Month: September 2012

Posted on

Ongoing earthquake swarm in Breinnisteinsfjöll volcano / SISZ

Since yesterday (02.09.2012) there has been ongoing earthquake swarm in Breinnisteinsfjöll volcano / SISZ (south iceland seismic zone). It is impossible to know how this earthquake swarm is going to proceed. But from what I can tell. It does not seem like it is going to be over any time soon. It is also an possibility that current earthquake swarm is part of an larger stress change in the area. But for now it is too early to know for sure what it means in the long term. Current earthquake activity is ongoing. With almost no breaks or stops. Most earthquakes have the magnitude of 0.1 and up to 2.0. But no larger earthquakes have been detected so far. The first earthquake in this earthquake swarm had the magnitude of ML4.4. Depth of this earthquakes is from 3 to 7 km (in that range).


The earthquake activity in Breinnisteinsfjöll volcano. The earthquakes align them self on an fault line that almost directly north-south direction. Copyright of this image belongs to Icelandic Meteorological Office.

It is impossible to know what is going to happen next in this earthquake swarm. But strong earthquake should not be ruled out for now. This might also activate nearby fault lines if the activity intensifies. As that sometimes happens in Iceland. Whatever happens next in this area. It is worth keeping an eye on the progress of this earthquake swarm.

Icelandic news about this earthquake swarm

Enn skelfur undir Bláfjöllum (mbl.is)
Enn skelfur í Bláfjöllum (Rúv.is)

Posted on

Harmonic tremor pulse activity maybe in Hamarinn volcano

Today (02.09.2012) a harmonic tremor pulse did start in Hamarinn volcano (best guess) (Bárðarbunga volcano). This harmonic tremor pulses are intermittent and normally last for up to 20 to 30 min., at the time. What is creating them is hard to say. But this might just be hydro-thermal activity taking place in Hamarinn volcano. This might also be magma on the move inside Hamarinn volcano. But nothing is confirmed so far. I do not expect anything to be confirmed any time soon.

The harmonic tremor pluses appear on the end of the traces on this image. They are bit hard to spot for the untrained eye. But they appear as higher then background noise change in the tremor plot image.


The harmonic tremor pulse as it appears on the SIL station at Grímsfjall volcano. This is high resolution image from this IMO web page. Copyright of image belongs to Icelandic Meteorological Office.


The harmonic tremor pulse at Skrokkalda SIL station. Copyright of image belongs to Icelandic Meteorological Office.


The harmonic tremor pulse at jok SIL station. Copyright of image belongs to Icelandic Meteorological Office.


Harmonic tremor pulse at dyn SIL station. Copyright of image belongs to Icelandic Meteorological Office.

It is impossible to know what this means exactly. But so far there are no signs of eruption in the area. This activity is less then activity in July 2011 that was created by an minor eruption in Hamarinn volcano. Stronger harmonic tremor pluses appear on SIL station at longer distance. But for now (when active) most of the activity only appears on SIL stations closest to the Vatnajökull glacier. I am going to continue to monitor the current situation. I will update or make a new blog post about what is going on if anything happens.

Posted on

Magnitude 3.2 earthquake on the Reykjanes peninsula

Today (01.09.2012) at 16:33 UTC there was an earthquake with the magnitude of ML3.2. The depth was 7.6 km. Following this earthquake there was an swarm of smaller earthquakes following the first earthquake. None of those have been above magnitude 2.0. The earthquake took place in the Reykjanes volcano most likely. But it appears tectonic in nature. Rather then volcanic.


The magnitude ML3.2 earthquake on the Reykjanes peninsula. Copyright of this image belongs to Icelandic Meteorological Office.

It is hard to know for sure if this activity is going to continue. But since this earthquakes. Activity in this area has stopped. But it might resume at later time.

Icelandic news about this earthquake

Jarðskjálfti á Reykjanesskaga (Rúv.is)
3,2 stiga skjálfti við Grindavík (mbl.is)