[aktueel] Vulkaanuitbarsting bij Canarische Eilanden #3

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Op woensdag 14 december 2011 20:57 schreef Tokamak het volgende:

[..]

Nouja, niet alleen rood. Ik zie ook blauw, groen, geel, paars en oranje voorbij komen

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15/12/2011 @ 09:01 – The IGN has confirmed the stabilisation of the underwater eruptive process in shallow waters to the south of La Restinga as there is a marked decrease in seismicity, reaching the lowest values ​​since the eruptive process began on 10th October 2011. They have said that in the current situation is not considered necessary to maintain constant 24 hour surveillance. It will continue monitoring the activity and its assessment in terms of scenarios, and the issuance of periodic reports and decision making.

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Update 15/12 – 08:04 UTC
PEVOLCA will stop its 24 hours surveillance in La Restinga but the Center for Permanent Care (CAP) will stay open at La Restinga from 08:00 until 20:00 daily. In between 20:00 and 08:00, people will have the possibility to call a guard able to give answers to most questions or urgencies. Pevolca (based on the data delivered from IGN) says that there is NO indication the the process is deteriorating or is becoming more dangerous. IGN reported the eruption process to be stabilized.
Pevolca also said that if whatever new indication of a reactivation will be noticed, they will return to 24 hour surveillance instantly. The decision has no influence on the alert levels currently in place at the Island (yellow alert at the entire island and red alert in a radius around the Las Calmas sea vent).
Earthquake-Report.com who follows the eruption process from the very beginning confirms that the IGN prognosis have always been right until now, although it was often criticized. The alerts were initially called for the landslide risks and the weak to moderate earthquakes in the El Golfo and Puerto Naos areas and as it was not sure in which area the volcano would show up (since the beginning of the eruption on October 10, there were never other vents localized except the line of the current vent (multiple vents at the beginning of November along the Naos coast). (source Joke Volta and the local press)

Data Update 15/12 – 07:59 UTC
- NO earthquakes since midnight
- very strong rise in general harmonic tremor at 01:21 UTC tonight. 40 minutes later back to medium. Bursts as intensive and as much as yesterday. Longest bursts lasted almost 10 minutes
- vent outlet is very defined this morning due to the strong westerly current
- IGN said yesterday that some bursts of harmonic tremor are being felt by local people in La Restinga
- stain as usual

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The nightly burning boat the final word of a volcanologist
Hmmm. I have carefully watched the videos of the strange lights recorded by the web cams on the evening of 14 December, and I am more than ever convinced that they are absolutely NOT related to volcanic activity, take a volcanologists word for it. The way the lights are moving from about 02:30 min in the second (shorter) of the night videos is clearly indicative of a ship. Theres no way in the physical word that incandescent rock will remain persistently incandescent when its in the middle of water, any piece of incandescent rock would be chilled and lose its incandescence at least on the surface.
Boris Behncke from the INGV-Osservatorio Etneo, Catania
[bron]

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Update 15/12 – 08:04 UTC – Why a ship ?
- As you all know IGN almost immediately said that is was a boat. The reason why will be explained a little later in an interview we will publish from Joke Volta with Carmen Lopez, chief scientist of IGN at El Hierro.
- People of El Pinar went to the viewpoint and said also “it is ‘probably’ a boat“.
- Joke talked to a number of people and they said that they had seen a boat at the Lighthouse horizon of the Las Calmas sea.
- Next, Joke looked with her binoculars from El Pinar high above the sea and could see some lights at the horizon.
As Joke knows the location of the vent very well, she was more or less convinced that it could not have been the vent but what else than a boat. The location of the webcams is totally different as they are installed on a hill near La Restinga. We @ ER started looking into to real time navigation maps, but we could not detect a ship to the south of El Hierro.
- This morning she saw this boat again and she started looking in the internet for the name and position. She made a picture this morning and indicated the different positions she saw it (see image below).
- Paul, a ER reader traced the boat this morning on Marinetraffic.com and on http://www.localizatodo.com . The ship was recognized as the C-Whale (see picture below). Paul also said that the only reason we have not seen this ship on the map during the evening and nightly hours must have been that it had switched off his transponders. Why ? Why was it hanging around in that area ? What was he burning ? It does not look like they had a barbecue on board. Nobody knows.
All other questions (easy to come up with more than 5 immediately) will never be solved.
Once again thanks to all for cooperating on this issue. This story has now been finalized.

