From Iceland — Mt. Þorbjörn, Volcano In Reykjanes: What You Need To Know

Mt. Þorbjörn, Volcano In Reykjanes: What You Need To Know

Published January 27, 2020

Andie Sophia Fontaine
Photo by
Roman Zacharij/Wikimedia Commons

Plenty of people are talking about Mt. Þorbjörn, an oft-overlooked volcano in southwest Iceland, as the Department of Civil Protection and Emergency Management has declared a “state of uncertainty” regarding recent activity at and around the mountain. What exactly is going on, and what can we expect?

What’s happening

Inflation has been detected just west of Mt. Þorbjörn, on the Reykjanes peninsula, since January 21st, the Icelandic Met Office reports, with a swarm of earthquakes measured just east of the immediate area.

The inflation, scientists studying the area believe, is most likely being caused by an accumulation of magma. Coupled with a nearby earthquake swarm, it is indeed cause for concern. A meeting with residents of the town of Grindavík, located right next to Mt. Þorbjörn, is scheduled for later today.

Caveats

It bears mentioning that magma accumulation does not necessarily mean that an eruption is imminent. Volcanic activity is notoriously unpredictable, and it is entirely possible that nothing comes of this. The earthquake swarm has also decreased in activity recently, and in fact earthquakes in this area are not unusual.

Further, it must be emphasised that there is no such thing as a volcano being “overdue” for an eruption. That is not how volcanoes work. Mt. Þorbjörn last erupted in 1211 and lasted roughly until 1240, but that is by no means an indication that the volcano is on some kind of regular schedule to erupt.

Possible outcomes

Scientists are closely monitoring the situation, and there are a number of possible scenarios for what happens next, depending on whether the inflation is being caused by magma accumulation or not.

As the Met Office details, if the inflation is due to magma accumulation, the possible scenarios that could play out are:

• Magma accumulation will cease soon without further activity.
• Magma accumulation continues for some time without further activity.
• Magma accumulation will lead to a magma intrusion.
• Magma accumulation will lead to magma intrusion and eruption (effusive fissure eruption).
• Magma accumulation triggers seismic activity with larger earthquakes (up to M6.0).

If the inflation is not being caused by magma, then it might be connected to tectonic activity and may lead to larger earthquakes.

All this being the case, while the situation is being taken seriously and being monitored closely, there is as yet no cause for panic.

Support The Reykjavík Grapevine!
Buy subscriptions, t-shirts and more from our shop right here!

Show Me More!