Here is a quick look at the earthquake swarm in Tungnafellsjökull volcano this morning. This earthquake swarm is interesting, as it started with few earthquakes at the depth of around 10 km. This suggests that magma might be pushing up to the volcano at depth now. So far this is not any high volume in my option, at least not enough to start an eruption now. But if this progress continues, it is going to end with an eruption one day. But when and how big is impossible to know at current time. for the moment the earthquakes have stopped. But it is my opinion that this a dike intrusion, not tectonic earthquakes. This can be seen how the earthquakes line them self up from 12.6 km depth and up to 3.6 km depth in almost straight line based on there location.
The earthquake swarm in Tungnafellsjökull volcano. Copyright of this picture belongs to Iceland Meteorological Office.
The earthquake swarm is dense, but that suggests an magma dike intrusion from deep within the volcano. Similar earthquakes have been seen in other volcanoes, like Esjufjöll, Askja, Katla so few are mentioned. So I know this pattern when I see it.
The earthquake pattern as it did appear on Skrokkalda SIL station. The tremor chart shows that the earthquakes where high-frequency earthquakes for most part. Something like that was seen in Eyjafjallajökull volcano before it erupted (it had earthquakes like that many years before it erupted, not just few weeks before). Copyright of this picture belongs to Iceland Meteorological Office.
I did record the largest earthquake on my geophone at Hvammstangi and at Heklubyggð. Based on that trace, the earthquake was noisy. Given me even more clues that support my suggestion that the earthquake swarm was due to dike intrusion.
Similar dike intrusion events are now taking place in Kverkfjöll volcano. But I am going to write about that tomorrow. But earthquakes in Kverkfjöll volcano have been taking place for several years now, with short and long breaks between earthquake swarms.
Another one.
Sunday
08.04.2012 00:16:17 64.764 -17.807 2.7 km 2.0 90.02 13.1 km ENE of Nýidalur
I am seeing earthquake activity in Skrokkalda SIL station that is not appearing on IMO earthquake list.
Yes it looks like another swarm.
Looks how it’s being read at Kalfafell.
http://hraun.vedur.is/ja/oroi/kal.gif
I hope that there won’t be any issues because I am dealing with a payment issue. But that is due to the Easter break and banks. My money transfer from Iceland did not reach my Danish bank in time and my invoice for the server is due today.
I have asked for a payment delay. But I am not sure if the customer service is open in billing today or over the Easter times. So if an error message pops-up, that is the reason. This issue is going to be fixed after the Easter break.
Please make a note of this.
As you are all aware, over recent weeks there has been significant activity on the Atlantic Ridge to the North and South of Iceland, this has currently died down and the activity in the Vatnajökull area has increased. Askja lake was melting and level changing before there was any EQ’s of any note.
The mantle plume beneath Iceland appears to be centred somewhere between Vatnajökull and Mýrdalsjökull. Sil stations have been showing activity and dike intrusions for some time. What concerns me is the possibility that all this EQ activity in heretofore ‘quiet’ volcanoes is signifying an upward mantle plume push and the dike intrusions are a result of that pressure being pushed outward into all mantle chambers and corridors until there is nowhere else for it to go.
I hate being the pessimist, but using logic alone, I believe the next eruption, whenever and wherever it occurs, will be major. If my theory is right about the plume, then maybe we should be looking for the common central volcano for all the activity in Vatnajökull and Mýrdalsjökull, which would be somewhere around Laki – where there has been no EQ’s recently.
The hot plume pushing magma upwards and filling into dikes into the different volcanoes around Vatnajokull seems to make sense.
Maybe the hot plume is somewhere centered over the fissure zone west of Vatnajokull (but then we ignore that the thickest crust is right under Bardarbunga).
As far as we know, there is no central volcano under Laki. It is a side fissure from Grimsvotn, which is to the northeast.
Why do you suggest that the center of the plume should be under there?Actually most of the magma has been released not there but further north, under Veidivotn fissure. But I believe that magma eventually will find a way up in some volcano in Vatnajokull, and not only in one eruption or place, but probably in a few, as history of Iceland often shows us.
I suggest the plume is there from data I have read on studies of the asthenosphere and lithospere under iceland by several uni’s, there is however a school of thought that there is no plume at all, but the fault in that theory is that then there is no explanation for the level of seismic activity here.
is there a dike intrusion aroud God at katla?
A few more quakes near Hamarinn.