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Data Update 15/12 15:30 UTC
- NO earthquakes since midnight below or around El Hierro
- OGN has a 1.7 earthquake listed, but the epicenter is located in between Tenerife and Gran Canaria, nothing exceptional
- People living at the Canary Islands looking regularly on the islands seismographs might see the signals of the M 6.3 earthquake at the Kermadec Island (Pacific Ocean) showing up on the seismogram (after 10:10 UTC).
- at 15:40 UTC the vent surface waters showed renew Champagne activity (lot of bubbles)
- harmonic tremor continues to be above medium with regular powerful hydromagmatic bursts (they are sometimes felt in La Restinga)

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Something has changed in the Tremor, but for over an hour no explosions hydromagmatic, Will has taken pressure and keeps out the water in the canal?, The truth is that it has changed their behavior and the explosions have stopped a while. I still no explosions or resume after a while .. see (Enrique)
[bron]

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Data Update 15/12 23:21 UTC
No more earthquakes and a collapse of harmonic tremor at approx. 18:00. The subsiding process started at 13:00 UTC when we saw a period of limited less energized bursts (could be seen on the webcam). It picked up a little bit in the late afternoon to subside almost to 0 around 20:15. At 20:40 we had a new (limited burst) lasting 8 minutes and since then the signal has been stabilized. Another indication of subsiding activity is the lack of bursts during the last several hours.
In a short interview Joke Volta had with Carmen Lopez from IGN earlier today, Mrs. Lopez reiterated that the decision of delegating the nightly surveillance to Madrid had been taken because seismicity (earthquakes) had almost completely stopped and because harmonic tremor was more or less stabilized. The current data analysis showed a stabilization or even subsiding eruption. As far as the signals are this evening the volcano seems to obey and the eruption has drastically subsided.
It might have been a collapse of the vent, as it occurred a number of other times, but during the past processes the earthquakes picked up soon after the collapse. As there is still a remaining signal at the moment the eruption is continuing at a far lower almost survival level (Christmas and New Year holidays vacation ?).
The following hours and days will be decisive for this eruption. If enough magma pressure is left to reopen the vent the activity may increase again. (to be followed)

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Update 15/12 23:55 UTC
One of the people posting a comment in Shipspotting.com, a specialized shipping blog had the following comment on the hanging around location of the C Whale last night :
the most likely scenario is awaiting orders. The tanker market is very poor at the moment and has been for several months. Its certainly not unusual in such circumstances for ships to hang around in the same area doing nothing for weeks, sometimes months on end. The area around the Canary islands is geographically important in this respect as its on the junction of major seaways and means that vessels can go East or West easily should orders come in

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NOTE AVCAN 384 - EARTHQUAKE ACTIVITY-VOLCANIC - HIERRO ISLAND - DECEMBER 15 2011-22:00 h peninsular - seismic-volcanic activity continues to moderate, without seismicity located in the Hierro, but with some weaknesses detected event (18:47, 19: 05 and 11:08 h). Continue an important sign of volcanic tremor in the Restinga area, with an amplitude that was still rising, and is now down and much in the latest hours. In addition, numerous explosions, possibly hydromagmatic, who introduced every few minutes, have stopped at about 13:20 h. At 18:00 h starts to decrease drastically the tremor signal. No new earthquakes located. Before yesterday 0. Yesterday 1. Now go 0. A total of 11,932 earthquakes are located in El Hierro by IGN from 9:00 am of July 19, 2011. (Enrique)

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Data Update 16/12 09:18 UTC
- NO earthquakes since midnight (the latest El Hierro related earthquake occurred on December 14 at 04:02)
- Harmonic tremor gradually picked up since it collapsed yesterday. At this moment it has reached again what we called the main medium tremor from the last couple of days (filled up blue graph). The biggest change is however that the burst are gone, in other words hydromagmatic activity is minor to none.
- The stain is still visible on the eruption webcam in a very windy Las Calmas sea. The active stirring vent cannot be seen anymore.
- Harmonic tremor is still to unstable to allow a prediction of what to come. Will it stop or reactivate ? We will keep you updated.

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Each Wednesday the Volcanological Institute of Canaries will release a weekly graphical informative report about the seismic-volcanic activity of El Hierro (GUAYOTA El Hierro Island), with data about gas emissions (geochemistry), thermometry (geophysics), deformation (geodesia) and seismicity (geophysics) registered by IGN. Besides that, the usual monthly reports about El Hierro will continue.

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NOTE AVCAN 385 - EARTHQUAKE ACTIVITY-VOLCANIC - HIERRO ISLAND - DECEMBER 16 2011-11:30 h peninsular - seismic-volcanic activity continues to moderate, without seismicity located in the iron, and with some weak events detected (00:26 and 03: 30). Continue an important sign of volcanic tremor in the Restinga area, with an amplitude that after the minimum at 20:30 h yesterday, rose rapidly until midnight, and now continues with a lighter rise in the latest hours. In addition, notice some explosions, possibly hydromagmatic, weak, especially after 3 am. No new earthquakes located. Before yesterday 0. Yesterday 1. Now go 0. A total of 11,932 earthquakes are located in El Hierro by IGN from 9:00 am of July 19, 2011. (Enrique)

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A pulse of seven minutes in the tremor changed the upward trend in recent days
[bron]
A pulse of seven minutes in the tremor changed the upward trend in recent days
IGN scientists are not aware that there have been issuing new magmatic material

A pulse of tremor associated with submarine eruption of El Hierro, extraordinarily long, yesterday marked a change in its evolution. Thus, starting at 13:02 hours decreases the frequency and amplitude of the pulses to decay significantly on 18:20 hours. The oscillation of these pulses is considered normal in the evolution of the eruptive phenomenon is visible on the surface. In the stain clearly shows a dark brown head, fairly bubbling in the middle, and a green area, which confirms the presence of gases. IGN scientists are not aware of new magmatic material has appeared on the surface. On the GPS deformation monitoring stations recorded the same pattern of recent days, following the trends of stability in both the vertical component in horizontal components.

