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Earth of fire

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

sismologia

Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
Anak Krakatau - eruptive episode of 06.17.2022 / 00:43 WIB - PVMBG / Magma Indonesia webcam - one click to enlarge

Anak Krakatau - eruptive episode of 06.17.2022 / 00:43 WIB - PVMBG / Magma Indonesia webcam - one click to enlarge

The activity of Anak Krakatau continues on June 17, 2022.

Seismicity was characterized by:

- 3 eruption earthquakes, respectively at 00:42 WIB, with a plume of black ash observed at ± 500 m above the summit (± 657 m above sea level) recorded on a seismograph with a maximum amplitude of 62 mm and a duration of 53 seconds.
Another at 2:45 p.m. WIB, with the height of the ash column, gray to black, observed at ± 700 m above the summit (± 857 m above sea level). This eruption was recorded on a seismograph with a maximum amplitude of 58 mm and a duration of 71 seconds.
The third episode was observed at 6:39 p.m. WIB, with a black ash plume observed ±500 m above the summit (±657 m above sea level). This eruption was recorded on a seismograph with a maximum amplitude of 60 mm and a duration of 84 seconds.

- 7 emission earthquakes, with an amplitude of 14 to 34 mm and the duration of the earthquake from 10 to 27 seconds.
- 28 low frequency earthquakes, with an amplitude of 6 to 40 mm and an earthquake duration of 4 to 10 seconds.
- 2 hybrid/multiphase earthquakes
- 26 shallow volcanic earthquakes
- 5 deep volcanic earthquakes
- 4 episodes of continuous tremor, with an amplitude of 1 to 40 mm, dominating 3 mm.

 

The activity level remains at 3 / siaga; People/visitors/tourists/climbers should not approach Anak Krakatau or engage in any activities within 5km of the active crater.

 

Source: PVMBG, Magma Indonesia

Anak Krakatau - eruptive episode of 06.17.2022 / 2:45 p.m. WIB - PVMBG / Magma Indonesia webcam - one click to enlarge

Anak Krakatau - eruptive episode of 06.17.2022 / 2:45 p.m. WIB - PVMBG / Magma Indonesia webcam - one click to enlarge

Anak Krakatau - eruptive episode of 06.17.2022 / 6:07 p.m. - PVMBG / Magma Indonesia webcam - one click to enlarge

Anak Krakatau - eruptive episode of 06.17.2022 / 6:07 p.m. - PVMBG / Magma Indonesia webcam - one click to enlarge

This week from June 10 to 16, lava avalanches were observed 58 times southwestward at Merapi, dominating the Bebeng River with a maximum slip distance of 1,800 m.

In the southwest dome, there is no change in the height of the dome. For the middle dome, no significant morphological change was observed. According to photo analysis, the volume of the southwest lava dome is 1,551,000 m³ and the central dome is 2,582,000 m³.

The intensity of seismicity this week is still quite high. Mount Merapi's deformation, which was monitored using EDM this week, showed a distance shortening rate of 0.4 cm/day.

Merapi - visual and seismicity / deformation as of 06.16.2022 - Doc. BPPTKG

Merapi - visual and seismicity / deformation as of 06.16.2022 - Doc. BPPTKG

Merapi's volcanic activity is still quite high in the form of effusive eruption activity. The activity level remains at 3/siaga.The current potential danger is lava avalanches and hot clouds in the south-southwest sector covering Boyong River for up to 5 km, Bedog River, Krasak , Bebeng for a maximum of 7 km. The southeast sector covers the Woro River for a maximum of 3 km and the Gendol River for a maximum of 5 km. The ejection of volcanic material in the event of an explosive eruption can reach a radius of 3 km from the summit.

 

Sources: BPPTKG, PVMBG, Magma Indonesia

Kilauea - West Halemaʻumaʻu vent and lava lake, from northwest caldera rim looking south [V1cam] 2022-06-16 07:46 - HVO - click to enlarge

Kilauea - West Halemaʻumaʻu vent and lava lake, from northwest caldera rim looking south [V1cam] 2022-06-16 07:46 - HVO - click to enlarge

The eruption at Kīlauea Volcano's summit in Halema'uma'u Crater has continued for the past 24 hours. All recent lava activity has been confined to the crater, and current data indicates that this scenario is likely to continue.
Lava eruption from the West Halema'uma'u vent into the active lava lake and seeps on the crater floor have continued over the past 24 hours. The active lava lake showed continued surface activity with stable lava lake levels over the past 24 hours, remaining below overflow. Lava seepage activity continued along the northern and southern edges of the crater floor.

