Today (28.05.2012) at 11:22 UTC an small earthquake swarm did start in Katla volcano. This earthquake swarm did end at 12:28 UTC. This is small earthquake swarm, both in numbers of earthquakes and in the magnitude of the earthquakes in the swarm. With the largest earthquake having the magnitude of ML1.4. The depth of this earthquake swarm was around 0.1 km, but that gives the depth around 100 meters or so. Following this earthquake there has been some minor disturbance at Álftagróf SIL station. But because it only appears on one SIL station. This change might have its origin in something else. Like human traffic, local wind etc. For the moment I cannot rule that out.
The change in tremor at Álftagróf SIL station. This change in tremor might not be because of Katla volcano. But something else. Please keep that in mind. Copyright of this picture belongs to Iceland Meteorological Office.
If the tremor changes at Álftagróf SIL station where from Katla volcano. They where highly local and did not show up on other SIL stations for some unknown reason. That has happened before, but the SIL network was not as dense around Katla volcano back then.
I find it most likely reason for this earthquake swarm where some changes in hydrothermal areas inside Katla volcano caldera. All hydrotheraml areas in Katla volcano are under high pressure due to the glacier that is on top of them. So changes might not happen without some earthquake activity as did happen few hours ago. This is also not in any way a sign that Katla volcano might be about to erupt. This is far too low earthquake activity for such event to be starting. There is an chance of small glacier flood following this earthquake swarm in next 8 to 24 hours. But it is far from certain that is going to happen.
It has been rather quiet in Iceland during past few weeks. This seems to be continuing to some extent. There are few earthquakes and nothing noticeable is taking place in Icelandic volcanoes at the moment. While this quiet time is currently I am going to enjoy the summer a little bit. I am also trying to survive the heatwave that has been taking place in Denmark + Northern Europe for the past 10 days. As currently I am not used to type of heat (over 25C). But that is going to take some time until I do.
I am going to try and write something while it is quiet in Iceland. But this quiet time is going to mean longer time between blog posts. But I am sure that something of interest is going to happen soon in Iceland.
I have been having this issue for some time. I have already tried to fix it already. But that solution has not worked, and if I want to move to 3G connection it is going to cost me at least 15900 ISK, 97€, $123, 726 DKK. The problem is rather continued connection dropout. The connection that I am currently using is a 2Mbps ADSL connection that owners of the farm have, but over an poor phone line that does not carry ADSL signal so well (as I suspect is the case rather then anything else that I have think of before). There is an good 3G 900 signal in this area. So my solution would be to move this to 3G internet, rather then anything else. The connection charge pr month would be 1690 ISK (10€, $13, 77DKK) for 3GB of data. With that move. I should solve the connection dropout issues permanently.
This appears on my geophone web page with lack up updates for the Skeiðflöt geophone station. If it was connected normally, as it is going to be soon. This would result in green lines all over the helicorder image. Something that is not good, and makes it harder for me to monitor Katla volcano in real time. I plan on fixing this next month by switching over to 3G connection at that location. So I guess that June is going to be a bit broke for me as well (thankfully, there is cheap food in Denmark that I can buy. But I am still going to be broke). But I am going to work out the money issue somehow in the end.
It seems that Krísuvík volcano is inflating and deflating on regular basic. I do not know how regular this change is. But it has been noticed by Icelandic scientists how are bit puzzled by this behavior. Last inflation episode did last until end of the year 2011. Since then deflation did start again and is currently ongoing. It is uncertain if what this means. At the moment it is too early to know for sure if this means if that Krísuvík volcano is getting ready for an eruption. But if there was an eruption in Krísuvík volcano, it would be Hawaiian eruption so no volcano ash. Volcano ash eruption would only take place if an eruption started in Kleifarvatn lake. But the effects of that would be limited to local area (Reykjavík and other nearby towns). It would not create any global problems, as many would want to believe.
Inflation and deflation period have been the years 2009, from January to September. In May 2010 inflation did start again, that inflation period lasted until end of the year 2011. Since then deflation has been taking place. Today there is continues GPS monitoring in Krísuvík volcano. But it is unknown if this type of behavior has taken place before in Krísuvík volcano. But for now Krísuvík volcano is being monitored both with GPS and the SIL network. What happens next anyone guess.
Icelandic news about this.
Land rís og sígur í Krýsuvík (Rúv.is)
The earthquake activity in Herðubreið during past few days is not volcanic in nature, or magnetic in nature. It is purely tectonic in nature. But the faults that have been moving are vertical, not horizontal as so many earthquake faults. Earthquakes are common in this area, as it on the eastern rift zone. The fault lines in this area of Iceland are highly active at times. Iceland Metorlogical Office has released this interesting information about the earthquake activity in this area during the past few years.
Most of the earthquakes are on the depth of 5 to 6 km according to IMO.
Total amount of earthquakes in Herðubreið from the years 2005 to 2012. This clearly shows that activity in this area has been rather constant during this period. Copyright of this image belongs to Iceland Meteorological Office.
The area in question is outside Askja volcano main fissure swarm. It is also outside Kverkjföll volcano main fissure swarm. So this earthquakes are tectonic in nature. But even so this area has erupted in the past. But for now. It is just earthquakes and not magma on the move, or breaking its path up to the surface as was case in Upptyppingar tuff mountain. The images are from Week 20 overview (what is up about it) at IMO web site.
At 04:03 CEST (02:03 UTC) an earthquake with the magnitude of Mw6.1 did happen in north Italy. This earthquake was in an area that has seen a lot of earthquake activity during past several months now. But earthquake activity did start in this area late last year (2011). This earthquake did create a lot of damage in north Italy according to news reports. At least seven people have died from this earthquakes and well over 50 people have been injured because of this earthquake. Many historical sites have been damaged or completely ruined in this earthquake. I do not know what type of fault that did break. But data suggest that it was a slip fault that did break. I am unsure on directions of the fault that did break.