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Update 16/12 – 17:59 UTC
- Very unstable harmonic tremor with a couple of very strong bursts in between 16:00 and 17:00. To soon to predict whether the eruption will stop or continue. After each burst the tremor seems to subside strongly and is picking up a little later.
- The UStream webcam from the El Pinar authority is delivering the best images this afternoon. Sometimes, our imagination sees very faint stirring activity.
- Joke had a chat this morning with the RTVC webcam operator. He said that the strong wind was very uncomfortable and that he was allowed to return home today. So, thanks to Joke we know that this webcam (the best of all webcams) is manually operated as well as the reason why ha was down today!
- Joke said that the stain was still visible from above La Restinga but no activity in it
- She also went to the CAP, science center, and had a talk with the IGN man of duty.
- Joke saw the helicopter flying over this morning, so probably we will have new images and video late tonight

Update 16/12 – 23:59 UTC
- Involcan and the Guardia Civil Helicopters made a surveillance flight today. You will see that the eruption has subsided a lot as could be seen on the harmonic tremor graph, but she is still continuing at lesser pace. The gray eruptive vent remained visible and the stain was still very large.

Data Update 17/12 – 09:19 UTC
- A new earthquake measuring 2.3 magnitude occurred 22 km deep below Los Llanillos in the El Golfo area. It will trigger mixed feelings for 2 groups of people. At the one hand the volcano enthusiasts who will see it as a sign that the volcano is not dead yet and at the other hand the local people who are highly irritated with this activity.
- Harmonic tremor was medium all night long with a slightly increasing trend and some occasional short bursts. Yesterday, the tremor subsided strongly after every burst, but this does not happen anymore since 01:00.
- A faint Jacuzzi area can be seen at times in the Telefonica Cabildo eruption webcam (look at the thin white line 1 cm lower than the horizon and vertically above the left harbor wall. The rough see if sometimes blocking the view, but we have seen it many times this morning

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NOTE AVCAN 387 - EARTHQUAKE ACTIVITY-VOLCANIC - HIERRO ISLAND - DECEMBER 17 2011-10:00 h peninsular - seismic-volcanic activity continues to moderate, with seismicity in the Gulf and some weaker event detected. Continue an important sign of volcanic tremor in the Restinga area, with an amplitude that continues with a lighter rise throughout the day with some explosions, possibly hydromagmatic. The magnitude of the earthquake only 2.3. New earthquakes 1. 22km depth. Days ago 1. Yesterday 0. Today they 1. A total of 11,933 earthquakes are located in El Hierro by IGN from 9:00 am of July 19, 2011. (Enrique)

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Update 17/12 15:03 UTC
- The readings of harmonic tremor of the last several hours are indicating that the eruption is not over yet. Medium tremor is not subsiding as strong as before and bursts are again picking up in number.
- Afternoon back-light /glare is blocking a good view of the eruption area in the Las Calmas sea. We expect a better view on what is happening within 2 to 3 hours.
- Joke is a frequent visitor of the CAP / IGN science center in La Restinga and was informed yesterday that IGN has 3 webcams serving their team.
- Carmen Lopez told Joke the day before yesterday that the closure of the La Restinga nightly surveillance will not have any impact on the 24 hours service they are delivering. The eruption is continuously monitored for 24 hours, but in between 20:00 and 08: 00 it is monitored from Madrid. In case of necessity (Madrid seeing some important change) or whenever local people are alerted in La Restinga, the local La Restinga guard will be operational again. If an important change would be noticed, Pevolca will decide immediately to restart the local 24 hours surveillance at La Restinga. Carmen said to Joke that the continuous 24 hours operations are having a serious burden on the IGN personnel. Delegating the follow up to Madrid during the night allows them to work at more comfortable hours.

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NOTE AVCAN 388 - EARTHQUAKE ACTIVITY-VOLCANIC - HIERRO ISLAND - DECEMBER 17 2011-22:00 h peninsular - seismic-volcanic activity continues to moderate, with seismicity in the Gulf and some weaker events detected, including a microseismic swarm from 19:06 to 19:23 h. Continue an important sign of volcanic tremor in the Restinga area, with a stable amplitude continues throughout the day, with some explosions, more and more numerous, possibly hydromagmatic. The magnitude between 1.4 and 1.0. New earthquakes 2. 3km depth. Days ago 1. Yesterday 0. Now go 3. A total of 11,935 earthquakes are located in El Hierro by IGN from 9:00 am of July 19, 2011. (Enrique)

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Update 18/12 – 09:20 UTC
- Bad news for the volcano fans-followers among our readers. The eruption is subsiding further and looses more and more strength.
- We do not know whether there is a direct connection with what happened yesterday afternoon as it can not be linked with the harmonic tremor graph, but we think that there is certainly an indirect relation. Yesterday afternoon 2 weak earthquakes occurred at very shallow depth in the coastal El Golfo area. The first one occurred at 15:24 had a magnitude of 1.0 and occurred at a depth of 3.4 km. The second one occurred 1 minute later, had a magnitude of 1.4 and occurred at a depth of 3.0 km.

