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Earth of fire

Actualité volcanique, Articles de fond sur étude de volcan, tectonique, récits et photos de voyage

volcanic activity

Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
Gunung Ibu - ash plume from 05.16.2022 / 4:46 PM WIT - PVMBG Magma Indonesia webcam - one click to enlarge

Gunung Ibu - ash plume from 05.16.2022 / 4:46 PM WIT - PVMBG Magma Indonesia webcam - one click to enlarge

The Gunung Ibu continues its eruptive phase with, this Monday, May 16, 2022 at 4:46 p.m. WIT, an ash plume observed at ± 2500 m above the summit (± 3825 m above sea level). The ash column is gray and thick, dispersing to the west. This eruption was recorded on a seismograph with a maximum amplitude of 30 mm and a duration of 154 seconds.

Activity level remains at 2 / waspada

Seismology is characterized this May 15 by:

- 49 eruption earthquakes, with an amplitude of 15 to 30 mm and an earthquake duration of 20 to 80 seconds.
- 24 avalanche earthquakes, with an amplitude of 2-3 mm and an earthquake duration of 15 to 65 seconds.
- 2 emission earthquakes, with an amplitude of 5 to 14 mm and an earthquake duration of 10 to 40 seconds.
- 9 harmonic episodes
- 24 shallow volcanic earthquakes
- 2 distant tectonic earthquakes.

 

Communities around Mount Ibu and visitors/tourists are advised not to travel within the 2.0 km radius and the sector expansion is 3.5 km to the crater opening in the northern part from the active crater of Mount Ibu.

 

Source: PVMBG, Magma Indonesia

Sabancaya - activity between 9 and 15.05.2022 - Doc. I.G.Peru - one click to enlarge

Sabancaya - activity between 9 and 15.05.2022 - Doc. I.G.Peru - one click to enlarge

For the week of May 9 to 15, 2022, I.G.Peru reports moderate eruptive activity at Sabancaya, with an average of 54 explosions per day, and plumes of gas and ash reaching 2,500 meters above the summit.

Over the period, 406 earthquakes associated with the circulation of internal magmatic fluids were detected, as well as VT earthquakes linked to the fradturation of rocks.

No significant deformation anomalies. Five thermal anomalies, with a max. of 68 MW have been identified by satellite, in relation to the presence of a lava body on the surface of the crater.

The volcanic alert level remains at naranja, with an inaccessible zone of 12 km radius.

 

Source : I.G.P. Posted on 17.05.2022

Reykjanes Peninsula - location and magnitude of earthquakes on 16.05.2022 / 12:35 p.m. - Doc. IMO
Reykjanes Peninsula - location and magnitude of earthquakes on 16.05.2022 / 12:35 p.m. - Doc. IMO
Reykjanes Peninsula - location and magnitude of earthquakes on 16.05.2022 / 12:35 p.m. - Doc. IMO

Reykjanes Peninsula - location and magnitude of earthquakes on 16.05.2022 / 12:35 p.m. - Doc. IMO

The Icelandic Meteorological Office website says that according to a GPS measurement network on the Reykjanes peninsula and InSAR satellite images, there are records from the Earth's surface that show signs of expansion indicating an accumulation of magma west of Þorbjörn.

Benedikt G. Ófeigsson, an expert in the field of crustal movements at the Icelandic Meteorological Bureau, said in an interview with Víkurfréttir that the GPS station at Þorbjörn has lifted 20 to 30 mm since the beginning of the month and continues to rise. To do.

Michelle Parks @Vedurstofan modeled the ongoing inflation signal at Svartsengi. It's in a similar location to the 3x magma intrusions we had in 2020. This one is slightly deeper (4-5km) and about half the volume compared to each 2020 intrusion. is estimated at 1.5 km³.

Reykjanes Peninsula - interferogram of the Grindavik region (April 21 - May 8, 2022) - Doc. Michelle Parks @Vedurstofan / via K. Jonsdottir

Reykjanes Peninsula - interferogram of the Grindavik region (April 21 - May 8, 2022) - Doc. Michelle Parks @Vedurstofan / via K. Jonsdottir

Aviation code for Icelandic volcanic systems as of 16.05.2022 - Doc. © Veðurstofa Islands

Aviation code for Icelandic volcanic systems as of 16.05.2022 - Doc. © Veðurstofa Islands

In light of signs of magma accumulation and expansion at Reykjanes, the VONA flight color code has been moved from green to yellow.
The National Police Commissioner, in consultation with the Suðurnes Police Commissioner, has declared the level of civil protection uncertainty as of 15 May.

 

Sources : IMO, Oroapuls, mbls

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia

A swarm of earthquakes started near Eldvörp in the Reykjanes Peninsula at 11:30 a.m. yesterday, May 15, 2022.

At 5:38 p.m. an M4.7 occurred, 2:17 p.m. an earthquake of M4.2 in this area, the earthquake was felt. At 11:35 an M3.5 occurred. Another M3.7 earthquake occurred at 12:01 p.m.

Landslides can occur on the slopes and sides of mountains when earthquakes of these magnitudes occur. Caution is advised for people in these areas.

At 4:56 p.m. on Saturday, a magnitude 4.8 earthquake occurred in Þrengslin east of Lambafell at a depth of 8 km. The earthquake was felt in southern and western Iceland. Aftershocks can be expected

Eldvörp - photo archives Iceland Mag - one click to enlarge

Eldvörp - photo archives Iceland Mag - one click to enlarge

Eldvörp craters - by Rafn Sigurbjörnsson

Reykjanes peninsula - seismic swarm as of 05.15.2022 / 6:45 p.m., location and magnitude - IMO - click to enlarge
Reykjanes peninsula - seismic swarm as of 05.15.2022 / 6:45 p.m., location and magnitude - IMO - click to enlarge
Reykjanes peninsula - seismic swarm as of 05.15.2022 / 6:45 p.m., location and magnitude - IMO - click to enlarge

Reykjanes peninsula - seismic swarm as of 05.15.2022 / 6:45 p.m., location and magnitude - IMO - click to enlarge

Reykjanes peninsula - seismic swarm on 15.05.2022 - Doc. IMO

Reykjanes peninsula - seismic swarm on 15.05.2022 - Doc. IMO

A possible area to monitor and recent earthquakes: Eldvörp, name given to a row of cinder cones and spatter cones in staggered sections of 10 km, and surrounded by a lava field covering 20 km2. It dates back to a volcano-tectonic episode between 1210 and 1240, called "Reykjanes Fires".

 

Source: Icelandic Met office / IMO / Written by a specialist on May 16 02:23 GMT & video Rafn Sigurbjörnsson.

