23:00 hours today. This looks like nothing compared to the last couple of days, but 90 earthquakes is still a big number
- No change in the other parameters (epicenters area, hypocenters depth, HT)

Update 05/07 – 13:46 UTC
- Mr Alpidio Armas, president of the Cabildo El Hierro, has published a press report blaming Pevolca for Tuesdays communication of a new vent close to the beach without having a confirmation of it from scientists. Mr. Armas said that this would unmistakably hurt tourism to the island.
- 56 earthquakes so far today
- the hypocenter depths are again in the 18 to 21 km range
- New Pevolca press report with nothing new (deformations are stabilizing)
- A few images of a stormy Las Calmas sea this morning. No stains or Jacuzzis reports Joke Volta

El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6

Update 05/07 – 12:04 UTC
- The number of earthquakes is quickly running up due to the latest swarm (update 10:04)
- A lot of the earthquakes are now happening in the 16 to 18 km layer, which, if prolonged can throw another light on this eruption and, more to the east could reach the lava tubes of the 2011 eruption. The next 12 hours will certainly give us a better view.
- deformation is down in most of the stations (IGN deformation stats), Involcan numbers are unsure (when will BOTH organizations finally show faint vertical lines in order to read the date of the markings!!)

Update 05/07 – 10:04 UTC
- A new series of earthquakes has started at 09:38 UTC – Magnitude range : 2.5 to 3.0 (so far). Click here to visualize.

Update 05/07 – 07:20 UTC
- 104 earthquakes were listed by IGN yesterday
- 18 earthquakes so far today (the smallest number since the start of the swarm on June 24)
- NO harmonic tremor detected
- El Hierro has lived a calm night with a max. earthquake of Magnitude 2.6.
- NO change in hypocenter depths
- Almost NO change in the epicenter locations (west of the lighthouse) on the exception of 1 earthquake which occurred at a depth of 19.2 km (05:41 M1.8) on the beach a few hundred meter next the location were the GES heli had spotted some activity the day before yesterday (providing that the IGN data were accurate), but there is 99% chance that this is a coincidence.
- No new deformation numbers yet


Update 04/07 – 22:38 UTC
- Apart from the false jacuzzi and stain detected spot, everything was really calm today. The increasing deformation is remaining a factor of concern.
- The magma seem to be imprisoned very well at a depth of 18 to 21 km, so no concern there neither.
- 96 earthquakes so far today.
- Joke has made an effort tonight to make some nice pictures from the Las Calmas sea. She saw the SAR airplane flying along the coast (see image), very carefully spotting every location and measuring temperatures with their infrared cameras. A normal activity from this plane says Joke.

El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6

Update 04/07 – 20:04 UTC
ER Reader Benjamin has posted a question in our comment section which we like to reply here as we think a lot of people are struggling with it too. What do mean the Ultra Rapid, Rapid and Final GPS values which we refer too. We found some good references in the IGS website. The IGS is a voluntary federation of many worldwide agencies that pool resources and permanent GNSS station data to generate precise GNSS products. In general, you can think of the IGS as the highest-precision international civilian GPS community.
Below just an example of what is avable today, but accuracy and frequency are always getting better.
El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6Ultra-rapid
Ultra-rapid products are available for real time and near real time use. The Ultra-rapid products are released four times per day, at 03:00, 09:00, 15:00, and 21:00 UTC. In this way the average age of the predictions is reduced to 6 hours (compared to 36 hours for the old IGS Predicted products and 9 hours for the twice-daily Ultra-rapids).
Rapid
The IGS Rapid products have a quality nearly comparable to that of the Final products. They are made available on a daily basis with a delay of about 17 hours after the end of the previous observation day; i.e., the IGS Rapid products are released daily at about 17:00 UTC. For most applications the user of IGS products will not notice any significant differences between results obtained using the IGS Final and the IGS Rapid products.
Final
The IGS Final products have the highest quality and internal consistency of all IGS products. They are made available on a weekly basis, by each Friday, with a delay up to 13 (for the last day of the week) to 20 (for the first day of the week) days. The IGS Final products are the basis for the IGS reference frame and are intended for those applications demanding high consistency and quality.