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NOTE AVCAN 389 - EARTHQUAKE ACTIVITY-VOLCANIC - HIERRO ISLAND - DECEMBER 18 2011-10:30 h peninsular - seismic-volcanic activity continues to moderate, without seismicity located in the Hierro, but with some weaknesses detected event (04:49 and 08: 45). Continue an important sign of volcanic tremor in the Restinga area, with an amplitude that continues to decrease since the last part more than 50% to half of the signal, with some explosions, possibly hydromagmatic. No new earthquakes located. Before yesterday 0. Yesterday 3. Now go 0. A total of 11,935 earthquakes are located in El Hierro by IGN from 9:00 am of July 19, 2011. (Enrique)

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The INVULCAN continues to record a decrease in the diffuse emission of CO2 by the volcanic system island of El Hierro

This downward trend since late November until now reaching 770 ± 30 tonnes per day

Since last July, scientists at the Institute of Technology and Renewable Energies (ITER), an agency of the Cabildo of Tenerife, and is now part of volcanological Institute of the Canaries (INVULCAN), 10 500 have been more diffuse flow measurements carbon dioxide (CO2) through numerous scientific campaigns on diffuse volcanic gas emissions that have materialized over the entire surface of the island of Isla Meridian. The latest results confirm a downward trend in the diffuse emission of carbon dioxide (CO2) into the atmosphere by the volcano island of El Hierro since late November, when it came to achieving the 2398 ± 115 tons per day, until now reaching to register for an emission rate of 770 ± 31 tonnes per day.

This record to the bottom of the diffuse emission of carbon dioxide (CO2) suggests a potential loss of pressure carbon dioxide (CO2), from late November to date, the system magmatic-hydrothermal volcanic-existing in the Island El Hierro. These results are consistent with the records of seismic activity as well as horizontal and vertical shifts that are registered through permanent instrumental network

The scientific purpose of these campaigns is to investigate spatio-temporal variations of the diffuse emission of carbon dioxide (CO2) into the atmosphere by the volcanic system of El Hierro island since the results thereof can not be obtained through networks permanent instrumental analysis contribute to the evolution of the current eruptive phase is occurring in El Hierro. On the other hand, it is widely accepted that the gases are the driving force of volcanic eruptions and monitoring of carbon dioxide (CO2) in volcanic surveillance programs is very important because not only is the second major component of volcanic gases after water vapor, but also because of its low solubility in molten silicitados (magma) favoring the carbon dioxide (CO2) to escape with their ease of volcanic systems in depth.

These scientific surveys have failed to materialize due to MAKAVOL project "Capacity Building of R + D + i + d to contribute to the reduction of volcanic risk in the Macaronesia (MAC/3/C161)" which is being co-funded by the transnational Cooperation Programme of the European Union Madeira-Canary-Azores (MAC 2007-2013) and the collaboration of the Island Councils of Tenerife and El Hierro.

INVULCAN is an institution demanded unanimously by the Senate (2005), Parliament of the Canary Islands (2006) and House of Representatives (2009) with the aim of contributing to improving and optimizing the management of volcanic risk in Spain.


Picture Pie
Temporal evolution of the diffuse emission of carbon dioxide (CO2) in the island of El Hierro (red circles) recorded by the INVULCAN and the daily number of earthquakes located above magnitude 1.7 by the National Seismic Network (IGN).

[bron]

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NOTE AVCAN 390 - EARTHQUAKE ACTIVITY-VOLCANIC - HIERRO ISLAND - DECEMBER 18 2011-22:30 h peninsular - seismic-volcanic activity continues to moderate, without seismicity located in the Hierro, but with some weaknesses detected event (09:57 and 15: 07). Continue an important sign of volcanic tremor in the Restinga area, with an amplitude that continues to decrease since the last part over 60% in the last 24 hours, with some explosions, possibly hydromagmatic. It seems that in the last hour begins to rebound. No new earthquakes located. Before yesterday 0. Yesterday 3. Now go 0. A total of 11,935 earthquakes are located in El Hierro by IGN from 9:00 am of July 19, 2011. (Enrique)

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Update 18/12 – 23:59 UTC
- Another Involcan / Guardia Civil video from today, but this time with the Panoramic Camera – Video 1 and Video 2
- Involcan confirms that a new vent has opened to the south east of the former vent. The images are similar than those recorded in October. The same kind of vent and stain colors. The vent seems to be limited in size.
- CO2 levels (measured by the Involcan) have decreased further