Stromboli - after the explosions - photo Peter Gabris 13.05.2022 - one click to enlarge
Stromboli - after the explosions - photo Peter Gabris 13.05.2022 - one click to enlarge

Stromboli - after the explosions - photo Peter Gabris 13.05.2022 - one click to enlarge

A look back at the Stromboli eruptions with photos by Peter Gabris:

On May 13, 2022, at 14:43:32 UTC (16:43:32 Locali), reports from the INGV OE and the Laboratory of Experimental Geophysics Laboratory / LGS - Department of Earth Sciences dell'Università di Firenze recorded a series of above-normal explosive events associated with a seismic signal in the VLP band with a maximum mass of 6.6x10-5 m (in space) and a ground deformation of about 1.88 microradiants (registered with tiltmetro OHO).

The explosions took place in a reporting phase of the very high CO2/SO2 ratio losing in the plume for some months, as reported in the weekly bulletins.

The series of explosive events generated an abundant fallout of material along the Sciara del Fuoco and also on the side of Stromboli, with hot material between 400 and 500 m altitude.

 

 

Sources: LGS, INGV OE, thanks to Peter Gabris for the photos

Stromboli - after the explosions, some vegetation fires - photo Peter Gabris 13.05.2022 - one click to enlarge
Stromboli - after the explosions, some vegetation fires - photo Peter Gabris 13.05.2022 - one click to enlarge

Stromboli - after the explosions, some vegetation fires - photo Peter Gabris 13.05.2022 - one click to enlarge

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
Etna SEC - the lava flow, seen from the "Mareneve" road near Fornazzo (eastern flank of Etna) on May 14, 2022 in the evening - photos Boris Behncke - one click to enlarge
Etna SEC - the lava flow, seen from the "Mareneve" road near Fornazzo (eastern flank of Etna) on May 14, 2022 in the evening - photos Boris Behncke - one click to enlarge

Etna SEC - the lava flow, seen from the "Mareneve" road near Fornazzo (eastern flank of Etna) on May 14, 2022 in the evening - photos Boris Behncke - one click to enlarge

The activity of the south-east crater of Etna has been mild for two days, during which the lava flows slowly from a fracture on its northern flank and feeds a flow, which stretches guaranteeing a splendid spectacle.

There are small puffs of ash, not likely to put a large area in crisis as a few months ago, and a few small dustings of incandescent pyroclastic materials, enough to ensure a beginning tourist season after the "Covid shutdown".

The tremor level remains high, in the red zone.

 

Sources: Boris Behncke & INGV OE

Etna - tremor at 15.05.2022 / 07h - Doc. INGV OE

Etna - tremor at 15.05.2022 / 07h - Doc. INGV OE

At Anak Krakatau, the main crater's observable plume is white with fine to medium intensity, rising about 25-100 meters from the summit.

The PVMBG informs a seismicity for this May 14 characterized by:

- 1 emission earthquake, with an amplitude of 8 mm and an earthquake duration of 12 seconds.
- 9 low frequency earthquakes, with an amplitude of 6 to 14 mm and an earthquake duration of 3 to 12 seconds.
- 4 episodes of continuous tremor, with an amplitude of 1-15 mm, dominating 3 mm.

Activity level remains at 3/siaga, with recommendation for people/visitors/tourists/climbers not to approach Mount Anak Krakatau or engage in activities within 5 km of the crater.

 

Sources: PVMBG, Magma Indonesia

Anak Krakatau - Sentinel-2 image from 05.12.2022 via Copernicus EU - click to enlarge

Anak Krakatau - Sentinel-2 image from 05.12.2022 via Copernicus EU - click to enlarge

Anak Krakatau - Sentinel-2 bands 12,11,4 image from 05.14.2022 - we can clearly see the new lava delta and the gas plume marking the bese of the cone - click to enlarge

Anak Krakatau - Sentinel-2 bands 12,11,4 image from 05.14.2022 - we can clearly see the new lava delta and the gas plume marking the bese of the cone - click to enlarge

Anak Krakatau - image Sentinel-2 bands 12,11,8A - thermal anomalies and degassing as of 05.14.2022 - via Mounts project - click to enlarge

Anak Krakatau - image Sentinel-2 bands 12,11,8A - thermal anomalies and degassing as of 05.14.2022 - via Mounts project - click to enlarge

New seismic swarm in the Reykjanes Peninsula: About 400 earthquakes have occurred in the peninsula since midnight May 14 and 900 earthquakes have occurred in the past 24 hours.
Five earthquakes of magnitude greater than 3 were measured yesterday in Reykjanestá. At 7:28 p.m., the magnitude 3.2 earthquake, at 5:04 p.m. from M 3.1, at 4:41 p.m. from M 3.3, at 3:41 p.m. from M 3.5 and at At 11:09 a.m. yesterday morning, an earthquake of magnitude 3.4 was measured in the same region.

A M4.7 earthquake in the Hengill geothermal area was very well felt in Reykjavik before 5 p.m. on May 14.

We're definitely watching for something that could be a precursor to an eruption", says Kristín Jónsdóttir, natural hazards group leader at the Icelandic Meteorological Office.

Reykjanes Peninsula - seismic swarm (with the Hengill area to the right) on 15.05.2022 / 05:40 - Doc. IMO
Reykjanes Peninsula - seismic swarm (with the Hengill area to the right) on 15.05.2022 / 05:40 - Doc. IMO
Reykjanes Peninsula - seismic swarm (with the Hengill area to the right) on 15.05.2022 / 05:40 - Doc. IMO

Reykjanes Peninsula - seismic swarm (with the Hengill area to the right) on 15.05.2022 / 05:40 - Doc. IMO

GPS stations near Þorbjörn have shown changes over the past two weeks that indicate a slight expansion at Svartsengi.
"These shifts that we see are around 10-15mm where they are greatest ", says Benedikt G. Ólafsson, a crustal movement specialist at the Icelandic Meteorological Bureau.

Such expansion may cause increased tension on the peninsula and promote increased seismic activity. Movements are also seen at remote GPS stations from Svartsengi following the current expansion.

Hellisheiði power plant which uses geothermal energy from the Hengill volcanic system - photo archive Icelandic volcanoes by Dave McGarvie 2005

Hellisheiði power plant which uses geothermal energy from the Hengill volcanic system - photo archive Icelandic volcanoes by Dave McGarvie 2005

Reykjanes main structures  - Volcanic systems of the Reykjanes Peninsula (in pink) and geothermal use areas (in yellow)  - map Saemundsson  / Iceland geosurvey research

Reykjanes main structures - Volcanic systems of the Reykjanes Peninsula (in pink) and geothermal use areas (in yellow) - map Saemundsson / Iceland geosurvey research

Hengill is a volcanic mountain range located in southwest Iceland, south of Þingvellir. The mountain range covers an area of about 100 km². The volcano is still active, as evidenced by its many hot springs and fumaroles, but the last eruption occurred around 2,000 years ago, before Iceland was settled.
The volcano is an important source of energy for the south of the country, which is captured at the Nesjavellir power station and the Hellisheiði power station.

