This is a just minor test that I was doing. Here is the audio file of the magnitude 5.6 earthquake as I did record it on Hvammstangi geophone station on 21. October 2012. This audio is about 4 seconds long.
Test audio file. Click to listen or download.
During the night. Harmonic tremor levels started to drop in Grímsfjall volcano. The reason for this harmonic tremor level increase remain unknown and unclear. But no volcano related activity has been seen or recorded so far in Grímsfjall volcano.
Harmonic tremor levels in Grímsfjall volcano. This is high resolution image. Copyright of this image belongs to Icelandic Meteorological Office.
Harmonic tremor levels in Grímsfjall volcano. This is low resolution image. Copyright of this image belongs to Icelandic Meteorological Office.
Some earthquake activity has been taking place following this events. But the earthquakes have been small and do not suggest anything is about to take place in Grímsfjall volcano.
Earthquake activity in Grímsfjall volcano for the past 48 hours. Copyright of this image belongs to Icelandic Meteorological Office.
So far Grímsfjall volcano has remained quiet during this glacier flood. With nothing suggesting that it is going to change soon. As for the glacier flood it self. According to latest news it seems to have peaked and is now dropping. But this was a small glacier flood. With just rise about 153 cm. But that is quite small compared to many older glacier floods from Grímsfjall volcano.
Icelandic News about this glacier flood
Hlaupið í Grímsvötnum virðist hafa náð hámarki (Vísir.is)
Hlaupið í Gígjukvísl í rénun (Rúv.is)
Blog post updated at 12:48 UTC on 27.11.2012
It is unclear what is going on in Grímsfjall volcano at this moment. Harmonic tremor level continue to rise. They are currently way above what is normal for minor glacier floods from Grímsfjall volcano. This might be a minor eruption, or it might just be glacier on the move inside caldera. Whatever it is. This is not a strong event. As it only appears so far on only one SIL station. The one located on top of Grímsfjall volcano. Other SIL stations do not show any change so far. There is no earthquake activity in Grímsfjall volcano so far following this activity.
Grímsfjall volcano tremor levels this morning at 09:20 UTC. This is high resolution image. Copyright of this image belongs to Icelandic Meteorological Office.
Tremor levels at Grímsfjall SIL station (low resolution). The spike is maybe an earthquake. Copyright of this image belongs to Icelandic Meteorological Office.
So far nothing there is no word from Icelandic Meteorological Office on what is going on in Grímsfjall volcano. I am also uncertain what is going on in Grímsfjall volcano at present time. But I am sure that is going to get clearer in the next few hours. The harmonic tremor level appears to be continue to rise. So it might get confirmed in the next few hours if there is an eruption in Grímsfjall volcano or not.
I have changed my mind on taking the geophone network down. The main reason being that data is valuable. The data that I am collecting today has value. I did not release this until this morning. After I had been telling the person who hosts my Hvammstangi geophone that data has value yesterday. This is also true for my geophone network. But it is going to cost me a lot to keep it running as is. The largest cost being maintenance and internet cost over 3G (2190 ISK, 13,41€ a month pr. 3G connection where that is used).
But this is it. My geophone network is going to stay up until I can replace it with a better network in the future. When that is going to happen I do not know. But I hope it is going to take me less then 10 years until I can start to implement that plan.
Current glacier flood from Grímsfjall volcano continues to grow in size. To everyone surprise I think. Currently the glacier flood remains small. Harmonic tremor on Grímsfjall SIL station continues to grow. But this is due to the glacier flood. Not any volcano activity so far.
Harmonic tremor during this glacier flood from Grímsfjall volcano. Copyright of this image belongs to Icelandic Meteorological Office.
Conductivity of the glacier water remains high. But this means glacier food water is in the river. As oppose to any normal melt water coming from the glacier it self. This current glacier flood is the second glacier flood from Grímsfjall volcano this year. But earlier this year a small glacier flood did go from Grímsfjall volcano. My coverage of that glacier flood can be found here (28.01.2012) and here (29.01.2012). Current glacier flood started on Wednesday. So it has already been ongoing almost four days at current time. I am going to post more updates on this glacier flood if needed.
Icelandic news about this glacier flood
Enn vöxtur í Gígjukvísl (Rúv.is)
Vatnshæð í Gígju enn að aukast (mbl.is)
Vatnshæðin um tveir metrar (Vísir.is)
A minor glacier flood has started from Grímsfjall volcano glacier lake. This glacier flood is expected to be extremely small. Since last glacier flood from Grímsfjall volcano took place earlier this year. That glacier flood was also small. Minor harmonic tremor changes have been taking place on Grímsfjall SIL stations. But they are not strong and can easily drown in wind noise. But it has been a stormy few weeks in Iceland.
Harmonic tremor changes on Grímsfjall SIL station. Copyright of this image belongs to Icelandic Meteorological Office.
I do not expect any volcano activity to take place following this glacier flood. As last eruption in Grímsfjall volcano took place last year and that eruption was the largest one in 140 years at least. But I am going to keep monitoring this activity and post updates if anything changes.
Icelandic News about this glacier flood
Lítið hlaup hafið í Grímsvötnum (Rúv.is)
Vatnamælingamenn á leið austur (Rúv.is)
Hlaup að hefjast í Grímsvötnum (Vísir.is)
Lítið hlaup hafið í Grímsvötnum (mbl.is)
It has been quiet in Iceland for the past few weeks. Mostly due to bad weather. But that drops the SIL network ability to detect minor earthquake activity in Iceland.
