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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

Effusive and explosive activity continues in La Palma / Cumbre Vieja, at high levels. During the night and this morning, frequent lava rises occurred at the level of the crater.
Large amounts of lava can be seen flowing in waves from the pierced crater, covering the lower northwest flanks of the cone with leaf-shaped flows.
These lava floods are likely caused by partial collapses at or around the lower vent in particular.

According to Pevolca & InVolcan, a new eruptive vent has opened southeast of the main vent. It ejects gases and pyroclasts.

La Palma / Cumbre Vieja - gas and pyroclast emissions from the new vent - photo CSIC 15.10.2021

La Palma / Cumbre Vieja - gas and pyroclast emissions from the new vent - photo CSIC 15.10.2021

The two streams that are south of La Laguna mountain are monitored, as they could converge and reach the sea.

The last Copernicus map dated October 14 at 19:02 UTC mentions 733 ha covered by lava flows, and 1,817 buildings destroyed.

La Palma - Cumbre Vieja - images Sentinel-2 bands 12.11.4 (top) and bands 12.11.8A (bottom) from 15.10.2021- one click to enlarge
La Palma - Cumbre Vieja - images Sentinel-2 bands 12.11.4 (top) and bands 12.11.8A (bottom) from 15.10.2021- one click to enlarge

La Palma - Cumbre Vieja - images Sentinel-2 bands 12.11.4 (top) and bands 12.11.8A (bottom) from 15.10.2021- one click to enlarge

La Palma Cumbre Viela - the lava flows at 14.10.2021 / 19:02 UTC - Doc.Copernicue EMSR

La Palma Cumbre Viela - the lava flows at 14.10.2021 / 19:02 UTC - Doc.Copernicue EMSR

The CSIC posted a video in which Vincente Soler, titular volcanologist, exhibits a sample taken by a colleague in an area near the eruptive center which, in the absence of laboratory verification, is inclined to classify as pre-oceanic sediment. island (more than 2 million years old), with strong similarities with the "restingolitas" emitted during the eruption of the submarine Tagoro volcano, in El Hierro.

 

Sources: IGNes, CSIC, InVolcan, Pevolca, IGM, Copernicus.

La Palma Cumbre Vieja - 14.10.2021- sample similar to "restingolitas" presented by Vicente Soler, volcanologist at CSIC. - Image CSIC

La Palma Cumbre Vieja - 14.10.2021- sample similar to "restingolitas" presented by Vicente Soler, volcanologist at CSIC. - Image CSIC

Lava effusion continued this week at the Great Sitkin in the Aleutian Arc, and lava now fills more than half of the summit crater. Satellite imagery from October 11 showed that two lava lobes, flowing over low points on the crater rim, extend down a slope 330 m to the south and 350 m to the west. Lava also reached the rim of the crater on its northern periphery. In a few areas, lava advanced over snow and ice, but no abnormal melting, vapor formation or water accumulation was observed. This indicates that melt rates are likely low and that there is no indication of impending hydrological hazards.

The lava lobes which have passed the edge of the summit crater flow into small valleys developed on the volcanic edifice. The terrain is steep in these areas, and boulders of lava and lava rubble could break away from the terminus of the flow lobes without warning and form small rock avalanches in these valleys. Such avalanches can release ash and gas and could travel several hundred meters beyond lava flows; they would be dangerous for anyone in these areas.

Satellite imagery shows a likely-formed boulder deposit extending 450 m beyond the western flow lobe terminus.

The level of seismicity has been slightly elevated over the past week and there have been persistent small earthquakes likely associated with the ongoing lava flow. No explosive activity or ash emission was detected in seismic, infrasound, satellite or web camera data.

There is no indication of how long the lava flow lasted during the current eruption, and it is possible that explosive activity could occur with little or no warning.

Current volcano alert level: Watch
Current Aviation Color Code: Orange.

 

Source: AVO

Great Sitkin - WorldView-3 SWIR image from 02.10.2021 / 22:56 UTC - Doc.AVO MM.Loewen (The red-orange areas are high temperature lava, while the blue is snow. The light blue is the vegetation and browns to blacks are the rock.) - one click to enlarge

Great Sitkin - WorldView-3 SWIR image from 02.10.2021 / 22:56 UTC - Doc.AVO MM.Loewen (The red-orange areas are high temperature lava, while the blue is snow. The light blue is the vegetation and browns to blacks are the rock.) - one click to enlarge

In Merapi, on Java, during the week of October 8 to 14, 2021, the BPPTKG reports avalanches of incandescent blocks were observed 41 times towards the southwest with a maximum sliding distance of 2,000 m.

The height of the southwest lava dome has decreased by ± 2 m, and the height of the central lava dome has been increased by approximately ± 4 m. The volume of the southwest lava dome is 1,609,000 m³ and the central dome is 2,927,000 m³.

This week's seismicity is higher than that of last week. The Merapi deformation which was monitored using EDM and GPS this week showed no significant changes.

Merapi - activity from 09.10.2021 / 05.37 loc. - Doc. PVMBG Magma Indonesia

Merapi - activity from 09.10.2021 / 05.37 loc. - Doc. PVMBG Magma Indonesia

Merapi - morphological changes of the past week - Doc. BPPTKG 10/14/2021

Merapi - morphological changes of the past week - Doc. BPPTKG 10/14/2021

Merapi - seismicity between 8 and 14.10.2021 - Doc. BPPTKG

Merapi - seismicity between 8 and 14.10.2021 - Doc. BPPTKG

The activity level remains at 3 / siaga.

The current potential danger consists of lava avalanches and hot clouds in the southeast-southwest sector for a maximum of 3 km to the Woro River, and 5 km to the Gendol, Kuning, Boyong rivers. , Bedog, Krasak, Bebeng and Putih. During this time, 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 and Magma Indonesia.

Bali - Tectonic earthquake of M 4.8 and localization near the Agung - Doc. BMKG - one click to enlarge
Bali - Tectonic earthquake of M 4.8 and localization near the Agung - Doc. BMKG - one click to enlarge

Bali - Tectonic earthquake of M 4.8 and localization near the Agung - Doc. BMKG - one click to enlarge

An earthquake of M4.8 was recorded between Agung and Batur, on Bali, this 16.10.2021 at 03:18 WIB; destruction is reported in Rendang / Karangasem.

Three aftershocks followed.

To be monitored carefully: landslides are likely to occur and new cracks may open following these earthquakes.

 

Source: BMKG

Bali / NW of Agung - Damage after the M4.8 earthquake on October 16, 2021 - BMKG photos

Bali / NW of Agung - Damage after the M4.8 earthquake on October 16, 2021 - BMKG photos

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
La Palma / Cumbre Vieja - 3 active craters as of 05.10.2021 / 11:43 p.m. - Doc. TVC

La Palma / Cumbre Vieja - 3 active craters as of 05.10.2021 / 11:43 p.m. - Doc. TVC

Eruptive activity continues at Cumbre Vieja on La Palma: During the night of October 5 to 6, powerful fountains are observed at three craters.

The height of the eruptive column measured at 7:30 UTC on October 5 is 4,000 m, showing a slight descent of the eruptive cloud.

