[ACTUEEL] Vulkanen IJsland #27: Uitbarsting Reykjanes

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Steady eruption near Grindavík, Iceland

Eruptive activity near Grindavik, Iceland, remains steady on November 28, 2024, with the eruption continuing from a single vent and lava flowing east and southeast. Gas pollution caused by northeast winds at 35 – 55 km/h (20 – 35 mph) was moving toward Grindavík today and was forecast to spread to nearby areas as the weather patterns change.

The fissure opening around midnight taken from the Coast Guard helicopter. Lights in the town of Grindavík seen in the distance on November 28, 2024. Image credit: Civil Protection/Björn Oddsson

Eruptive activity near Grindavik has been steady over the last 24 hours, with lava now flowing predominantly east and southeast, towards and along the base of Fagradalsfjall, the Icelandic Met Office (IMO) reported at 15:50 UTC on November 28.

The lava field near Fagradalsfjall has expanded slightly but continues to thicken.

Volcanic tremor has remained stable alongside eruptive activity in the vent while the rate of subsidence around Svartsengi has significantly reduced.

However, because daily changes are minor, the trend of deformation measurements must be monitored over the next several days to determine whether the uplift has resumed.

Reykjanes Peninsula, Iceland molten lava approaches infrastructure on November 21, 2024
Molten lava approaches infrastructure, Reykjanes Peninsula, Iceland on November 21, 2024. Image credit: IMO
The eruption site has been limited to a single active vent of Stóra-Skógfell with lava flowing eastward. Flows beneath the solid crust have been found near the protective wells at Svartsengi and the Blue Lagoon geothermal spa.

The eruption tremors have stabilized and the ground subsidence around Svartsengi has slowed down on November 28.

On November 27, IMO issued an updated hazard assessment, valid until 15:00 on November 29, assuming no significant changes. Based on the eruption’s development over the past few days and the gas dispersion forecast, the hazard assessment has been revised from the previous version.

The main changes involve Zone 1 (Svartsengi), where the overall hazard level is now assessed as considerable (amber) instead of high (red), and Zone 4 (Grindavík), where the overall hazard level has been downgraded from considerable (amber) to moderate (yellow).

In Zone 1 (Svartsengi), the risk of lava flow and gas pollution remains high, but the risk of tephra fall has been downgraded to moderate from considerable.

For Zone 4 (Grindavík), the only change is that the risk of gas pollution is now assessed as “considerable,” down from “very high.” According to the gas dispersion forecast, there is a likelihood of gas pollution in Grindavík on November 29.

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Earthquake swarm on Reykjanes Ridge, Iceland

A strong earthquake swarm was registered on Iceland’s Reykjanes Ridge between December 28 and 30, 2024. The activity was concentrated in a tectonically active area, with the strongest reaching M3.6.

The Icelandic Met Office (IMO) registered a total of 258 earthquakes on or near Reykjanes Ridge in 48 hours to 20:15 UTC on December 30, 2024, with activity concentrated around Eldey and nearby locations.

Out of the total events, 104 earthquakes had a magnitude below 1. These smaller quakes often go unnoticed by residents but are critical in understanding the ongoing seismic processes in the region.

Another 137 earthquakes registered between magnitude 1 and 2, accounting for the majority of the seismic events.

Fifteen earthquakes were recorded with magnitudes ranging between 2 and 3, which are typically strong enough to be felt locally.

Two earthquakes exceeded magnitude 3, with the strongest quake of magnitude 3.6 occurring at 13:55 UTC on December 29, at a depth of 9.9 km (6.1 miles) and located 3.7 km (2.2 miles) north-northeast of Eldey.

The recent seismic activity is attributed to tectonic movements along the Mid-Atlantic Ridge where the Eurasian and North American tectonic plates diverge.

“They are moderately powerful, with two measuring above magnitude 3 and several others just below that, occurring both early this morning and later in the afternoon,” Böđvar Sveinsson, a natural hazard specialist at the IMO noted.