VUELO CIENT�FICO INVOLCAN - GC 181211 - VOLC�N SUBMARINO DEL HIERRO - NUEVOS BURBUJEOS - PANCAM I

VUELO CIENT�FICO INVOLCAN - GC 181211 - VOLC�N SUBMARINO DEL HIERRO - NUEVOS BURBUJEOS - PANCAM II

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NOTE AVCAN 391 - EARTHQUAKE ACTIVITY-VOLCANIC - HIERRO ISLAND - DECEMBER 19 2011-10:30 h peninsular - seismic-volcanic activity continues to moderate, with seismicity in the Gulf and with some weak events detected (Wednesday 22:23, 02:20, 3:36, 07:41 and some more). Continue an important sign of volcanic tremor in the Restinga area, with an amplitude that has begun to increase since midnight, in more than 20%, with some explosions, possibly hydromagmatic. The magnitude of only 2.0 earthquake is located. New earthquakes 1. 19km depth. Before yesterday 3. Yesterday 0. Today they 1. A total of 11,936 earthquakes are located in El Hierro by IGN from 9:00 am of July 19, 2011. (Enrique)

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NOTE AVCAN 392 - EARTHQUAKE ACTIVITY-VOLCANIC - HIERRO ISLAND - DECEMBER 19 2011-21:30 h peninsular - seismic-volcanic activity continues to moderate-low, without seismicity localized, but with some weak events detected. Continue an important sign of volcanic tremor in the Restinga area, with an amplitude that has begun to increase since midnight, in more than 30%, with some explosions, possibly hydromagmatic. No new earthquakes located. Before yesterday 3. Yesterday 0. Today they 1. A total of 11,936 earthquakes are located in El Hierro by IGN from 9:00 am of July 19, 2011.


^{[voor de betekenis van de kleurtjes]}

WARNING => FOR THE FALL OF EARTHQUAKE, VOLCANIC ACTIVITY, FROM MORNING BRIEFING NOTE THERE WILL BE A ONE DAY, THE IN THE MORNING. This does not mean that there is any special note if there is a surge of activity. (Enrique)

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Update 19/12 23:30 UTC
- NO more earthquakes this afternoon and evening
- CAP science center in La Restinga has confirmed that the the main vent is probably no longer active but that some minor side vents are now erupting. As we could see on the webcam during the day, the location of these vents is a little more to the north-east. IGN will certainly report on this new activity the following day(s).
- AVCAN (Actualidad Volcanica de Canarias) will decrease his number of daily El Hierro reports to one per day as a result of the subsided activity. They will increase their reporting when the vents would reactivate.

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Update 20/12 23:55 UTC
- Harmonic tremor is growing again since the last couple of hours
- At 18:26 UTC a weak M 0.9 earthquake happened at a depth of 11 km below the El Golfo beach area

Update 20/12 23:43 UTC
- Joke has a talk with Maria José Blanco from IGN during the morning hours. Here is synopsis of the answers Joke got on her many questions :
- the current emissions are mainly gas emissions
- gas is part of the erupting magma and while magma is flowing down along the volcano slope, the gas finds his way to the surface
- sometimes the emission of gas is mixed with ashes, but we havent seen or analyzed the ash in the current new vents. We hope to get some samples today as the Salvamar Adhara is out to collect material. At the time of writing this update, no additional details are known.
- escaping gas can also trigger the tremors
- the main emitted gas component is CO². We are anxious to see what will happen with the Involcan CO² statistics as we see a lot of gas coming out of the vents. Since the end of November the measured CO² values are almost constantly decreasing.
- i can also tell you that a new bathymetry mission of the Sarmiento da Gamboa is on its way and will start on Thursday. The Sarmiento will probably only work at night. Joke jokes that we will certainly tell this to our readers as we want to avoid another hoax lava eruption : ) . (ER : we also remind our readers that the harmonic tremor graph will probably show drumbeats caused by the instruments of the Sarmiento).

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As a weak sismito in Frontera afternoon, just below CTAN almost certainly now the IGN maps showing where all the seismic stations on the island, every detail of quality. As the tremor is down, can see and recognize in the smaller earthquakes simogramas since they are not shielded. (Enrique).
1117890 20/12/2011 18:26:14 27.7645 -18.0580 11 0.9 4 W FRONTERA.IHI

[bron]

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NOTE AVCAN 394 - EARTHQUAKE ACTIVITY-VOLCANIC - HIERRO ISLAND - DECEMBER 21 2011-10:30 h peninsular - seismic-volcanic activity continues to moderate-low, with seismicity located in the Gulf, the Julan and mar de las Calmas. Continue an important sign of volcanic tremor in the Restinga area, with an amplitude that has been fluctuating since the last part, with some smaller explosions than other days, possibly hydromagmatic. No new earthquakes located. Days ago 1. Yesterday 1. Today van 2. A total of 11,939 earthquakes are located in El Hierro by IGN from 9:00 am of July 19, 2011.

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Update 21/12 – 11:13 UTC
- 4 out of the last 6 earthquakes we have noticed the last couple of days are occurring at “unusual” depths. Also the 2 earthquakes from earlier today happened at 17.9 km (below land) and 13.1 km (Las Calmas sea) (for details zie hierboven). Just like AVCAN, we also think that these 2 earthquakes occurred in the vicinity of the feeder lava tubes who are connecting the El Golfo area with the Las Calmas sea vent. We are very curious to look at todays satellite picture (will take a few more hours) to find out if other vents have opened, as we cannot see any activity on the webcams.
- The GPS deformation graph which we can see on the IGN website shows NO significant increase but NO significant decrease neither.