Sulfur dioxide emissions mainly concern West Africa and the Atlantic, where they would extend to the Caribbean.

La Palma - strong SO2 signal at a distance of 15.0 km at CumbreVieja with 56.21DU of SO2 -. Weight estimated at less than 300 km 41.5 kt. - image Sentinel-5P / Tropomi 05.10.2021 - Doc. DLR / BIRA / ESA

La Palma - strong SO2 signal at a distance of 15.0 km at CumbreVieja with 56.21DU of SO2 -. Weight estimated at less than 300 km 41.5 kt. - image Sentinel-5P / Tropomi 05.10.2021 - Doc. DLR / BIRA / ESA

Since 24 hours, 75 earthquakes have been located in the southern part of the island of La Palma, near the current volcanic eruption.
An increase is observed both in the number of earthquakes and in their magnitudes compared to previous days, 7 of the recorded earthquakes have a magnitude greater than or equal to 3.5 (mbLg).

As in previous days, most of the seismicity is located 10-15 km deep, in the area where the swarm started on September 11, although 7 of them are located deeper, between 25 and 40 km.

The average amplitude of the volcanic tremor shows a slight gradual increase since yesterday morning and continues in the same average range of values ​​compared to that observed in this eruption. No significant pulse has been recorded in the past 24 hours.

La Palma / Cumbre Vieja - seismicity at 05.10.2021 / 12:45 - Doc. IGNes

La Palma / Cumbre Vieja - seismicity at 05.10.2021 / 12:45 - Doc. IGNes

The island's network of permanent GNSS stations shows slight deflation in the vertical component of stations near eruptive centers. These results are consistent with those obtained by InSAR, in which we can see an area that presents a pattern compatible with a possible subsidence between the Sentinel1 images of September 28 and October 4.
 

Pevolca and DSN report that the affected area exceeds 420.12 hectares on October 5 at 3 p.m., 6.74 hectares more than the day before. The lava flows remain in their bed, with a maximum width of 1,250 m. The ashes impacted an area of ​​1,750 ha. The lava delta covers 36 ha.

 

Sources: IGNes, Pevolca, RTVC, Copernicus, European Commission, DSN

La Palma / Cumbre vieja - - earthquakes, lava flows, extension of ashes at 05.10.2021 / 07h - Doc. CIEM - one click to enlarge

La Palma / Cumbre vieja - - earthquakes, lava flows, extension of ashes at 05.10.2021 / 07h - Doc. CIEM - one click to enlarge

From July 2021, INGV's monitoring systems have highlighted the variation of certain geophysical and geochemical signals at Vulcano, in particular those linked to the activity of the hydrothermal system which supplies the fumaroles of the Fossa crater and the degassing zone. from the Grotte dei Palizzi, located at the southern base of the cone.

In more detail, an increase in the temperature of these fumaroles and a variation in the composition of the gases were observed, with a greater contribution from the components directly linked to the magmatic degassing (CO2 and SO2).

The temperature of the fumarole gases increased to maximum values ​​of 340 ° C. Diffuse outgassing along the southern edge of the crater has also increased.

Vulcano - fumaroles bordering the crater - photo archives © Bernard Duyck

Vulcano - fumaroles bordering the crater - photo archives © Bernard Duyck

From a seismic point of view, from September 13 a significant increase in microseismicity was observed in the area of ​​the La Fossa crater. This low-energy seismicity, generally localized in the first kilometer of depth under the cone, is linked both to duct resonance phenomena and to fracturing processes in a hydrothermal environment, where weathered rocks have poor mechanical properties.
The current phase of increase was also characterized by the presence of seismic events (called VLP, Very Long Period events) with a lower frequency than that of microseisms. These seismic signals have never been recorded for 15 years; their presence is compatible with an increase in fluids which induces pressurization of the ducts and consequent resonance phenomena. As for the seismicity of fracturing (earthquakes) linked to the dynamics of the tectonic structures present in the Vulcain region, it did not show significant variations and remains at a very low level.

With regard to soil deformations, from mid-August GPS measurements showed a modest expansion of the area of ​​the Fossa cone. This process accelerated in mid-September, and is still ongoing, with maximum displacements of up to 1 cm (northward, on the north side of the cone).

 

Source: INGVvulcani blog

Morphotectonic map of Vulcano - Doc. INGV & image Sentinel-2 / 03.10.2021 - one click to enlargeMorphotectonic map of Vulcano - Doc. INGV & image Sentinel-2 / 03.10.2021 - one click to enlarge

Morphotectonic map of Vulcano - Doc. INGV & image Sentinel-2 / 03.10.2021 - one click to enlarge

Vulcano La Fossa - 06.10.2021 / 07:27 - webcam INGV

Vulcano La Fossa - 06.10.2021 / 07:27 - webcam INGV

In Nyiragongo / DRC, Mirova records moderate thermal anomalies, between VRP 13 and 78 Mw, for the period from October 3 to 6 ... activity returns to the crater.

 

Source: Mirova

Nyiragongo - Sentinel-2 bands 12,11,8A & Modis thermal volcanic activity at 04.10.2021 - Doc. Mirova _Last

Nyiragongo - Sentinel-2 bands 12,11,8A & Modis thermal volcanic activity at 04.10.2021 - Doc. Mirova _Last

A seismic swarm started on 09/27/2021 and is still in progress just south of Keilir, in the Reykjanes Peninsula, at the northern end of the dyke that intruded in February-March this year.

About 7000 earthquakes have been detected, 16 with M3-M4.2, about 2.5 / day since 9/29.

 

Source : IMO / Kristín Jónsdóttir

Keilr - IMO update on 05.10.2021 - Via Kristín Jónsdóttir

Keilr - IMO update on 05.10.2021 - Via Kristín Jónsdóttir

Reykjanes Peninsula - location and magnitude of earthquakes southwest of Keilir - Doc. IMO
Reykjanes Peninsula - location and magnitude of earthquakes southwest of Keilir - Doc. IMO
Reykjanes Peninsula - location and magnitude of earthquakes southwest of Keilir - Doc. IMO

Reykjanes Peninsula - location and magnitude of earthquakes southwest of Keilir - Doc. IMO

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

Since the last press release and until 24 hours yesterday, September 26, there was little seismicity in the eruptive zone of Cumbre Vieja, with a single earthquake located at 21:03 UTC of magnitude 2.5 (mbLg). Throughout this morning, between 4:00 a.m. and 7:00 a.m. UTC, a seismic swarm occurred in the area with 16 earthquakes located between 7 and 14 km deep.
The largest earthquake occurred at 06:05 UTC with 3.2 (mbLg).

The average amplitude of the volcanic tremor remained around the average values ​​of yesterday's eruption and began to increase sharply from 9 p.m. It reached a maximum value at 00:00 today and from that time until 9:00 a.m. it dropped sharply, coinciding with the observations of a decrease in surface flow on September 27.

La Palma - pulses of ashes and tremor - 27.09.2021 in the morning - InVolcan

La Palma - pulses of ashes and tremor - 27.09.2021 in the morning - InVolcan

The lava is no longer visible and sporadic ash emissions continue. They fall on La Palma, but also on the other Canary Islands.