Magma collection is believed to be ongoing beneath the peninsula and has been ongoing since the end of the eruption at Fagradalsfjall.

 

Sources: IMO & Óróapúls

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
Stromboli - major intensity explosion on 05.13.2022 / 2:43 p.m. - INGV webcam - one click to enlarge

Stromboli - major intensity explosion on 05.13.2022 / 2:43 p.m. - INGV webcam - one click to enlarge

Stromboli - Comparison between seismic amplitudes (UD) and inclination. The deformations of the ground indicate that the event (star) of May 13, 2022 enters the field of major explosions – Doc. LGS

Stromboli - Comparison between seismic amplitudes (UD) and inclination. The deformations of the ground indicate that the event (star) of May 13, 2022 enters the field of major explosions – Doc. LGS

Stromboli monitoring networks recorded a thermal anomaly from surveillance cameras at 4:43 p.m. (14:43 UTC). and a sequence of explosions of greater intensity than usual from different vents in the south-central area of ​​the crater terrace.

The activity produced a significant emission of coarse pyroclastic materials which abundantly covered the terrace of the crater and also reached the Pizzo; the ash cloud produced moved towards the southern quadrants.

At 6:35 p.m. (4:35 p.m. UTC), the parameters return to normal activity.

Stromboli - therm webcam sequence. 13.05.2022 - Doc. LGS - one click to enlarge

Stromboli - therm webcam sequence. 13.05.2022 - Doc. LGS - one click to enlarge

Stromboli - 13.05.2022 / 2:43 p.m. - Doc. Volcano Time Lapse

CCTV camera images showed that the previously communicated explosive sequence of higher intensity began from one of the vents in sector CS1 of the south-central crater area and was followed by at least five other explosions also from the CS1 sector, of less intensity due to the height and the dispersion of the coarse products. These covered the crater terrace, they also fell on Pizzo, and only to a lesser extent on the Sciara del Fuoco. The fine material produced during the sequence was dispersed in the SE direction.
From the seismic point of view, the explosive sequence, which was not anticipated by significant variations in the amplitude values ​​of the volcanic tremor and the amplitude and frequency of occurrence of VLP events, was visible at all stations. Stromboli seismic waves with a succession of numerous low-frequency seismic transients. The first event, of moderate amplitude, recorded at 2:42 p.m. UTC, was followed in the following three minutes by a dozen other events, including the most energetic at 2:43 p.m. UTC.

A series of infrasonic pressure waves were generated, with maximum values ​​of 500 Pa all located in the SW crater sector.
After the sequence of events, for about 10 minutes, the amplitude of the volcanic tremor remained higher than the values ​​recorded before the explosive activity. Currently, the average amplitude of the volcanic tremor, the amplitude and the rate of occurrence of VLP events have normal values.

Stromboli - fall of pyroclastic materials on the summit and the Sciara del Fuoco - LGS webcam 13.05.2022 / 2:45 p.m. - one click to enlarge

Stromboli - fall of pyroclastic materials on the summit and the Sciara del Fuoco - LGS webcam 13.05.2022 / 2:45 p.m. - one click to enlarge

Analysis of the clinometric signal from the Timpone del Fuoco station shows a transient of about 0.2 microradians during the explosive sequence, and is preceded by a gradual change in trend of the N-S component of about 0.2 microradians, which tends to enter the explosive phase later. The GNSS network did not register any significant changes during the explosive activity. However, it should be noted that from 11:30 UTC the stations of Punta Lena and Timpone del Fuoco recorded a shift towards S-SW of about 2 cm which returned around 13:30 UTC.
Once the phenomenon ended, the parameters returned to ordinary levels.

 

Sources: INGV OE / 3 communications of 13.05.2022, and LGS

On 2022-05-14, TROPOMI detected an enhanced SO2 signal of 3.77 DU at a distance of 23.4 km from Mutnovsky. Other close sources: Avachinsky & Karymsky. - Doc. Sentinel-5P Tropomi/DLR/BIRA/ESA

On 2022-05-14, TROPOMI detected an enhanced SO2 signal of 3.77 DU at a distance of 23.4 km from Mutnovsky. Other close sources: Avachinsky & Karymsky. - Doc. Sentinel-5P Tropomi/DLR/BIRA/ESA

A moderate eruptive activity of the Karymsky volcano continues. The explosions sent ash up to 5,500-5,700 m. amsl., the ash plume extends 28 km to the northeast of the volcano.

Sentinel-5P Tropomi detected a sulfur dioxide signal of 3.77 DU at a distance of 23.4 km from the Mutnovsky.

Explosive activity of the volcano continues. Ash explosions up to 12 km (39,400 ft) a.s.l. could occur at any time. Ongoing activity could affect international and low-flying aircraft.

The aviation code remains orange

 

Sources: KVERT & Tropomi

Katmai eruption of 1912- Doc. M. Mohner / Alaska state photo library

Katmai eruption of 1912- Doc. M. Mohner / Alaska state photo library

Strong northwesterly winds in the vicinity of Katmai and the Valley of Ten Thousand Smokes picked up loose volcanic ash that erupted during the Novarupta-Katmai eruption in 1912 and carried it southeast toward Kodiak Island on May 13, 2022. The National Weather Service has issued a SIGMET for this low level event and suggests the maximum cloud height is 6,000 feet above sea level.

This phenomenon is not the result of recent volcanic activity and occurs seasonally in the spring and fall during periods of high winds and dry snowless conditions in the Katmai region and other young areas. volcanics of Alaska. All volcanoes in the Katmai region (Snowy, Griggs, Katmai, Novarupta, Trident, Mageik, Martin) remain color coded GREEN.

Resuspended volcanic ash should be considered hazardous and could be harmful to aircraft and health.

 

Source: AVO / 13.05.2022 / 21:11 UTC

Piton de La Fournaise - Coulée 2007 in the Grand Brûlé 2007 - one click to enlarge

Piton de La Fournaise - Coulée 2007 in the Grand Brûlé 2007 - one click to enlarge

An interesting article has just appeared in Nature Communications:

"22 years of satellite imagery reveal an important destabilizing structure at Piton de la Fournaise",  by Quentin Dumont, Valérie Cayol, Jean-Luc Froger & Aline Peltier.

Here is the excerpt; for the complete text, see in Source.

" Volcanic activity can induce flank failure, sometimes generating large earthquakes and tsunamis. However, the failure structures have never been fully characterized and the failure mechanism is still debated. Magmatic activity is a possible trigger, either fault slip, which could be induced by dyke intrusions, or sill intrusions, which could experience contemporaneous normal displacements and slips.

