Moderate Earthquake Recorded At Iceland's Katla Volcano

There has been increase in seismic activity in the vicinity of Iceland's largest volcano, but scientists say there are no signs yet of an impending eruption.

Katla, which has not erupted since 1918, is located close to Eyjafjallajökull which caused travel chaos across much of Europe when it erupted in April and May 2010.

A magnitude 3.8 earthquake was recorded underneath Katla on Friday evening.

Well-known Icelandic volcano blogger Jon Frimann said: "Today at 15:48 UTC there was an magnitude 3.8, at the depth of 0.1 km in Katla volcano. This earthquake took place on the caldera rim in Katla volcano. No major harmonic tremor was detected following this earthquake. However, some harmonic tremor was detected but it was minor. This might have been hydro-thermal-activity or magma on the move. It is impossible to know for sure what is the case now."

Most recent earthquakes at Katla. Image Icelandic Met Office
Twenty eruptions have been documented at Kalta between 930 and 1918, at intervals of 13–95 years. It has not erupted violently for 94 years, although there may have been small eruptions that did not break the ice cover, including ones in 1955 and 1999.

Prior eruptions have had a Volcanic Explosivity Index (VEI) of between 4 and 6 on a scale of 0 to 8. In comparison, the Eyjafjallajökull 2010 eruption had a VEI4. The bigger VEI6 eruptions are comparable to Mount Pinatubo's 1991 eruption.
Katla eruption 1918
The last significant volcanic eruption in Iceland was that of Grímsvötn on 21 May 2011. The eruption of the basaltic volcano began with 12 km (7 mi) high plumes accompanied by multiple earthquakes, resulting in cancellation of 900 flights in Iceland, and in the United Kingdom, Greenland, Germany, Ireland and Norway on 22–25 May. Until 25 May the eruption scale had been larger than that of the 2010 eruption of Eyjafjallajökull. The eruption paused 25 May 2011, although there was some explosive activity from the tephra vents affecting only the area around the crater.