El Hierro

[pennylane]

looks like its bubbling up agaqin Fi

[SurfJames]

Wow - Have you noticed the pair of legs behind that lava bomb in your picture fifi? That stone is massive.

It's amazing that these structures float.. They must be full of gas bubbles between the igneous crystalline crystals.
Igneous rock is incredibly hard, due to the way the crystals interlock. These things must be like a crunchy bar inside. []

So we now have pure lava reaching the surface. Not long before the roosters start!!!!  [][][8D]

[pennylane]

I'd love to see this from the air. Did the helicopter post any pics from this morning ?

[jand]

26 noviembre, 2011
 por José Luis Barrera Morate

The eruption has already had its precedents

Seismic and volcanic crisis in El Hierro has its precedents in time geologically very nearby, and is recurring in the n-S corridor from the Gulf to the Julan. Therefore, it is not a new eruptive phenomenon in the volcanic history of the island.

The area occupied by the first preeruptive seismic crisis (from July 17 to October 10) completely matches an eruptive corridor that crosses the island in n-S direction, from the Gulf to the mar de las Calmas. The areas of initial epicenters were located on the coast of the Gulf, in front of Sabinosa, and on the high slopes of the Tanganasoga volcano, the largest volcanic edifice of the filling of the Gulf, and virtually on the island. The age alleged for this volcano is approximately 6,000 years, but its peak entered eruption for several times; the most striking was through a fissure of four aligned craters opened on its slope is. I was already pointed out that the active structural guideline was the n-S. Everything seemed to indicate that the Tanganasoga was reactivating. However, magma failed to ascend by the thick layer of materials and continued South towards seeking a way out. But there are still more. On the slopes of El Julan, and aligned with the Tanganasoga, there are a few small buildings Julan, the Garañones, postdeslizamiento which confirm the resurgence of volcanism deslizada once the slope of El Julan. But, the eruptive corridor was extended under the mar de las Calmas and, within it, there were underwater eruptions that are cartografiadas. In the end, the intersection of this wide eruptive corridor with an undersea fault caused the eruption on submerged ridge of La Restinga.

The next time that you have knowledge that a seismic crisis is reproduced in the area is in 1793. Since the end of March to July of that year, the seismic crisis was very intense. He also started in the area of Sabinosa, and then spread to all the Gulf. Some earthquakes lasted several seconds, as recounted it the inhabitants. In the month of June, there were some very violent it toppled homes in the Gulf and the capital, Valverde. Several ridges of the wall of the Gulf, destroying houses collapsed. Tremors of focused on Sabinosa, as always. Some authors, to this crisis of the 18th century, have suggested that there was an underwater eruption, while others claim that there was a basaltic eruption in the black area to the West of Sabinosa.

In short, the current eruption has already had its precedents in the eruptive corridor of the Tanganasoga, and the seismic crisis that has virtually completed in the Gulf, again confirm that this is the area of the island that has active for many years.

[pennylane]

jand, is that a way of playing down the current activity ?
If they are saying it's nothing new ! then why is there so much
interest and why is the current activity in the ocean visible now but not
before....
Forgive me if I've got this wrong but as you know I'm a novice at all this.

Glen

[jand]

Glen

I read this as not playing it down but explaining that this has happened before and this eruption seems to be following along the same direction as the eruptions before.

Maybe I am wrong?

[pennylane]

oh ok jand..I thought it was another quote to minimise what was happening !
That's me ever the cynic !

It's so interesting jand...I have it on the PC permanently and keep popping in  for a look lol

Ive already burnt the roast ha ha

[jand]

http://geocrusoe.blogspot.com/2009/02/tipos-de-actividade-vulcanica-submarina.html

Interesting .

Copied and translated.

Volcanic eruptions can occur with the top of your fireplace in Earth (lava) or at sea (submarine), the latter are less well observed, because much of its activity is below water level, so impossible to be seen directly by volcanologists.

The Azores two major volcanic eruptions of the 20th century stood at sea and the different depths, the last, located Northwest of the tip of Serreta da ilha Terceira, with evidence of activity since the end of 1998 until early 2000: the submarine volcano of Serreta.

Photos on this link shown below from year 2000 are identical to what has been posted this morning.

[jand]

[fifi]

I had a quick look for more photos and cant find any more official ones taken by the helicopter apart from a couple more of steaming stones and another one of another  volcanic bomb very similar to what is posted Glen.

[jand]

However, detected-if the occurrence of a phenomenon never described before by scientists: the projection from a certain depth, hot lava blocks, whose exterior solidificava, while the interior remained partially molten, these insuflavam to rise, emerging internally hollow spaces and with volcanic gases. These features reduced the overall density of blocks and made them floating temporarily. After the surface, these esfriavam, lost their gas in the form of white fumes, sometimes explodiam and, finally, were sinking-if such blocks
 are to be designated by lava balloons.

The name given by scientists to a type of volcanic activity is based on models of eruptions that have been well studied, described for the first time with great detail and with specific features.