Hofsjökull volcano is among Iceland most quiet volcanoes. With no eruption documented in historical times. Hofsjökull volcano is also a interesting volcano. As it more like two volcanoes in one. Why that is I am not sure. Hofsjökull volcano is covered with a glacier that is up to 650 meters thick in the central caldera.
The earthquake in Hofsjökull volcano. Copyright of this image belongs to Icelandic Meteorological Office.
This earthquake was small. Just magnitude 1.3. But with the depth of 22,4 km. So it took place in the magma chamber, or close to it. Rather then any crustal earthquake activity. But it is hard to know for sure at the moment. During a normal year. Hofsjökull volcano can have up to 10 earthquakes during the year. Some years there are no earthquakes at all in Hofsjökull volcano.
Tjörnes Fracture Zone
Earthquake swarm that started on 20th of October in TFZ continues to this day. But currently the earthquake activity is just minor earthquakes at the moment. But the swarm is ongoing now for one month. There are also no signs of this earthquake swarm stopping. Even if the earthquakes are just minor ones for now.
Current earthquake activity in TFZ today and past few days. Copyright of this image belongs to Icelandic Meteorological Office.
I fully expect the earthquake activity to continue in TFZ. When it might stop is impossible to know for now. So keeping an eye of this area of TFZ is a good idea. The risk of large earthquake taking place in this area remains unchanged last I knew.
Here is a short update on earthquake activity in Iceland. It has been stormy few weeks so recorded earthquake activity has not been a lot in Iceland.
Tjörnes Fracture Zone
Earthquake activity continues in TFZ. A bit less then when it did start on 20. October 2012. But it still moves along. The risk of large earthquake area remains for this area. When, where and how big remains unknown factors so far.
Earthquake activity in TFZ. Copyright of this image belongs to Icelandic Meteorological Office.
Herðubreiðarfjöll volcano is a small volcano (no GVP entry that I know of) just north of Askja volcano. But Herðubreiðarfjöll volcano are in fact part of Askja volcano fissure swarm. But I do not think they are part of Askja volcano as such.
Earthquake activity in Herðarbreiðarfjöll volcano (the blue dots). Copyright of this image belongs to Icelandic Meteorological Office.
The earthquake activity in Herðurbreiðarfjöll volcano was most likely a minor dike intrusion into the volcano. What that means is too early to say at this moment. But most likely it does not mean anything for now at least.
There has been some minor ice-quake activity in Iceland when the temperature drops below 0 degrees in Iceland.
It is not easy for me to make this decision. But I have dedicated to end my geophone network as it is today in December 2012. The reason is cost of running it. I just can’t afford it. I am also dealing with cost of hardware, maintaining that hardware and so on. That is just how it is. Dealing with technical problems is also a factor in this. Computers die, hardware needs to be replaced after certain amounts of years. This all costs me money. Technical assistance by the people who are hosting the geophone hardware also costs time for them. It also costs money for them in electricity cost (not a lot. But something as all the hardware uses electricity).
While it is great being able to track earthquake activity in real time (5 min delay on my web page). I just cannot afford it. I am also not going to move back to Iceland. So that makes maintaining my geophone network today even harder. So in December 2012 this is going to be all over. All my geophone network stations are going to go offline and that is going to be end of that. I am going to keep the hardware for later use somewhere else. Where and when that might be is unknown at the moment.
I want to thank everyone how did support my effort in building my network as it is today (buying Skeiðflöt and Eyrarbakki geophone stations). Sadly I can no longer maintain the geophone network as explained above. But that is just how it has to be.
Following geophone stations go offline in December 2012
Following geophone stations are going to remain online
Bov, Denmark (but the web page is going to move soon to a new server)
While the current geophone network is coming to an end. It does not mean that I am going to quit my plans so easy. I plan on building a new network of seismometers (proper ones) in Iceland when I can afford it. When that might happen I do not know. But I am going to build it in a SIL style. The seismometers are also going to be located far from any human traffic so I won’t have any noise from that or any other cultural noise source (at least, keep it at minimal). I am also going to hire people and create a company around this to take care of the hardware and process the earthquake data gathered.
I am going to build seismometers network in the following place when I can afford it (this means. When I am rich).
Canary Islands (maybe. Not sure yet.)
Falkland Islands (Details pending)
The new network is going to be a proper network. It is also going to be in places that Iceland Meteorological Office has no SIL stations at the moment. But this is going to take a while until it happens. So all that people can do is to wait until I am ready to do this. It is going to take a few years at least.
Earthquake activity has renewed at TFZ. The area that is activate is the same area that had earthquake swarm from about 1 month ago. But largest earthquake in that swarm was a Mb5.6 earthquake. The largest earthquake today was a magnitude ML3.3 earthquake at 12:12 UTC. A magnitude 2.8 earthquake did take place at 13:08 UTC.
Current earthquake activity in TFZ. Green star mark the magnitude magnitude ML3.3 earthquake. Copyright of this image belongs to Iceland Meteorological Office.
The risk of large earthquake in this area still high. When it might happen is impossible to know for sure. There have been reports of the largest earthquake being felt in the town of Siglufjörður and other nearby areas. I fully expect earthquake activity to continue in this area. There have been stormy conditions in Iceland for the past 24 hours. This winter storm is making it more difficult to detect smaller earthquakes in this area, as in other areas of Iceland.
This earthquake activity appears clearly on my geophone in Hvammstangi. Even if there is a lot of wind noise taking place.