Kilauea -Halemaʻumaʻu - 06.17.2022 / 03:47 - HVO webcam - click to enlarge

Kilauea -Halemaʻumaʻu - 06.17.2022 / 03:47 - HVO webcam - click to enlarge

A deflationary event that began on June 14 caused the lava lake to fall 7 meters. Since this deflationary event, a 2.5 microradian inflationary event has occurred beginning at approximately 11:45 p.m. on June 15 and the lava lake has since risen 2 m. Lava seepage activity continued along the northern and southern edges of the crater floor.

Summit tiltmeters have recorded deflation over the past 24 hours. A sulfur dioxide emission rate of approximately 1,350 tonnes per day (t/d) was measured on June 10, 2022.

Current Volcanic Alert Level: Watch - Current Aviation Color Code: Orange

 

Source: HVO

Teide - the Pico Viejo from the summit - author not referenced - one click to enlarge

Teide - the Pico Viejo from the summit - author not referenced - one click to enlarge

This Friday, June 17, 2022, between 01:50 a.m. and 04:10 a.m. (Canarian time), the seismic network, operated by the Volcanological Institute of the Canary Islands (INVOLCAN), recorded a swarm of hybrid events of very low magnitude under the Teide volcano, with epicenters located southwest of PicoViejo. In this time interval of 2 hours and 20 minutes, at least 300 seismic events have been identified.


This seismic swarm has very similar characteristics to the swarms that were recorded on October 2, 2016 and June 14, 2019. The most likely origin of this type of swarm is the movement of fluids such as steam, gas or l water, inside the hydrothermal system of the Teide volcano. This swarm does not imply a higher probability of an eruption in the short/medium term, but it reminds us that Tenerife is still a volcanically active island.

 

Sources : IGN.es - InVolcan

Teide - Seismic swarm with epicentres located southwest of PicoViejo; and seismogram of 17.06.2022 / 02h – Doc. IGN.es
Teide - Seismic swarm with epicentres located southwest of PicoViejo; and seismogram of 17.06.2022 / 02h – Doc. IGN.es

Teide - Seismic swarm with epicentres located southwest of PicoViejo; and seismogram of 17.06.2022 / 02h – Doc. IGN.es

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
Etna - SEC lava flow on 18.05.2022 - Doc. Cam therm FLIR / INGV OE

Etna - SEC lava flow on 18.05.2022 - Doc. Cam therm FLIR / INGV OE

Etna - Situation of summit activity on 17.05.2022 - Doc. INGV Vulcani (Doc. above) -- Etna - image Sentinel-2 bands 12,11,8A on 19.05.2022 / 09:40 - Via Mounts project (image below) - click to enlarge
Etna - Situation of summit activity on 17.05.2022 - Doc. INGV Vulcani (Doc. above) -- Etna - image Sentinel-2 bands 12,11,8A on 19.05.2022 / 09:40 - Via Mounts project (image below) - click to enlarge

Etna - Situation of summit activity on 17.05.2022 - Doc. INGV Vulcani (Doc. above) -- Etna - image Sentinel-2 bands 12,11,8A on 19.05.2022 / 09:40 - Via Mounts project (image below) - click to enlarge

The National Institute of Geophysics and Volcanology announces that after the opening of an effusive vent on the northern flank of the Southeast Crater of Etna, communicated on 05/12/2022 at 8:38 p.m. local time, placed at a altitude of about 3250 m a.s.l.

The effusive activity stabilized in the following days, producing a lava flow which develops towards the ENE in the Valle del Leone desert whose most advanced front has currently reached an altitude between 2400 and 2300 m a.s.l. The new lava flow from the flank of the southeast crater of Etna flanks the one already in progress which formed around 3250 m.

At the same time, the SE crater is affected by a discontinuous Strombolian explosive activity of variable intensity which, in the most intense phases, produces a modest emission of ash which is rapidly diluted in the atmosphere.
From a seismic point of view, compared to the 12 cm press release, the trend of the gradual increase in the average amplitude of the tremor continues in the range of high values.

The sources of the tremor are located in the Southeast crater around 3000 m. above sea level.

 

Source: INGV – extraordinary press release 18.05.2022 & INGV Vulcani

Etna - tremor, variations on 20.05.2022 / 05h - Doc. INGV

Etna - tremor, variations on 20.05.2022 / 05h - Doc. INGV

The Svartsengi seismic swarm on the Reykjanes peninsula is still ongoing.

Yesterday (May 19), around 370 earthquakes were detected in the region, the largest a M3.0 at 11.35am. The greatest seismic activity is now north of Grindavík.
Land inflation around Svartsengi and Þorbjörn has reached 4 centimeters in recent weeks, as evidenced by a latest interferogram.
Landslides can occur on the slopes and sides of mountains when earthquakes of these magnitudes occur. Caution is advised for people in these areas.

