El Hierro

[jand]

Looks like the sea churning up on the panoramic webcam?

http://212.170.244.196/

[jand]

Something is definately happening sea going backwards ?

[jand]

The sea is being sucked backwards dark stains?

[jand]

Even in the calm area where the boat is the sea is also being sucked backwards ?

[jand]

Glowing white stain in the harbour?

[jand]

jonfr.com/volcano

Lurking says:

 November 21, 2011 at 18:11

The island of El Hierro sits atop of Jurassic era sediments.

Back when the Atlantic ocean was initially opening up, it went through a stage of development not too different than the current Rift Valley of Africa. As the crust thinned from being drawn apart, it lowered in elevation and formed a basin which then collected sediment from normal erosion in the area. As the sediment thickened, it began compressing at it's lower extents... eventually becoming shale.

Later, when the Canary hotspot poked a few holes in it and made the islands, it did so on top of this sedimentary basement.

Shale, though a rock, is not extremely strong. It has a pretty low tolerance to stress and can easily slide/ooze. Unlike the Central US, the shale under El Hierro has remained under a rather large blanket of water ever since the Atlantic has covered the area. This allows the pore pressure to remain quite high, and assists in lubricating any movement.

As the volcanoes developed, some of the sedimentary material, mainly the shale, has been able to undergo metamorphosis due to the hight pressure and heat. Given the pressures involved, the likely products range from slate to phyllite and schist, with phyllite being the most likely product given the depths.

Phyllite has a bending strength of about 48.6 MPa and is in an environment of 400 to 500 MPa. Essentially that means that when pushed, it will ooze. Everything else in the strata is going to be least resistive since Phyllite is the most advanced product that is likely, and the hardest and densest.

Quakes will only occur if the dynamic load that is placed on the material exceeds it's ability to bend or deform to comply with the stress.

And, that's about the best explanation I can give you... other than the very real possibility that the entirety of the island is made up of old tubes and pathways from previous activity, and it probably doesn't need a lot of new fracturing to find a path to the surface (subsea for now).

[jand]

http://www.ign.es/ign/layoutIn/volcaDetalleTerremotos.do?evid=1113859&zona=2

[jand]

earthquake-report.com

Ian Carson reports :
 I went to Restinga for 0830, everything was quiet and the tremor intensity looked to be decreasing (on my phone) so I caught the bus at 10.30 to return to El pinar. On leaving Restinga and beginning the 900 m climb to Pinar, it was clear that something was stirring on the sea. The locals were all aware of it. I summoned the driver to stop (immediately) as I had been waiting for 3 days for any evidence of activity. Luckily, I was at the closest point to the activity, probably 1.5km nearer than the webcam. The 'Jacuzzi' was clearly evident as it was cloudy thus eliminating the normal blue reflection of the sky and increasing the contrast of the 'Jacuzzi'. In a short time, the Civil guard helicopter was in the air with geologists aboard. One of whom I was later to have a long discussion, he spoke good English and freely gave his time. The friendliness of the Canarian people has been a memorable part of this trip. I must also thank the 'Cafe Melao' who freely allow me to use their wifi after purchasing the occasional cup of coffee.

http://www.youtube.com/watch?v=7aUDwBzIUmE

[jand]

https://picasaweb.google.com/110327184570944806725/ElHierroNovember21201#

[jand]

Have checked the tides for today for El Hierro dont think they had anything to do with the sea going backwards this evening.


Today Monday, 21th of November of 2011, the sun rose in Puerto de la Estaca (El Hierro) at 7:38 h and sunset was at 18:17 h. The moon rose in the east (96º) at 3:21 h and set in the west (261º) at 15:17 h.

In the high tide and low tide chart, we can see that the first low tide was at 3:09 h and the next low tide at 15:43 h. The first high tide was at 9:24 h and the next high tide will be at 22:01 h.

Maybe it was something to do with the 3.3 quake at 1805?

[jand]

http://www.ign.es/ign/layoutIn/volcaDetalleTerremotos.do?evid=1113862&zona=2

At 1920 a 2.4 earthquake SW El Pinar on land and it was only 15km deep.

