Day: October 14, 2011

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Special report: Update 3 on El Hierro eruption in Canary Islands, Spain

I am going to fully integrate Canary Islands into my watch volcano monitoring system in the beginning of next month, but Canary Island won’t be part of my emergency system until I move to Canary Island (that is because of technical reasons mostly). When that happens, blog post regarding earthquake and volcano activity won’t be a special report. Just a normal blog post as with Icelandic volcanoes. I am doing this as I plan on moving to Canary Islands in about 10 years time (+- maybe few years depending on how my plans work out). A name change on this blog is planned in the beginning of the year 2012. But it takes a while for me to think up a new name for this blog.
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The eruption in El Hierro volcano continues at the same phase as before. With little change so far. Currently the eruption seems to be in two vents, as it did when it started on Monday. There have been unconfirmed reports of new vents opening up closer to the coastline. But given lack of direct evidence that should be there. I do not believe that a new vents have opened up closer to the coastline so far.

Deep earthquake continue in El Hierro volcano. But that means a new magma is coming in from the mantle and is flowing upwards into the volcano. For long as deep earthquakes are being recorded the eruption is going to continue. It is impossible to know for how long this inflow of magma from the mantle is going to continue. But this means that the eruption is going to continue for time being. With the risk that new vents might open up at any time on and around El Hierro volcano. This inflow of new magma has also been confirmed by GPS measurements on El Hierro volcano (the island). But since the eruption did start, no major change has been seen on the GPS real time data.


The harmonic tremor in El Hierro volcano yesterday. Copyright of this picture belongs to Instituto Geográfico Nacional.


The harmonic tremor in El Hierro volcano today (until 21:20 UTC about). As can be seen by comparing the pictures between today and yesterday. Not much has changed since yesterday in terms or harmonic tremor. Copyright of this picture belongs to Instituto Geográfico Nacional.

If a eruption vents open up on a land. The following eruption is going to be lava only. No volcano ash and no explosions as El Hierro is a shield volcano like the one on Hawaii and that means only lava eruptions. If a eruption vents opens up on the shallow coastline, there are going to be explosions for as long the ocean water can get into the crater. The moment it closes up the explosions stop and lava eruptions starts.

Please note that I am on slow internet connection (3G). So I am not going to post anything if the internet connection is really slow, as sometimes seems to happen. I am going to try and solve this issue by using my 3G phone and connect that way. At least I am going to try and see what happens.

Blog post updated at 03:20 UTC on the 15 October, 2011.

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Earthquake swarm in Askja volcano and Katla volcano

During the night there was a earthquake swarm in Askja volcano and in Katla volcano. The earthquake swarm in Katla volcano might be ongoing, but it is hard to know that for sure at the moment.

The earthquake swarm in Askja volcano are signs that volcano is preparing for a eruption period. But it seems like that magma has been starting to collecting in Askja volcano last year (in March of 2010). This progress also seems to be moving along faster then I did expect last year. But the earthquake swarm that took place during night was because if a possible dike intrusion from Askja volcano that got into the crust inside Askja volcano fissure swarm. So far the pressure of the magma is not high enough to start a eruption and I am unsure how long this progress needs to continue before Askja volcano is ready for a eruption. The largest earthquake that happened during the night was ML3.4 and on around 1 km depth according to the news on Rúv.


The earthquake area in Askja volcano. It is outside the main Askja volcano, but inside Askja volcano fissure swarm, the star marks the location of the ML3.2 earthquake (automatic size). Copyright of this picture belongs to Iceland Met Office.

Earthquake activity continues in Katla volcano as before. Most of the earthquakes are as before just small ones. Currently the earthquakes do not appear to be from dike intrusion as happened last week (5 October, 2011) with the earthquakes that where up to ML3.9 in size (checked data). After this large earthquake swarm activity dropped considerably. But it has been picking up again slowly during the week. But earthquake observation has been difficult due to frequent storms during the past two weeks that have been passing over Iceland. This storms have had wind up to 30m/s and wind gusts up to 56m/s (recorded).


The earthquake swarm in Katla volcano caldera. This area was active this summer when there was a minor eruption in Katla volcano. Copyright of this picture belongs to Iceland Met Office.

For the moment it is hard to know what happens next in Katla volcano or in Askja volcano. But it is clear that Askja volcano is preparing for a eruption (along with Kverkfjöll volcano). It is clear that Katla volcano is continuing to prepare for a eruption. But it is impossible to know when and how big that eruption might be. Until a eruption takes place, more dike intrusions with following earthquake swarms should be expected in Katla volcano.

Note: I am going to write more on El Hierro volcano (Canary Islands, Spain) later today. When I know more on what is going on in that volcano. But information gathering takes a little time when it is in a language that I do not properly understand yet.

News on this from Rúv.is.

Jarðskjálfti við Lokatind (Rúv.is, Icelandic)

Blog post updated at 14:23 UTC on 11 October, 2011