 

Source: Orapuls

Grindavik / Svartsengi - deformation - interferogram between 9 and 19.05.2022 - Doc. IMO

Grindavik / Svartsengi - deformation - interferogram between 9 and 19.05.2022 - Doc. IMO

Large volcanic eruptions are often preceded by detectable manifestations, such as seismicity, gas emissions, or variations in the level of ambient volcanic activity. The detection of these changes is therefore valuable for anticipating the hazard and the volcanic risk. Nevertheless, these manifestations are difficult or even impossible to measure for volcanoes that are difficult to access.

This is the case of Nyiragongo, in the Democratic Republic of Congo, whose eruptions have devastated the city and the region of Goma on several occasions in the past, until recently in May 2021.

Barrière et al. [2022] use satellite imagery, mainly radar, to continuously measure the oscillations of the lava lake that fills the summit crater of Nyiragongo, and the rates of lava effusion over time. These rates and the lake level are found to be correlated with seismic activity, demonstrating that they are the manifestation of changes in the dynamics and pressurization of the magmatic system at depth. This work thus demonstrates the importance of satellite data for detecting and anticipating volcanic eruptions at Nyiragongo and other volcanoes in the world.

 

Sources: Barrière, J., Nicolas d'Oreye, , Smets, B., Oth, A., Delhaye, L., Subira, J., et al. (2022). Intra-crater eruption dynamics at Nyiragongo (D.R. Congo), 2002–2021. Journal of Geophysical Research: Solid Earth, 127, e2021JB023858. https://doi.org/10.1029/2021JB023858

—Michael Poland, Associate Editor, Journal of Geophysical Research: Solid Earth; translation by Isabelle Manighetti, Editor in Chief, JGR: Solid Earth

Nyiragongo lake level over time. (a) View of the Nyiragongo volcano and its summit crater where the lava lake extends (photos taken by the Volcanological Observatory of Goma, in November 2013 on the left and in April 2014 on the right). (b) Variation in the altitude of the lava lake (in meters above sea level) over time, measured occasionally in the field between 1948 and 2020, and continuously by radar satellite since 2006 (red line) . Lake and crater level changes are linked to eruptive activity, with major subsidence during the 1977, 2002, and 2021 eruptions. The 2021 eruption, however, was preceded by a rise in the lake level, suggesting a pressurization of the magmatic system at depth. Credit: Barrière et al. [2022]

Nyiragongo lake level over time. (a) View of the Nyiragongo volcano and its summit crater where the lava lake extends (photos taken by the Volcanological Observatory of Goma, in November 2013 on the left and in April 2014 on the right). (b) Variation in the altitude of the lava lake (in meters above sea level) over time, measured occasionally in the field between 1948 and 2020, and continuously by radar satellite since 2006 (red line) . Lake and crater level changes are linked to eruptive activity, with major subsidence during the 1977, 2002, and 2021 eruptions. The 2021 eruption, however, was preceded by a rise in the lake level, suggesting a pressurization of the magmatic system at depth. Credit: Barrière et al. [2022]

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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, #Sismologia, #Tectonics

May is "Volcano Awareness Month" in Washington State, where 5 active volcanoes dominate the skyline. The peaks are often snow-capped and appear serene, but recent eruptions, steaming vents and occasional earthquakes remind us of their volcanic origins and potential for future eruptions.

"Volcano Awareness Month" in Washington state, where 5 active volcanoes dominate the skyline. - Doctor. USGS - one click to enlarge

"Volcano Awareness Month" in Washington state, where 5 active volcanoes dominate the skyline. - Doctor. USGS - one click to enlarge

Today, stratovolcanoes dominate the horizon (triangles) but they are only the most recent example of volcanism. Scientists used maps and a DEMS to find 2,999 vent locations in the US portion of the Cascades (pink areas). There are probably more vents that have been buried or eroded.

Tectonic context of the Cascades - Doc. USGS - one click to enlarge

Tectonic context of the Cascades - Doc. USGS - one click to enlarge

The tectonics of the northeast Pacific give a varied volcanic history. The Pacific Northwest has an active volcanic arc (Cascades Range), a nearby oceanic ridge (Pacific Plate-Juan de Fuca Plate Spreading Ridge), the world's youngest floodplain basalt province (Columbia River Basalt), a range hotspots of young volcanoes to the east (Yellowstone Trend), volcanism linked to continental extension, etc.

It is a volcanological paradise. The western margin of North America has long been dominated by dextral subduction and transtension. This animation attempts to simplify a complex tectonic interaction through cross-sections.