[jand]

Alyson says:

 November 21, 2011 at 21:19


I don't know enough about volcanoes to have an informed enough idea about what is going to happen with El Hierro. Eyaf started small and picturesque, then grew steadily and mostly from a distance. Merapi was shocking in the scale of the impact on the local population – and in the organisation of the military when they were trying to evacuate people from cold lahars and pyroclastic flows. The logistics of moving a lot of people in rapidly escalating risk was difficult to comprehend, given the scale of the erution.

El Hierro is different. It is very steep, and yet seems to have been bigger in the past. It has 'bites' taken out of it, and trying to envisage what was there before, and how it might relate to what is there now, is a challenge. The promonteries appear to be growing with extensions of lava from vents below the water level. Lava tubes are hollow, and so would seem to be gas tubes.

I cannot currently find the paper that suggested El Golfo sheared before the main eruption 250,000 years ago, but if that is a precedent, then how might it relate to what is happening now? There are under-sea vents on the ends of all 3 points of the island, mostly degassing, with occasional magma bombs. The hot magma originates from a hot spot far below the island, yet the quaking is located along a rift.

It exerts a fascination because it is not fully understood. It may go on like this for years or it may do something we don't yet have the understanding to predict.

[jand]

Important Update 21/11 – 21:13
- At 18:02 tonight a 3.3 magnitude earthquake struck at a depth of 21 km in the El Golfo area, the location where almost all the earthquakes are occurring.
 - another earthquake attracted our attention. The M 2.4 earthquake at a depth of 15 km with an epicenter below the coast of Puerto Naos.

Important Update 21/11 – 18:06
In a twitter message tonight, PEVOLCA and IGN have dismissed that todays activity would be a new vent. IGN and GES scientists made a flight this evening by helicopter.  The information from Ian Carson came from the helicopter flight of the Guardia Civil which took off when the activity was at his strongest, which cannot be said from the IGN / GES flight !

[Florence]

So, the small volcanic activity on El Hierra has caused earthquakes on the Azores and Madeira now... I give up.  And as for the sea going backwards?
Hoping for a tsunami are we jand?  Still awaiting something big to happen on La Palma and for a vent to open up on that mountain in El Hierro that
people are using to get a good view of the "underwater eruption".

I am glad that some of you have found the information given by someone, who clearly hasn't got a clue, is beneficial.  For me, I would rather
stick to the facts.

[TripleH]

quote:Originally posted by Florence

So, the small volcanic activity on El Hierra has caused earthquakes on the Azores and Madeira now... I give up.  And as for the sea going backwards?
Hoping for a tsunami are we jand?  Still awaiting something big to happen on La Palma and for a vent to open up on that mountain in El Hierro that
people are using to get a good view of the "underwater eruption".

I am glad that some of you have found the information given by someone, who clearly hasn't got a clue, is beneficial.  For me, I would rather
stick to the facts.

Maybe Florence but you haven't stacked up 700 posts on one thread have you?

[IsThisForumStillGoingWow]

700 posts by jand now, only 6 before the volcano thing...694 posts on this thread alone....mostly one after the other after other after the other....

[jand]

The eruptive fissure is progressing and the tunnel cracks

Geologist, specialist in volcanology. Author of 54 maps geological scale 1: 25,000 from the rainstorm national map of the Canary Islands, among which are those of the island of El Hierro


José Luis Barrera Morate

Translated

21 November, 2011 by José Luis Barrera Morate | 4 Comment

Since that occurred the underwater eruption the last day of October 10, all to think that the crisis would come to an end within a few days. But it wasn't like that. We have 40 days of eruption and don't know when this ends. In the North of the island in the Gulf, began a new seismic crisi with most profound hipocentros and somewhat higher magnitudes. Also the direction of the new fissure is different: points to La Restinga directly. If it progresses on land, the danger increases and thus the risk.

