Shawn Willsey published November 10, 2023:Iceland Town Ordered to Evacuate! Geologic Update by Geology Professor. A second and much needed Nov 10, 2023 update from geology professor Shawn Willsey. We will look at how seismic data changed during day, including the earthquake swarm that developed under the town of Grindavik, which was recently placed under a mandatory evacuation order. Possible outcomes of this ongoing situation are also discussed. Stay strong, Grindavik!
Fox Weather
written by Hillary Andrews
Friday November 10, 2023
GRINDAVIK, Iceland – Officials have urged residents of a town on Iceland's coast to evacuate Friday as the alert for the Reykjanes volcanic system near Reykjavik was elevated to orange, according to local officials.
An Orange alert means that the volcanic system is showing heightened unrest with increased likelihood of eruption, said the Iceland Met Office. They added that the most likely scenario is that it will take several days for magma to reach the surface.
"In case the current intrusion will evolve further and magma will start propagating towards the surface in this area, the most likely outcome would be an effusive eruption," the Iceland Meteorological Agency said. "However, the presence of shallow ground-water in the vicinity of the ongoing magmatic accumulation, might trigger some short-lived explosions whenever magma will encounter these reservoirs."
Officials said that while there is no immediate danger, residents of Grindavik have been asked to evacuate as a precaution.
This comes after the island nation's famed Blue Lagoon experienced 1,400 earthquakes in 24 hours as of Thursday, causing the lagoon to temporarily close and rattling the nerves of resort guests.
The wellness spa resort is based around a lagoon of geothermal heated seawater which harnesses the power of the nearby Fagradalsfjall volcanic complex.
"Blue Lagoon has proactively chosen to temporarily suspend operations for one week, despite the authorities not raising the current level of uncertainty during this period of seismic activity," the resort said in a statement. "This affects all of our operations: Blue Lagoon, Silica Hotel, Retreat Spa, Retreat Hotel, Lava and Moss Restaurant."
A whole lot of shaking
The earthquake activity recently ramped up after starting on October 25, according to the Icelandic Met Office. In all, local media reports that 22,000 quakes have shaken the Reykjanes Peninsula. Seven of the temblors measured above magnitude 4.0, with the strongest hitting just after midnight Thursday of magnitude 4.8.
"The seismic activity last night and this morning is an example of this episodic seismic activity that can be expected while magma accumulation is in progress," wrote the IMO. "The fact that there are now larger earthquakes than before in the area does not necessarily mean an increased rate of magma accumulation."
News reports about the seismic activity have shaken prospective guests, including an American family traveling in Iceland that decided to steer clear.
"We were all very aware of the earthquake/volcano situation," Chase Nunes, who was vacationing in Iceland, told FOX Weather. "We moderately thought about going there (to the lagoon). However, once we heard about the rocks going into the lagoon and some tour operators refusing to go there, that was our cue to avoid that area."
Quakes may signal volcanic eruption
Magma is pooling in what the IMO called an "inflation event."
On Friday, they noted that the seismic activity currently measured at Sundhnjúkagígar occurs within an area about 3 km northeast of Grindavík. The most likely scenario now, taking into account the activity that culminated in the onset of the March 19, 2021 eruption, is that it will take several days (rather than hours) for magma to reach the surface.
Starting October 27, the molten rock began accumulating in a horizontal sill about 3 miles below the surface, forcing the earth up or inflating it. The office estimated that the magma inflow is 176 cubic feet per second. That is enough to fill up an Olympic-sized pool every eight minutes.
The Department of Civil Protection and Emergency Management declared a Civil Protection Service Level of Uncertainty due to the earthquakes. The level of uncertainty means increased monitoring of the situation that could lead to a threat to the health and safety of people, the environment or the settlement.
"A series of earthquakes began earlier this week and is still ongoing," stated the visitors' bureau's website. "This does not mean that an eruption is imminent, but the area is being closely monitored for any changes. Visitors and hikers are encouraged to stay away from mountains and slopes in the area due to the danger of rockfalls and landslides."
The site noted that the increased quake activity is similar to the events before the eruption of Mt. Fagradalsfjall last year and this summer.
The IMO noted that the magma inflow on Monday was four times greater than the highest inflow during the previous inflation events.
"Signs of magma coming towards the surface would appear as increased, shallower seismicity and rapid crustal deformation at the surface as well as volcanic tremor, which is a high rate of many small earthquakes," wrote the IMO on Nov. 4. "At the moment no clear signs can be seen of any of this, but the situation can change on short notice."
This summer's eruption was part of the Fagrandalsfjall volcano area, which previously erupted in August 2022 and March 2021. Before then, it was considered to be dormant for more than 6,000 years.
The Reykjavík Grapevine published November 10, 2023 BLUE LAGOON: Volcano Watch 2023: What The Heck Is Happening By The Blue Lagoon?
Tens of thousands of earthquakes have rattled the Reykjanes peninsula since October 27, 2023, and GPS readings show ground uplift and magma accumulating 4km underground. What makes this different from the similar events in 2021, 2022 and July 2023? It's all happening right by the Blue Lagoon, the town of Grindavík and the Svartsengi Power Plant.
The Reykjavík Grapevine's Jón Trausti Sigurðarson visited the seismically active area with volcanologist Þorvaldur Þórðarson on Nov. 8, 2023, to find our what's going on.
Reykjavik Grapevine
written by Staff
Friday November 10, 2023
The Icelandic Met Office reports that a dike formation has likely formed beneath the town of Grindavík. With the magma intrusion possible extending beneath the town with a population of 3,700 a mandatory evacuation has been ordered.
Part of the met office’s update on the matter is below:
The seismic activity has moved south towards Grindavík. Based on how the seismic activity has evolved since 6 PM today, along with results from GPS measurements, there is a likelihood that a magma intrusion has extended beneath Grindavík.