Volcanic evolution of the northwest of the North American continent: 55 million years of history. - IRIS earthquake sciences/animation accompanying a talk during IAVCEI 2017 in Portland, OR. Written and directed by Anita Grunder, Oregon State University Graphics, animation and narration by Jenda Johnson, Earth Sciences Animated - Reviewed by Ray Wells, U.S. Geological Survey

Halema'uma'u's summit crater also underwent major changes, and its lava lake disappeared during the 2018 eruption of Kïlauea. While lava flows in lower Puna drained the summit magma reservoir, Halemaʻumaʻu suffered 62 collapses (some with explosive eruptions). Each gradual collapse was marked by earthquakes that were felt throughout the summit. When the dust settled (and there was a lot of dust), the collapses had lowered the crater floor by more than 500 m.

The end of the 2018 eruption and caldera collapse events resulted in a period of quiescence not seen in Kīlauea for over 35 years. It also brought a new and interesting change to the volcano.

For the first time since written records began, a lake of water formed in the deep pit of Halemaʻumaʻu. First noticed in July 2019, water continued to slowly fill the crater over the next year and a half until it was about 50m deep.

On the night of December 20, 2020, the lake of water evaporated within an hour or two when Halema'uma'u erupted again. Within a day, the new lava lake was deeper than the water lake, and it continued to grow and fill the crater until May 2021. Again, Kīlauea did not stay silent for a long time. Halemaʻumaʻu began a new eruption in September 2021; an eruption that continues to this day. These two eruptions filled Halemaʻumaʻu with over 320 m of lava.

Volcano Awareness Month in Washington State, Kilauea Evolution and New Earthquake Swarm in Reykjanes.

Kilauea - A) Top left, photo of Halema'uma'u before the start of the 2018 collapse events with the decade-old active lava lake that formed in 2008. B) Top right , pictured after the 2018 collapse events caused the floor of Halema'uma'u crater to drop more than 1,600 feet (500 m) in just 4 months. C) Bottom left, in July 2019, a lake of water began to form in the newly deepened Halemaʻumaʻu, and this lake continued to grow over the next year and a half. D) Bottom right, the December 2020 eruption boiled the lake water overnight and continued through May 2021 before another eruption began in September 2021, continuing until 'now. All photos courtesy of the U.S. Geological Survey's Hawaiian Volcano Observatory. - one click to enlarge

Summary of activity as of 05.05.2022 : The eruption at the summit of Kīlauea Volcano in Halema'uma'u Crater has continued for the past 24 hours. All recent lava activity has been confined to the crater, and current data indicates that this scenario is likely to continue.

Eruption of lava from the western Halema'uma'u vent into the active lava lake and crater floor has continued over the past 24 hours. The active lava lake has experienced continuous surface activity and its surface level has been relatively stable during this period. Relatively slow lava seeps continued along the northeastern and southern margins of the crater floor yesterday, and this morning a particularly vigorous and expansive seep began along the northwestern margin just after 2 a.m. morning. Flyby measurements on April 6, 2022 indicated that the crater floor had experienced a total elevation of approximately 99 meters and 66 million cubic meters of lava had been shed since this eruption began on September 29, 2021.

Current volcanic alert level: Watch
Current Aviation Color Code: Orange.
No significant changes were noted at the summit or in the East Rift Zone.

 

Sources: HVO-USGS Daily update & Volcano Watch / Kïlauea's dynamic landscape: reflections on the past four years.

Kïlauea / Halema'uma'u - HVO therm webcam 05.05.2022 / 7:44 PM HST

Kïlauea / Halema'uma'u - HVO therm webcam 05.05.2022 / 7:44 PM HST

IMO has detected 173 tremors in the past 48 hours in the Reykjanes Peninsula. Most of the tremors occurred northeast of the Krýsuvík volcanic system, specifically beneath Kleifarvatn. In addition to the current M 3.4 earthquake, there was an M 2.9 earthquake before. Both tremors were felt in the greater Reykjavik area Lake Kleifarvatn is associated with a fault system and has been the site of several earthquakes over the past week.

More than 1,000 earthquakes have been detected under Reykjanes in the past 3 weeks. Most occur in the regions of Thorbjörn, Eldvörp and Kleifarvatn.