The risk is not whether there will be rash or not. The State of the Roquillos tunnel is worrying. Last day of October 18, technical auscultaron it and discovered many shortcomings caused by earthquakes: cracks in several sections, wires with detached anchors, deprendimientos in the key; in other words, the current state is dire. With popular pressure, who's who now dares to say that it is dangerous to move by him while continuing earthquakes, some of magnitude 4.0?

Another day tell them about the Rooster tails.

[jand]

http://www.quo.es/ciencia/naturaleza/el_volcan_de_el_hierro

Translated

Gabriel García Márquez, one hundred years of solitude, described José Arcadio Buendía as "the protomacho whose volcanic breathing was perceived throughout the House". He meant by his powerful girth and the energetic and adventurer of his character. With volcanoes occurs equally: to decipher their wild mark must observe its "breathing", i.e., the gas that emits materials that eject, the frequency with which does it, the tremor in the flow of lava under its "lungs" of rock.

But, just as one doesn't known completely to the Gabo character in the novel, the scientists never get to know at all what he is thinking the Earth, in the volcano of El Hierro and others. The writer is almost exceeded in the details of the origin and birth of José Arcadio, but the mechanism of formation and behavior of volcanoes, and especially sailors, does not have so many tracks.

And perhaps it is because they have a special feature: that the magma causing them - them and the volcanic islands such as iron - can be a direct "shipment" from the very outer core of the Earth, to 3,000 km deep. And what else might come? Only 33 km beneath our feet, as a maximum. It is superficial magma, which always is more likely to go out because it is the result of the friction (by subduction or section) or collision between two plates, an Oceanic and other continental; or between two of the same type.

Magma from the 'floor'
It is important that both types of magma are different, and whether its origin is one or another would bring news of the future and the past. I would say to the inhabitants of the island if the succeeding eruptions can be more or less explosive; and geologists them would talk about a million years ago, when he began to form El Hierro.

For this reason, various Spanish and international universities are considering remnants of lava that swim. Seeing the amount of gas in the white part of these "cocos" magma (trachyte), the Faculty of geology at the University of Barcelona said that eruptions could be still more explosive than thought initially.

The trachyte is a type of rock as always under the bark. But Joan Martí, of the Institute of Sciences of the Earth Jaume Almera, subsidiary of CSIC, believed by telephone from El Hierro which is exaggerated to speak of dangerousness and explains to Quo very clearly: that white portion "has a content in volatile of the order of 4 or 5%, a temperature of 850 ° C and a density of 2300 kg/m3, making it more explosive", but only represents 10% of the total mixture. Because 90% remaining (the black part) is basalt, that counts with "only 2% of volatile, a temperature of 1,200 ° C and a density of 2700 kg/m3", something which greatly reduces the virulence of these volcanic eruptions.

So El Hierro geologists know something: most of the magma is basaltic, and that means that it comes from the deeper layers of the Earth. The mechanism by which that magma has been able to ascend from the outer core is exciting. Discovered it in 2005 Sebastian Rost and Edward Garnero (Arizona State University), and Quentin Williams and Michael Manga (California). These geologists and volcanologists found that rushing chimneys of the Hawaiian volcanoes are assorted by what they called "roots", through which amount different feathers of magma (named for its shape of Wick) from 3,000 km further down. And this could explain why many volcanic islands have a very steady activity.

Journey to the center of the Earth
The trip follows very easily if we we submerged in the outer core of the Earth. There the rock is melted (say to liquid), but the next layer, the mantle, is almost solid. At certain points of the boundary between both layers there is a huge bubble of partially molten material which act in mouth of output. And why to climb toward the mantle rock not solidifies as the rest?

Because seems to be that (this roughly) about these magma feathers form a crystalline "walls" that preserve and "Guide" material to the cortex. "Could be under the volcanoes of Hawaii and Iceland would have such an asset bubble," explained Rost to submit the finding published in Nature.

The crux of the matter is that, although the mantle is almost solid, does not mean that it is still, but there it convection currents because it has a behaviour that Geophysicists call plastic. Such flows, as it supports modern geology, would be responsible for the movement of the plates of the Earth's surface. Hence the curious: If these variations are what shocks and frictions between them and, therefore, places where there are eruptions are unpredictable, why do some areas (especially Islands) where volcanic activity is continuing?