"What happened today is ultimately only the result of the lack of gas in the magmatic system" according to David Calvo, spokesperson for InVolcan

This new calmer phase is normal, but we must keep an eye on the evolution of the eruption: at the seismic level, long-period hybrid events or LP mixed with rupture earthquakes or "tornillos" are observed, first-order eruptive precursors, indicating a short-term eruption.

La Palma / Cumbre Vieja éruption - de grands quantités de cendres sont tombées et menacent l'intégrité des habitations - photo auteur inconnu

La Palma / Cumbre Vieja éruption - de grands quantités de cendres sont tombées et menacent l'intégrité des habitations - photo auteur inconnu

La Palma / Cumbre Vieja - sismo. showing tornillo-type earthquakes - Doc. IGN 09/27/2021 / 3:16 p.m.

La Palma / Cumbre Vieja - sismo. showing tornillo-type earthquakes - Doc. IGN 09/27/2021 / 3:16 p.m.

La Palma / Cumbre Vieja -sismogram and spectrogram from 09/27/2021/16 at 6 p.m. loc. - Doc. IGNes - one click to enlarge

La Palma / Cumbre Vieja -sismogram and spectrogram from 09/27/2021/16 at 6 p.m. loc. - Doc. IGNes - one click to enlarge

La Palma / Cumbre Vieja - trémor at 09/28/2021 / 6:36 a.m. - Doc. IGNes

La Palma / Cumbre Vieja - trémor at 09/28/2021 / 6:36 a.m. - Doc. IGNes

Around 6:45 p.m., RTVC announced the reactivation of the activity, with weak Strombolian explosions.

After a period of calm, an effusive phase has arrived where lava flows, of a more fluid nature, descend from the main cone.

The volcano formed several mouths which specialized in different things:

- the lowest at the base of the pyroclastic cone are those which expel the most lava, very hot fluids very liquid> 1200ºC and with little gas, Hawaiiana type.

- the middle of the strombolian type pyroclastic cone with much more gas and which forms the ash and lapilli explosions, as well as the pyroclastic cone and finally

- behind the main cone and in the higher areas, there are more explosions of very violent phreatomagmatic type, which project many gases and water vapor at high speed, forming a lot of very fine ash ... (Volcanes y Ciencia Hoy)

La Palma / Cumbre Vieja - resumption of Strombolian activity in the evening of 27.09.2021 - Doc. RTVC

La Palma / Cumbre Vieja - resumption of Strombolian activity in the evening of 27.09.2021 - Doc. RTVC

La Palma / Cumbre Vieja - 09.27.2021 / 8 p.m. / webcam therm. InVolcan and lava flows at 9:40 p.m. / InVolcan - one click to enlargeLa Palma / Cumbre Vieja - 09.27.2021 / 8 p.m. / webcam therm. InVolcan and lava flows at 9:40 p.m. / InVolcan - one click to enlarge

La Palma / Cumbre Vieja - 09.27.2021 / 8 p.m. / webcam therm. InVolcan and lava flows at 9:40 p.m. / InVolcan - one click to enlarge

7 additional hectares have been covered since the last data. The south flow maintains a low flow rate. The northern flow, more active, is between 800 and 1,000 meters from the coast of Tazacorte

First estimate of the quantity emitted by the eruption of La Palma: 46.3 million m³ of material expelled on September 27, 2021 (press release from IGNes)

 

Sources : IGNes, RTVC, Copernicus, Volcanes y Ciencia Hoy

Suwanosejima - 09/27/2021 / 9:06 p.m. - JMA webcam

Suwanosejima - 09/27/2021 / 9:06 p.m. - JMA webcam

An eruption occurred at Suwanosejima (Mitake crater) at 1:51 p.m. on the 26th, accompanied by a plume that rose 2200m above the crater rim.
The volcanic ash moves southwest of the crater, and within an hour, is reported in large quantities of ash in the village of Toshima

In the area going from the crater about 4 km to the southwest, there is a risk of fallout from small volcanic bombs.

On September 27 at 9 p.m., the JMA announced the incandescence accompanying an eruption 700 meters above Mitake crater.

 

Source: JMA

Crete island - M6 earthquakes of 09/27/2021 / 6:17 GMT - EMSC location map

Crete island - M6 earthquakes of 09/27/2021 / 6:17 GMT - EMSC location map

An earthquake, of magnitude 5.8 according to the Geodynamic Observatory of Athens, M6 according to the American Institute USGS, occurred at 06:17 GMT on 27.09.2021 about twenty kilometers from Heraklion, capital of the island of Crete. It was followed by many aftershocks of strong magnitude (M4.5 - 4.3) It particularly affected the agricultural town of Arkalohori, where a worker died and where extensive damage was observed, according to Spiros Georgiou, head of the Civil Protection press office. Nine people were slightly injured.


The epicenter of the earthquake, with a depth of 10 km, was recorded 346 km south of the Greek capital, according to the Athens Observatory.
Stephen Hicks pointed out that this is an outage that has yet to be mapped, but is similar to the two neighboring sowers. It is the strongest earthquake since 1959 in Crete.

 

 

Sources: EMSC, RTBf

Crete island - - M6 / 27.09.2021 earthquake and localization in relation to faults - Doc. GFZ - Geofon / Caputo & al - one click to enlarge

Crete island - - M6 / 27.09.2021 earthquake and localization in relation to faults - Doc. GFZ - Geofon / Caputo & al - one click to enlarge

Crete island - 09.27.2021 - extensive material damage in this area to old buildings - photo via EMSC

Crete island - 09.27.2021 - extensive material damage in this area to old buildings - photo via EMSC

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
Karymsky - photo D. Melnikov / IVS FEB RAS, KVERT 09/17/2021

Karymsky - photo D. Melnikov / IVS FEB RAS, KVERT 09/17/2021

A moderate eruptive activity continues at Karymsky, with an ash plume on September 17 at 2,000-2,500 meters asl. extending eastward for 38 km.

On September 18, explosions were accompanied by an ash plume at more than 4,300 m. asl., moving 145 km east and northeast of the volcano.

A thermal anomaly marks the volcano.

The aviation code remains orange, other ash explosions can occur at any time, reaching an altitude of 6-7 km and affecting air traffic.

 

Sources: KVERT & Mirova / Sentinel-2

Karymsky - image Sentinel-2 bands 12,11,8A and Modos thermal volcanic activity from 09.19.2021 / 00h41 - Doc. Mirova S2MIR_Last

Karymsky - image Sentinel-2 bands 12,11,8A and Modos thermal volcanic activity from 09.19.2021 / 00h41 - Doc. Mirova S2MIR_Last

In Fagradalsfjall, around 2:45 p.m. on September 18, police and civil defense announce the closure of Trail A. Lava has now started to flow over the reserve areas near Trail A and it won't be long before it begins to flow on the path and up to Nátthagakriki.

Police and rescue teams are now working to clear the trail. People are ordered to go to trail B or C. Trail C is particularly recommended in this regard. Caution is recommended: the course of events remains unpredictable and lava can flow with great speed.