“This is likely due to tectonic plate movements, but so far, there are no signs of volcanic tremor,” Sveinsson added.
The region is a part of the Reykjanes volcanic system and is known for frequent seismic and volcanic activity because of its location along the Mid-Atlantic Ridge. The system includes numerous postglacial basaltic crater rows and small shield volcanoes.

The Reykjanes volcanic system has a long history of eruptions with 20 confirmed Holocene eruptive periods. Historical records include events as recent as the 13th century with eruptions along NE-SW fissure systems forming new craters and lava flows. Submarine eruptions have also been observed occasionally forming ephemeral islands.

Major eruptions include the Campanian Ignimbrite eruption around 36 000 years ago and the Neapolitan Yellow Tuff eruption 15 000 years ago.

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Op dinsdag 14 januari 2025 14:18 schreef Momo het volgende:
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Bardarbunga volcano (Iceland): strong seismic swarm, likely magma intrusion, alert raised

A strong earthquake swarm has started under the volcano this morning at around 6 a.m. local time. More than 100 quakes with magnitudes up to 5.0 have been recorded since. The strongest quake was a 5.0 shock at 08.05 am local time.
The quakes are clustered under the northern part of the large, completely ice-covered Bárđarbunga caldera, and located at depths spanning between 10 km and the surface. This is the strongest seismic activity of the volcano since the preceding seismic activity prior to its massive eruption in 2014-15. The activity closely resembles the pattern of a new magma intrusion, which is likely the cause.
This could (but by no means must) result in a new eruption, even in a very short term. If the eruption starts under the ice shield (where the current intrusion is taking place), it would result in potentially dangerous glacial melt-water floods (known as "jökulhlaups"). It also could lead to significant ash emissions once the erupted lava has melted a hole through the thick ice shield, and allows explosive interaction between magma and water to eject ash into the atmosphere - this in turn would depend on the duration and volume of such eruption.
While it is far from certain what might or might not follow, the aviation alert level of the volcano was raised to yellow and a "Level of Uncertainty" was declared for Bárđarbunga by the Civil Protection. As of the latest information available, activity has slowed during the past few hours.

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Glacial outburst flood at Grímsvötn volcano, Iceland

Seismic readings indicated the onset of a glacial outburst flood from Grímsvötn volcano on January 13, 2025. Grímsvatn floods have occurred almost annually since November 2021. There are examples of volcanic eruptions occurring due to pressure relief in Grímsvötn after water gushes from there. However, glacial outburst floods have occurred much more frequently without volcanic eruptions.

A glacial outburst flood began on January 13 at Grímsvötn, one of Iceland’s central and highly active volcanoes situated beneath the Vatnajökull ice sheet.

Seismic activity on Grímsvötn has been rising steadily in recent days which signaled the movement of water beneath the glacier. The floodwaters flow from Grímsvötn through Skeiđarárjökull and enter Gígjukvísl, a glacial river south of the glacier.

The turbulence graph from Grímsfjall shows consistent growth in seismic signals within the 2 to 4 Hz frequency range.

“The Institute of Earth Sciences’ GPS device on the ice shelf in Grímsvötn cannot be contacted, making it more difficult to assess how quickly the water is flowing from the lakes and down the channel under Skeiđarárjökull, but turbulence measurements on Grímsfjall provide indications of the development of the flow,” IMO noted on January 13.

The measurements were combined with hydrological data and indicate that the glacial flood is in its early stages. The current water volume in Grímsvötn is estimated to be approximately 0.25 km3 (0.06 mi3) which is about one-third of the volume recorded before the outburst in 2021.

Past patterns suggest that peak flow rates could occur in the latter half of the week. The maximum water discharge at National Road 1 in Gígjukvísl is projected to reach approximately 1 000 m3/s (35 315 feet3/s).

Experts believe it will not pose a threat to infrastructure such as roads and bridges in the region despite the substantial flow.

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Magma accumulation approches critical volume at Svartsengi, Iceland

Magma continues accumulating beneath Svartsengi at a rate nearing the levels observed before the previous eruption. Deformation measurements confirm ongoing ground uplift, with geophysical models estimating that the subsurface magma volume is approaching the threshold associated with past magma intrusions.

