El Hierro

[jand]

jonfr.com/volcano

Somebody in ER asked me whether the current pattern of bursts is a coincidense.
 This was my answer : Dear David, It does not have to be a coincidence. Look at it as a constantly heated cooking pan. If the fire underneath remains the same, the cover will regularly blow off some steam. The same is the case here. The vent is feeded with new material / gases (from the deeper areas in the El Golfo area) and when the pressure gets higher than the water column, it blows off. As we had only 2 volcanic earthquakes today and a more or less harmonic tremor, the process is not too much altered (like it was the case many times before). When the stain was seen at first (around October 10) a similar process had started. Very few earthquakes with a growing colorful stain. So, the main reason why there are so few earthquakes today, is that multiple vents have been opened (see the pictures from yesterday), and that a lot of material is erupted. If the process follows the same pattern than during the October 10 phase, more action is expected. Unfortunately bad news for the fish and for the people of La Restinga.
 Of course your opinion is highly appreciated


Armand Vervaeck says:

 November 24, 2011 at 14:35


I know that this is only one of the many scenarios. Do you guys and girls have another version here. Maybe 1 remark : on the webcams we see nothing at all, Ian and Joke who made pictures yesterday have seen only limited coloring and vent action. If you then campare yesterdays Guardia Civil pictures with those from Joke and Ian, this shows a way of difference. To conclude : i think we have a lot of action today but those bl... webcams are not showing it.

Reply


Carl le Strange says:

 November 24, 2011 at 16:19

My take is that this might be the final blow of Bob, and that the tube will shut down soon in a systemic collaps. Afters that Bob may, or may not, erupt closer to the harbour, in the harbour or onland.
 But, the current reports of sulphuric smell at Frontera tells an alternate story, a story that is corroborated by a lot of circumstantial evidence and an official report from one of the organisations stating that the most likely thing to happen now is an eruption happening on the line from Tanganasoga to Los Llanillos.
 I made a mini-post comment yesterday about this after reading the internal report of the organisation in question.

Reply


Armand Vervaeck says:

 November 24, 2011 at 19:14

I did read it Carl – indeed a viable scenario even more when i saw Geolurkings deformation image and on top todays smeel at Frontera . I am really curious what wil happen with the earthquakes when the current La Restinga vents are closing ! Ian was in Frontera today, will ask him whether he smelled it too

Reply

[jand]

jonfr.com/volcano

Una Canaria says:

 November 24, 2011 at 17:44


I would like to contribute information that may be curious and interesting. I've been looking for the status of one of the many caves of the Iron, and I have found one in particular caught my attention. This is the spit of Las Palomas and here's their description:
 "Pit of Las Palomas
 Location: El Golfo (Frontera)
 Depth:90 meters
 Description: This is an amazing and frighting cave located in the slope of the Tanganasoga volcano. Its entrance, whose vertical diameter forms a desdending slope of 45 per cent,gives away to a small oven from which three overlying tubes go in the same direction and with the same declivity as that of the slope. The lower tube can reach heights of 15 meters. This is one of the deepest volcanic pits of the archipelago and in its birth the typical mechanism o lava tube formation was merged with the latter melting of the overlaying tubes".
 Could Bob used again this volcanic tube to exit to the surface? The path is already made.

Reply

[jand]

jonfr.com/volcano

Ursula says:

November 24, 2011 at 18:24

For Lurking, Karen, Peter and shteve, here's my first rudimetnary take on 3D GIS layering:
 geology map on top (or bottom) of depth scatterplot.

Took me longer than I thought, mosltly because it turned out that the geology map (linked from Bob's page) is in a non-standard projected coordinate system (REGCAN 95), which none of my softwares recognised. So this required a bit of imaginative georeferencing via grabbing images in Google Earth and mapping the two together to link the geology map into the lon/lat UTM WGS1984 (in which earthquake data come). Of course, you think something like this would be easy and then look up after you're done only to find out that you spent a couple of hours data wrangling...

Anyway, before I get to be too technical, here's the view from top, Novemeber quakes, colour = magnitude, map on the bottom, as you can see it had to be warped into N-S, E-W direction:
 http://i40.tinypic.com/1z3un82.png

View from SW (different colour scheme for quakes, still showing magnitude, map on top):
 http://i44.tinypic.com/34q9pps.png

View from SE:
 http://i43.tinypic.com/hrxa81.png

View from NW:
 http://i39.tinypic.com/727tzm.png

[fifi]

Thanks for the updates jand. Its very interesting to read about the deformation near  the Tanganasoga volcano. Perhaps it is storing up energy and will erupt on land?

