Eruption Cycle Near Grindavík Could End Soon

gígur, crater, eruption, eldgos

The current volcanic eruption in Sundhnúkagígar could mark the end of a string of eruptions in the area near Grindavík, despite now being in its third week and still chugging along.

The eruption began on March 16 and activity remains in two craters in the area, with steady lava flow and no immediate signs of the eruption ending, according to an Mbl.is report. More of the activity is ongoing in the larger of the two craters. Some gas pollution could be detected in Grindavík and Hafnir today.

Magma flowing from deep

However, there are signs that this might be the final eruption in the cycle of volcanic activity which began at the end of last year. Þor­vald­ur Þórðar­son, professor of volcanology at the University of Iceland, told Mbl.is this weekend that activity in Sundhnúkagígar might be coming to a close.

The shallower magma chamber in the area, situated under Svartsengi near the tourist destination Blue Lagoon, which has been closed since the current eruption started, is no longer receiving magma from the eruption, Þorvaldur explains. Therefore, magma from the deeper magma chamber in the area is flowing to the surface. “This could chug on for the next few days,” he said Saturday. “We’re not talking about the eruption ending in the next few hours.”

Activity elsewhere still possible

“I believe that when this eruption stops the activity in Sundhnúkagígar will end,” Þorvaldur added. “That doesn’t mean, however, that there won’t be activity elsewhere. Since this is coming from the deeper magma chamber and crustal uplift has stopped, the process we’ve seen since November 10 is ending. In my estimation, this activity has been connected to magma flowing from the deeper chamber to the shallower one.”

Reykjanes Eruption Imminent As Magma Nears “Threshold”

litli-hrútur reykjanes

Increased seismic activity on the Reykjanes Peninsula suggests an imminent eruption between Hagafell and Stóra-Skógarfell. A volcanologist at the University of Iceland predicts the eruption could start as early as today, potentially marking a continued pattern of frequent eruptions in the area.

Eruption expected over the coming days

Seismic activity near the magma chamber not far from the town of Grindavík on the Reykjanes Peninsula has increased, indicating that the volume of magma is reaching its threshold. In an interview with Vísir today, Benedikt Ófeigsson, Director of Seismology at the Icelandic Meteorological Office, expressed his concern about people staying in Grindavík but hopes they are ready to leave town quickly.

Speaking to Mbl.is, Þorvaldur Þórðarson, professor of volcanology at the University of Iceland, echoed Benedikt’s concerns, stating that he expected another eruption on the Reykjanes peninsula soon.

“There is no indication that magma is on the move, and the seismic activity we saw last night is likely due to tension in the crust. This, however, tells us that an eruption is close. A threshold is being reached. I said the other day that the eruption would come on March 1, and I’m inclined to stick to that prediction.”

Þorvaldur added that an eruption could begin today or Monday at the latest.

“We are close to having enough magma to lift the lid. We are within those uncertainty margins in terms of volume, and the land uplift has become significant enough that it is in a similar position as it has been before,” Þorvaldur stated, noting that all signs were pointing to an eruption between Hagafell and Stóra-Skógarfell. “However, it cannot be ruled out that a fissure might open further north or south, with the highest likelihood being on the Sundhnjúkar ridge,” Þorvaldur observed.

A pattern that could continue for months or even years

Þorvaldur expects this recent pattern of eruptions on Reykjanes – where eruptions occur every three weeks and last between one to three days – to continue over the next months or even years,

“It is possible that a major earthquake could interrupt this sequence of events, although, in all likelihood, this will simply continue,” Þorvaldur remarked, noting that there have been six eruptions in the Reykjanes peninsula in less than three years.

Þorvaldur suggested that the authorities should consider opening the town of Grindavík, the Svartsengi Power Plant, and the Blue Lagoon more quickly following the next eruption while urging caution and advising against staying or working in these areas when another eruption seems imminent.

