Day: July 8, 2011

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Harmonic tremor in Katla volcano

At the moment there is an ongoing harmonic tremor going on in Katla volcano. It is just an small one, just above the background level noise floor. This is most likely an small dike intrusion. But nothing in the data from Icelandic Met Office suggests that an eruption has started in Katla volcano at this stage. But that might change without an warning, since this is an volcano after all. This change in harmonic tremor does not seems to be created by an glacier flood of some type. What is interesting is that this harmonic tremor pulse looks like an harmonic tremor pulse detected in the year 1999, just before an small eruption took place in Katla volcano southern caldera rim.

This harmonic tremor is in the high frequency range at the moment. But no change has been seen in the low frequency range at the moment. This is the same thing that did happen in the year 1999. At the moment however it is too early to know what is going to happen in Katla volcano for sure. All that can be done is to watch and wait. This might quiet down, or it might not. Only time is going to tell us what happens next. At the moment the harmonic is falling at fast rate, so this might be over.

Before the harmonic tremor pulse there was an earthquake swarm in Katla volcano caldera. The largest earthquake was ML2.1 and that was an long period event, but that tells me that magma was the source of this earthquakes in Katla volcano caldera. There where two earthquake swarms in the caldera today, but that makes total of three earthquake swarms in the Katla volcano caldera since the beginning of June.


The two earthquake swarms that took place in Katla volcano caldera today. Copyright of this picture belongs to Icelandic Met Office.


The only earthquake that I did record out of this earthquake swarm. This earthquake was ML2.40 with the depth of ~400 meters. This plot is filtered at 1Hz . This picture is released under Creative Common licence. See Licence web page for more detail.


Spectrogram of the ML2.4 earthquake in Katla volcano from this morning. This is filtered from 1Hz. This picture is released under Creative Common licence. See Licence web page for more detail.


Harmonic tremor can clearly be seen at the end of this tremor chart from the Icelandic Met Office. Copyright of this picture belongs to Icelandic Met Office.


Harmonic tremor can be seen at the end of this tremor chart from the Icelandic Met Office, but it is not clear at this SIL station. Copyright of this picture belongs to Icelandic Met Office.


Harmonic tremor can clearly be seen at the end of this tremor chart from the Icelandic Met Office. Copyright of this picture belongs to Icelandic Met Office.


Harmonic tremor can clearly be seen at the end of this tremor chart from the Icelandic Met Office. Copyright of this picture belongs to Icelandic Met Office.


Harmonic tremor can be seen (not clearly) at the end of this tremor chart from the Icelandic Met Office. Copyright of this picture belongs to Icelandic Met Office.


Harmonic tremor can clearly be seen at the end of this tremor chart from the Icelandic Met Office. Copyright of this picture belongs to Icelandic Met Office.

The harmonic tremor is strong enough on many SIL station to go above the background noise level on the SIL stations (wind, ocean waves etc..). But this is not an strong harmonic tremor. They can be stronger.

This does NOT mean an eruption is imminent in Katla volcano. What this does mean that is an magma is on the move inside the Katla volcano. What happens at later time is something that nobody can guess at current time. But it is now time to watch Katla volcano even closer.

It is also important to notice that nobody really knows how Katla volcano behaves before an eruption. We only get those answers after an eruption in Katla volcano. For the moment we can only wait and see what happens in Katla volcano.

I am going to post more updates if anything interesting happens. Also, there seems to have been an Long period earthquake at 22:14 UTC, most likely in Katla volcano. It appeared on my geophone close to Hekla volcano. I am guessing the size of this earthquake is ML2.0+.

Blog post updated at 22:39 UTC. Spectrogram picture added.

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Last update on Hekla volcano (for now). Correction on mobile emergency SMS. Earthquake swarm at Reykjanes Ridge. The media hype. Help needed!

Here is an short update on few things.

Hekla volcano: Everything is quiet at Hekla volcano. Movements of magma deep down in the crust have not changed that fact. Nobody knows when it is going to stop begin quiet. Until it does. There is no need to worry about it. Update 2: The movement on the GPS instruments was most likely an deep dike intrusion in Hekla volcano. It was not followed by any earthquakes for some reason.

Correction: I did say that in my earlier post that if there was an emergency in regards to Hekla volcano due to an eruption. The Public Emergency Authority in Iceland would send out an SMS to everyone in the local area. This is half wrong and half correct. They are going to send an SMS, but apparently only to registered locals in the area. Few years ago there was talk of setting up an system to send SMS to everyone around Hekla volcano if an eruption would start. But that system appears not to have gone past the idea stage. I do not watch the changes in this field, so I did miss that. For that I am sorry.

Earthquake swarm at Reykjanes Ridge: Few days ago there was an minor earthquake swarm at Geirfulgasker on the Reykjanes Ridge. This was normal tectonic activity for this area. But it has been having earthquake swarm every few months now for an long time. This earthquake swarm was an small one compared to many other earthquake swarms that have been taking place there.

The media hype: To Daily Mail in the UK. I am not an volcano expert. I also don’t claim to be one. You can’t find that claim on this blog. Because I am not an volcano expert. You also got an wrong volcano in your news and you spelled the name wrong on Hekla volcano. You should correct your news if you want to call your self an newspaper. Also, nobody sad anything about possible size of an ash cloud from Hekla volcano. You just made that up. The media should also relax, drink less coffee. There is nothing going on at the moment. You can hype all you want when something interesting is going on. If the media doesn’t get what I am saying, this here (Youtube, Newswipe) should help you get the clue. I at least remain hopeful, or something.

Help needed!: I need help. I am broke again (demit!). I might be having an low paying job. But my pay goes mostly up to my debts and July was an bit harder then I expected (I try to leave something for food, but this time around it did not work out as I planned it). But that was due to the last VISA payment that I am ever going to make. I am going to get paid on the 1 of next month at least. I am now only left with 2500 ISK (€15) and €24 (182 DKK) to buy food (total 39€) for the rest of the month or until I get paid from my job. My social welfare (that I working toward getting off one day) is always paid on the 1st of every month. My rule about asking for donations is that it is the only option that I have left. Besides not eating anything. But I don’t really regard that as an good option. My status is that the worst is most likely over now, since no more surprise VISA bills (I closed it and I am glad!) and now it is just steady payments of the overdraft until it is finished. But that going to take about 6 to 11 months to finish. Depending on the work income that I have until the end of October this year. If anyone wants proof of how broke I am, I can provide it.

So I once more ask again for donations so I can eat something this month. I am living cheap, but at the moment it did not work out as I planned. Thanks for the help in advance! 🙂

Other: I cancelled going to school this autumn. I am going to work more to pay down my debts faster. Then I plan moving to Denmark in the year 2012, when I have the money to move again. But from end of October I am going to provide regular and good updates in regards to volcanoes and earthquakes, since I won’t be working from that time in companies. But I am going to be working on a book that I am going to publish early 2012 (I hope).

Update 1: For everyone how donates there is going to be an e-book (pdf format only from me) about Icelandic volcano eruption for anyone how wants a copy. But I plan on writing book about volcano eruptions in Iceland soon after they happened. I finally made up my mind on how to write that type of book. It won’t take me an long time write those books, since it is just facts and details about the eruption. I am also going to sell those books on Amazon Kindle and web page named Smashwords. I hope to release the book about Eyjafjallajökull volcano eruption 2010 in December 2010 or January 2011.

Blog post updated at 00:27 UTC on 8. July 2011.
Blog post updated at 07:19 UTC on 8. July 2011.