The Department of Civil Protection has raised their alert level to an Emergency/Distress Phase (Neyðarstig). Here is what that means:
Emergency phase is characterized by an event which has already begun and could lead, or already has led to, harm to people, communities, properties or the environment. At this stage, immediate measure are taken to ensure security, save lives and prevent casualties, damage and or loss.Mobile phone alerts. In the case of disasters or emergencies the Civil Protection sends out alerts to mobile phones in the affected area using cell broadcasting via cell towers. The alert will be broadcast to areas affected by serious disasters. Most capable devices entering the area during the cell broadcast should receive the alert. If your phone is on, capable and inside the targeted location, you should get the alerts. You don’t have to download an app or subscribe to a service, just ensure your phone is capable and updated. You will not be able to respond to the message. In case of an emergency please call 112.
UPDATE: Nov. 10, 2023 — 23:25
Director of Civil Protection Víðir Reynisson Is delivering a live television update at the time of writing and has announced the mandatory evacuation of the town of Grindavík to happen tonight.
He stresses that residents must leave town in the next two to three hours.
Víðir clarified for reporters that this is not an “emergency evacuation,” which would require the town to be vacated within 30 minutes.
Evacuating residents are told to turn off the electricity in their homes and close all windows when leaving. They are further asked to post a paper on the door or street-facing window indicating that the home has been evacuated.
UPDATE: Nov. 10, 2023 — 23:00
Authorities are ready to evacuate Grindavík. The Icelandic Met Office said that the situation is developing quickly.
Víðir Reynisson will be delivering a live update from the Department of Civil Protection and Emergency Management shortly.
UPDATE: Nov. 10, 2023 — 22:15
The Department of Civil Protection and Emergency Management has launched a page with information in Icelandic, English and Polish to keep people informed about the situation on the Reykjanes peninsula.
It can be found here: https://reykjanes.almannavarnir.is/en
UPDATE: Nov. 10, 2023 — 21:10
The Icelandic Met Office has measured signs that a lava tunnel is forming toward the surface at Sundhnúkar. However, an eruption has not begun.
This information was shared in the latest alert from the Department of Civil Protection and Emergency Management, translated in full below:
Very clear signs are now appearing on the Met Office’s gauges of the formation of a magma tunnel toward the surface. The highest probability remains that magma will emerge north of the watershed at Sundhnúkar and, according to the lava flow model conducted earlier this evening, lava will not flow to Grindavík.More information is not available at this time, but will be updated as soon as it is available.HS Orka requests that Grindavík residents to call HS Veitur at 422 5200 if they experience flickering electricity.
UPDATE: Nov. 10, 2023 — 20:30
National broadcaster RÚV reports that trucks are on site and build defences around HS Orka’s Svartsengi power plant and the town of Grindavík. The berm will be 4 km long and six to eight metres tall, according to the Department of Civil Protection and Emergency Management.
UPDATE: Nov. 10, 2023 — 20:15
The Department of Civil Protection and Emergency Management has made an announcement on the likelihood of an eruption at Sundhnúkar.
The signs that can be seen now at Sundhnúkar are similar to those seen on the eve of the first eruption at Fagradalsfjall in 2021 and are very similar to the seismic activity that was measured about a month before the eruption.Looking at the sequence of events that ended in the March 19, 2023, eruption — and though the seismicity is not significantly deepening so far — we are probably looking at several days rather than hours before magma reaches the surface.If a crack were to appear where the seismic activity is highest now, lava would flow to the southeast and to the west, but not towards Grindavík. Civil Defense ran a lava flow model this evening, based on the most likely location of an eruption. That model does not indicate that lava will flow towards Grindavík.This evening, Civil Defense requested that the Coast Guard deploy its patrol vessel Þór to Grindavík for security purposes. Þór has departed Reykjavík and is expected to arrive in Grindavík tonight.Aid stations will be opened in the next hour (this is written at 19:50) in Grindavík sports hall, the Sunnubraut sports hall in Reykjanesbær, Vallarskóla in Selfoss, and at Krónan in Kópavogur. In Grindavík, the station is only for collection and information and if people need help going elsewhere. Refreshment, information and accommodation if necessary will be available to those who seek it.Attention is drawn to the fact that Grindavíkurvegur is currently closed due to damage. People are advised to take Suðurstrandarvegur on their way to Selfoss and Reykjavík or Nesvegur if they choose to go to Reykjanesbær. Repairs on Grindavíkurvegur are ongoing and information will be provided if and when Grindavíkurvegur will be reopened.
UPDATE: Nov. 10, 2023 — 19:22
Director of Civil Protection Víðir Reynisson told the TV station Stöð 2 this evening that there is currently no reason for residents of Grindavík to leave town and that there are no signs currently that an eruption has begun, Vísir.is reports.
Grindavík has been shaking incessantly for three hours.
Víðir told the station that roads have been damaged by the earthquakes, and cracks have formed in some houses.
“This could be the start of the process we’ve been waiting for, of magma making its way to the surface, but there’s still no evidence of that happening yet,” he said.
According to rescue teams Grindavík residents are leaving town. Grindavíkurvegur remains closed, but could be opened in the coming hours.
UPDATE: Nov. 10, 2023 — 18:51
The location of the increased seismic activity is centred on Sundhnúkagígar, a row of craters just north of Grindavík that last erupted in the Reykjanes fires that lasted from the years 950 to 1240.
When speaking with the Reykjavík Grapevine on Wednesday, volcanologist Þorvaldur Þórðarsson said the volcanic lineament Sundhnúkar would be the worst place for an eruption to take place, due to the short distance from that lineament to the Svartsengi power plant.
The southern end of that existing lineament is just 1 km from the town of Grindavík.
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