 

Around 5:40 p.m. local time, the tremor began to drop suddenly ... yet another behavior of this surprising volcano. Due to the weather on webcams, it's hard to tell how long the lava is flowing or if lava is still in the crater.

 

Sources: Police and Civil Defense of Suðurnes, Hraun.vedur, RUV, mbls

Fagradalsfjall - fall of the tremor on 19.09.2021 - Doc. Hraun.vedur.is

Fagradalsfjall - fall of the tremor on 19.09.2021 - Doc. Hraun.vedur.is

The seismic activity in Cumbre Vieja / La Palma, which started on the 11 at 03:18 (UTC), has decreased over the past 48 hours, however, over the past 12 hours there has been a slight increase with an earthquake of magnitude 3.2 mbLg located at 03:26 (UTC) today, at a depth of 0.1 km, which was felt by the population of intensity III (EMS98). So far and since the start of the series, 5391 earthquakes have been detected, of which 1102 have been located.

The maximum cumulative vertical deformation is of the order of 10 cm in the zone close to seismicity and its distribution is still compatible with a center of pressure in this zone. These movements were observed both with the island's GNSS network and with InSAR data (Sentinel-1).

Source: IGN 18.09.201

La Palma - seismic swarms at 18.09.2021 / 12h - IGNes

La Palma - seismic swarms at 18.09.2021 / 12h - IGNes

La Palma - nbr. earthquakes per hour between 10.09 and 18.09 - Doc. InVolcano

La Palma - nbr. earthquakes per hour between 10.09 and 18.09 - Doc. InVolcano

La Palma - interferometric analyzes by Sentinel-1 / variations between 2 satellite passes - one click to enlargeLa Palma - interferometric analyzes by Sentinel-1 / variations between 2 satellite passes - one click to enlarge

La Palma - interferometric analyzes by Sentinel-1 / variations between 2 satellite passes - one click to enlarge

La Palma remains under close monitoring :

INVOLCAN today installed a seismic network on La Palma. It will allow a type of signal: the volcanic tremor, to be detected with more sensitivity, if it occurs.
A seismic network is a set of seismic stations installed at a short distance from each other which, in addition to detecting seismic waves, makes it possible to establish the direction from which these waves originate.
Using analysis techniques similar to those used by telecommunication antennas, this tool will detect with even more sensitivity any seismic signal coming from inside the volcano, including volcanic tremor, which is an important precursor of a possible eruptive phase.
This activity was made possible thanks to the VOLRISKMAC (MAC / 3.5b / 124) and VOLRISKMAC II (MAC2 / 3.5b / 328) projects, co-financed by the INTERREG VA Spain-Portugal MAC Cooperation Program (Madeira-Azores-Canaries) 2014- 2020 from the European Commission.

Update from 4.30 p.m. (Canary Island time): no significant thermal anomaly was observed in the surface environment of the western slope of Cumbre Vieja and in the summit area, during helicopter overflight

Source :  InVolcan

La Palma - 09.18.2021 - Installation of the seismic network, IR thermography by helicopter, sampling in Dos Aguas (Barranco de las Angustias) by the teams InVolcan - one click to enlarge
La Palma - 09.18.2021 - Installation of the seismic network, IR thermography by helicopter, sampling in Dos Aguas (Barranco de las Angustias) by the teams InVolcan - one click to enlargeLa Palma - 09.18.2021 - Installation of the seismic network, IR thermography by helicopter, sampling in Dos Aguas (Barranco de las Angustias) by the teams InVolcan - one click to enlarge

La Palma - 09.18.2021 - Installation of the seismic network, IR thermography by helicopter, sampling in Dos Aguas (Barranco de las Angustias) by the teams InVolcan - one click to enlarge

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
  Klyuchevskoy - the lava from the flank eruption on the snow this 13.03.2021 - Sentinel-2 image via Coperncus - one click to enlarge

 Klyuchevskoy - the lava from the flank eruption on the snow this 13.03.2021 - Sentinel-2 image via Coperncus - one click to enlarge

Klyuchevskoy - Sentinel 2 band image 12,11,8A from 03.15.2021 / 12:26 am via Mounts project

Klyuchevskoy - Sentinel 2 band image 12,11,8A from 03.15.2021 / 12:26 am via Mounts project

At Klyuchevskoy, a moderate flank explosive-effusive eruption and gas-vapor emission activity from the summit of Klyuchevskoy volcano continues.

KVERT satellite data showed a significant thermal anomaly on the flank eruption on the northwest slope of the volcano.

The color code for aviation remains orange.

 

Sources: KVERT & Mirova

Klyuchevskoy - high thermal anomalies at 03/16/2021 / 3:05 am - Doc. Mirova _MODIS_Latest10NTI

Klyuchevskoy - high thermal anomalies at 03/16/2021 / 3:05 am - Doc. Mirova _MODIS_Latest10NTI

Klyuchevskoy - 16.03.2021 / 07:40 - current activity on the flank  - webcam IVS FEB RAS KVERT

Klyuchevskoy - 16.03.2021 / 07:40 - current activity on the flank - webcam IVS FEB RAS KVERT

An eruption occurred at G. Sinabung, North Sumatra on March 15, 2021 at 18:08 h with an ash plume observed at ± 2,000 m above the summit (± 4,460 m above sea level) . The observable ash columns are gray, with a thick intensity, leaning towards the southwest and the west. This eruption is recorded by seismogram with a maximum amplitude of 15 mm and a duration of 6 min 27 sec.

 

Currently, Sinabung is in Activity Level 3 / siaga, with recommendations for society and visitors / tourists not to do activities on resettled villages, as well as locations within a 3 km radius of the summit. of Sinabung, as well as 5 km of sector radius for the south-eastern sector, and 4 km for the east-north sector.

 

Sources: PVMBG, Magma Indonesia and Komunitas Beidar Sinabung

Sinabung - eruptive plume of 03.15.2021 / 6:50 p.m. - PVMBG webcam

Sinabung - eruptive plume of 03.15.2021 / 6:50 p.m. - PVMBG webcam

Sinabung - the dome(s) this 03/16/2021 / 07:48 WIB - photo Firdaus Surbakti via Beidar Sinabung

Sinabung - the dome(s) this 03/16/2021 / 07:48 WIB - photo Firdaus Surbakti via Beidar Sinabung

In the Reykjanes Peninsula, as of March 15, a total of 1,800 earthquakes have been detected by the IMO seismic network, including seven M3.0 or more. The strongest M4.3 earthquakes occurred at 10:32 p.m. northeast of Fagradalsfjall Most of the earthquakes detected today were located near Fagradalsfjall and in the evening mostly northeast of Fagradalsfjall.

Between midnight and 5:43 am on March 16, around 500 earthquakes were detected in the Reykjanes peninsula, no earthquakes were measured above M3.0. The activity was mostly centered around Mt. Fagradalsfjall and east of Mt. Þorbjörn.

Reykjanes Peninsula in southwest Iceland and the strongest earthquakes - Sentinel image 3 / 03.14.2021 via Copernicus

Reykjanes Peninsula in southwest Iceland and the strongest earthquakes - Sentinel image 3 / 03.14.2021 via Copernicus

According to the latest InSAR document of Saturday March 13, there is an opening of 20 cm., and a progression of the dyke towards the southwest, in a line marked by the locations of the earthquakes.