 

Source: IMO

Reykjanes Peninsula - Seismic swarm as of 05.05.2022 / 5:15 p.m. - Doc. IMO
Reykjanes Peninsula - Seismic swarm as of 05.05.2022 / 5:15 p.m. - Doc. IMO
Reykjanes Peninsula - Seismic swarm as of 05.05.2022 / 5:15 p.m. - Doc. IMO

Reykjanes Peninsula - Seismic swarm as of 05.05.2022 / 5:15 p.m. - Doc. IMO

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
Sinabung - 13.04.2022 / 11:42 WIB - PVMBG / Magma Indonesia webcam - one click to enlarge

Sinabung - 13.04.2022 / 11:42 WIB - PVMBG / Magma Indonesia webcam - one click to enlarge

Sinabung activity continues, still at level 3 / siaga.
A plume of gas, sometimes embellished with ash, overcomes the volcano from 50 to 400 meters.
The seismicity of the week of April 6 to 12 is characterized by:
- 4 collapse earthquakes
- 32 blast/emission earthquakes
- 30 hybrid earthquakes
- 2 volcanic earthquakes
- 7 local & 38 distant tectonic earthquakes
- 4 earthquakes linked to lahars.

Sinabung - seismicity of the last 4 months - Doc. PVMBG / Magma Indonesia - one click to enlarge

Sinabung - seismicity of the last 4 months - Doc. PVMBG / Magma Indonesia - one click to enlarge

Communities and visitors/tourists should not carry out activities in the villages that have been relocated, as well as within a radial radius of 3 km from the summit of Mount Sinabung, as well as a sectoral radius of 5 km for the south- east sector, and 4 km for the east-north and west sector.
In the event of ash rain, people are advised to wear masks when leaving the house to reduce the health impact of volcanic ash. Securing drinking water installations and cleaning the roofs of houses from heavy volcanic ash so that they do not collapse.
People who live and live near the rivers that originate at Mount Sinabung should remain alert to the dangers of lahars.

 

Sources: PVMBG, Magma Indonesia

Semeru - 13.04.2022 / 06:07 WIB - PVMBG / Magma Indonesia webcam

Semeru - 13.04.2022 / 06:07 WIB - PVMBG / Magma Indonesia webcam

In Semeru, for the week of April 6 to 12, the PVMBG reports:
- 605 eruption earthquakes
- 2 collapse earthquakes
- 29 emission and blast earthquakes
- 3 harmonic episodes
- 2 volcanic earthquakes
- 21 lesser tectonic earthquakes
- 3 earthquakes linked to lahars

Semeru - weekly activity summary from April 6 to 12, 2022 - Doc. PVMBG

Semeru - weekly activity summary from April 6 to 12, 2022 - Doc. PVMBG

Eruptive activity continues with a level 3 / siaga. It is advised not to 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.
Not to move within a radius of 5 km from the crater/summit of Mount Semeru, as the area is likely to undergo incandescent projections.
And to remain 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: PVMBG, Magma Indonesia

Reykjanes Peninsula - location and magnitudes of earthquakes on 13.04.2022 / 06:20 - Doc. IMO
Reykjanes Peninsula - location and magnitudes of earthquakes on 13.04.2022 / 06:20 - Doc. IMO
Reykjanes Peninsula - location and magnitudes of earthquakes on 13.04.2022 / 06:20 - Doc. IMO

Reykjanes Peninsula - location and magnitudes of earthquakes on 13.04.2022 / 06:20 - Doc. IMO

A seismic swarm began on April 12 at around 9:20 p.m. in the Reykjanes Peninsula, with a magnitude 3.9 earthquake, followed by several smaller earthquakes, measuring near magnitude 3. Earthquake activity has been almost continuous since the large quake. earthen.
ENSu has heard that the largest earthquake was observed in Reykjavík, so it can be assumed that it was well felt in many parts of the Reykjanes peninsula.
The crisis follows the pattern of activity that has characterized the peninsula over the past two years, as activity jumped between areas.

 

Source: IMO

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
Sangay Volcano - Aerial photograph archives by Patricio Ramon.

Sangay Volcano - Aerial photograph archives by Patricio Ramon.

The surface and internal activity of Sangay, in Ecuador, remains qualified as high by the IGEPN.

For the day from April 2 to 3 / 11 a.m., seismicity is characterized by 39 explosion earthquakes, 110 LP earthquakes and 10 tremor episodes.

Through photos of ECU-911, an emission of gas and ash was observed more than 1000 meters above the level of the crater to the west.

