Minor earthquake swarm in Esjufjöll volcano

Today (27-November-2013) an minor earthquake swarm took place in Esjufjöll volcano. This earthquake swarm was just three earthquakes according to Icelandic Meteorological Office website. There is a chance of more earthquakes not being detected due to bad weather in this area at the moment.

The three earthquakes in Esjufjöll volcano. Copyright of this image belongs to Icelandic Meteorological Office.

The largest earthquake in this minor earthquake swarm had the magnitude of 1,8 and had the depth of 4,5 km. Last eruption in Esjufjöll volcano was possibly in the year 1927, but it is not confirmed according to Global Volcanism Program.

Conductivity spike in Skjálftandafljót glacier river

Last week there was an conductivity spike in Skjálfandarfljót glacier river. It is not clear what did create this conductivity spike that was detected and it’s unknown what volcano or hydrothermal area was leaking water into the river. No glacier flood did follow this spike and no extra activity was detected following this. This conductivity spike was detected on the Thursday 22-November-2013 at 20:20 UTC.

Harmonic tremor detected in Þórðarhyrna volcano

On the 21-November-2013 there was an earthquake swarm in Þórðarhyrna volcano (part of Grímsfjall volcano). This was not large earthquake swarm or a strong one. With the largest earthquake just having the magnitude of 1,9. While I did just suspect it I did not have it confirmed until today that following this earthquake swarm was an harmonic tremor pulse. This harmonic tremor lasted from 03:30 to 06:10 UTC. Based on nearby SIL station this was not a strong harmonic tremor, but this is important because it suggests that something is taking place in Þórðarhyrna volcano. If this is going to lead to an eruption is unknown at current time. This might be a dike intrusion into the volcano at depth, but that has not been confirmed.

The harmonic tremor pulse can be seen at 21-November date on this tremor plot from Icelandic Meteorological Office. Copyright of this image belongs to Icelandic Meteorological Office.

The harmonic tremor pulse as it did appear from Grímsfjall SIL station. Copyright of this image belongs to Icelandic Meteorological Office.

Harmonic tremor pulse as it did appear on Jökulsel SIL station. Copyright of this image belongs to Icelandic Meteorological Office.

This activity might not lead to an eruption, but given the past history of this area and the eruption in Grímsfjall volcano in the spring of 2011 I find it to be highly likely outcome that eruption is going to take place in Þórðarhyrna volcano in near future, it is not possible to know when such eruption might take place. Last eruption took place in Þórðarhyrna volcano in the year 1902, it is not known if any later eruptions have taken place in Þórðarhyrna volcano.

Blog post updated at 14:47 UTC.