            ..............

Twitter


# ElHierro
The earthquakes at shallower depths, one at 10 km, the closest to the surface so far. It appears that the magma rises

 Had rash on or near the port would Restinga hydromagmatic explosion of several hundred meters. ( I presume it means if the rash had been ..etc)

Southern volcano loses pressure, tremor begins to have outbursts, there may be an accidental entry of water into the system

[jand]

Fifi I think this has been the worry all along about the rift and line of earthquakes following the path through to Tanganasoga because if this does blow then I am sure it has been mentioned before that this may cause the landslide everyone is worried about.

The co2 emissions have gone up 400 times today there is a graph to show this that has been put on teh Avcan FB page.

[fifi]

Yes I think so too jand. Im just trying to catch up now with whats happening.

Twitter

Seismicity has declined, IGN says maximum expected is 4.5 degrees

            ............

The Cabildo dont seem too worried about the deformation

(Twitter)
The deformation of the horizontal and vertical ground is stable.

[jand]

1114666

24/11/2011

20:54:43

27.7655

-18.0467

16

Sentido

2.8

mbLg

W FRONTERA.IHI

[jand]

Copied from Avcan FB
Al Pevolca le ha faltado decir que como ya "no hay sismos", y todo esta normal, demasiado normal diria yo, pues eso, que nos relajemos que aqui ya no va a pasar nada mas. Ya tenemos otro de 2.0 en la misma costa de Frontera y a 16 kilometros de profundidad. La cosa sigue, y las señales de que habra una erupcion en el norte se mantienen. Porque en vez de ocultar datos y aparentar que no pasa nada, se le informa a la gente para que este preparada por lo que pueda llegar??? Que no somos niños, que sabemos estar alerta pero que no nos engañen. Ya esta bien.


The Pevolca it has lacked to say that I like because "there are no earthquakes," and this normal, too normal I would say, because that, that we relax that here already not going to happen nothing more. We already have another 2.0 along the same border and 16 kilometres from depth. The thing is, and signals of that there will be an eruption in the North remain. Because instead of hide data and pretend that nothing happens, please be advised the people to which this prepared by what they can get? We are not children, we know to be alert but us not fooled. Now okay. (Translated by Bing)

10 minutes ago · Like

[jand]

http://www.elblogoferoz.com/

Although new data from the emission of gases in El Hierro island building will now be known, increases more than notable of helium and CO2, as well as the seismic swarm in the sea of the Llanillos aim at eruptive stage in the North of the island. To this it must add the data of deformation, which indicate an increase or inflation in the zone between Sabinosa and the border, where growth in these last three days is 1 millimeter daily, as they reflect the charts of the National Geographic Institute.
The direction of the PEVOLCA, however, in his usual communication noted that, with regard to the deformation of the ground, the processing of the data results the horizontal components of the strain to follow the same pattern of stability than in previous days. Vertically, all stations installed in El Hierro show deflation, with the exception of the of the Gulf which mostly point to a slight elevation.
According to the Pevolca, the tremor signal maintained a slight decrease continuously throughout the day, with emergence of pulses of very occasionally. In the analysis of the data do not appear evidence of a second source of tremor in the North.
However, yesterday and up nine o'clock in the evening, there had been 27 earthquakes, concentrated mainly in the North of the island, in the Gulf area, and markedly in the vicinity of the inhabited nucleus of Los Llanillos on the slopes of the Tanganasoga. Precisely in this place is where there has been by INVOLCAN an anomaly in the emission of gases that are kept in time and worries about the location, concern which is also endorsed by the values from the station located on the volcano, that recorded since a week ago worrying values.

[SurfJames]

This photo shows just how vulnerable those villages are from a landslide in the El Golfo region.



I'm not convinced that the vents are closing in the Restinga region; if anything there appears to be more of them. But, if they do collapse and others open, it will be interesting to see which direction the new vents appear. It could be closer to the harbour, as the fault line suggested from the earthquake swarms run in a N/S direction. There were clear bursts of gases closer to the harbour entrance today.