Additional interesting comment from ER reader Phil : The reason for the accuracies of ultra rapid, rapid, and final is linked to the GPS system used to measure them. The satellite orbits are predicted ahead of time and measured from refernce stations, then corrections are computed based on measurements and used to update the orbit predictions.
so the RAW GPS data for the satellite orbits is not known precisely in advance, because they are perturbed by solar effects, gravitational effects, and the earths magnetic fields. so Ultra Rapid measurements are always less accurate than final measurements because of uncertainties of the SV orbits

Compare this text which what you see on one the GPS graphs of the Univ. of Nagoya at right and you will understand what is written above.We do however not know at what frequency the Univ. of Nagoya is posting the Ultra Rapid values.
The black crosses are the UR ones, The red circles the Rapid ones and the blue squares the Final values. The UR values are removed after a few days as they R values are more accurate.
IGN does only posts Rapid (once a day) and Final ones.

Update 04/07 – 14:50 UTC
- Part 48 of the El Hierro activity has just been created. The only reason we have to cut parts of this article is the length of it. Since about one year Earthquake-Report.com has adopted this approach instead of always creating new pages. Once we have started a story, people know where they can find the latest news. Part 48 describes what happened in between June 29 and July 1. Link to this part can be found at the bottom of this page.

Update 04/07 – 14:27 UTC
- The local (wise) fisherman have been proved right so far.
Not official yet but Islanders are writing : “El PEVOLCA confirma que no se observan parámetros anómalos en la zona sobrevolada por el helicóptero del GES. Científicos del INVOLCAN, que portaban una cámara térmica, y del Instituto Geográfico Nacional no han observado parámetros anómalos en el vuelo de reconocimiento que han realizado esta mañana en el helicóptero del GES, en la zona en la que ayer se atisbó una mancha blanca en el mar y burbujeo. Con este vuelo queda definitivamente confirmado que no se han producido cambios significativos en el proceso magmático activo en la isla de El Hierro, aunque se mantiene el análisis de datos de forma continua.”
PEVOLCA confirmed that no abnormal parameters were observed in the area flown by the GES helicopter. INVOLCAN scientists, carrying a thermal camera, and IGN personnel have not observed abnormal parameters during this morning’s recognition flight. The flight has confirmed that there were no significant changes in the active magmatic process on the island of El Hierro. (ER translation)

Update 04/07 – 11:58 UTC
- Joke reports that a GES Helicopter with divers on board has left Frontera a short-while ago. IGN and Pevolca are taking no risk this time and do all they can to clarify the situation.
- Also the IGN GPS stations are showing all a strong vertical uplift today.
- Earthquake epicenters are still concentrated to the south of the lighthouse area, no change in depths.

Update 04/07 – 09:37 UTC
- Joke will try to take a few some zoom pictures from the so called detected emission spot at noon.
- In the meantime, villagers are discussing the new emission location and what they can see on the pictures. Joke reports by SMS that the local fisherman do not believe in a new emission spot but are calling it a natural phenomena, ocean floor sea (sorry if this word does not exist in English as we have no other way to describe it). The phenomena is when the current are stirred over the sea bed and are generating white foam waves at the surface.

El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6

Deformation data courtesy Involcan / Univ. Nagoya, Japan

Update 04/07 – 07:18 UTC
- After comparing new “ultra rapid” deformation data from the University of Nagoya (Japan) we can conclude that horizontal (East) and vertical deformation is increasing again at SABI, REST and FRONT, in fact all GPS stations except PINA monitored by Dr. Takeshi Sagiya. The increase is strongest in the vertical deformation.

Update 04/07 – 06:39 UTC
- Everybody will be curious today whether the new “gas emission” spot will pass the IGN scientists testing or not.
- Even when the GES detection is being confirmed, this is far from being a new eruption. If magma would have been flowing on the present location, big steam clouds would have been seen as the depth is no more than 10 to 50 meters. We haven’t succeeded in finding the actual depth of this location. Google Earth, who is quite accurate in giving Ocean depths, shows a disappointing “o” :) .
- Was the erroneous location data given by the Gobierno in their press report deliberately wrong or just a simple human error?. In 2012 these kind of tricks are no longer holding. Never underestimate a couple of hundred dedicated people who will start searching for secrets :) with todays internet tools. Congratulations to some Avcan detectives who apparently found the spot even earlier than we (what a disappointment to see that :) )
- Hypocenter depths of the earthquakes remains at 17 to 21 km
- 169 earthquakes have been counted (or rather listed) by IGN yesterday
- we have counted 45 “terremotos” so far today
- a very calm seismogram today (and partly yesterday) – 1 week ago we would have called the current seismicity “spectacular”


El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6Very important Update 03/07 – 23:55 UTC
A report from the GSC (Communication department of Canary Islands) has revealed that a helicopter survey unit has noticed a (small) jacuzzi and a white stain at coordinates 27º 4.573” N y 18º03.761” W in the Las Calmas sea approx. 180 meter out of the coast. The images which have been taken by the helicopter will now be analyzed by the IGN scientists. A new flight above the zone is planned for tomorrow.