The Washington VAAC reported ash emissions at 870 and 1170 meters above the summit in a west, southwest direction.
The MOUNTS system recorded 399.6 tons of SO2 on 2022-04-02 at 1:30 p.m. TL.
FIRMS records 38 thermal alerts and MIROVA records 1 high thermal alert (VRP 266 MW) during the period considered ... during the afternoon, it rose to VRP 821 MW, and this April 4 to VRP 1242 MW


Alert level - SNGRE: Yellow

 

Source : IGEPN

Sangay - thermal anomalies and radiative power on 04.04.20220 / 03:55 - Doc. Mirova - one click to enlargeSangay - thermal anomalies and radiative power as of 04.04.20220 / 03:55 - Doc. Mirova - one click to enlargeSangay - thermal anomalies and radiative power on 04.04.20220 / 03:55 - Doc. Mirova - one click to enlargeSangay - thermal anomalies and radiative power as of 04.04.20220 / 03:55 - Doc. Mirova - one click to enlarge

Sangay - thermal anomalies and radiative power on 04.04.20220 / 03:55 - Doc. Mirova - one click to enlargeSangay - thermal anomalies and radiative power as of 04.04.20220 / 03:55 - Doc. Mirova - one click to enlarge

Observations and monitoring data over the past two months at Whakaari/White Island gradually trend back to lower levels of unrest typical of the volcano's long-term behavior. The decision to lower the Volcanic Alert Level to Level 1 is not based on changes in a single data set, but on the GNS Science Volcano Monitoring Group's collective interpretation of all monitoring data and their trends over the past two months. Datasets considered include observations from observation flights, web cameras, gas data, vent temperatures, ground deformation, and seismic activity.

Whakaari / White Island - alert level 1 - photo GNS

Whakaari / White Island - alert level 1 - photo GNS

The temperature of the emitted gases and steam remains high, but has dropped to less than 300°C. Sulfur dioxide (SO2), hydrogen sulfide (H2S) and carbon dioxide (CO2) gas release rates are at or below long-term trends, as are ground deformation and l seismic activity. No minor or dilute ash emissions have been observed since late February 2022.

Taken together, these observations and the downward trends in the major data sets over the past two months are consistent with low levels of unrest. As such, the Volcanic Alert Level is lowered to Level 1 and the Aviation Color Code is changed to Green.

The Volcanic Alert Level reflects the current level of volcanic unrest or activity and is not a prediction of future activity. Volcanic Alert Level 1 indicates that the main hazards are those expected during volcanic unrest; steam discharge, volcanic gases, earthquakes, landslides and hydrothermal activity. Although Volcanic Alert Level 1 is primarily associated with environmental hazards, an eruption hazard also exists and eruptions can still occur with little or no warning.

 

Source: GeoNet

Anak Krakatau - morphological changes between February 2 and April 2, 2022 - Copernicus Sentinel-2 images - one click to enlarge

Anak Krakatau - morphological changes between February 2 and April 2, 2022 - Copernicus Sentinel-2 images - one click to enlarge

An eruption took place on March 24 and 25 on the Anak Krakatau volcano, forming a small volcanic cone in the crater area. The new shape of the crater is visible when comparing images from February 3 (before) and April 2 (after the eruption).

The activity level remains at 2 / waspada, with recommendations not to approach the 2 km zone around the crater.

 

Source: Sentinel-2 Copernicus and PVMBG

Erta Ale - images Sentinel-2 bands 12,11,8A from 03.04.2022 / 07:36 - Doc. via Mounts project one click to enlarge
Erta Ale - images Sentinel-2 bands 12,11,8A from 03.04.2022 / 07:36 - Doc. via Mounts project one click to enlarge

Erta Ale - images Sentinel-2 bands 12,11,8A from 03.04.2022 / 07:36 - Doc. via Mounts project one click to enlarge

Weak to moderate thermal anomalies are reported from the last week of March through April 3 at Erta Ale, with a larger spot at the southern pit crater.

This activity was corroborated by a few rare observers on site

 

Sources: Mirova, Mounts project and Copernicus Sentinel-2

Reykjanes Peninsula - seismic swarm on 03.04.2022 / 4.15 p.m. & 04.04.2022 / 06.55 a.m. - Doc. IMO
Reykjanes Peninsula - seismic swarm on 03.04.2022 / 4.15 p.m. & 04.04.2022 / 06.55 a.m. - Doc. IMO
Reykjanes Peninsula - seismic swarm on 03.04.2022 / 4.15 p.m. & 04.04.2022 / 06.55 a.m. - Doc. IMO
Reykjanes Peninsula - seismic swarm on 03.04.2022 / 4.15 p.m. & 04.04.2022 / 06.55 a.m. - Doc. IMO

Reykjanes Peninsula - seismic swarm on 03.04.2022 / 4.15 p.m. & 04.04.2022 / 06.55 a.m. - Doc. IMO

Around 2:00 p.m. UTC on April 3, 2022, an earthquake swarm started north of the city of Grindavík / Reykjanes Peninsula. There are similarities to a tension-breaking swarm of earthquakes, suggesting that inflation is again occurring in the Fagradalsfjall volcano. The strongest earthquake had a magnitude of Mw3.3 and the second largest earthquake had a magnitude of Mw3.0.