As previously noted by Iceland Review, if an eruption were to occur near the Svartsengi area, it would be the fourth eruption since December of last year. It is highly unlikely that such an eruption, as it is confined to a small area on the Reykjanes peninsula, would impact travellers in Iceland.

Reykjanes Eruption Could be Short-Lived, Volcanologist Notes

Reykjanes eruption Iceland eruption

A volcanologist has described the ongoing Reykjanes eruption as typical for shallow magma chamber eruptions, where built-up pressure leads to rapid magma ascent followed by a quick decrease in intensity. The volcanologist also noted that there are indications that the current eruption may be short-lived.

Eruption in Grindavík unlikely

In an interview on the radio station Rás 2 this morning, volcanologist Þorvaldur Þórðarson characterised the ongoing eruption on the Reykjanes peninsula as typical for eruptions originating from a shallow magma chamber, where magma has been injected into a chamber over a significant period of time, causing pressure to build.

“Once that pressure becomes so great that it equals or exceeds the threshold of the chamber’s roof, it breaks, and the magma ascends very quickly. This extra pressure from the accumulation of magma drops rapidly, causing the eruption to decrease swiftly. This is actually a classic example of such eruptions.”

Asked about the likelihood of new vents opening on the fissure as activity diminishes, Þorvaldur believes the chances are “lower than higher.” 

“The risk continually decreases. In my view, there’s almost no chance of an eruption, for instance, in Grindavík, or in its immediate vicinity. However, there’s always a possibility that some craters might reactivate a bit further north. But it seems more likely to go in the other direction.”

Might be over before the weekend

In Þorvaldur’s opinion, it is not unlikely that the area from Eldvörp to Fagradalsfjall might experience more eruptions in the coming years, either on the Sundhnúka rift, along the line in Fagradalsfjall, or possibly slightly westward. “I believe this is not over, unfortunately. There’s an equal chance that we might see a repeat of these events in the coming years.”

When asked to predict the future course of the eruption, Þorvaldur replied that such a thing was difficult. “But many indications suggest that this will be a short eruption that could end within the next few days. Possibly even before the weekend.”

Reykjanes Earthquakes Continue as Concern for Area Grows

Grindavík - Þorbjörn

Conditions have remained unchanged on the Reykjanes peninsula, where recent seismic activity has raised concerns over a new eruption and its potential impact on infrastructure in the area, including the popular tourist destination the Blue Lagoon.

M4.2 Earthquake Near Blue Lagoon

An M3.6 earthquake was recorded near Þorbjörn this morning, a mountain near the town of Grindavík and the epicentre of the recent seismic activity. Several other smaller quakes were recorded during the night, the strongest of which occurred around midnight.

According to the latest monitoring data from the Icelandic Met Office, the land near Þorbjörn continues to rise at the same rate, and there are no clear signs that the magma is approaching the surface. New models have been used to estimate the location of the magma injection point, and these models do not indicate any significant changes in the magma’s position, which is located at a depth of about 4-5 km northwest of Þorbjörn. As magma accumulation continues, increased seismic activity on the Reykjanes peninsula can be expected.

All Possibilities to Be Considered

The recent seismic activity around Þorbjörn, which overlooks the Blue Lagoon, has raised some concern about the popular geothermal spa in the event of an eruption.

Þorvaldur Þórðarson, a professor in geology and volcanology at the University of Iceland, stated in a recent interview that though he didn’t want to make any concrete predictions regarding public safety at this moment, all possibilities should be taken into account.

“We can get lava flows that can travel at several kilometres per hour, even up to 20 kilometres per hour,” he stated to Morgunblaðið.

Given such possible speeds, the response time to an eruption could be very short, Þorvaldur continued. If a fissure opens in the Illahraun lava fields, a lava field just over a kilometre from the Blue Lagoon, the response time could only be minutes.

“If we prepare ourselves for when the magma begins to rise, then, of course, we will have more time,” Þorvaldur stated.

Calls to Close Blue Lagoon

Given the uncertain situation, some have called openly for the Blue Lagoon to close its doors.