Reykjanes - last InSAR document of 13.03.2021 indicating a widening and progression of the dyke towards the SO - Doc. IMO

Reykjanes - last InSAR document of 13.03.2021 indicating a widening and progression of the dyke towards the SO - Doc. IMO

Reykjanes Penisula - one of the many dykes exposed by erosion, illustrating what is happening underground today - photo dave McGarvie

Reykjanes Penisula - one of the many dykes exposed by erosion, illustrating what is happening underground today - photo dave McGarvie

Massive improvements have been made to the cGPS and seismic monitoring networks on the Reykjanes Peninsula. Many stations have been added, with the cooperation of ISOR, the Czech Academy of Sciences and the University of Cambridge with IMO.

 

Sources: IMO, ISOR

Reykjanes Peninsula - improvement of surveillance networks as of 15.03.2021 - Doc. via IMO - one click to enlarge

Reykjanes Peninsula - improvement of surveillance networks as of 15.03.2021 - Doc. via IMO - one click to enlarge

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

The 13th climax in a month at the southeastern crater of Etna occurred under heavy cloud cover on the night of March 14 to 15, 2021.

From the surveillance cameras from 20:10 UTC on 14.03.2021, the resumption of Strombolian activity at the Southeast crater is observed.

At the same time, Strombolian activity continues at the craters of Voragine, Bocca Nuova and the northeast crater.

The average amplitude of the volcanic tremor shows an increase reaching high values. The sources of the quake are located in the CSE at a depth of about 2.5 km asl.

Etna SEC - 13 ° paroxysme on 14-15.03.2021 - photo Boris Behncke

Etna SEC - 13 ° paroxysme on 14-15.03.2021 - photo Boris Behncke

Following a further increase in the mean amplitude of the volcanic tremor, the second level threshold is reached, the source being located in correspondence with the south-eastern crater at about 3000 m altitude.

Infrasound activity is also supported both in the rate of occurrence and in the energy of events.
The strombolian activity of the south-eastern crater has turned into a lava fountain. Due to the cloud cover, it is not possible to observe the activity in progress.

Etna SEC - 13 ° paroxysme on 14-15.03.2021 - photo Boris Behncke

Etna SEC - 13 ° paroxysme on 14-15.03.2021 - photo Boris Behncke

Etna SEC - 13 ° paroxysme on 14-15.03.2021 - photo Boris Behncke

Etna SEC - 13 ° paroxysme on 14-15.03.2021 - photo Boris Behncke

Around midnight, the National Institute of Geophysics and Volcanology, Etneo Observatory, reports that an overflow of lava is observed from the East zone of the SE Crater which extends towards the Valle del Bove.

In its report of 03.15 / 03.43 am, the INGV indicates that the activity of the lava fountain at the South-East crater is over. Moderate Strombolian activity persists and the lava flow that expands along the western slope of the Valle del Bove continues to be fed.
From the seismic point of view, the amplitude of the volcanic tremor has decreased, returning to average values. The source of the tremor is located near the SE crater at a depth of 2500 m above sea level.

Analysis of the clinometric data of the paroxysmal event showed variations at different stations, with cumulative maximum values ​​(less than 3 microradians) recorded at the Cratere del Piano (ECP) station. GNSS network data over the past few hours did not show
significant changes.

 

Source; INGV OE

Taal volcano island - image archives AFP / Ed JONES 02.26.2021

Taal volcano island - image archives AFP / Ed JONES 02.26.2021

In Taal, in the Philippine archipelago, the Phivolcs reports for the day from March 13 to 14 / 8 a.m. a total of 74 volcanic earthquakes, including 46 episodes of tremor of duration varying between 1 and 4 minutes.

The activity of the main crater consists of weak emissions of steam plumes at a height of ten meters.

The sulfur dioxide flow is measured at an average of 596 tonnes / day on March 13, 2021. The water temperature of the crater lake is measured at 71.8 ° C and the pH at 1.59 (at 04.03, 2021)

 

From March 14 to 15/8 a.m., a total of 252 volcanic earthquakes are recorded, including 17 tremor episodes and 5 hybrid events.

The deformation parameters reflect a slow and constant inflation and expansion of the Taal region since the eruption of January 2020, and indicate increasing magmatic activity at shallow depth.

Level 2 / Increased Unrest  is maintained.

 

Source: Phivolcs

Bagana - Thermal anomalies at 03/13/2021 / 00h18 - image Sentinel-2 bands 12.11.8A / MIROVA MODIS thermal activity Last

Bagana - Thermal anomalies at 03/13/2021 / 00h18 - image Sentinel-2 bands 12.11.8A / MIROVA MODIS thermal activity Last

Bagana - Thermal anomalies from mid-February to mid-March - Doc. Mirova Modis

Bagana - Thermal anomalies from mid-February to mid-March - Doc. Mirova Modis

The eruptive phase, which began in Bagana, on Bougainville Island in Papua New Guinea in February 2000, continues, characterized by thermal anomalies identified on March 8-9, with 35 MW max. and March 11-13, with 25 MW max.

 

The Bagana volcano, which occupies a remote part of central Bougainville Island, is one of the youngest and most active volcanoes in Melanesia. This massive symmetrical cone was largely constructed by an accumulation of viscous andesitic lava flows. The entire edifice could have been built in about 300 years at its current rate of lava production. Eruptive activity is frequent and characterized by a non-explosive effusion of viscous lava that maintains a small lava dome in the summit crater, although explosive activity occasionally producing pyroclastic flows also occurs. The lava flows form spectacular, freshly preserved tongue-shaped lobes up to 50m thick with prominent dikes running down the flanks on all sides.

 

Sources: Mirova, Mounts project, Sentinel-2 and Global Volcanism Program

Bagana - image Sentinel 4,3,2 & bands12,11,8A from 13.03.2021 - via Mounts project

Bagana - image Sentinel 4,3,2 & bands12,11,8A from 13.03.2021 - via Mounts project

Yesterday March 14, 2021, just over 3,000 earthquakes were located on the Reykjanes Peninsula.

The largest M5.4 earthquake was measured just west of Nátthagi at 2:15 p.m. It was widely felt, north of Sauðárkrókur and east of Vestmannaeyjar.

Twenty-eight earthquakes greater than M3.0 were counted, mostly south of Mount Fagradalsfjall, but just under 10 earthquakes greater than M3.0 were scattered west towards the Blue Lagoon.

 

Source: IMO

Reykjanes Peninsula - location and magnitude of earthquakes as of 15.03.2021 / 08:10 - Doc. IMO
Reykjanes Peninsula - location and magnitude of earthquakes as of 15.03.2021 / 08:10 - Doc. IMO
Reykjanes Peninsula - location and magnitude of earthquakes as of 15.03.2021 / 08:10 - Doc. IMO

Reykjanes Peninsula - location and magnitude of earthquakes as of 15.03.2021 / 08:10 - Doc. IMO

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
Popocatépetl - exhalation of 13.03.2021 / 06:14 - webcams of Mexico / Cenapred

Popocatépetl - exhalation of 13.03.2021 / 06:14 - webcams of Mexico / Cenapred

Popocatépetl - exhalation of 13.03.2021 / 07:19 - webcams of Mexico / Cenapred

Popocatépetl - exhalation of 13.03.2021 / 07:19 - webcams of Mexico / Cenapred

During the last 24 hours, thanks to the monitoring systems of the Popocatépetl volcano, 63 exhalations and 487 minutes of tremor have been identified, accompanied by emissions of water vapor, volcanic gases and small amounts of ash.