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Update 21/12 13:52 UTC
As promised before, our attention this afternoon was also going to the NASA Modis satellite picture. We have mounted 3 pictures under each other, each one showing the stain in another way.
Picture 1 is the visual picture as extracted from the Modis satellite picture of today (lucky that El Hierro was cloud free today)
Picture 2 is the same picture color enhanced but also with the current vent patch (which we made white)
Picture 3 is the same picture color reduced
If you click on the picture a full size version of the extract can be seen.
The NASA modis picture is courtesy NASA Earth Data

plaatje 2 en 3 op earthquacke report te vinden

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Eruptive PROCESS EL HIERRO STILL ACTIVE SIGN AS SHOWN IN THE TREMOR OF THE LAST DAYS.

12/21/2011 ... 18:23 - Ministry of Economy, Finance and Security

IGN has confirmed the location of two earthquakes since Sunday December 18

The National Geographic Institute (IGN) has confirmed the direction of the Civil Protection Plan for Volcanic Risk (PEVOLCA) that shows the signal as the tremor associated with the eruption, the eruptive process in El Hierro is still active. Based on these data, last Sunday, December 18, the signal decreased slightly presenting tremor few intermittent pulses, while on Monday increased very slightly since the beginning of the day until 8:00 am when he held constant, present virtually pulses. On Tuesday, the tremor signal decreased slightly since the beginning of the day until 10:00 hours remaining stable until the night that showed a slight increase.

As for earthquakes during the last three days two movements have been found, none of them felt by the population. The first occurred on Monday, December 19th at 4:09 pm with a magnitude of 2.0 on the Richter scale and 19 kilometers deep. The second, recorded on Tuesday, at 18:26 hours, reached a magnitude of 0.9 and was located at a depth of 11 kilometers.

Deformations

Control stations of the deformation maintain the same pattern of recent days, following in general the same trend of stability in the horizontal components. For its part, the pattern in the vertical components is deflation at the stations south of the island and stability in the rest.

On the spot, during the day on Sunday, it was not easily distinguishable due to the intense surge since the issue seemed weaker. The head could be seen, although less clearly than in previous days, surrounded by a blue-green area.

On Monday, the head of the stain was clearly visible in the morning as a lighter area that was driven by surface currents, while on Tuesday, due to strong winds and the sea state, the head could not be visualized appreciating slightly more surface area affected by the eruption.

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NOTE AVCAN 395 - EARTHQUAKE ACTIVITY-VOLCANIC - HIERRO ISLAND - DECEMBER 22 2011-13:00 h peninsular - seismic-volcanic activity continues to moderate-high, with seismicity located in the Gulf, the Julan and the Sea of las calmas. Continue an important sign of volcanic tremor in the Restinga area, with an amplitude that is increasing with slight fluctuations since the last part with a few more explosions than other days, possibly hydromagmatic. The magnitude between 2.8 and 2.2. New earthquakes 2. 22 and 26km depth. Days ago 1. Yesterday 3. Today they 1. A total of 11,941 earthquakes are located in El Hierro by IGN from 9:00 am of July 19, 2011.

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Op donderdag 22 december 2011 13:40 schreef 1boefje het volgende:
Dus de regelmatige bevingen worden wat minder en rustiger, maar opeens zijn er af en toe uitschieters. Houdt dit weer in dat er magma naar boven komt?
Wat zegt dit?

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Op donderdag 22 december 2011 14:22 schreef 1boefje het volgende:
Maar wat betekend deze verandering dan?
Of weet niemand dat?

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NOTE AVCAN 396 - EARTHQUAKE ACTIVITY-VOLCANIC - HIERRO ISLAND - DECEMBER 23 2011-11:30 h peninsular - seismic-volcanic activity continues to moderate, localized seismicity in the Gulf and the coastal area of Julan to Tacorón Creek. Continue an important sign of volcanic tremor in the Restinga area, with an amplitude that is increasing with slight variations in maximum and minimum intensity approx every 6 hours since the last part with a few more explosions than other days, possibly hydromagmatic. The magnitude of 1.6. New earthquakes 2. 15 and 16km depth. Before yesterday 3. Yesterday 1. Today van 2. A total of 11,943 earthquakes are located in El Hierro by IGN from 9:00 am of July 19, 2011.

