Day: August 12, 2014

Posted on

Intra-plate earthquakes in north west Iceland

During the night of 12-August-2014 several intra-plate earthquake took place in north west Iceland. Largest earthquake in this swarm had the magnitude of 1,5. This earthquake activity did appear poorly on my geophone in Böðvarshólar. That is due to distance and small magnitude of the earthquakes, but my geophone at Böðvarshólar did detected this earthquake activity and from that I know that more earthquake activity took place than appears on Icelandic Meteorological Office maps.

140812_2130
The earthquakes in north west Iceland (yellow). This are intra-plate earthquakes. Copyright of this image belongs to Icelandic Meteorological Office.

This earthquake activity is not connected to any known fault zone or any known faults. That however does not mean they are not there. It is impossible to know if there is going to be more earthquake activity in this region. This is however second time this year a earthquake swarm takes place in this area, last one took place in week 28 (in Icelandic). That week the largest earthquake had the magnitude of 1,6.

Posted on

Minor earthquake swarm in Krísuvík volcano

Yesterday (11-August-2014) a minor earthquake swarm took place in Krísuvík volcano. The largest earthquake in this minor earthquake swarm had the magnitude of 3,4 with the depth of 4,4 km. Only few minor earthquakes took place after the largest earthquake.

140811_2100
The earthquake swarm in Krísuvík volcano, the green star shows the location of the magnitude 3,4 earthquake. Copyright of this image belongs to Icelandic Meteorological Office.

There is a risk of more earthquake activity in this area. Since earthquake swarms are known to start with minor activity that slowly grows until it tops and then slowly drops over a period of days or weeks. It might not happen now, but this is a common pattern on the Reykjanes.