Main intrusive structure and displacement mechanism of the eastern flank. - Doc. from 22 years of satellite imagery reveal a major destabilizing structure at Piton de la Fournaise. Common Nat 13, 2649 (2022). - details in source. - one click to enlarge

Main intrusive structure and displacement mechanism of the eastern flank. - Doc. from 22 years of satellite imagery reveal a major destabilizing structure at Piton de la Fournaise. Common Nat 13, 2649 (2022). - details in source. - one click to enlarge

At the level of the Piton de la Fournaise volcano, satellite imagery combined with inverse modeling highlights the trajectories of 57 magmatic intrusions that took place between 1998 and 2020. We show that a major arcuate dyke intrusion zone is connected at depth to a sill intrusion zone, which becomes a seaward fault zone, forming a spoon-shaped structure. Some sills are affected by contemporary normal displacement and seaward sliding.
Overall, the structure is characterized by a continuum of displacement ranging from no slip, to sheared supports, and finally to pure slip. Repeated intrusions into this spoon-shaped structure could trigger catastrophic collapses.

 

Source : Dumont, Q., Cayol, V., Froger, JL. et al. - 22 years of satellite imagery reveal a major destabilizing structure at Piton de la Fournaise. - Nature Communications 13, 2649 (2022). https://doi.org/10.1038/s41467-022-30109-w

This article is licensed under a Creative Commons Attribution 4.0 International License - http://creativecommons.org/licenses/by/4.0/.

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
Gunung Awu - PVMBG / Magma Indonesia Webcam 12.05.2022 / 12:54 WITA

Gunung Awu - PVMBG / Magma Indonesia Webcam 12.05.2022 / 12:54 WITA

The Geological Agency of the Ministry of Energy and Mineral Resources (ESDM) upgraded the activity status of Mount Awu in the Sangihe Islands, North Sulawesi, to Level III (Siaga or Eve) on Wednesday, May 11, 2022 , from Level II (Waspada or Caution) issued October 31, 2021. The public is urged to stay outside a 3.5 kilometer radius of the mountain peak

The last eruption that occurred in June 2004 was a magmatic eruption producing an eruption column as high as 3,000 meters from the summit.

"The eruption of Mount Awu can be explosive, magmatic, effusive or phreatic. The last eruption in June 2004 left a lava dome in its crater with a diameter of about 370 meters and a height of about 30 meters," said agency chief Eko Budi Lelono.

The massive Gunung Awu stratovolcano occupies the northern end of Great Sangihe Island, the largest in the Sangihe Arc. Deep valleys that form passages for lahars dissect the flanks of the volcano, which was built into a 4.5 km wide caldera. Powerful explosive eruptions in 1711, 1812, 1856, 1892, and 1966 produced devastating pyroclastic flows and lahars that caused over 8,000 cumulative deaths. Awu contained a summit crater lake which was 1 km wide and 172 m deep in 1922, but was largely ejected in the 1966 eruption.

 

Sources: ESDM, PVMBG, Magma Indonesia and Global Volcanism Program

Awu - the dome formed after 2004 - photo Aris Yanto 2015 - one click to enlarge

Awu - the dome formed after 2004 - photo Aris Yanto 2015 - one click to enlarge

Over the past 24 hours, Etna's southeast crater has returned to activity that has produced weak and sporadic Strombolian explosions accompanied by brief ash and steam emissions.

Etna - emission of ash and vapor on 12.05.2022 / 5:45 p.m. - webcam Emov0355 INGV OE

Etna - emission of ash and vapor on 12.05.2022 / 5:45 p.m. - webcam Emov0355 INGV OE

The National Institute of Geophysics and Volcanology, Etneo Observatory, announces that from approximately 7 p.m. local time, ash was observed from the Southeast crater associated with the opening of one or more vents on along the north side of the Southeast Crater, which produced a small lava flow whose front reached the north base of the crater. Thermal anomalies are low to moderate, between 2 and 12 MW on May 12 and 13.

The ash plume that has now formed reaches a height of about 3500 m a.s.l. The forecast model of the dispersion of the eruptive cloud indicates the SW direction.

Etna - The photos were taken by the staff of the INGV-Osservatorio Etneo on the evening of 12.05.2022 from Fornazzo (east side of Etna). - via INGV Vulcani - one click to enlarge
Etna - The photos were taken by the staff of the INGV-Osservatorio Etneo on the evening of 12.05.2022 from Fornazzo (east side of Etna). - via INGV Vulcani - one click to enlarge

Etna - The photos were taken by the staff of the INGV-Osservatorio Etneo on the evening of 12.05.2022 from Fornazzo (east side of Etna). - via INGV Vulcani - one click to enlarge

From the seismic point of view, the average amplitude of the volcanic tremor, which since about 22:00 UTC yesterday is characterized by large fluctuations around medium-high values, currently remains in the high range. The source of the tremor is located in correspondence with the Southeast crater at an altitude of about 3,000 m above sea level.
The rate of occurrence of infrasound events is low with sources located mainly in the Bocca Nuova crater area.
Analysis of the signals from the soil deformation monitoring networks does not reveal any significant anomalies.

 

Source: INGV OE, INGV Vulcani, Gio Giusa

Etna - tremor at 05.23.2022 / 05h - Doc. INGV OE

Etna - tremor at 05.23.2022 / 05h - Doc. INGV OE

Etna - seen at dawn on 13.05.2022 from Linguaglossa - photo Gio Giusa - one click to enlarge

Etna - seen at dawn on 13.05.2022 from Linguaglossa - photo Gio Giusa - one click to enlarge

The Mount Edgecumbe Volcanic Field (MEVF) is now classified as "historically active" by Alaska Volcano Observatory (AVO) standards because it is undergoing deformation related to the presence of magma penetrating three miles below. the surface.

Topographic map of southern Kruzof Island derived from Interferometric Synthetic Aperture Radar (IFSAR) data including hillshading and 10m contour lines. - with Crater ridge and Mt Edgecumbe - Doc. Matt Loewen via AVO

Topographic map of southern Kruzof Island derived from Interferometric Synthetic Aperture Radar (IFSAR) data including hillshading and 10m contour lines. - with Crater ridge and Mt Edgecumbe - Doc. Matt Loewen via AVO

Mount Edgecumbe, viewed from Sitka, Alaska. - Photo courtesy of Duncan Marriott / 26.12.2004 via AVO

Mount Edgecumbe, viewed from Sitka, Alaska. - Photo courtesy of Duncan Marriott / 26.12.2004 via AVO

"The Edgecumbe Volcanic Field in southern Kruzof Island lies on the North American Plate 10-15 km inside the Queen Charlotte-Fairweather Transform Fault. The Edgecumbe Volcanic Field is dominated by the symmetrical stratovolcano of Mount Edgecumbe and the adjacent Crater Ridge domes and crater.Mount Edgecumbe was named by Captain James Cook in 1778. The basal shield is approximately 35 cubic km and consists of basalt, basaltic andesite and andesite lava flows and breccias.The composite cone of Mount Edgecumbe is composed primarily of andesite and has a volume of about 3.5 km³.The low-silica rhyolite domes of Crater Ridge also contain about 3 .5 km³ of magma.