The earthquake in Italy as I did record it in Aabenraa, Denmark. There was a lot of surface waves following this earthquake. But those waves can be seen after the S-wave of the earthquake. This image is released under Creative Commons Licence. See CC Licence page for more details. Owner of this image is Jón Frímann Jónsson. Software used is WinQuake.
The magnitude Mb5.2 earthquake in Northern Italy. I did not record this earthquake as clearly as the strongest one. This image is released under Creative Commons Licence. See CC Licence page for more details. Owner of this image is Jón Frímann Jónsson. Software used is WinQuake.
What is most interesting about this earthquake is that it was had a pre-earthquake with the magnitude of ML4.2 about an hour to two hours before the main earthquake did happen. Web page of EMSC is not working properly at the moment. So I can’t check the time of the pre-earthquake at the moment. There have been more then dozen aftershocks less then Mb4.0 in size. But there have also been several earthquakes with the magnitude of Mb4.5. This aftershock activity continues at the moment.
Update 1: According to EMSC the pre-earthquake took place at 23:13 UTC on 19.05.2012.
I am going to update this blog post as more information are published.
English news about this earthquake.
At least 7 dead after quake rocks northern Italy (CNN.com)
Deadly northern Italy earthquake hits heritage sites (BBC News)
In pictures: Italy earthquake (BBC News)
Blog post updated at 15:44 UTC (17:44 CEST) on 20.05.2012.
The earthquake swarm that started in Herðubreið two days ago continues. So far over 100 earthquakes have been recorded. Most of them are less then ML2.0 in magnitude. But this earthquake swarm continues at slow rate. This is not a big earthquake swarm. Based on number (in my system) of earthquakes pr hour. But in my system, a large earthquake swarm has tens to hundreds of earthquakes pr hour.
There is some earthquake activity in Katla volcano. But it is not high. There was one small earthquake this evening (it did appear on my Skeiðflöt geophone). But it has not been reviewed. So both size and depth are going to change.
The earthquake activity in Katla volcano is also showing interesting pattern during this week (Week 20). It seems that earthquake activity is focusing on one point inside the caldera. It is hard to know for sure what this means at current time. But it is my opinion that it is not a good sign. But so far, nothing major has been happening inside Katla volcano caldera at this time. Until that happens, it is just best to keep watch and keep speculations within the amount of what is going on.
Beside this activity. It has been quiet in Iceland now for several weeks now. That is not un-common to happen during some years. While other years are often more active, some years are quiet. It is not clear yet if the year 2012 is going to be quiet year in Iceland or not.
This morning there was a short earthquake swarm in Katla volcano caldera. This earthquake looks like a minor dike intrusion did take place this morning. Current series of events did start on 28. April 2012. With a small earthquake event and a small glacier flood that did follow it. Along with harmonic tremors coming from the glacier flood and possibly Katla volcano caldera (hydro-thermal activity boiling or something of that nature). I do not yet know if there was any glacier flood following the event this morning. But so far there is nothing that suggests a small glacier flood did take place following the earthquake swarm this morning.
The earthquake swarm this morning took place on an location that did erupt on 8 and 9th of July 2011. So it is clear the area that erupted last year is picking up activity again. But there was an drop in activity from end of November 2011 until end of April 2012.
This earthquake activity did appear well on my geophone at Skeiðflöt farm.
Earthquake activity in Katla volcano caldera this morning on my Skeiðflöt geophone. There is a lot of noise on this geophone. But earthquake activity can still be seen on this. The earthquakes are marked by red (some noise is also marked by red). This picture is released under Creative Commons Licence. See CC Licence page for more details.
It is clear that Katla volcano seems to be warming up to an eruption. But it is impossible to know when such eruption might happen, or how big it is going to be.
Earthquake activity continues south-west of Herðubreið. But almost all of the earthquakes have been less then ML2.0 in magnitude. Earthquake activity has been slowing down all day. At the moment, it appears this earthquake swarm is close to being over.
This area is well known for for earthquake activity. So this is not something that is new in this area.
According to EMSC and USGS there have been several earthquakes with the magnitude of Mb4.5 to Mb4.8 on the Reykjanes Ridge. Earthquake activity is common on the Reykjanes Ridge. But because of the location and depth (around 2km) it is impossible to know if there any volcano eruption taking place at this location. It might well be, or not.
Over the past weeks there has been some earthquake activity close to or in Kolbeinsey Island. The largest earthquakes have had the magnitude around ML3.0, with some underestimates due to distance from the SIL network. At this moment it is impossible to know if this earthquake activity is related to possible eruption activity. But it believed that an eruption (or dike intrusion) took place on Kolbeinsey Ridge in the year 1999. It started off with a large earthquake swarm.
Today a small earthquake swarm started just south-west of Herðubreið. But Herðubreið is a volcano cone formation that erupted during last ice-age. But that eruption did break up trough the glacier. Explaining its shape.
Largest earthquake so far had the size around ML3.1. But aftershocks have reached the size of ML2.5 according to IMO automatic magnitude estimate. This earthquake swarm is currently ongoing.
Icelandic news about this.
Plus. Here are pictures from The Telegraph of Iceland volcanic nature.
Other: Donations help me running this blog (they also help me paying the bills, buy food and what comes with being a human being). Plus it appears that I need go the dentist. But as it is now. I can’t afford it properly. Thankfully this is not an emergency that I am dealing with in one of my tooth. But I need to get it fixed one way or the other soon. Thanks for the support! 🙂