- Nobody is sure at this moment whether this picture really reveals a new vent or shows just some currents. The similarity is at least what we used to see as colors and as water agitation during the 2011 eruption.

Jon Frimann (Icelandic volcanoes blog) writes an interesting comment which we share : Dike intrusions can happen with and without harmonic tremor. Dike intrusions with harmonic tremor happens mostly at places where conduct is well established. That is not the case now. So I would not trust any signs for harmonic tremors just yet. Harmonic tremor pulse might be seen few hours before the eruption starts. Given my experience and what I did see during Eyjafjallajökull volcano eruption in the year 2010. Given the amount of earthquake activity. I am assuming that some of the magma has reached less depth in the crust without making many earthquakes at present time. The reason for that is magma has easier time to make the rock soft at less depth. Soft rock means few to no earthquakes. How this plays out is all big question that currently nobody has an answer to at the moment. (Thanks to Ian Carson for informing us)
- Below another picture of the detected stain and small jacuzzi (the picture above in natural colors – in the picture below we have increased contrast and sunlight) (All pictures courtesy GES).
- Why all these maps below ? : we tried to use the coordinates as given in all the media, but we could not trace the location which coincides with the picture. Finally we decided to scan the southern coast and we tried to detect the trails along the coast. Once that being done, the google maps matched with the picture.

El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6

El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6

El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6

El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6

El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6

Image of the original picture where contrast increase has been used. The jacuzzi as we know him from the past can well be seen. – Image by Omar Rodríguez Rodríguez via Avcan

Update 03/07 – 20:50 UTC
- A very calm pattern at the moment, but nevertheless with 145 earthquakes so far, more earthquakes than yesterday. No change in hypocenter depth and all the latest earthquakes still centered in a small area west of the lighthouse (most epicenters in the Las Calmas sea close to the coast).

El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6Update 03/07 – 15:41 UTC – very interesting Press Conference
IGN expects new strong earthquakes (up to M4.5-M4.6) for the next 7 days. This has been said at a press conference today. Pevolca does not have the intention the meet soon again if only these earthquakes are continuing as this is expected from now on. Pevolca asks the population of El Hierro to be ready for whatever eventual urgent communication which Pevolca may decide. The Grupo de Emergencias y Salvamento (GES) will be at El Hierro to reinforce the local groups, this to be prepared for whatever crisis to come.
María José Blanco (IGN) has said that an eventual eruption at the present seismic center (Las Calmas sea south of the lighthouse), where depths of the hypocenters are still measured at 20 km, can be excluded at this moment. She said that it also lasted quite some time last time before an eruption took place. The epicenters of the earthquakes had to migrate more than 20 km to the south before the magma found his way up. María José Blanco also said that an eruption on land can be excluded at the moment but that IGN follows up the situation very consciously as all the events are going much quicker than during last years eruption. (compiled by ER from a number of local press reports like Diario El Hierro)
- Already 123 earthquakes so far today

Update 03/07 – 14:50 UTC
- Strong activity started again at 13:40 UTC (14:40 local time) with a couple of serious jolts. The first one was measured at M3.8, the stronger activity is still going on while writing this update
- The PEVOLCA meeting has ended and as expected did not decide too many things. The meeting was also attended by the subscretary of the Spanish Interior Minister. All equipment will be made ready in case El Hierro do need it. The participation of the National entities of the Army and the Guardia Civil (ie for eventual bathymetries) has been guaranteed. A lot of different specialty departments have also attended the meeting (too much to summarize).
The meeting got a detailed analysis of the present situation where was stated that the deformations had a tendency to decrease. (translated by ER).
Link to the official Pevolca press report

Update 03/07 – 11:55 UTC
- Good chemical numbers from Involcan : ? NO SO2 detected so far and no increased CO2 values
- 94 earthquakes so far today
- Joke reports that the authorities are (re)distributing leaflets with instructions on “what to pack in case of an evacuation” and “where to assemble”. Pevolca is meeting at the moment in Tenerife, but ER does not expect shocking measures
- Joke Volta had a hard night to sleep due to the wobbling and decided to leave early in the morning to see what was going on in the earthquake zone. She saw no bubbles, but her images are still beautiful as ever before.

El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6

Update 03/07 – 09:31 UTC
- ER reader Daniel made a fair attempt to calculate the different vectors of the horizontal deformation stations which leads to the source of the magma pressure. Daniel wrote that he took the deformation data from this well known IGN page ( http://www.ign.es/ign/resources/volcanologia/html/deformacionHierro.html ) and used his knowledge about vector-calculating… (a java-applet did most of his work.). The map only shows N-E-deformation – NO inflation! Data used are those from July 2. All drawings on the map (except the numbers of the GPS stations) are Daniels layer.