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More about volcanic seismology from the OVSICORI:
"The seismic signals originating from volcanic areas, are unique to each volcano and will depend on the activity that counts and that is why many researchers have studied different seismic signals can be recorded in a volcano. Some of them and Minakami, Latter, Chouet, McNut, Koyanagi, White and others have contributed according to their experiences in different active volcanoes and with the advancement in technology in the classification of volcanic earthquakes. "(John Vincent)

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Update 23/12 14:00 UTC
Todays NASA Modis satellite image (from max. a couple of hours ago) shows a very strange picture from the stain and the emission vent. The left white patch is the main vent emission point and small stain. The right white patch at the smallest point of the stain maybe a small remaining cloud patch from the bigger cloud range below it.


en de originele versie

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NOTE AVCAN 397 - EARTHQUAKE ACTIVITY-VOLCANIC - HIERRO ISLAND - DECEMBER 24 2011-10:00 h peninsular - seismic-volcanic activity continues to moderate-low, without seismicity localized, but with some weaknesses detected event (23:06 h yesterday, 00: 13, 05.20, and 6:23 h). Continue an important sign of volcanic tremor in the Restinga area, with an amplitude that is increasing (15%) since the last part, with some explosions, possibly hydromagmatic. No new earthquakes located. Days ago 1. Yesterday 2. Now go 0. A total of 11,943 earthquakes are located in El Hierro by IGN from 9:00 am of July 19, 2011.

Today shows the deformation, especially the HI04 that maintains tendency to deform (Withdraws from la Frontera) and HI03 does not move. FRON also seems that maintains the trend on TN03 and MAZO IZAN (walks).

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Important Update 25/12 – 09:23 UTC
- IGN reported a new M 1.6 earthquake at a depth of 21 km at 01:14. Epicenter in the El Golfo bay
CISC (Unidad de Tecnología Marina del Consejo Superior de Investigaciones Científicas) has reported yesterday that the top of the main vent has collapsed 15 to 20 meter. The new depth was obtained during a bathymetry mission by the research vessel Sarmiento de Gamboa. The acoustic image was made last Thursday and Friday (when we saw the Sarmiento de Gamboa going up and down on the stain) .The white line on the image is the sea floor. The orange tones are reflecting the erupted magma. The suspended material that we can see in the stain and on the emission vents is colored brown (ER: hard to see but on top). The orange colored magma is flowing down along the slopes of the cone.
Last time, the depth of the cone was measured as 140 to 150 meter by the Ramon Margalef. Taking into account the new acoustic study, we can conclude that the depth is now in between 155 and 170 meter, still far away from a Surtseyan eruption.

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NOTE AVCAN 398 - EARTHQUAKE ACTIVITY-VOLCANIC - HIERRO ISLAND - DECEMBER 26 25 2011-10:00 h peninsular - seismic-volcanic activity continues to moderate, without seismicity located with seismicity located in the Gulf and some weak events detected. Continued volcanic tremor signal important in Restinga area, with an amplitude that is increasing (5%) since the last part, after midnight on something and then has vueto up with some explosions, possibly hydromagmatic. The magnitude between 1.6 and 0.9. New earthquakes 2. 15 and 21km depth .. Before yesterday 2. Yesterday 1. Today they 1. A total of 11,945 earthquakes are located in El Hierro by IGN from 9:00 am of July 19, 2011.

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SURFACE AREA IN THE cone of el Hierro volcan has decreased from 15 to 20 M.

24/12/2011 ... 15:47 - Ministry of Economy, Finance and Security

This is a normal process in the formation of volcanic cones that balance adjustments volcanic structure

The Sarmiento de Gamboa oceanographic ship a new acoustic image capture in the area of the eruption

The Marine Technology Unit of the CSIC has informed the direction of the Civil Protection Plan for Volcanic Risk (PEVOLCA) that according to barimétrico recognition by the Sarmiento de Gamboa research vessel the most superficial of the volcanic cone on the island of El Hierro has experienced a small decrease of about 15 to 20 meters. This process, they say, is common in the formation of volcanic cones that undergo rapid growth and a series of adjustments that rebalance the volcanic structure.

In addition, the Marine Technology Unit of the CSIC has provided the direction of an acoustic image PEVOLCA obtained yesterday with one of the Sarmiento de Gamboa fishfinders showing what was happening at the time of image capture in the area the eruption.

In the image, comparable with ultrasound, the white profile corresponds to the relief and topography in the area of the volcano, while orange tones reflect the material being ejected from the volcano.

Also, in the time when the measurement was made, the emission from the volcano reached the surface. Some of the materials were suspended in the superficial zone correspond to the color brown stain is observed on the surface. For its part, the material of orange, it falls from the surface on the flanks of the volcano and the whole area of the eruption.

Tremor and seismicity

On the other hand, the National Geographic Institute (IGN) has confirmed to the direction of PEVOLCA in the day yesterday tremor signal remained at the same values of the previous days although presenting greater variability of long period during the day, no pulses.

As for earthquakes, it is noteworthy that in the day yesterday there were two earthquakes with a magnitude of 1.6 degrees, none of them felt by the population. The first, at 2:16 hours was found in the area of the Gulf and 16 kilometers deep, while the second was recorded at 4:09 hours southwest of El Pinar at a depth of 15 kilometers.

In total, from July 19 11 934 events were located on the island of El Hierro.

Deformations

The control stations maintained a stable pattern deformation in the horizontal COMPONENTS and a tendency towards stability in the vertical throughout the island

With respect to the spot, on the morning of yesterday appreciated the greenish stain extending to the south and no header. During the afternoon there was bubbling in the downtown area and stain issuer extending around to the southeast.