"The last significant eruptive activity was postglacial and produced voluminous pyroclastic deposits (dense rock equivalent of 7.6 km³). The major geomorphological features of the Edgecumbe volcanic field were formed during this activity and include cones of basaltic andesite scoria, an explosion crater in the Crater ridge domes during the eruption of rhyolitic pyroclastic flows and eruption of andesite and dacite tephra during the placement of the dome and the formation of craters on the cone of Mount Edgecumbe Tephra deposits produced by late Pleistocene and early Holocene activity of the Edgecumbe volcanic field have been found so far as far away as Juneau and Lituya Bay, 200 km to the north. Vents active during pyroclastic eruptions have a northeast-southwest alignment that likely marks a regional fissure (From Wood and Kienle (1990)).

 

Source: AVO

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Karymsky - explosive activity as of 04.05.2022 - photo S. Samoylenko via IVS FEB RAS - one click to enlarge

Karymsky - explosive activity as of 04.05.2022 - photo S. Samoylenko via IVS FEB RAS - one click to enlarge

A moderate eruptive activity continues at Karymsky.

A thermal anomaly over Karymsky was visible in satellite images from April 29 to May 6.

The May 4 explosions generated ash plumes that reached 3,200 m. above sea level. and drifted about 60 km to the SW.

 

This May 11, the explosions sent ashes up to 6,000 m. altitude, and a 7x10 km ash cloud moves 25 km west-northwest of the volcano.

Moderate activity of the volcano continues. Ash explosions up to 12 km a.s.l. could occur at any time. Ongoing activity could affect international and low-flying aircraft.

The aviation color code remains orange

 

Sources: KVERT & Global Volvanism Program

Semisopochnoi, Mt. Cerberus - photo USGS 10.05.2022 - one click to enlarge

Semisopochnoi, Mt. Cerberus - photo USGS 10.05.2022 - one click to enlarge

Low-level eruptive activity continues at Semisopochnoi on May 11, 2022.

Seismicity remains high with an intermittent tremor. Several explosions have been detected in seismic and infrasound data over the past day. Clear images from satellites and web cameras showed low level ash emissions.

Small eruptions producing minor ash deposits near the active north crater of Mount Cerberus and ash clouds generally below 3,000 m. above sea level have characterized recent activity. Small explosions and associated ash emissions may continue and be difficult to detect, particularly when heavy cloud cover obscures the volcano.
 

The Volcanic Alert Level is Watch, and the Aviation Code is Orange.
The Semisopochnoi is monitored by local seismic and infrasound sensors, satellite data, web cameras, and remote infrasound and lightning networks.

 

Source: AVO

Ili Lewotolok - eruptive activity on 11.05.2022 / 11:25 p.m. WITA - PVMBG / Magma Indonesia webcam - one click to enlarge

Ili Lewotolok - eruptive activity on 11.05.2022 / 11:25 p.m. WITA - PVMBG / Magma Indonesia webcam - one click to enlarge

At Lewotolok, the main crater plume is white and gray with fine, medium to thick intensity, about 100-500 meters from the summit. This May 11, 2022.

Seismicity is characterized by :

- 55 eruption earthquakes, with an amplitude of 12.4 to 38.1 mm and an earthquake duration of 25.8 to 67.8 seconds
- 73 emission earthquakes, with an amplitude of 1.9 to 25.4 mm and an earthquake duration of 22.4 to 255 seconds.
- 8 Harmonic episodes and 32 non-harmonic tremors
- 2 shallow volcanic earthquakes; 2 times with an amplitude of 5.6 to 38 mm and an earthquake duration of 25.6 to 26.5 seconds.
- 4 deep volcanic earthquakes
- 2 distant tectonic earthquakes
- 4 episodes of continuous tremor, with an amplitude of 0.2-1 mm, dominant 0.5 mm.

 

Activity level remains 3/Siaga-Veille, with recommendation to communities around Mount Ili Lewotolok as well as visitors/climbers/tourists not to conduct activities within 3km of Mount Ili summit/crater Lewotolok. The community of Jontona Village should always be aware of the potential threat of avalanches of weathered material which may be accompanied by hot clouds from the southeastern part of G. Ili Lewotolok peak/crater.

 

Source: PVMBG / Magma Indonesia

Etna SEC - burning ash emission at nightfall - photo © Salvatore Lo Giudice 11.05.2022 - one click to enlarge

Etna SEC - burning ash emission at nightfall - photo © Salvatore Lo Giudice 11.05.2022 - one click to enlarge

Etna - tremor at 12.05.2022 / 06h - Doc. INGV OE

Etna - tremor at 12.05.2022 / 06h - Doc. INGV OE

Small activity in the evening of May 11, 2022 at the southeast crater of Etna, with an emission of ash and gas, lying by the winds, and a visible incandescence following the explosive activity at nightfall.

Small rise in the tremor.

 

Sources: Salvatore Lo Giudice, EtnaNews, INGV OE

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Mt Ruapehu Crater Lake (Te Wai ā-moe) -photo 04.05.2022 / GeoNet - one click to enlarge

Mt Ruapehu Crater Lake (Te Wai ā-moe) -photo 04.05.2022 / GeoNet - one click to enlarge

High levels of volcanic gas emissions and strong volcanic shaking continue at Mount Ruapehu. The volcano is still at a high level of unrest. The Volcanic Alert Level remains at 2, with a greater chance of an eruption over the next four weeks than at Volcanic Alert Level 1.

Last week, steam plumes were observed above the crater lake of Mount Ruapehu (Te Wai ā-moe). Observation flights confirmed that these steam plumes were not caused by an eruption. Instead, they were linked to a combination of increased heat flux at the crater lake and still cold atmospheric conditions. Over the past 12 days, Crater Lake's temperature has peaked at 41°C after a four-week stint of 36-38°C. Our modeling suggests that maintaining lake temperature and the recent rise required approximately 300 to 400 MW of thermal energy.

Since the beginning of March, we have been recording a strong volcanic tremor at Mount Ruapehu. This is the most sustained and vigorous volcanic tremor recorded in two decades, and it has accompanied the increase in temperature of the crater lake. Although tremor levels remain elevated, there has been a decrease in tremor over the past week.