El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6

Update 03/07 – 09:03 UTC
Joke reports : A lot of people did not slept in El Pinar. Same for the villages in the El Golfo bay neither… I only slept for a few hours so now and then. At six I was on my way to the Tembargena-mountain-top (which has a view on the Lighthouse area), to take pictures…. I did not saw any stain.. It was a hard days night.
- Pevolca will (of course) meet later today to discuss the present situation of sometimes very strong earthquakes. Our expectation : some advise to calm the people and to tell them what to do in case of an earthquake (click here for our worldwide advise) + some limited additional measures to prevent the chance on injuries from landslides. The meeting will be held at noon 13:30 (local time)

Update 03/07 – 07:34 UTC
- Deformation statistics from the University of Nagoya in cooperation with Involcan are showing a strong decrease in Ultra Rapid values in the stations of Sabinosa, Pinar, Frontera and La Restinga. The numbers are showing a reverse effect than last nights earthquakes would have assumed.
- 71 earthquakes so far today, the strongest one being a M4.2 at 2:31
- hypocenter or focal depth range remains as it was, at 18 to 21 km in average. No shallow quakes anymore.
- activity has calmed a lot the last several hours, but earthquakes still occur at normal (what’s normal ?) values of M+2
- the real number of volcanic earthquakes (including the weak ones) is far greater than the 71 mentioned above. How to see that ? Take a quick look at the CHIE graph and count the vertical out-swaying lines, and thats only a portion of it!

El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6

Update 03/07 – 07:29 UTC – yesterdays numbers
- 111 earthquakes on June 2
- 22 earthquakes had a value of M3 or higher on June 2
- Hypocenter depths from 17 to 23 km and no more shallow earthquakes

Update 03/07 – 00:22 UTC
- The people who have subscribed to our El Hierro earthquake notifications (see below) must certainly have been surprised by the many M3+ earthquakes (we are subscribed too :) ). It gives an immediate feeling how much people in the area are suffering. A lot of these M3+ earthquakes are being felt by the people (at least part of the people like in Sabinosa, Frontera, El Pinar, etc.) . Most of these earthquakes will not be marked as “sentido” because people are giving up to fill in the IGN forms, they rather discuss their emotional feelings at the Avcan FB.
If you are getting annoyed by the many emails (when you have set your level too low, please unsubscribe and resubscribe to a higher value)


Update 02/07 – 23:57 UTC
- What a night ! All this El Hierro strong quakes and it isn’t over yet :(:( especially for the local population
+ a short-while ago : a strong earthquake to report near the Ica, Peru coast.

Important Update 02/07 – 23:16 UTC
- The people from El Hierro will have a bad night sleep mostly based on what to come next ? The latest series of earthquakes are even stronger than earlier today. The latest one being a very strong M4.4 at 19 km depth here (please be aware that these are preliminary data who can be changed after manual intervention).
- We are arriving at Magnitudes were the international agencies like Geofon and USGS will capture the signal and report about it.
- Based on our experience with earthquakes and the type of earthquakes El Hierro is suffering, we do not think that damage will be inflicted (not even slight damage) at less than M5. The biggest danger for El Hierro are the possible landslides due to the strong shocks. We would not be surprised that Pevolca will take safety measures for people living near the Sabinosa cliffs if the strong earthquakes do continue for a while.
- It is a certainty now that this activity is far from over

Update 02/07 – 22:22 UTC
- One of the first “shallower” strong earthquakes so far. At 21:52 UTC a Magnitude 3.6 earthquake occurred at a depth of 11.6 21 km. This depth was preliminary (soon reported after occurrence). Calculation of the earthquake parameters is very complicated and is mostly recalculated by scientists afterwards. In case of this earthquake, IGN personnel will soon work with the data. Epicenter here.
Update 22:37 UTC : As if we knew it, IGN recalculated this earthquake and the new data are 3.4 at a depth of 21 km. This is not exceptional but happens regularly with seismological data.