[SurfJames]

This is fascinating stuff jand........I love it and have learnt so much about volcanos and how they form etc.

I learnt recently that Teide is the 4th largest in the World!

Ignore the derampers - I guess they find intellectual pursuits a bit threatening or something.[][][][8D]

[jand]

SurfJames

I agree that this is so fascinating and I also am learning different things day by day and its so intersting to read the comments I post from other people on their own factual opinion whats happening aswell.

Have come to the conclusion I have a few deramper stalkers one of them especially Florence has a rant she twists my words and sometimes makes up things I never have posted or said.

Florence Quote So, the small volcanic activity on El Hierra has caused earthquakes on the Azores and Madeira now... I give up

Florence once again needs to get her facts right I never said or stated that El Hierro caused the earthquakes on the Azores or Maderia copied below is what I posted

There have been two earthquakes near Maderia this afternoon one a 5.00 and one a 4.1 within two minutes of each other.

ESMC.

2011-11-20 14:31:12.4 32.23 N 19.98 W 10 mb 5.0 M. MADEIRA ISLANDS, PORTUGAL REGION MAD
2011-11-20 14:31:10.0 32.03 N 20.43 W 82 ML 4.1 M MADEIRA ISLANDS, PORTUGAL REGION IMP

Avcan Comment Re Earthquake 5.00 Maderia.

An earthquake of 5 and although it is not about, can it causes some effect, to the more causing the same that if missed more firewood to the fire, a small revival of both systems in the North and South, of which only can be expected since the tremor is quite high.(Henry).


http://www.01.ign.es/ign/resources/sismologia/www/dir_images_terremotos/detalle/1113579.gif

--------------------------------------------------------------------------------
Edited by - jand on 20 November 2011 17:59:01

[jand]

At 0352 this morning there has been a shallow quake at only 12km.

http://www.ign.es/ign/layoutIn/volcaDetalleTerremotos.do?evid=1113903&zona=2

1113903

22/11/2011

03:52:28

27.7495

-18.0503

 12

1.6

4

W FRONTERA.IHI

[jand]

jonfr.com/volcano

Copied

Irpsit-But this is the post on El Hierro and Katla is fairly quiet. This one has a lot of potential for human kills such as the islanders. Katla will go eventually and with a loud lead in to the main noise.

This one is fairly silent because of the type it is. It could enter the tube system under the island and exploit it literally within minutes. Thats not boring I dont think... At least to me.

It isnt a minor eruption underwater. No its an eruption field of about 3-5 football fields which is about the same as the mouth on St. Helens. It has multiple vents in that area right now and no one is sure whether its the main show or not.

Kind of crazy when you think about it.. .Most of the quakes are to the NW and the eruptive activity is about 40 miles SE. So, what is really happening there could affect the lives of everyone on this planet or nearly so. A flank failure and we get a tsunami, an eruption into the tube system or the tunnel and you are going to need a bunch of new Spaniards because it could happen very quickly.

Certainly not ho-hum to most of us.

[jand]

jonfr.com/volcano

Alyson says:

 November 21, 2011 at 21:19

I don't know enough about volcanoes to have an informed enough idea about what is going to happen with El Hierro. Eyaf started small and picturesque, then grew steadily and mostly from a distance. Merapi was shocking in the scale of the impact on the local population – and in the organisation of the military when they were trying to evacuate people from cold lahars and pyroclastic flows. The logistics of moving a lot of people in rapidly escalating risk was difficult to comprehend, given the scale of the erution.

El Hierro is different. It is very steep, and yet seems to have been bigger in the past. It has 'bites' taken out of it, and trying to envisage what was there before, and how it might relate to what is there now, is a challenge. The promonteries appear to be growing with extensions of lava from vents below the water level. Lava tubes are hollow, and so would seem to be gas tubes.

I cannot currently find the paper that suggested El Golfo sheared before the main eruption 250,000 years ago, but if that is a precedent, then how might it relate to what is happening now? There are under-sea vents on the ends of all 3 points of the island, mostly degassing, with occasional magma bombs. The hot magma originates from a hot spot far below the island, yet the quaking is located along a rift.