In addition, the report of the flight mission conducted in 103 SASEMAR yesterday afternoon, indicated the detection of a circular well-defined focus in the broadcast area without observing material or surface water vapor. The IR sensor detected an anomaly of 2.2 ° C in the emission from the sea in the background.

Acoustic image of the eruptive process =>
PDF van gister geplaatst plaatje

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NOTE AVCAN 399 - EARTHQUAKE ACTIVITY-VOLCANIC - HIERRO ISLAND - DECEMBER 26 2011-11:00 h peninsular - seismic-volcanic activity continues to moderate-low, with weak seismicity located in the Gulf and some weak events detected. Continued volcanic tremor signal important in Restinga area, with an amplitude similar since the last part (no signal since yesterday after 22:00 h, just looks a bit from 7:00 to 9:00 h) with some explosions, possibly hydromagmatic. The magnitude of only 0.6 earthquake. New earthquakes 1. 12km depth. Before yesterday 2. Yesterday 1. Today they 1. A total of 11,947 earthquakes are located in El Hierro by IGN from 9:00 am of July 19, 2011.

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NOTE 400 AVCAN - EARTHQUAKE ACTIVITY-VOLCANIC - HIERRO ISLAND - DECEMBER 27 2011-10:30 h peninsular - seismic-volcanic activity continues to moderate-low, without seismicity localized, but with some weaknesses detected event (1:13 and 3:28 a.m.) . Continue an important sign of volcanic tremor in the Restinga area, with an amplitude that is on the rise since yesterday at 19:00 h (40%) since the last part, with some explosions, possibly hydromagmatic, especially increasing from midnight. No new earthquakes located. Days ago 1. Yesterday 1. Now go 0. A total of 11,947 earthquakes are located in El Hierro by IGN from 9:00 am of July 19, 2011.

In the spectrogram can clearly see the earthquake of 3:28 pm

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54 Stunning photos of El Hierro and the area of eruption, taken yesterday morning from the Civil Guard helicopter with scientists from INVOLCAN.

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Earthquake of 6.5 in the middle of the Siberian plate in a place where normal is not very powerful so this seismicity. It shows a teleseismic at all stations on line of the Canary Islands, except the CHIE that shielded by the tremor signal, which continues to rise, now is three times stronger in amplitude than yesterday when it began to climb 19:00 pm o'clock
M 6.5 - SOUTHWESTERN SIBERIA, RUSSIA - 27/12/2011 15:21 UTC
[bron]

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Update 28/12 – 08:05 UTC
- 1 hour later it looks like we had a vent collapse as the tremor is getting gradually back again


Update 28/12 – 07:05 UTC
- After some really turbulent harmonic tremor in between 05:00 and 06:00, harmonic tremor came almost to a halt. We do think that the eruption subsided a lot the last several days but that the current decrease has to be linked to a vent collapse. If this is the case the harmonic tremor will gradually pick up gain as the magma finds his way out.

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NOTE AVCAN 401 - EARTHQUAKE ACTIVITY-VOLCANIC - HIERRO ISLAND - DECEMBER 28 2011-10:30 h peninsular - seismic-volcanic activity continues to moderate, localized seismicity in el Golfo and Mar de las Calmas and some weak events detected. Continued volcanic tremor signal important in Restinga area, still strong until between 5:00 and 6:00 madrugaga has been made to hydromagmatic stronger explosions, 3 or 4, by interaction with water which have had to change the morphology of the outlet duct, or open another mouth, cleared completely, and making it flow smoothly, which has led to the fall of the tremor. After an hour with low tremor, has been again giving small cyclic explosions, the so-called Drumbeats .. these if they are .. with very short bursts at a mean time interval (such as half a minute or so). As for earthquakes, the magnitude was between 1.8 and 0.8. New earthquakes 3. Depth at 9, 12 and 21km. Days ago 1. Yesterday 2. Today they 1. A total of 11,950 earthquakes are located in El Hierro by IGN from 9:00 am of July 19, 2011.

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A personal opinion: I have the impression that the submarine volcano has released the final raspberry after a long deposition.
What I say of raspberry crackling under final.

And here's a theory that has upset the balance water-magma-pressure gases and it has penetrated the fissure running fast to cause evaporation and the resulting "bloat" as volcanic farts.

The result would be the crystallization of magma near the crack sealing and practice the same, preventing movements "peristaltic" of magma that no longer runs and therefore the tremor.

However, the digestion is not over ... would expect an increase in bowel sounds in the form of seismicity, and who knows ...

Turns out, the specific heat of water is 4 times greater than that of basaltic magma in mass, although the basalt is three times denser than water, the water still has greater cooling capacity comparing volumes. Therefore, it may have been broken as well preventing thermal equilibrium crystallization of basalt. But ... does not mean that the magma continues to have no end pressure ... simply does not flow as before because the water cools more quickly the volume of magma produced than before ...

That pressure, residual, could still have enough force to cause the opening of a crack after an event after shooting? Is it in the salty sea or land would be where the magma cools both the lack of water?
Counter-theory and opinions are welcome, the discussion comes the light.
(JR)
[bron]