In an editorial for Vísir, environmental engineer Sveinn Gauti Einarsson recounted the tragic 2019 Whakaari eruption in New Zealand, in which some 22 people lost their lives. The island is a popular tourist destination known for its volcanic activity and an investigation after the eruption found that owners of the island resort and tour operators may not have fully conformed with health and safety regulations in taking visitors to the area.

In his editorial, Sveinn stated: “Near the centre of the current activity lies the Blue Lagoon, a popular bathing spot. The authorities of the Blue Lagoon have been asked in recent days whether it is safe to bathe in the lagoon. There are no clear answers to that question, but they say that sufficient precautions will be taken to evacuate the lagoon in case of an eruption. Now, I’m not a volcanologist, but I’ve been wondering about this statement. There have been eruptions three times in Reykjanes in recent years, and it was never possible to predict the onset of the eruption, and there were no warnings that the eruption was about to start. How is the situation different now? Why do people trust that they can give several hours of warning even though we were’nt able to at Fimmvörðuháls, the Fagradalsfjall eruption, or in New Zealand? Can it be said with full certainty that an eruption cannot occur there without warning? If a powerful eruption occurs under the Blue Lagoon, it would take only a few seconds to 2-3 minutes for the magma to boil all the water in the lagoon. If people are in the lagoon, there is no time for escape. It would be the greatest tragedy in Iceland in recent times and even worse than in New Zealand.”

The Blue Lagoon currently informs visitors on its website of the increased seismic activity.

Three Routes from Grindavík

An evacuation plan by the Civil Protection for the town of Grindavík, the community nearest the likely eruption site, is now in place. Plans include includes three designated evacuation routes out of the town, evacuation routes within the town, and the locations of major facilities and gathering points.

The evacuation plans are available in Icelandic, English, and Polish

According to authorities, residents are encouraged to prepare for the possible evacuation of the town due to earthquakes or volcanic eruptions. Among other things, residents of the area are encouraged to keep the following in mind:

  • All family members should be informed of the plan.
  • Before leaving one’s house, windows should be closed and electronics unplugged. Basic supplies, such as clothing and medicine, should be prepared in an emergency kit.
  • When leaving one’s house, place a visible note or poster on a window or door notifying neighbours and family.
  • Assist others where possible and drive carefully.
  • Those with extra room in their vehicle should consider helping those on foot.
  • The official meeting point for the community will be the Grindavík sports centre.

In the event of an eruption, more information can be had at the Red Cross helpline: 1717.

 

Reykjanes Eruption Could End With Earthquake Swarm

volcano eruption Geldingadalir Reykjanes

The ongoing eruption on Iceland’s Reykjanes peninsula was kicked off by a strong earthquake swarm, and it could take another such swarm to end it. That’s one of Volcanologist Þorvaldur Þórðarson’s hypotheses about how the eruption could eventually come to a close, but it is indeed just a hypothesis. Experts have oft underlined that there is no reliable way to predict when the eruption will end.

“There are no clear signs that the eruption is ending,” Þorvaldur stated on Bylgjan radio station this morning. Before it began more than three months ago, the eruption was preceded by weeks of strong earthquakes, felt across the capital area and South and West Iceland. Þorvaldur believes another such earthquake swarm could be what stops the eruption, which is located along a rift between two tectonic plates. As the plates move apart, they create tension in the earth’s crust which is released in the form of seismic or volcanic activity.

Read More: The Geology of the Reykjanes Peninsula

“Such plate movements appear to have instigated this eruption and I suspect that maybe something similar is required to end it,” Þorvaldur stated. Until such movement happens, the eruption may continue, and experts have already stated that could be years or decades. Until then, the eruption is “like a pipe that’s always open. It’s dripping steadily. And there’s no tap to screw shut. They forgot to buy one,” Þorvaldur joked in the morning interview.

While volcanic activity at the eruption site briefly paused on the night of June 28, it resumed again some hours later. Þorvaldur says there are once more considerable magma jets spewing from the active crater and visible lava flow over a large area, including Meradalir valley.