It exerts a fascination because it is not fully understood. It may go on like this for years or it may do something we don't yet have the understanding to predict.

[SurfJames]

jand.......

Don't worry. []

Keep following your passion and post what you find interesting.
This thread is being followed by a lot of people who don't actually post.
You have bought the forum alive! [][][][8D]

[SurfJames]

The jacuzzi is very clear this morning on the panoramica webcam,
but the closer cam position has been moved to the second jacuzzi and this
appears quiet.

The sea looks rough this morning.

[jand]

http://212.170.244.196/

On the panoramic webcam view can anybody else see what looks like a stain from the edge of the jetty into the port and trailing to the right out to see.

This is where yesterday evening I saw the darker ripples going backwards and the sea was churning up a lot.

[jand]

earthquake-report.com

Data update 22/11 – 09:18
 - More seismic activity today
 - Harmonic tremor subsided since yesterday 03:00 and has stabilized with occasional ups and downs since yesterday 18:00 UTC
 - The increased number of earthquakes are (so far) related to the subsided harmonic tremor. We expect the earthquakes to become gradually stronger again until we will have a new strong eruptive period. The buildup can last from a couple of hours to a couple of days.
 - 12 earthquakes M 1.5 or since midnight
 - Earthquakes are M 2.1 or less
 - Depth hypocenters : 12 to 23 km
 - The epicenter of the shallowest earthquake (one of the shallowest in the El Golfo area since the beginning of the activity) was almost below Los Llanillos. If there would be more of these, it will have to be seen as a major new step in the activity (no immediate danger but it will need careful examination)
 - the sea is too wild to see any stains or Jacuzzis this morning
 - – Weather forecast for today : the wind will be blowing from the North-East (current to the west). Max. wave height 2.0 meter. Sunny most of the day.
 - more weather prognosis at the El Hierro page of Windfinder.com

Update 22/11 – 09:10 – La Restinga Webcam saga (continued)
 We are very sorry that we have to write continuously about the webcams, but the authorities have not yet learned how to use the webcams properly. At the one hand they are proud that the world is looking to them, but on the other hand they do not take care and they don't keep their promises.
 - One of the biggest complaints of the La Restinga Eruption webcam is that is is constantly moved
 - When there is a reference, like the port wall, one can see clearly like this morning, that the focus is completely away from the stain and eruption vent.
 - The promise of the 2 webcams that Telefonica and the Cabildo should install in the north (El Golfo area) is not kept


--------------------------------------------------------------------------------

[jand]

http://www.mantleplumes.org/WebpagePDFs/Canary.pdf

Very interesting to read and has lots of photos maps and graphs  someone on another site says it sheds light on to some of the posts Lurking on jonfr.com/volcano has posted (I have previously posted some of them).

[jand]

Earthquake of 4.0 this morning in the Azore islands Region.

Magnitude ML 4.0
Region AZORES ISLANDS REGION
Date time 2011-11-22 08:44:57.0 UTC
Localização 36.89 N. 22.51 w
Profundidade 10 km
Distâncias 1099 km NW San cristóbal de la laguna (139.928 pop; Hora local 08:44:57.3 2011-11-22)
295 km E Ponta delgada (20.056 pop; Hora local 07:44:57.3 2011-11-22)
km 273 E Vila franca do campo (5.035 pop; Hora local 07:44:57.3 2011-11-22)

[jand]

Just learnt something new.

Copied from Avcan

Acabo de descubrir que entre Canarias y Madeira están las Islas Salvajes, que son de Portugal pero España no reconoce su soberanía. Sólo viven tres guardas pero son una importante reserva natural, gracias a su complicada orografía.

Translated.

I just discovered that between the Canary Islands and Madeira are the savage Islands, which are Portugal but Spain does not recognize its sovereignty. Only live three guards, but they are an important natural reserve, due to its complicated topography. (Translated by Bing)

10 hours ago · Like · 3