So, having been the first scientific description of volcanic phenomenon, several Portuguese geologists have proposed that if pass the call on submarine eruptions, basaltic, relatively deep and where formed lava balloons as having ERUPTIVE ACTIVITY of SERRETIANO TYPE (Serretyan activity).

[pennylane]

That's interesting jand...

"with evidence of activity since the end of 1998 until early 2000: the submarine volcano of Serreta.
"


So this was over two years then but if these photos were from the year 2000, are there no other photos after that ?

Look what you've done now........I will have to go and research that now lol

Glen x

[jand]

Well done lads you put the powers that be to shame !!!

[pennylane]

Ok got it I'll now have to read up on it all night..x

http://www.sveurop.org/gb/articles/articles/Serreta.htm

[fifi]

The type of submarine eruption that is happening is called a Surtseyan eruption which has four stages Glen. It is named after the Island of Surtsey which was created in this way. Once the cone of the volcano reaches 100 metres below sea level the water pressure no longer has the power to stop an eruption coming to the surface so as this cone grows closer to the surface we are likely to see the large plumes of smoke and dark rooster tails and ash which may create an Island if it is followed by lava flow to seal it from erosion from the sea.

[jand]

Fifi

Is there still the danger that this new island/cone is now under El Hierro itself and the whole island could go if it erupts directly under it ?

[pennylane]

ok I've read it but I'll just put this link up to save re posting all
the photos of the rocks etc....

http://www.volcano.si.edu/world/volcano.cfm?vnum=1802-05=&volpage=var

[fifi]

The Island is supposed to have about 1000 volcano cones so I guess the lava could come out of any of the ones that are connected jand or even in fissures. It seems to like the spot in La Restinga though which is the safest place for it to happen. One explanation which I could understand was using the idea of squeezing a  tube of toothpaste as an example, when the earthquakes happen in El Golfo area, the force of them squeezes the lava out the other end and it ends up in La Restinga.

[pennylane]

Thanks for that explanation Fi......
so what stage is it at now ?
and during the same activity in the Azores, how does this at El Hierro compare ?
The dates of that are 1998 to 2000.
So would the four stages take two years ?

I'm still reading up on it x

[fifi]

The eruptions can stop and start. Surtsey Island took about four years I think to be made. Basically it depends on the duration of the eruption and  how big the pile of debris is. Picture a big pile of rock and ash being emmitted which grows so big that it is above sea level and  needs to be sealed by lava to stick it together. Without the lava flow it will just erode away.

I think this eruption is at stage 2 because we havent seen the huge clouds of smoke and rooster tails full of ash yet.

This is the next stage which may or may not happen. http://www.youtube.com/watch?v=JwEprwMGPq4&feature=related

[fifi]

There have been two very shallow earthquakes in the North, one less than a Km and the other 1.9km.http://www.avcan.org/?m=Animacion

[kevin2003]

quote:Originally posted by fifi

The eruptions can stop and start. Surtsey Island took about four years I think to be made.

[fifi]

http://www.youtube.com/watch?v=UeX0jXQnxTY&feature=related []

[jand]

Data Update 27/11 – 16:20 – Ian Carson reports from La Restinga
- Scientists back confirmed been into Jacuzzi but lots of gas, sulfur and chlorine.
 - Vent confirmed at 1.8 km from coast.
 - Length of ship,' Salvamar Adhara' for comparison purposes is 21 meters.
 - Steaming stones area bigger + brown stain.
 - Rocks are hot when arriving at the surface, they have to use gloves to handle

[TripleH]

quote:Originally posted by kevin2003

quote:Originally posted by fifi

The eruptions can stop and start. Surtsey Island took about four years I think to be made.

Kevin, can you ready a pic for jands millionth post? It could happen before the volcano

[kevin2003]

quote:Originally posted by TripleH

Kevin, can you ready a pic for jands millionth post? It could happen before the volcano

[Paddster]

[jand]

Data Update 27/11 – 16:20 – Ian Carson reports from La Restinga
- Scientists back confirmed been into Jacuzzi but lots of gas, sulfur and chlorine.
 - Vent confirmed at 1.8 km from coast.
 - Length of ship,' Salvamar Adhara' for comparison purposes is 21 meters.
 - Steaming stones area bigger + brown stain.
 - Rocks are hot when arriving at the surface, they have to use gloves to handle

[TripleH]

G'night everyone. Sleep tight

[pennylane]

Serreta Volcanic Ridge

The submarine eruption that started on December 1998 from multiple vents along the Serreta Volcanic Ridge,
about 10 km west of Terceira Island, Azores, continued through March 2000.
Vents along the ridge were very active between December 1998 and September 1999.
Activity then declined to very low levels with rare surface manifestations through December 1999.
Activity increased again in late January 2000.

Several times during 1999 basaltic lava balloons were observed floating in the eruptive area.
These "balloons" are very hot, gas-rich, lava fragments produced from small submarine lava lakes/fountains.
During ascent to the surface, magmatic gas exsolves from the hot fragments,
increasing the volume of the balloon while the crust is glassy and expansible.
Once at the surface, interaction between the hot blocks and seawater produce white steam columns
that can be seen from land when meteorological conditions are favorable.
The blocks eventually sink after the gas escapes