The high production of sulfur dioxide and carbon dioxide, and the strong sustained volcanic tremor continue to indicate that molten rock (magma) is driving this time of heightened unrest. Crater Lake's temperature increase reflects the increasing upwelling of hot fluids and gases through active vents. Available laboratory analyzes of the latest fluid and gas samples from Crater Lake show elevated temperatures within the hydrothermal system but no reaction with magmatic material.

 

Source: Geonet

Ruapehu - Hazards map and advice in the event of an eruption, updated on 10.05.2022 - Doc. GNS - one click to enlarge

Ruapehu - Hazards map and advice in the event of an eruption, updated on 10.05.2022 - Doc. GNS - one click to enlarge

Elevated surface temperatures and sulfur dioxide emissions have been detected at Cleveland in satellite data for the past two days, representing a departure from background activity.

AVO raises the Aviation Color Code and Volcano Alert Level to YELLOW/ADVISORY.

Cleveland Volcano forms the western portion of Chuginadak Island, a remote and uninhabited island in the east-central Aleutians. The volcano is located approximately 45 miles (75 km) west of the community of Nikolski and 940 miles (1,500 km) southwest of Anchorage.

Cleveland Volcano is monitored with a limited real-time seismic network. This smaller network inhibits AVO's ability to detect precursor disorders that can lead to an explosive eruption. Early detection of an ash-producing eruption may be possible using a combination of seismic, infrasound, lightning, and satellite data. Cleaveland eruptions typically generate small volcanic ash clouds that pose a hazard in the immediate vicinity of the volcano, although larger ash emissions are possible.

 

Source: AVO

Cleveland - photo Mees, Burke / 03.06.2020 via AVO - one click to enlarge

Cleveland - photo Mees, Burke / 03.06.2020 via AVO - one click to enlarge

Between May 2 and May 8, 2022, normal Strombolian-type explosive activity was observed at Stromboli. The total hourly frequency of explosions fluctuated between low values ​​(4 events/h) and medium values ​​(10 events/h). The intensity of the explosions was low and medium in the area of ​​the North crater and low in the area of ​​the Center-South crater.

As part of the activities of the DPC/INGV Annex A convention and the UNO departmental project, 2 inspections were carried out in the summit area on May 5 and 7 in order to make findings using drones from the area. of the crater and characterize its morpho-structural arrangement. Through data analysis, a DSM (Digital Surface Model) was obtained of the crater area with a resolution of 45 cm and two orthomosaics with a resolution of 11 cm and 53 cm. During the inspection on May 5, the activity was mainly characterized by light explosions of black ash.

Stromboli - 3D view derived from a Sentinel-2 image of April 12, 2022 - Doc. Copernicus EU

Stromboli - 3D view derived from a Sentinel-2 image of April 12, 2022 - Doc. Copernicus EU

Stromboli - A) shaded terrain model of the crater area; B) Orthomosaic; C) Thermal orthomosaic; D) explosion of May 5, 2022 in sector CS1; E) explosion of May 5, 2022 in sector N1 - doc. INGV OE

Stromboli - A) shaded terrain model of the crater area; B) Orthomosaic; C) Thermal orthomosaic; D) explosion of May 5, 2022 in sector CS1; E) explosion of May 5, 2022 in sector N1 - doc. INGV OE

One of the most beautiful places in Iceland is for sale.

The area, which covers 315 hectares, encompasses Fjaðrárgljúfur, one of the country's most important natural pearls.

Fjaðrárgljúfur Canyon was formed 9,000 years ago, at the end of the Ice Age. The retreat of a glacier upstream gave birth to a glacial lake, due to the presence of a rock lock composed mainly of palagonite, dated 2 million years. The water level rose to overcome this lock, and the Fjaðrá river began its work of erosion, forming a winding canyon about two kilometers long and deep in places a hundred meters in the rocks and the palagonite.

Fjaðrárgljúfur has been managed by the Icelandic Environment Agency for the past few years. The agency closed the area for weeks in recent years when tourist traffic caused damage to fragile vegetation around the canyon.

Fjaðrárgljúfur canyon - NB: respect the limits of the trail - photo archives © Bernard Duyck 2015 - one click to enlarge

Fjaðrárgljúfur canyon - NB: respect the limits of the trail - photo archives © Bernard Duyck 2015 - one click to enlarge

According to information from Frétablaðið, the purchaser of the land is an Icelander who works for tourism. The newspaper's sources estimate the purchase price to be between 300 and 350 million ISK.(2.2-2.5 million euros)

The Icelandic State can intervene and buy the land thanks to a right of first refusal, but they have a limited time.
 

Until now, there were no admission fees (parking and entry fee) for visitors to the canyon.

 

Sources: Frétablaðið & Iceland Review

Fjaðrárgljúfur canyon - photo archives © Bernard Duyck 2015 - one click to enlarge
Fjaðrárgljúfur canyon - photo archives © Bernard Duyck 2015 - one click to enlarge

Fjaðrárgljúfur canyon - photo archives © Bernard Duyck 2015 - one click to enlarge

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Santiaguito- abundant degassing on 09.05.2022 - photo Insivumeh

Santiaguito- abundant degassing on 09.05.2022 - photo Insivumeh

The Santiaguito Observatory reports abundant white outgassing at a height of 700 meters that propagates in a southwesterly direction, incandescence in the crater of the El Caliente dome and in front of the lava flow in a westerly direction and South West.

Weak and moderate boulder and ash avalanches continue to be recorded in the middle and front of the lava flow. Suspended ash is reported in the volcanic perimeter and at Finca El Faro and San José.

The volcano maintains high activity due to blocky lava extrusion into the Caliente dome in a west-southwest direction and unstable material within the crater, giving a likelihood of moderate to strong pyroclastic flows, with recommendation not to be in the barrancas of the volcano.

 

Source: Insivumeh

Sabancaya - activity from May 2 to 8, 2022 - Doc. I.G.Peru

Sabancaya - activity from May 2 to 8, 2022 - Doc. I.G.Peru

Last week, the eruptive activity of Sabancaya remained at moderate levels, with an average of 53 daily explosions, and plumes of gas and ash reaching up to 3,000 meters above the summit.

The IGP detected 324 earthquakes of volcanic origin associated with the internal circulation of magmatic fluids, and VT earthquakes, linked to the fragmentation of rocks.

The deformation, controlled by GNSS techniques, does not show any significant anomalies. Five thermal anomalies, with a maximum value of 58 MW, have been identified, associated with the presence of a lava body on the surface of the crater.

The volcanic alert is maintained in Naranja, with a non-accessible zone of 12 km radius around the crater.