Also, worrying that the earthquakes appear to be getting closer to the surface (10 kms!) The magma could be rising up through existing lava tubes in the north. This would account for the smell of hydrogen sulphide in that region, and the positive deformation of the land.

[fifi]

It is a heavily populated area Surfjames. La Restinga has only a tiny population compared to it. I was looking at the GPS graphs and the only two showing a slight increase in deformation are H103 and H104. http://www.ign.es/ign/resources/volcanologia/html/deformacion.html

[jand]

canarias7.es

Translated


A tsunami in Spain would cause one catastrophe greater than the occurred in Indonesia in 2004

A tsunami in Spain would cause one catastrophe greater than the occurred in Indonesia in 2004, as they have alerted international researchers in Santander, at the same time that specified that areas of Cadiz, Almeria, Murcia or the Balearic Islands could be flooded with more than three meters wave heights.

Thus the researcher of the environmental hydraulics Institute at the University of Cantabria (IH Cantabria) - framed in the area of excellence for energy and water of Cantabria Campus international - Mauricio González, has warned of this possibility in a press conference, which has also brought the Coordinator of the Group's instrumentation to detect tsunamis of Puertos del EstadoBegoña Pérez.

Both complained that Spain has not developed its early warning system, which means that when one alert of tsunami "it won't react to know", and these alerts will start arriving next year when other countries implement their systems.

Therefore expressed that a closer involvement of the Government of Spain, need first to be appointed an institution to develop the system, and second to provide funding that allows carrying it out.

A total of 80 researchers from 40 countries met until Thursday at the Institute of environmental hydraulics, Universidad de Cantabria # IH Cantabria # at the annual meeting of the Intergovernmental Working Group for the development of an early warning system for tsunamis in the Eastern Atlantic, the Mediterranean and adjacent seas # IOC/NEAMTWS # UNESCO.

This meeting was held for the first time in Spain just to try to alert the Government of the risk of Spain if a tsunami near the case and is not counted with an early warning system, and therefore an action Protocol, to detect where will, when and with what magnitude.

"High risk"

All European countries have already almost to point their local early warning systems, to be complemented by the European system, while in Spain has not advanced to the Spanish coast have "high risk" of suffering tsunami, indicated González.

Pérez has pointed out that you one of the elements "more important" for this system is "the instrumentalization at sea", i.e. the placement of tsunami detection systems. All gauges have been renovated in Spain, after the tsunami that arrived to the Balearic Islands in 2003 after the earthquake happened in Algeria.

However, this is not enough. On the scientific side "is done", emphasised González, have adapted the gauges for the detection of these tsunamis, small or large, and also development of numerical models and automatic algorithms to detect these phenomena in real time.

"Lack of political will"

"Which lack makes is political will to develop early warning system," insisted González, because Spain has a riesgo "important" the arrival of tsunami and "can come in 100 years or tomorrow".

In addition, this researcher has placed particular emphasis on that "there is no natural disasters, what exists is a mismanagement of natural phenomena".

Therefore, tsunami experts call the Government of Spain awareness of the need to create this early warning system with emergency protocols and programmes of preparation for the population, because "if tomorrow comes a tsunami will not know to do", has praised Gonzalez.
At the press conference have also been present the general coordinator of ocean IGC, François Schindele; and the regional director for the national service of meteorology of the United States, Bill Proenza.

[jand]

canarias7.es

Pues precisamento hoy me he enterado de que en la isla de La Palma puede llegar a haber un corrimiento de tierra en un volcán, y que tal desprendimiento hacia el mar ocasionaría olas de 20 metros que llegarían a la costa este de Ameríca. Buscad en youtube y confirmad...
24.11.2011 17:37

Translated

Therefore precisamento today I've heard that on the island of La Palma can be a landslide in a volcano, and that such detachment towards the sea would cause waves 20 meters which would come to the East coast of America. Seek in youtube and confirmad...
24.11.2011 17:37

[SurfJames]

quote:Originally posted by fifi

It is a heavily populated area Surfjames. La Restinga has only a tiny population compared to it. I was looking at the GPS graphs and the only two showing a slight increase in deformation are H103 and H104. http://www.ign.es/ign/resources/volcanologia/html/deformacion.html

Yes - agreed fifi. The deformation is tiny and could be an anomoly such as experimental error, due to the equipment heating and expanding in the sun. It's a matter of 2-3 mm I believe. But the localisation of earthquake swarms and residents expressing concern about sulphurous smells suggest otherwise.