Based on information from the National Communications Center (CENACOM), yesterday a slight fall of ash was reported in the municipalities of Amecameca and Tlalmanalco around 22:50.

Meanwhile, a constant emission of water vapor, gas and small amounts of ash is observed, which is dispersed in a north-westerly (NW) direction.

The recent flyby confirms that there was no lava dome inside the crater.

The volcanic alert remains at amarillo Fase 2.

 

Sources: Cenapred and webcams of Mexico

Pacaya - ash plume on 03.13.2021 - Doc. Insivumeh

Pacaya - ash plume on 03.13.2021 - Doc. Insivumeh

Pacaya - ash plume and lava flow on 03.13.2021 - Conred video screenshot

Pacaya - ash plume and lava flow on 03.13.2021 - Conred video screenshot

The Pacaya maintains a high level of activity, with bursts of explosions, accompanied by plumes of gas and ash up to 4,500 meters asl. moving southwest and south, for 30 km.

Expulsions of ballistic materials are observed up to 400 meters above the pit.

The active lava flow on the southern flank has a length of 1,500 meters. Blocks falls are generated from the lava front.

Ash falls are possible on El Patricinio, San José El Rodeo, Los Pacitos, Pacaya and Finca El Chupadero.

The Conred invites the municipalities of San Vicente Pacaya and Villa Canales to close access to the flanks of the volcano, and recalls that the Pacaya National Park must continue to prohibit access to areas of active lava flows.

 

Sources: Insivumeh & Conred

Sinabung - the summit and the dome on 03.13.2021 - photo Firdaus Surbakti

Sinabung - the summit and the dome on 03.13.2021 - photo Firdaus Surbakti

A white plume with a strong thickness is observed this March 13 at about 50 to 700 meters from the summit of Sinabung.

Seismicity is characterized by:

- 1 eruption earthquake, with an amplitude of 26 mm, and the duration of the earthquake was 277 seconds.
- 47 collapse / avalanche earthquakes, with an amplitude of 2-34 mm and the earthquake lasted 20-130 seconds.
- 14 emission earthquakes
- 21 low frequency earthquakes.
- 102 hybrid / multiphase earthquakes
- 4 local tectonic earthquakes
- 2 remote tectonic earthquakes.

The dome (s) is (are) constantly evolving, and these photos differ depending on the point of view.

 

Sources: PVMBG, Magma Indonesia, the photographers cited.

Sinabung - the dome from various points of view on 03.11.2021 - photos Endro Rusharyanto - one click to enlarge the thumbnailsSinabung - the dome from various points of view on 03.11.2021 - photos Endro Rusharyanto - one click to enlarge the thumbnails
Sinabung - the dome from various points of view on 03.11.2021 - photos Endro Rusharyanto - one click to enlarge the thumbnailsSinabung - the dome from various points of view on 03.11.2021 - photos Endro Rusharyanto - one click to enlarge the thumbnails

Sinabung - the dome from various points of view on 03.11.2021 - photos Endro Rusharyanto - one click to enlarge the thumbnails

In the Reykjanes Peninsula, today March 14, more than 700 earthquakes have been automatically located. The two largest at 01:19 from M3.7 to SW-Fagradalsfjall and at 04:40 from M4.2 in the same area.

Yesterday, around 2,600 earthquakes were detected. The biggest earthquake occurred at 1:34 am on M4.6. by the southwest end of Mt. Fagradalsfjall, it was widely felt, on the Reykjanes peninsula, north of Borganes and east of Fljótshlíð. In the evening at 10:06 p.m., an earthquake from an M4.1 was also measured by Mt. Fagradalsfjall.

Reykjanes Peninsula - location and magnitude of earthquakes as of 14.03.2021 / 08:20 - Doc.IMO
Reykjanes Peninsula - location and magnitude of earthquakes as of 14.03.2021 / 08:20 - Doc.IMO
Reykjanes Peninsula - location and magnitude of earthquakes as of 14.03.2021 / 08:20 - Doc.IMO

Reykjanes Peninsula - location and magnitude of earthquakes as of 14.03.2021 / 08:20 - Doc.IMO

It is important to keep track of activity in the southern region of Mt. Fagradalsfjall to assess whether the dike is expanding to the south.
The latest satellite images and GPS data show that the magma buildup is concentrated at the southern end of the dike under Mt. Fagradalsfjall. It is currently the most likely site for a possible eruption.

According to the Meteorological Bureau's lava flow model yesterday, a fissure is located where the magma tunnel is in Nátthaga, near Fagradalsfjall.
"There are two possibilities: no eruption or eruption ... as the magma and the corridor lengthens towards the south, we have to prepare for it to start to erupt, but that is not certain. . ", according to Magnús Tumi Guðmundsson, professor of geophysics in an interview with mbls.

 

Sources: IMO & mbls

Everything seems calm in Nátthaga (probable site of the potential eruption - on the webcam), but in the basement, things are moving!
Everything seems calm in Nátthaga (probable site of the potential eruption - on the webcam), but in the basement, things are moving!

Everything seems calm in Nátthaga (probable site of the potential eruption - on the webcam), but in the basement, things are moving!

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Publié dans : #volcanic activity, #Sismologia

Sinabung in March :

According to the Darwin VAAC, an ash plume has been identified in satellite images as high as 3 km (10,000 feet) above sea level. (i.e. 600 m above the summit) and drift NW on March 5. The observatory noted that avalanches of material traveled 500m along the southeastern flank from March 6 to 7 and that an ash plume rose 1 km and drifted northwest at 19 10:10 am on March 7.

The lava domes atop Sinabung, in partly new, appear to have developed at two points, with potential for collapse generation in 2 different directions.

Sinabung - 03.10.2021 / 11:49 am - photo Nachelle Homestay

Sinabung - 03.10.2021 / 11:49 am - photo Nachelle Homestay

Sinabung - evolution of the dome - top photo: 10.03.2021 / 11:09 am / Nachelle homestay - bottom photo: 10.03.2021 / Sadrah Peranginangin
Sinabung - evolution of the dome - top photo: 10.03.2021 / 11:09 am / Nachelle homestay - bottom photo: 10.03.2021 / Sadrah Peranginangin

Sinabung - evolution of the dome - top photo: 10.03.2021 / 11:09 am / Nachelle homestay - bottom photo: 10.03.2021 / Sadrah Peranginangin

The seismicity on March 10 is characterized by:

- 3 eruption earthquakes, with an amplitude of 25 to 94 mm, and the duration of the earthquake was 183 to 341 seconds.
- 52 collapse / avalanche earthquakes, with an amplitude of 2-120 mm and the earthquake lasted 17-180 seconds.
- 10 blast / emission earthquakes
- 6 low frequency earthquakes
- 22 hybrid / multiphase earthquakes
- 1 episode of non-harmonic tremor, with an amplitude of 5 mm, and the duration of the earthquake was 898 seconds.