The swarm appears to be short-lived and in sharp decline.

 

Source: IMO (no comments from IMO)

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Anak Krakatau - eruptive episode of 30.03.2022 / 1:27 p.m. loc. - webcam Sertung / PVMBG - Magma Indonesia - one click to enlarge

Anak Krakatau - eruptive episode of 30.03.2022 / 1:27 p.m. loc. - webcam Sertung / PVMBG - Magma Indonesia - one click to enlarge

Eruptive activity has continued for a few days at Anak Krakatau.

It is characterized on March 29 by:

- 3 eruption earthquakes, with an amplitude of 44-55 mm and an earthquake duration of 35-74 seconds.
- 38 emission/blast earthquakes, with an amplitude of 14 to 50 mm and an earthquake duration of 12 to 65 seconds.
- 19 harmonic episodes
- 30 low frequency earthquakes
- 14 shallow volcanic earthquakes
- 8 deep volcanic earthquakes
- and continuous tremor with an amplitude of 1 to 45 mm, dominating 7 mm.

 

An eruptive episode occurred this Wednesday, March 30, 2022 at 1:26 p.m. WIB, with a gray ash plume observed ± 700 m above the peak. This eruption was recorded on a seismograph with a maximum amplitude of 60 mm and a duration of 96 seconds.

 

Sources: PVMBG, Magma Indonesia

Sabancaya - activity report from 21 to 28.03.2022 - Doc. IGPeru

Sabancaya - activity report from 21 to 28.03.2022 - Doc. IGPeru

Between March 21 and 27, 2022, the eruptive activity of Sabancaya remained at moderate levels, with a daily average of 29 explosions, accompanied by plumes of gas and ash reaching 2,200 meters above the summit.

The I.G.P. mentions for this period a relatively low seismicity, with 163 earthquakes of volcanic origin, associated with the circulation of internal magmatic fluids, and no VT type earthquakes.

No significant deformation anomalies; seven thermal anomalies, of max. 30 MW, associated with the presence of a superficial lava body in the crater.

The volcanic alert remains at naranja, with a non-accessible zone of 12 km radius around the crater.

 

Source: I.G.Peru

Etna - degassing at Bocca Nuova and the southeast crater on 03.22.2022 / 06:33 a.m. - EMOV / INGV OE webcam

Etna - degassing at Bocca Nuova and the southeast crater on 03.22.2022 / 06:33 a.m. - EMOV / INGV OE webcam

Etna - degassing at summit craters  - Doc. INGV OE

Etna - degassing at summit craters - Doc. INGV OE

The INGV reports a variable rate degassing activity at the summit craters of Etna between March 21 and 27, 2022, as well as weak seismic fracturing activity. The amplitude of tremor, with sources located under the central craters, remains low.
Weak infrasonic activity is reported near inconspicuous Bocca Nuova.
Ground deformation monitoring networks have not recorded any significant changes over the past week.
At gas level: the lux of SO2 is at a low level.
The soil CO2 flux shows increasing average values.
The partial pressure of dissolved CO2 in the aquifer shows values ​​in seasonal variability.
Helium isotope ratio shows high values ​​(03/23/2022).
Thermal activity in the summit area was at a low level after the February 21, 2022 lava fountain.

 

Source: INGV OE

São Jorge - Earthquake ML 3.8 at the SSW of Velas on 03.29.2022 / 9:56 p.m. - Doc. IVAR

São Jorge - Earthquake ML 3.8 at the SSW of Velas on 03.29.2022 / 9:56 p.m. - Doc. IVAR

In the Azores, uncertainties remain as to the fate of possible volcanic activity on São Jorge.

Since March 19, more than 20,000 earthquakes have been recorded to date, of which 208 earthquakes have been identified as "felt" by the population. The most energetic was of local magnitude 3.8 on the Richter scale on 03.29.2022 at 9:56 p.m.

The activity is located in the central part of São Jorge (54 km long by 8 km max. wide), precisely along a WNW-ESE trending fault, in a sector between Las Velas and Faja do Ouvidor.

GNSS deformation data points to a magmatic dyke intrusion in the epicentral area.

No anomalies of the geochemical parameters.

 

There is a possibility of a volcanic eruption, although not imminent, and the alert level is set at V4.