[jand]

http://www.uclm.es/profesorado/egcardenas/SISMICIDAD_VOLCANICA[1].pdf

This looks interesting but needs to be translated.

http://www.uclm.es/profesorado/egcardenas/SISMICIDAD_VOLCANICA[1].pdf

[fifi]

You suggested the need for an early warning system for Tsunamis a long time ago jand. Isnt it interesting to see how they are suddenly thinking along those lines now that it looks like the eruption may be on land?

[fifi]

quote:Originally posted by SurfJames

quote:Originally posted by fifi

It is a heavily populated area Surfjames. La Restinga has only a tiny population compared to it. I was looking at the GPS graphs and the only two showing a slight increase in deformation are H103 and H104. http://www.ign.es/ign/resources/volcanologia/html/deformacion.html

Yes - agreed fifi. The deformation is tiny and could be an anomoly such as experimental error, due to the equipment heating and expanding in the sun. It's a matter of 2-3 mm I believe. But the localisation of earthquake swarms and residents expressing concern about sulphurous smells suggest otherwise.

True, the graphs have been wrong before. The smell is probably a better indication of what and where things are happening.

[SurfJames]

A quick recap for newbys:

The Canary Islands sit on the edge of the African Plate.

Under these Islands lies an area of magma which is able to break through to the surface when the African plate shifts. It is to this that the islands owe their very existence.

Most of the islands are still volcanically active and there has been speculation that a smaller, previously undetected fault line also runs through the chain.

El Hierro - which means 'iron' in Spanish - was formed after three volcanic eruptions 100 million years ago and is topped by a volcano more than 6,000ft high.

Volcanic activity - mainly where three ridge lines converge - has caused El Hierro to expand continually. The last time it erupted was in 1793.

[jand]

Fifi my worst fear when all this started weeks ago from my first posts was a threat of a Tsunami not just from a landslide I also thought just a small earthquake on the seabed could trigger something.

If people would only just have realised I was trying to be practical and I still remember the proffesors words to me when I spoke to her from Durham University that she did not think I was talking crazy she thought I was being sensible and practical and she was listening to what I was saying.

All I know is that IF whatever happens in El Hierro causes a Tsunami we have 45 mins before it will reach Fuerteventura.

[SurfJames]

quote:Originally posted by jand

Fifi my worst fear when all this started weeks ago from my first posts was a threat of a Tsunami not just from a landslide I also thought just a small earthquake on the seabed could trigger something.

If people would only just have realised I was trying to be practical and I still remember the proffesors words to me when I spoke to her from Durham University that she did not think I was talking crazy she thought I was being sensible and practical and she was listening to what I was saying.


All I know is that IF whatever happens in El Hierro causes a Tsunami we have 45 mins before it will reach Fuerteventura.

Jand...In order to create a tsunami, you would need an earthquake far more powerful than those caused by lava rising through faults and lava tubes. That's why the quakes are mostly low level, and rarely above 4.

The only way you could get a big enough quake, is from a tectonic plate shift, and experts have stated that this is extremely unlikely. Infact, the probabilty is almost zero.

To be perfectly frank, you have a greater chance of being run over or being eaten by a shark, so don't worry and sleep soundly. []

These are not earthquakes, in the true sense with respect to their description. []

[fifi]

When you look at all the large landslides that El Hierro has already had in the past though Surfjames which are supposed to have caused Tsunamis, it does make you wonder. If it has happened before, could it not happen again? Volcanologists have said that local Tsunamis of up to 50 metres have been proven. The truth is ....no one really knows. I can understand your concerns totally jand.

"Luis Ignacio Gonzalez de Vallejo, Professor of Geological Engineering from the Universidad Complutense de Madrid said that in the Canary Islands there have been waves of up to 50 meters created by large landslides" (Source La Vanguardia)

[jand]

http://oi40.tinypic.com/k9hsmt.jpg

[jand]

Copied from Avcan FB

Translated

In relation to the new emission of gases: "these observations confirm the existence of pulses or sudden discharge of gases by underwater eruptive activity south of la Restinga disappear later but which are of a great utility to detect and locate new sources of emission or eruptive mouths associated to this volcanic process." The geographical coordinates of this new sudden discharge of gases has been North 27th 607547 - West - 17º 991288. This pulse of gas is a highly significant phenomenon, according to experts, energy values it is comparable to the size that could be observed in the artwork offered to an earthquake of magnitude 5. This means that if many of these phenomena would discharge much of the pressure of magma into the underwater pipe, which would favour one less scenario
 "dangerous in the case of a new eruption and perhaps seismicity who registers before it." (Translated by Bing)

[fifi]

Originally posted by jand

http://oi40.tinypic.com/k9hsmt.jpg


http://i44.tinypic.com/50pj04.jpg

Who produced this deformation image do you know jand?