El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6

El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6Update 02/07 – 20:00 UTC
- 62 earthquakes so far today
- same earthquake patterns than during the morning hours

Update 02/07 – 16:20 UTC
- The set of strong earthquakes have calmed down. A lot of energy in more than 2 hours. 6 of these earthquakes were felt by the people. The epicenter of most of these earthquakes was centered at the southern edge of the western tip of the island (see avcan map at right). All these earthquakes occurred, other than the shallow ones discussed below, at a depth range of 18 to 21 km.
- The map at right shows the epicenters of the latest quakes (taking into account the listed quakes at the time of this update) – image courtesy AVCAN. NO shallow quakes have been reported since our Pevolca report update.
- IGN has listed 47 earthquakes so far today

Update 02/07 – 15:16 UTC
- The new very active seismic period started at 12:30 UTC and is still lasting. 4 stronger earthquakes have been felt by the people (M3.6, M3.4, M2.9 and M3.1)? A lot more earthquakes have to be added to the EQ list by IGN (38 so far today).

El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6

Update 02/07 – 13:09 UTC (updated 14:30 UTC)New Pevolca report – New : Shallow earthquakes
Well, … they seem to be often unfortunate. Just before a new press report arrives, a serious number of stronger earthquakes struck the island. Many of these earthquakes had the same epicenter at the western tip of the island.
- main message today is that seismicity (earthquakes) strongly decreased and that the majority of the vertical deformation was or halted or slightly reversed. All this occurred after the M4.0 has hit the island.
- Pevolca (IGN information) also said that they have recorded 2 shallow quakes (in between 2 and 3 km) with epicenter in El Julan, this after the M4.0 earthquake
- Involcan also refers to new values from GPS station Sabinosa (located in the Centro de Salud from Sabinosa). Click here to see the latest (Ultra Rapid) values from the University of Nagoya. The graph values are these reported by Involcan today.
Link to today’s Pevolca report (Spanish)
Comment ER: no further details on the shallow quakes !
We have filtered the IGN database for shallow earthquakes and found indeed 2 shallow quakes after the M4.0 quake but also 3 other shallow quakes on July 1 before the M4.0 quake. These shallow quakes are also the first shallow quakes since the start of the new swarm. In other words, these shallow quakes are more than just a detail to report. We are looking out to see some more explanations by means of the local press. The last 4 epicenters are all in the same area (at the El Julan side of the old Tanganasoga crater (we have included a video of the overflight of this historic crater)! All the earthquakes were weak to very weak. We have to stress too that none of the strong quakes happened in this area.
Earthquake-report.com has based his information on public available information of the IGN list
This information does not have to lead to any danger or panic. An eruption needs much more than a few shallow earthquakes (CO2 and SO2 gases + a bunch of other scientific data which are measured in realtime by IGN and which are not shared with the outside world). Additionally, IGN is a to be trusted scientific agency which would immediately inform Pevolca if additional action is needed.
01/07/2012 00:22:20 27.8088 -18.1712 Depth 1 km M 2.0 NW FRONTERA
01/07/2012 03:30:38 27.7292 -18.0673 Depth 2 km M 1.3 SW FRONTERA
01/07/2012 06:43:47 27.7367 -18.0839 Depth 3 km M 1.1 W FRONTERA
01/07/2012 20:09:56 27.7202 -18.0700 Depth 3 km M 1.3 SW FRONTERA
02/07/2012 06:32:48 27.7280 -18.0714 Depth 2 km M 1.5 W FRONTERA

Update 02/07 – 13:09 UTC
- Another strong M3.6 earthquake just occurred at 12:51 UTC a little to the south of the lighthouse. The depth was measured at 18 km. This earthquake was (of course) felt in parts of the island.
- Seismicity started to increase approx. 20 minutes earlier

El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6

Update 02/07 – 12:37 UTC
- A shallow M1.5 – 2 km depth earthquake at the steep cliffs of the old Tanganosoga crater has attracted our attention. Shallow earthquakes in combination with increasing deformation will be followed by IGN very carefully.
- The images below (click on them to watch them in our Picasa album) have been made by Joke Volta this morning. Joke told us that she hasn’t seen any unusual colors are water stirring.
- 26 earthquakes so far today

El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6Update 02/07 – 07:48 UTC
- Only 10 earthquakes since midnight, the strongest one being a M2.3 just after midnight
- The hypocenters show a depth of 20 to 23 km. As long as the majority of the action remains at these depths, no infiltration to shallower layers is likely (also because this action does not take place in the vicinity of the older feeding network on these depths)
- 1 earthquake showed a shallower hypocenter at a depth of 16.9 km, this to the south of the lighthouse and closest to the old vent
- the following hours and days will be decisive whether this swarm comes to an end (for how long ?).

El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6


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


Volcano Discussion Panel : If you are a person who wants to discuss and read about all aspects of volcanoes, this discussion panel might be a very good place to hang around. Especially if we start speculating about what to happen next.

El Hierro Volcano eruption (Canary Islands) : Part 49 – July 2 until July 6 zTime goes here

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