Sinabung - 03.10.2021 / 11:48 - photo Sadrah Peranginangin via Komunitas Beidar Sinabung

Sinabung - 03.10.2021 / 11:48 - photo Sadrah Peranginangin via Komunitas Beidar Sinabung

Sinabung - 03.10.2021 / 11:10 pm - photo Endro Rusharyanto

Sinabung - 03.10.2021 / 11:10 pm - photo Endro Rusharyanto

This March 11, 2021, at 09:22 WIB, a pyroclastic avalanche flow was observed, moving 3,000 meters to the southeast.

The alert level remained at 3 (on a scale of 1 to 4), with a general exclusion zone of 3 km and extensions to 5 km in the SE sector and 4 km in the NE sector.

 

Sources: PVMBG, Magma Indonesia, Beidar Sinabung, Endro Lewa (Awel Ordne), Nachelle Homestay, Global Volcanism Pogram weekly report.

Sinabung - 03.11.2021 / 09:22 - photo Alin dari Naman Teran via Komunitas Beidar Sinabung

Sinabung - 03.11.2021 / 09:22 - photo Alin dari Naman Teran via Komunitas Beidar Sinabung

Sinapred reports that a series of five moderate to strong vulcanian-type explosions occurred on March 9, 2021 at the San Cristobal volcano, Nicaragua, between 1:06 p.m. and 1:32 p.m. local time.
The strongest eruption at 1:25 p.m. local time was observed for 20 minutes and generated a dense, dark ash column at an estimated altitude of 2,400 m, which extended about 17 km southwest of the volcano. Ash falls were reported in the towns of El Viejo, Chinandega and Chichigalapa, severely reducing visibility there.

The last activity of the volcano dates back to March 2019 (GVP) ... a new eruptive cycle could begin in 2021.

 

Sources: Ineter, Sinapred and local media

San Cristobal - 03.09.2021 - doc. Ineter

San Cristobal - 03.09.2021 - doc. Ineter

San Cristobal - 03.10.2021 / 06:20 San Cristobal - Webcam Ineter

San Cristobal - 03.10.2021 / 06:20 San Cristobal - Webcam Ineter

Sabancaya's activity between March 1 and 7 was maintained at a moderate level, with an average of 85 explosions per day, accompanied by plumes of ash and gas up to 2,000 meters above the summit.

During this period, I.G. Peru recorded 1,867 earthquakes of volcanic origin, associated with the circulation of internal fluids. The VT earthquakes, related to the fracturing of rocks, occurred mainly to the southeast and northeast of the volcano, of magnitude between 2.1 and 2.6.

The slight inflation of the Hualca Hualca volcano, northern sector, is still observed.

The volcanic alert remains in Naranja, with an inaccessible area of ​​12 km in radius.

 

Source: I.G.P.

Sabancaya - activity between March 1 and 7, 2021 - Doc. I.G. Peru

Sabancaya - activity between March 1 and 7, 2021 - Doc. I.G. Peru

Scientists are closely monitoring the magma channel that has formed between Keilir and Fagradalsfjall on the Reykjanes Peninsula.

The magma chamber is only about a meter wide but about 7 kilometers long and has moved two to three kilometers south over the past two weeks as the magma entered it. At the bottom of the magma chamber, at a depth of about five kilometers, there is a channel and from there flows about 15 to 20 cubic meters per second upwards, about three to four times the average flow of the Elliðaán rivers. The magma chamber is estimated to be about one kilometer from the earth's surface on the south side, but about two kilometers at Keilir. The lava on the south side is also hotter and therefore more likely that the magma will rise to the surface.If the magma continues to flow into the magma chamber, it goes without saying that it will expand and seek out the magma where it is. find the least obstacle. It will probably continue to expand southwards or the magma will rise to the surface.

It is therefore the southern end that is under study, due to seismic activity and crustal movements show that there has been most of the changes in recent days, ”explains Freysteinn Sigmundsson, geophysicist at the University of Iceland Earth Institute.
If there is an eruption, Freysteinn says it can be similar in size to the Fimmvörðuháls eruption, and he bases that on the flow of magma flowing through the magma tunnel. In fact, it can happen at any time and without much warning.

Reykjanes Peninsula - shematic description of the dyke between Keilir and Fagradalsfjall - warmer and closer to the surface at SW (left) - Doc. RUV - one click to enlarge

Reykjanes Peninsula - shematic description of the dyke between Keilir and Fagradalsfjall - warmer and closer to the surface at SW (left) - Doc. RUV - one click to enlarge

On March 10, around 2,500 earthquakes were detected in the Reykjanes Peninsula. About 30 of these were of magnitude M3.0 and above, the largest of which was M5.1 at 3:14.

About 800 earthquakes have been detected since midnight. The largest was M3.4 magnitude at 2:10 a.m.

 

Sources: IMO and local press

Reykjanes Peninsula - number and magnitude of earthquakes as of 11.03.2021 / 8:30 am - Doc. IMO
Reykjanes Peninsula - number and magnitude of earthquakes as of 11.03.2021 / 8:30 am - Doc. IMO

Reykjanes Peninsula - number and magnitude of earthquakes as of 11.03.2021 / 8:30 am - Doc. IMO

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

Strombolian activity resumed at the level of the SE crater of Etna on March 9, 2021. As for the average amplitude of the volcanic tremor from 17:30 GMT, there is an increase, which for the moment remains in average values -high. The source of the quake is located at the SE Crater at a depth of about 2,500 meters above sea level.

The infrasound activity also increases and is localized in the SE crater. Data from GNSS soil deformation monitoring networks and clinometry show no significant changes.

Etna - resumption of Strombolian activity 09.03.2021 / 6:19 pm - INGV OE webcam

Etna - resumption of Strombolian activity 09.03.2021 / 6:19 pm - INGV OE webcam

Scenes documented by the INGV-Osservatorio Etneo surveillance camera show simultaneous explosions at the Voragine crater and the southeast crater. March 9, 2021 in the evening

From the surveillance cameras, from around 19:13 UTC, an overflow of lava can be observed from the SE crater towards the Valle del Bove.

From 20:00 UTC, there is an increase in strombolian activity at the CSE, accompanied by the emission of ash which rapidly disperses in the atmosphere towards the NE. The lava flow continues to be fed and the front is at an altitude of about 2900 meters above sea level advancing towards the Valle del Bove.

The intracrateric explosive activity at the summit craters continues.

Etna SEC - strombolian activity and lava flow in the Valle del bove 09.03.2021 / 20h58 - LAVE webcam

Etna SEC - strombolian activity and lava flow in the Valle del bove 09.03.2021 / 20h58 - LAVE webcam

The mean amplitude of the volcanic tremor showed a further increase, reaching high values; the sources of the quake are in the CSE at a depth of about 3000 meters above sea level.