[TripleH]

Goodnight everyone. Sleep well

[SurfJames]

quote:Originally posted by TripleH

Goodnight everyone. Sleep well

Nighty night Tiple.....[]

[fifi]

And nearly goodnight from me.[]

This is really interesting if anyone has the time to read it. It describes the formation of all the Islands and also mentions that Fuerteventura and Lanzarote and some other Islets were joined together at one stage. See page 27 to 29. Page 42 discusses what causes the landslides and is worth reading.

Edited out for a minute to see if the link is causing the page to spread

Page 43

Page 44 describes a mega Tsunami caused by El Hierro which reached the Bahamas and is worth reading too.

[caletillas]

Well, just back from a month in Fuerte and no one is really paying much attention to El Hierro (despite Danny trying to put the wind up me about the freak high tides at the end of Oct!)

[fifi]

Welcome back Cal. Hope you had a nice time. We are still at it here as you can see.[]

[caletillas]

quote:Originally posted by jand

canarias7.es

Translated


A tsunami in Spain would cause one catastrophe greater than the occurred in Indonesia in 2004

A tsunami in Spain would cause one catastrophe greater than the occurred in Indonesia in 2004, as they have alerted international researchers in Santander, at the same time that specified that areas of Cadiz, Almeria, Murcia or the Balearic Islands could be flooded with more than three meters wave heights.

Of course this tsunami threat to the peninsula is nothing to do with vulcanism in the Canaries. The threat comes both from the Straits of Gibraltar fault line (a magnitude 8+ submarine earthquake on this fault on 1 Nov 1755 caused the 50 foot high tsunami that destroyed Lisbon, the entire Algarve coast (wave height 100' at Faro) and caused massive destruction in Morocco and on the Spanish Atlantic coast, with 12' tsunami waves even reaching western Cornwall and Galway) and also from fault lines and vulcanism further east in the Mediterranean. Both seaquakes and major volcanic eruptions have triggered large tsunamis in the Med in the past:-

The deadliest tsunami in the Mediterranean occurred in 365 when, following an earthquake near Crete, a tsunami wave devastated the southern and eastern coasts of the Mediterranean, particularly Libya, Alexandria and the Nile Delta, killing thousands. Others hit Crete, Syria and Israel in 1303, Greece in 1650 (50' tsuamis hit Crete) Sicily in 1693, Calabria-Italy in 1783 and Messina-Sicily in 1908 (40' waves destroyed Messina and killed 70,000+.)

The most recent tsunami-triggering earthquakes in the Med region are those of Izmit, Boumerdes and Aigion in the Aegean sea. On 31 December 1995 a 10' high tsunami inundated coastal areas along the southern shore of the Gulf of Corinth in Greece. In 2003 after a submarine landslide caused by the Boumerdes earthquake in Algeria, tsunami waves up to 7' high reached the Balearic Islands causing no injuries.

Tsunamis generated by volcanic processes are a considerable threat to coastal areas around the Aegean and Tyrrhenian Seas. On 30 December 2002, a major instability occurred on the Sciara del Fuoco slope, on the western flank of the volcanic Stromboli island. The tsunami induced by the landslide spread around the island and the surrounding Aeolian archipelago and was felt as far away as the coast of Sicily.

Tsunami events occur also in areas of no or weak seismic/volcanic activity and are related to instabilities of sediments deposited on the shelf or the slope off large river mouths. The most striking example took place on 16 October 1979 in the western Mediterranean. A large slide occurred in shallow water during operations related to the enlargement of Nice airport at the Var River mouth. The tsunami, which followed the collapse, drowned the coastal zone of Nice and several people were killed.

In other words, you stand a much greater chance of being caught up in a tsunami virtually anywhere in the Med, where there is a catostrophic tsunami every hundred years, than you do in the Canaries, where there have only been 3 recorded events since Spanish settlement.