The municipality of Grindavík, located just 33 miles or 53 km southwest of the Icelandic capital Reykjavik, is situated directly above a rising magma chamber. Authorities evacuated the area and its surroundings three days ago, requiring over 3,400 people to promptly leave their homes. Some were allowed to return briefly and in an organized manner to retrieve essential belongings and pets.
The urgency was prompted by an ongoing series of several hundred earthquakes in the region, with 15 of them recently reaching a magnitude of over 3.0 and two surpassing the 4.0 mark. These seismic activities caused significant damage to roads and buildings. Experts from the Icelandic Meteorological Office (IMO) interpret these events as precursors to a potential volcanic eruption and have declared an elevated level of danger.
As of the latest update on November 18 at 15:00 UTC, seismic activity linked to the recent magma intrusion remains consistently high. In the last 24 hours, around 1,700 earthquakes were recorded, with 1,000 of them occurring since midnight. The most significant quake in this period had a magnitude of 2.8 and was located near Hagafell, 3.5 km NNE of Grindavík.
Icelandic Meteorological Office
The volcanic activities have also led to the closure of a major tourist attraction: the renowned Blue Lagoon, an outdoor thermal pool near a geothermal power plant four kilometers north of Grindavík, was shut down last Thursday. Concerns primarily revolve around the release of toxic gases in this area.
Where Is the Affected Area and What Is Going On There?
Grindavík is situated on the south coast of the Reykjanes Peninsula, in the southeast of Iceland. The nearby active area of Fagradalsfjall has recently become an ideal tourist volcano: manageable in size and accessible to individuals with varying levels of curiosity and hiking abilities. The Fagradalsfjall volcanic system erupted in 2021 for the first time in over 6,000 years. Since then, the landscape has been dominated by thick, black lava crusts, smoke, and ash.
In connection with the volcano, there is now a 15-kilometer-long magma corridor underground, extending from the northwest of Grindavík to the Atlantic, as reported by the Icelandic Civil Protection Agency. The largest concentration of magma is believed to be in Sundhnúkur near the Blue Lagoon, 2 miles (3.5 km) northwest of Grindavík. These findings are based on models and data collected in the area on Saturday. Ground uplift detected in recent days through satellite imagery and, notably, the recent swarm earthquakes suggest that the magma chamber is moving towards the surface, as explained by experts.
What Danger Does the Magma Pose?
According to the International Maritime Organization (IMO), the magma chamber is currently situated at a depth of approximately 800 meters. The persistence of this depth is inherently uncertain. If the magma manages to breach the surface, the consequences of this eruption depend on various factors, making their effects challenging to predict. An underwater magma eruption, due to the interaction between water and molten rock, would have a more explosive impact.
An eruption on land, on the other hand, would pose a greater threat to Grindavík and its surroundings with lava fountains and lava flows. The extent of the impact on the location primarily depends on where the magma ultimately reaches the surface.
What Do Experts Expect in the Event of an Eruption?
“I am afraid we are approaching an eruption,” explained the volcanologist Thorvaldur Thordarson from the University of Reykjavik in early November, as reported by the Iceland Monitor. The magma has accumulated at a shallow depth. To reach these regions, it must have less weight. The researcher infers that the magma is likely to be less magnesium-rich and, therefore, “coarser” and rich in gases, which would favor a more intense explosion and high magma flow rates. Similarly, experts from the IMO expressed similar views.
Would Reykjavík Also Be Affected by an Eruption?
Currently, it does not seem likely, with the caveat that the extent and location of an eruption are challenging to predict. The potential eruption area is approximately 20 miles (35 kilometers) in a straight line from the center of the capital, Reykjavík. Significantly closer and thus more at risk appears to be the international airport Keflavík, located about 12 miles (20 kilometers) northwest of the active zone.
However, experts from the Icelandic Meteorological Office (IMO) believe that an eruption would not trigger chaos in air traffic, at least not to the extent seen in the eruption of Eyjafjallajökull in 2010. Back then, the combination of lava and glacier ice led to a much more intense eruption. Massive ash clouds in the atmosphere affected European air travel for weeks.
Can the Situation Calm Down Again?
The experts, including Dave McGarvie from the University of Lancaster, United Kingdom, also consider it possible that the magma may not reach all the way to the surface, resulting in no eruption. The best-case scenario, according to the volcanologist, would be if the 9.3-mile-long (15 km) magma tunnel in the depths settles down, literally cools off, and slowly solidifies.
What Is the Situation There at the Moment?
The International Maritime Organization (IMO) continuously reports on the events in the volcanic area on its website. Currently, the situation seems to have somewhat calmed. While seismic activity, originating at a depth of two to five kilometers, persists, it is decreasing overall. Satellite data also indicate a reduction in the rate at which the subsurface of the region is deforming.
There Is Also Rumbling Underground in Italy – Is There a Connection?
A connection is hardly to be assumed. The volcanoes of Italy owe their existence to the subduction of the African continental plate beneath the European one. On the other hand, the volcanic areas of Iceland represent one of the few parts of the Mid-Atlantic Ridge that rises above the sea surface.
Concerns arise in Italy regarding the Phlegraean Fields near Naples. In the area, there have been numerous earthquakes lately, and for months, the region has been uplifting, displaying other signs of increased activity. In recent days, further south in Sicily, Mount Etna has also displayed its fiery nature. Lava fountains and towering clouds of magmatic gases and ash have recently erupted from the crater of Europe’s largest active volcano (height: 11,000 feet – 3,357 meters).
Ash rain fell on several cities in the surrounding area. However, there was no danger to the population, as the authorities announced. Mount Etna is considered a relatively “gentle” volcano, which does not explode like Mount Vesuvius near Naples but regularly releases pressure in smaller doses. The last time this occurred was in the winter of 2020/21. By Monday, Mount Etna had already calmed down again.
References
- Featured Image: Grapevine.is.
- Isländische Meteorologischen Behörde IMO: The newly activated graben at Grindavík remains active
- Update from Reykjanes peninsula
- Was hat es mit der Vulkanaktivität in Nord- und Südeuropa auf sich? – Natur – derStandard.at › Wissenschaft
- Iceland volcano: What’s going on and what are the risks? | CNN