 

Sources: CIVISA & IVAR

São Jorge - seismicity on 03.28.2022 - more than 20,000 earthquakes since 03.19 - Doc. CIVISA

São Jorge - seismicity on 03.28.2022 - more than 20,000 earthquakes since 03.19 - Doc. CIVISA

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After the phreatomagmatic eruption of the main crater from 07:22 to 08:59 yesterday March 26, 2022), two phreatomagmatic events occurred at 04:34 and 05:04 today March 27, recorded by the Taal Volcano Network (TVN) based on seismic records and visual cameras. These events produced plumes 800 meters and 400 meters high, respectively, from the main crater that drifted southwest.

Taal - phreatomagmatic episode of 26.03.2022 - video screenshot Phivolcs

Taal - phreatomagmatic episode of 26.03.2022 - video screenshot Phivolcs

In the past 24 hours, the TVN recorded 14 volcanic earthquakes, including 10 volcanic tremor events lasting 2 to 3 minutes and 4 low frequency volcanic earthquakes. Activity at the main crater was dominated by upwelling of hot volcanic fluids in its lake which generated 1,000 meter high plumes that drifted southwest. Sulfur dioxide emissions averaged 6,957 tonnes/day on March 25, 2022.

Maximum temperatures of 63.7°C were last measured from Main Crater Lake on February 25, 2022. Based on ground deformation parameters from electronic tilting, continuous GPS and InSAR monitoring, the he volcanic island of Taal and the Taal region began to deflate in October 2021.

Taal - summary of observations of the last 24 hours on 27.03.2022 / 05h - Doc. Phivolcs - one click to enlarge

Taal - summary of observations of the last 24 hours on 27.03.2022 / 05h - Doc. Phivolcs - one click to enlarge

Taal - average SO2 emissions in 2020 & 2022 - Doc. Phivolcs - one click to enlarge

Taal - average SO2 emissions in 2020 & 2022 - Doc. Phivolcs - one click to enlarge

Alert Level 3 (magmatic unrest) prevails over Taal Volcano. This means that there is magmatic intrusion at the main crater which could still lead to further eruptions. DOST-PHIVOLCS strongly recommends the evacuation of Taal Volcano Island and the high risk barangays of Bilibinwang and Banyaga, Agoncillo and Boso-boso, Gulod and East Bugaan East, Laurel, Batangas Province due to the risks possible pyroclastic density currents and volcanic tsunami. eruptions then occur.

 

Source: Phivolcs

Mount Pelée - photo archives ©-OVSM-montagne-pelée via Outremers 360

Mount Pelée - photo archives ©-OVSM-montagne-pelée via Outremers 360

Between March 18 and 25 / 4 p.m. UTC, the volcanological and seismological observatory of Martinique recorded 2 low-energy volcano-tectonic earthquakes under Mount Pelée, associated with the micro-fracturing of the volcanic edifice; the hypocentres are located between 700 meters and 1,100 meters deep.

An extension of two zones of deteriorated vegetation, located between Morne Plumé and Rivière Chaude, was observed and verified by a helicopter flight and satellite images.

The alert level remains yellow / vigilance

 

Source: OVSM

São Jorge - alignment of cones on the fissural system of Manadas - via GEVolcan

São Jorge - alignment of cones on the fissural system of Manadas - via GEVolcan

The earthquakes continue in São Jorge, and remain localized between 7 and 15 km deep (IPMA). All earthquakes recorded so far are of low magnitude and show a tectonic origin.

Within the framework of geodetic monitoring, CIVISA, in collaboration with other entities, is strengthening the observation network based on GNSS stations and the processing of satellite images. The existing data to date corroborate the seismological observations by indicating the existence of some deformations in the epicentral zone.

The integration of the available information allows us to conclude that the tectonic structures where the historical eruptions of 1580 and 1808 took place, and the seismovolcanic crisis of 1964, in the Fissural Volcanic System of Manadas, have been reactivated, and it is possible to admit the occurrence of a deep magmatic intrusion.

CIVISA warns of the possibility of earthquakes that can reach magnitudes greater than those recorded so far, as well as the danger of landslides potentiated by seismic activity and adverse weather conditions that affect the archipelago.

There is a real possibility that a volcanic eruption will occur, but there is no evidence that it is imminent.

As a result, CIVISA has been on ALERT V4 since 3:30 p.m. on March 20.

Many inhabitants of Velas, a city close to the epicenters, have settled with relatives in the east of the island; others have left São Jorge according to the government, which advises against any unnecessary travel. (RTL info)

 

Sources: CIVISA, IPMA

São Jorge - voluntary departures of part of the inhabitants - photo via-RTL-Info 26.03.2022

São Jorge - voluntary departures of part of the inhabitants - photo via-RTL-Info 26.03.2022

São Jorge - sismicité au 27.03.2022  -  Doc. CIVISA

São Jorge - sismicité au 27.03.2022 - Doc. CIVISA

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