Nine Hundred Quakes in Ongoing Earthquake Swarm
An earthquake swarm has been ongoing around Öxarfjörður in northeast Iceland since Saturday. According to Einar Hjörleifsson, a natural disaster expert with the Icelandic Met Office, there have been a total of 900 quakes since the swarm began on Saturday. The swarm is on-going and currently shows no signs of subsiding.
The majority of the quakes have taken place about six kilometres south of the village of Kópasker. Eight quakes have been measured above 3.0 on the Seismic Magnitude scale, the most powerful of which took place at 8:30 pm on Wednesday night and measured 4.2. Thirty seconds later, a quake measuring 3.3 occurred; quakes of 3.3 and 3.2 followed at 9:47 pm and 9:49 pm. Smaller shocks were detected after these larger quakes.
While residents of Kópasker have felt the quakes extremely well, they haven’t been discernible elsewhere, which Einar Hjörleifsson, the Icelandic Met Office’s natural disaster expert, says is normal given the quakes’ size and location. The quakes are taking place along the Tjörnes Fracture Zone, which stretches from all the way up at Grímsey island off of the north coast of Iceland to Landey island just off the coast of Stykkishólmur in Snæfellsnes, West Iceland.
Einar says that the current swarm hasn’t gathered momentum, but it also hasn’t shown signs of losing any, either. The fracture zone has built up a lot of tension and one of two situations is most likely. Either the swarm will slowly fade out, or the built-up tension could cause a larger earthquake, up to 6.0 on the Seismic Magnitude scale. Inhabitants in towns on the north coast of Iceland are advised to make sure all furniture is secure in the case of a larger earthquake and to review the Department of Civil Protection and Emergency Management’s contingency plans.
Kópasker has been the site of numerous powerful earthquakes and earthquake swarms. On January 14, 1976, quakes measuring 5.5 to 6 damaged most of the homes in the village and necessitated the evacuation of women, children, and the elderly. Similar earthquake swarms also occurred in the area in May 1997, April 2007, April 2009, and October 2014.