Deformation measurements indicate sustained ground uplift in the Svartsengi region which is consistent with patterns seen before past eruptions.

Modeling calculations estimate that the magma accumulating beneath the area is nearing the amount drained during the last eruption on December 9, 2024. If this trend continues, the probability of a new magma intrusion and subsequent eruption will rise in the coming weeks.

Scientists analyzing previous events have found that once a similar volume of magma builds up, intrusion events tend to occur, often followed by an eruption.

The overall earthquake count remains relatively low while seismic activity in the Sundhnúkar fissure system has been increasing slowly since December 9, 2024, suggesting that the next eruption might not be preceded by seismic activity.

The updated hazard assessment from the IMO reflects the growing magma volume beneath Svartsengi.

Based on magma inflow rates, experts estimate that the subsurface magma volume could reach 12 million m3 (424 million feet3) by late January and potentially 13.5 million m3 (477 million feet3) by early February.

The estimates align with the amount of magma involved in the intrusion event on November 20, 2024, suggesting that conditions for another magma intrusion are becoming increasingly favorable.

The Icelandic Meteorological Office (IMO) has raised the hazard level in Zones 4 and 6 from moderate (Yellow) to considerable (Orange), and adverse weather conditions in the coming days may impact monitoring capabilities. The updated hazard assessment is valid until February 11 unless developments occur.

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Echter volgt op 20 december het bericht dat ook nu de grond in het gebied weer aan het stijgen is en dag magma zich opnieuw beweegt. Men verwacht dan ook dat eind januari of begin februari 2025 er opnieuw een eruptie in het gebied zal plaatsvinden.

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Op woensdag 29 januari 2025 13:14 schreef Frutsel het volgende:

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Uit:
WKN / WKN Jaaroverzicht 2024
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Kan dus elk moment inderdaad gebeuren

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Volcanic eruption risk in Iceland increases, scientists warn

REYKJAVIK, Iceland – Scientists in Iceland say there is an increasing likelihood that a volcano, which has erupted several times since the end of 2023, will spring to life once again as magma continues to build up beneath the Earth’s surface.

The Icelandic Meteorological Office (IMO) said on Friday that the amount of magma accumulating beneath Svartsengi is approaching levels observed during previous eruptions, and the likelihood of a new magma intrusion or eruption is increasing.

Scientists have also been concerned about severe winter weather across the region. According to the IMO, weather could impact monitoring and response in case of a magma intrusion or eruption.

"Strong winds, sleet and snow could interfere with seismic measurements and reduce the accuracy of GPS monitoring of ground lift," the IMO said. "The Icelandic Meteorological Office will continue to closely monitor developments, and people are encouraged to pay attention to weather warnings and exercise caution when traveling."

Scientists say that according to model calculations, magma under Svartsengi has reached the lower boundary of the volume loss that was observed during the last eruption.

"Based on past eruptions, these models suggest that magma intrusions or eruptions tend to occur once this lower boundary is reached," the IMO warned.

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Op maandag 31 maart 2025 13:30 schreef Dr_Flash het volgende:
Gebeurt hier nogeens wat eigenlijk?

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Op dinsdag 1 april 2025 15:39 schreef TARAraboemdijee het volgende:

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Echt hoor, zeg je dit, en nog geen 24 uur later

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Op dinsdag 1 april 2025 19:33 schreef chufi het volgende:
Ja de bevingen gaan maar door 135 laatste uur

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Op dinsdag 1 april 2025 15:39 schreef TARAraboemdijee het volgende:

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Echt hoor, zeg je dit, en nog geen 24 uur later

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Op dinsdag 1 april 2025 15:44 schreef chufi het volgende:

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Het neemt al weer af in hevigheid ... maar misschien komt er meer

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Op dinsdag 1 april 2025 21:16 schreef Peterselieman het volgende:

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Mogelijk andere locatie, want dit stelde niet veel voor