 

Source: I.G.Peru

Etna - 09.05.2022 - an improved SO2 signal, 3.44 DU at a distance of 26.9 km from Etna - Doc. Tropomi/Sentinel5P/DLR/BIRA/ESA

Etna - 09.05.2022 - an improved SO2 signal, 3.44 DU at a distance of 26.9 km from Etna - Doc. Tropomi/Sentinel5P/DLR/BIRA/ESA

Etna - tremor at 10.05.2022 / 06h - Doc .INGV

Etna - tremor at 10.05.2022 / 06h - Doc .INGV

The tremor has increased slightly on Etna, and remains in the yellow/medium zone. There is also a slight increase in seismicity. There were several earthquakes that manifested to the northeast and southeast of the volcano. The strongest had a magnitude of 2.3.

Modis does not detect thermal anomalies.

Sentinel-5P/Tropomi detected detected an enhanced SO2 signal, 3.44 DU at a distance of 26.9 km from Etna.

LGS recorded a large number of infrasound events yesterday, indicating explosive outgassing. 1719 events were recorded at the MVT measuring station, for a maximum sound pressure of 0.79 Pa; 128 events were recorded at the ETN measuring station, for a maximum sound pressure of 0.43 Pa and were classified as weak. Most of the signals came from the direction of the central crater.

Etna - the summit craters - Photo Giò Giusa Aprile 2022 - one click to enlarge

Etna - the summit craters - Photo Giò Giusa Aprile 2022 - one click to enlarge

Access to the summit remains closed to individual travellers.
From the municipality of Nicolosi, the access ends at 2750 meters above sea level. The municipality of Belpasso authorizes an ascent up to an altitude of 2920 m. From April there is an exception for guided groups, who are allowed to ascend to the craters.

 

Source: INGV OE & LGS

Seamount Nootka - the 'Yellow Brick Road', a strange structure - doc. en.news.Yahoo

Seamount Nootka - the 'Yellow Brick Road', a strange structure - doc. en.news.Yahoo

A geological formation, within the Papahānaumokuākea Marine National Monument, a huge marine reserve that encompasses several islands in the northwest of the Hawaiian archipelago, was explored by the Ocean Exploration Trust expedition aboard the E/V Nautilus.

While diving on the top of seamount Nootka, the team discovered that the ocean floor here was oddly fragmented, in the form of perfectly rectangular bricks.

These are not the remains of an ancient civilization, but rather hyaloclastites produced when a lava flow comes into contact with water. This sudden cooling generates a thermal shock which will fracture the crystallizing rock.

The 90° fractures, visible on the screens, give the impression that they are bricks ... they are in fact the result of multiple eruptions, inducing several cycles of heating and cooling.

 

Source: Futuraplanet

the 'Yellow Brick Road' to Geologic Features of Liliʻuokalani Ridge Seamounts | Nautilus Live

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Whakaari / white island - geysering in waterlogged vent - survey flight May 2022 / GeoNet via Brad Scott - one click to enlarge

Whakaari / white island - geysering in waterlogged vent - survey flight May 2022 / GeoNet via Brad Scott - one click to enlarge

Monitoring data and observations from recent monitoring flights at Whakaari/White Island have confirmed that the level of volcanic unrest remains low.

The temperature of the gases and steam emitted continued to drop to a maximum of 111°C measured during the observation flight on April 27, 2022 (compared to 288°C on March 16, 2022).

Geyser activity was observed at one of the waterlogged vents during the same observation flight.

No minor or dilute volcanic ash emissions have been observed since late February 2022. Satellite ground deformation indicates minor uplift around the active zone of the vent lake, while seismic activity remains low.

Taken together, these observations remain consistent with low levels of volcanic unrest. The Volcanic Alert Level remains at Level 1 and the Aviation Color Code remains green.

 

Source : GeoNet / Brad Scott

Rincón de la Vieja - steam releases on 08.05.2022 / at 5:02 a.m. and 9:13 a.m. - Doc.. Ovsicori

Rincón de la Vieja - steam releases on 08.05.2022 / at 5:02 a.m. and 9:13 a.m. - Doc.. Ovsicori

At the Rincón de la Vieja volcano, no eruption is reported.
Seismic activity is similar, compared to yesterday.
At the time of this report, the winds are blowing to the northwest.
Several steam releases from the activity of the lake were observed, a.o. at 5:02 a.m. or 9:13 a.m. on May 08, 2022.

These exhalations are small and do not exceed the edge of the crater and therefore did not generate lahars. An almost continuous tremor with a frequency of 0.7-4 Hz and a moderate to strong amplitude is detected.

In recent days, geodetic observations show uplift and slight contraction of the summit.

 

Source : Ovsicori

Semeru - image archives 01.05.2022 - PVMBG / Magma Indonesia webcam

Semeru - image archives 01.05.2022 - PVMBG / Magma Indonesia webcam

Semeru - seismicity as of  08.05.2022 - Doc. Magma Indonesia

Semeru - seismicity as of 08.05.2022 - Doc. Magma Indonesia

Eruptive activity continues at Semeru, this May 8, 2022, with poor visibility, but seismic recordings on the rise:
- 111 eruption earthquakes, with an amplitude of 10-23 mm and an earthquake duration of 45-130 seconds.
- 4 avalanche earthquakes, with an amplitude of 2 to 5 mm and an earthquake duration of 40 to 50 seconds.
- 9 emission earthquakes, with an amplitude of 2 to 8 mm and the duration of the earthquake from 25 to 66 seconds.
- 5 distant tectonic earthquakes
- 2 Flood Vibration earthquakes, with an amplitude of 10-25 mm and an earthquake duration of 1260-2400 seconds.

The activity level remains at 3 / siaga, with recommendations of:
Do not carry out any activity in the southeastern sector along Besuk Kobokan, up to 13 km from the summit (the center of the eruption). Beyond this distance, the community does not conduct activities within 500 meters of the bank (river edge) along Besuk Kobokan due to the potential for expansion of hot clouds and lava flows. lava up to a distance of 17 km from the summit.

Do not travel within 5 km of the crater/summit of Mount Semeru as it is subject to fallout from incandescent projectiles.
Stay aware of the potential for hot cloud avalanches (APGs), lava avalanches and lahars along the rivers/valleys that originate at the summit of Mount Semeru, especially along Besuk Kobokan, Besuk Bang, Besuk Kembar and Besuk Sat as well as potential lahars in the rivers a small river which is a tributary of Besuk Kobokan.

 

Source: Magma Indonesia

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Kavachi - the eruption continues Sentinel-2 image as of 25.04.2022 and 05.05.2022 - Doc. Copernicus via "Un geólogo en apuros"  - one click to enlarge
Kavachi - the eruption continues Sentinel-2 image as of 25.04.2022 and 05.05.2022 - Doc. Copernicus via "Un geólogo en apuros"  - one click to enlarge

Kavachi - the eruption continues Sentinel-2 image as of 25.04.2022 and 05.05.2022 - Doc. Copernicus via "Un geólogo en apuros" - one click to enlarge

The latest Sentinel 2 / Copernicus satellite image dated May 5, 2022 which covers the area where the Kavachi volcano is located in the Solomon Islands, appears to show that the underwater eruption is still continuing judging by the clear tone of the waters and stain definition.

