Will It or Will not likely It? Iceland’s Volcano Threatens Eruption

By Stephanie Pappas

Following several tense times of earthquake swarms, people dwelling on Iceland’s Reykjanes Peninsula are in limbo as they hold out to see no matter whether a surging blob of magma about fifty percent a mile (almost a kilometer) beneath their ft will carefully silent down—or explode in a harmful volcanic eruption.

Additional than 3,000 persons been evacuated from the town of Grindavík in southwestern Iceland, which has been ruined by times of relentless quakes. Some of these have opened fissures in the landscape, such as throughout roads. Seismic action experienced quieted as of November 14, geoscientists say, but it is really hard to inform irrespective of whether this is a long lasting trend or the calm ahead of the storm. Past eruptions in the location experienced demonstrated styles of peaceful just before the lava begun flowing. “We never know yet if [the volcano] will erupt,” claims Vincent Drouin, a team scientist at the Icelandic Meteorological Office (IMO), who specializes in checking the landscape. “We’re attempting to look for smaller signals.”

The Reykjanes Peninsula is home to the famous Blue Lagoon warm spring, which on a regular basis draws travelers from all over the world and is now shut because of the hazard. The region’s geology has been restless for many months, Drouin suggests, with seismic displays and GPS stations exhibiting the floor inflating—a sign of magma motion down below. And past week, earthquake activity begun kicking up in a huge way. On November 9, for instance, the IMO described that about 1,400 earthquakes have been recorded within 24 hours. The major was magnitude 4.8. Then, on the subsequent afternoon, a relentless swarm of solid quakes shook the peninsula. “This was incredible,” suggests Dave McGarvie, a volcanologist at Lancaster University in England, who research Icelandic eruptions. “I really do not assume I’ve noticed just about anything like this in Iceland in advance of.”

The cause for the temblors was a huge underground river of magma that quickly shot out from a temporary reservoir referred to as a “sill,” the place it experienced been accumulating about 2.5 miles (4 km) down. As it surged out of the sill, it formed a 9.3-mile-prolonged (15-km-extensive) intrusion, or dyke. This dyke now sits about .5 mile (800 meters) down below the surface, according to the IMO. If there is an eruption, it will likely take place someplace together the dyke.

“What stunned people today in this article is the pace of factors taking place,” states Sigrún Hreinsdóttir, a senior geodetic scientist at GNS Science in New Zealand, who has researched the location of the Reykjanes Peninsula. Some seismic stations in the area showed the ground subsiding much more than a few feet (1 m) in a subject of hours as the magma moved, she states.

Authorities declared a point out of crisis and requested the evacuation of Grindavík on Friday night. By Tuesday, Drouin suggests, seismic exercise experienced slowed somewhat, but the IMO has continue to detected additional than 700 tiny earthquakes along the intrusion considering that midnight nearby time.

The peninsula’s geology is contributing to the sizing of some of those people quakes, Hreinsdóttir says. Iceland sits in excess of a volcanic hotspot, wherever magma arrives close to the surface area. The island nation is also appropriate on leading of the Mid-Atlantic Ridge, the boundary in which the North American and Eurasian plates are slowly and gradually pulling away from each other. The Mid-Atlantic Ridge is largely underwater but arrives onshore on the heel of the Reykjanes Peninsula. “We have equally a seismic zone and volcanic methods,” Hreinsdóttir suggests.

She clarifies that while the movement of the magma itself would make the floor shudder, the subterranean modifications wrought by this motion also change the strain on many faults in this seismically active region. Therefore, the magma action is triggering earthquakes on close by faults, and these quakes are larger than individuals triggered directly by magma motion by itself.

Presented the region’s wild geology, maybe it is not shocking that this is not the initially time the Reykjanes Peninsula has rumbled to lifetime. Every single 1,000 yrs or so the space goes by way of periods of volcanic action that just about every previous 200 or 300 decades, Hreinsdóttir suggests. The very last time that took place was between the 10th and 13th generations. Not many data survive from that time, so it’s tough to use that occasion to forecast what will transpire in the foreseeable future.

“Each time you make a new eruption, you make new magma you adjust the devices,” Drouin states. “So it will not be the very same as final time.”

Hreinsdóttir says that it does seem to be that a new period of time of volcanic activity is dawning, nonetheless. In 2021 other volcanic programs on the peninsula manufactured 4 magma intrusions. A few of people finished in eruptions, albeit small ones in unpopulated locations.

If the most current unrest does direct to an eruption, it will not be probable to direct to the popular airline cancellations that occurred in 2010 when the Icelandic volcano Eyjafjallajökull erupted. That volcano pumped volcanic ash more than 5.6 miles (9 km) into the ambiance, seriously disrupting flights in excess of the North Atlantic. The volcanic units on Reykjanes are likely to generate oozy, minimal-gas lava flows with incredibly little ash. The most important danger is likely that lava flows will threaten Grindavík or the Reykjanes Power Station, a geothermal plant close by. Authorities may perhaps dig trenches or earthen dams to redirect any flows away from these areas in the event of an eruption, Drouin states.

“Every working day we consider to reassess, primarily based on the data we have, to see if the dyke is inflating and where by,” Drouin says. “That’s in all probability where it is most most likely to erupt.”