 

Source: Copernicus / Sentinel-2

Laguna del Maule - photo Álvaro Amigo / 19.06.2020 - one click to enlarge

Laguna del Maule - photo Álvaro Amigo / 19.06.2020 - one click to enlarge

The Sernageomin monitoring stations, located near the Laguna del Maule Volcanic Complex, recorded this Saturday 05/07 at 10:34 p.m., a seismic swarm of 650 volcano-tectonic events (VT) associated with rock fracturing.

The green alert is maintained.

 

Source: Sernageomin

Wolf - Location of thermic alerts updated on 5 April 2022 - Doc. IGEPN - one click to enlarge

Wolf - Location of thermic alerts updated on 5 April 2022 - Doc. IGEPN - one click to enlarge

The Wolf volcano (altitude: 1,710 m) located in the northern part of Isabela Island in the Galapagos archipelago, began a new eruptive period at 11:20 p.m. on January 6, 2022 Galapagos time (00:20 on January 7, 2022) .

The evolution of this eruption was monitored by seismic stations and different satellite systems, thanks to which it was possible to check mainly the emission and progression of the lava flows, as well as the emissions of volcanic gases.
The lava flows were emitted from an approximately 8 km radial fissure with at least 5 vents located on the southeast flank of the volcano. The lavas flowed reaching an approximate maximum distance of 18.5 km, without reaching the coastal margin and covered an approximate area of ​​more than 30 km2.

Wolf volcano - Preliminary map of lava flows emitted during the eruption of the Wolf volcano which began in January 2022 (Galapagos Islands). The map was made from PlanetScope satellite images / as of 04.22.2022 - IGEPN / F.J. Vasconez map - one click to enlarge

Wolf volcano - Preliminary map of lava flows emitted during the eruption of the Wolf volcano which began in January 2022 (Galapagos Islands). The map was made from PlanetScope satellite images / as of 04.22.2022 - IGEPN / F.J. Vasconez map - one click to enlarge

Wolf volcano - Sentinel 2 images, bands 8-4-3 / IR, showing the evolution of lava flows from Wolf volcano. - A) January 11, B) January 16 and C) May 1. - doc. IGEPN via Mounts project - one click to enlarge

Wolf volcano - Sentinel 2 images, bands 8-4-3 / IR, showing the evolution of lava flows from Wolf volcano. - A) January 11, B) January 16 and C) May 1. - doc. IGEPN via Mounts project - one click to enlarge

Thermal alerts have gradually decreased in recent days to the point of being almost absent, which is interpreted as a decrease in the rate of emission of lava flows, and a significant cooling of these. Likewise, the degassing of sulfur dioxide shows a downward trend, so that as of the date of this report, a month has passed without a report of SO2 emissions.

The monitoring parameters allowing the evolution of the eruption to be assessed are: seismic activity, degassing, deformation, thermal alerts, ash emissions. These parameters reached their maximum peak in early January 2022, after which they declined until returning to baseline (non-eruptive) values. Currently, thanks to satellite images, no advance of the lava fronts is observed, which seem to have stopped 150-200 meters from the coast and have gradually cooled.
Based on the technical criteria set out above, it is considered that this eruptive period is over.

 

Sources: IGEPN, Mounts project.

Reykjanes Peninsula - location and magnitude of earthquakes on 08.05.2022 - Doc. IMO
Reykjanes Peninsula - location and magnitude of earthquakes on 08.05.2022 - Doc. IMO
Reykjanes Peninsula - location and magnitude of earthquakes on 08.05.2022 - Doc. IMO

Reykjanes Peninsula - location and magnitude of earthquakes on 08.05.2022 - Doc. IMO

A magnitude 3.3 earthquake was felt in the Greater Reykjavík area at 10:46 a.m. on May 07, 2022.
A second of about M 3.5 followed.

The source of the earthquake was in the northern part of Kleifarvatn, where a fairly strong earthquake has been going on for a few hours.
This is the second time in a few days that earthquakes originating from Kleifarvatn have been discovered in the Greater Reykjavík area.

Fagradalsfjall eruption - Excessive carbon dioxide emissions can trigger eruptions. - photo mbl.is / Kristinn Magnússon - one click to enlarge

Fagradalsfjall eruption - Excessive carbon dioxide emissions can trigger eruptions. - photo mbl.is / Kristinn Magnússon - one click to enlarge

A scientific article published on May 2 in Nature Geoscience by Ólafur G. Flóvenz, geophysicist, in collaboration with experts from ÍSOR and GFZ, most likely attributes the landslides that occurred in Svartsengi in January, March and May 2020, to high pressure gases (carbon dioxide) that penetrated a conductive layer of water at a depth of about four kilometers below the geothermal system. This repeated under the Krýsuvík Central Geothermal System in August 2020. The gas pressure was sufficient each time to cause a landslide.

These events were a harbinger of the eruption that began at Fagradalsfjall on March 19, 2021. In addition to land rising and receding in high temperature areas, they also appeared in large seismic activity at Svartsengi and in changes in Earth's gravity with the landslide.

 

Þorvaldur Þórðarson, professor of volcanology at the University of Iceland, reacted to an article by Ólafur G. Flóvenz and others that was reported yesterday in Morgunblaðið. It was stated, among other things, that high-pressure magmatic gas probably caused terrestrial eruptions three times at Svartsengi and once at Krýsuvík 2020, and that this was a harbinger of the eruption at Geldingadalur.
Þorvaldur says that " the gas that caused the landslide in 2020 was released from the magma at a depth of 10-14 km, even deeper, which shows that the magma had already reached Fagradalsfjall. When the tremor started in 2021, the upper part of the earth's crust has opened up and magma has risen .When you look at how much outgassing was during the eruption, carbon dioxide has always been stable and has always come regardless the behavior of the eruption. However, the sulfur gases came out en masse. It is as if these two gases did not come from the same place. The sulfur gases accompanied the magma, but the carbon dioxide was like a bottom flow more regular."

The results of the study, which is the subject of the article, help people understand how magma starts from where it forms by partial melting of the mantle, settles at a certain depth and expands to until it finds its way to the surface. .
" If this is correct, then a gas pulse that causes surface deformation or an abnormally large emission of carbon dioxide can be a fairly strong predictor of an eruption ", says Þorvaldur.

 

Sources: IMO, Nature Geoscience, Morgunblaðið

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