After a short return phase, the average amplitude of the volcanic tremor, from 9:30 p.m. GMT, began to increase again to reach the second level threshold, with the Strombolian activity located at the southeast crater, which increases to a lava fountain; the lava flow is fed and reached an altitude of about 2200 meters above sea level. Due to cloud cover, it is not possible to observe the ongoing activity continuously.

Etna - last tremor diagram on 10.03.2021 - Doc. INGV OE - one click to enlarge

Etna - last tremor diagram on 10.03.2021 - Doc. INGV OE - one click to enlarge

Etna SEC - Strombolian activity and lava flow in the Valle del bove on 03.10.2021 / 00:28 Etna - LAVE webcam

Etna SEC - Strombolian activity and lava flow in the Valle del bove on 03.10.2021 / 00:28 Etna - LAVE webcam

The activity of the lava fountain at the southeast crater ended at 03:30 UTC, the lava emission that is developing along the western slope of the Valle del Bove continues to be moderately fed and at the time the lava front reached the altitude of about 1800 m asl.
From the seismic point of view, the amplitude of the volcanic tremor has returned to average values.

 

Source: INGV OE

Etna - end of paroxysm - LAVE webcam 03.10.2021 / 03h58

Etna - end of paroxysm - LAVE webcam 03.10.2021 / 03h58

Clear satellite images of the 03/07/2021 eruption showed ash emissions from the small cone in the Veniaminof summit caldera, in addition to the probable lava eruption from a vent at ~ 1 km (0.6 miles ) east of the top of the cone on the flank cone under the intracaldera glacier.
This activity produces incandescence and greatly elevated surface temperatures, as well as a small plume of steam and meltwater. A low-level plume of volcanic ash and gas is likely continuing and has been observed by pilots, as well as web cameras and satellite imagery during periods of clear weather over the past day. The ash and gas plume was below 10,000 feet asl yesterday and was not observed in cloudy conditions overnight or this morning. The plume extended up to 150 km (93 miles) northeast yesterday afternoon, but the ashfall is mostly confined to the summit caldera near the vent. No ash fall has been reported in neighboring communities.

 

Source: AVO

Veniaminof - 07.03.2021 / 07:29 UTC - DOC. Planet via AVO

Veniaminof - 07.03.2021 / 07:29 UTC - DOC. Planet via AVO

In the Reykjanes Peninsula, around 5:20 a.m. on March 9, 2021, increased seismic activity was detected in the southernmost part of the magma passage beneath Fagradalsfjall. A tremor pulse was detected at around the same time and lasted until about 7 a.m. This probably means that the passage of magma is developing towards the SW. Since then, there has been regular activity of small earthquakes.

 

 

The latest satellite images, GPS measurements and models all indicate that the flow of magma has diminished since the start of last week. Still, the magma is close to the surface and we have to continue to assume that an eruption could occur. If the magma passage continues to grow over the next few days and weeks, we might also expect earthquake waves similar to that of the weekend, which was powerful enough to destabilize the people of Grindavík.

 

Experts still assume that one of the four scenarios is the most likely:
- Seismic activity will decrease in the days or weeks to come
- Activity will increase with larger earthquakes, up to M6 by Fagradalsfjall
- An earthquake of up to M6.5 will come from Brennisteinsfjöll.
- The magma intrusion at Fagradalsfjall continues, leading ... either to a diminishing magma flow, with magma cooling and hardening, or to a fissure eruption and lava flow that will probably not threaten inhabited areas.

Reykjanes Peninsula - The red line marks the magma intrusion (dike) below the area between Fagradalsfjall and Keilir. Gray areas indicate places where tension release earthquakes can occur - Doc. IMO 09.03.2021 via Kristín Jónsdóttir

Reykjanes Peninsula - The red line marks the magma intrusion (dike) below the area between Fagradalsfjall and Keilir. Gray areas indicate places where tension release earthquakes can occur - Doc. IMO 09.03.2021 via Kristín Jónsdóttir

At 23:01, an earthquake of M4.0 occurred in Fagradalsfjall, a few minutes later another of M3.7 followed. They were felt in the southwest of Iceland.

At 6:45 p.m. last night, the frequency of minor earthquakes increased but no sign of a volcanic tremor was detected. A few earthquakes of magnitude greater than M3.0 were detected during this activity, the largest one M3.4 at 8:40 p.m.

 

Sources: IMO, Iceland Review, Icelandic volcanoes, mbls

Reykjanes Peninsula - location and magnitude of earthquakes as of 10.03.2021 / 08:25 - Doc. IMO
Reykjanes Peninsula - location and magnitude of earthquakes as of 10.03.2021 / 08:25 - Doc. IMO
Reykjanes Peninsula - location and magnitude of earthquakes as of 10.03.2021 / 08:25 - Doc. IMO

Reykjanes Peninsula - location and magnitude of earthquakes as of 10.03.2021 / 08:25 - Doc. IMO

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Publié le par Bernard Duyck
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Popocatépetl - overflight of the crater on 03.05.2021 - photos Cenapred / CNPC / Seguridad
Popocatépetl - overflight of the crater on 03.05.2021 - photos Cenapred / CNPC / Seguridad

Popocatépetl - overflight of the crater on 03.05.2021 - photos Cenapred / CNPC / Seguridad

During the last 24 hours, thanks to the monitoring systems of the Popocatépetl volcano, 82 exhalations and 234 minutes of tremor have been identified, accompanied by emissions of water vapor, volcanic gases and small amounts of ash.
Since March 6 in the morning, we observe an intermittent emission of volcanic gases and sometimes ash, which disperse in an east-south-east direction.


As part of the monitoring of the Popocatépetl volcano, expert staff from the Institute of Geophysics of the National Autonomous University of Mexico (UNAM) and the National Center for Disaster Reduction (CENAPRED), carried out an overview, with the support of the National Guard, yesterday March 5, 2021.

It has been observed that the inner crater maintains a diameter of 360-390 meters and an approximate depth of 150-180 meters, which is covered with various fragmented materials (tephra). Likewise, it was confirmed that there was no lava dome inside the crater.

 

Volcanic alert remains at Amarillo Fase 2

 

Source: Cenapred

Popocatépetl - overflight of the summit on 03.05.2021 - photo Cenapred / CNPC / Seguridad

Popocatépetl - overflight of the summit on 03.05.2021 - photo Cenapred / CNPC / Seguridad

At Etna, from around 1.00 UTC, a small lava flow is observed emitted by the effusive vent which opened on March 4, 2021 at the base of the SE crater. At the same time, the resumption of Strombolian activity at the level of the SE crater is also observed.

Strombolian activity continues confined to the craters of Voragine, Bocca Nuova and and NE.
Also from 1.00 UTC there is an increase in the volcanic tremor which at the moment is on medium-high values. The source of the tremor is located near the SE crater. Infrasound events are few in number and low in energy.

From 01:30 UTC there is a further rapid increase in the amplitude of the volcanic tremor which is currently at high values. The source of the tremor is located near the SE crater.

Etna SEC - strombolian activity on 07.03.2021 / 04h18 - INGV OE webcam

Etna SEC - strombolian activity on 07.03.2021 / 04h18 - INGV OE webcam

From around 03:30 UTC, there is an increase in Strombolian activity at the SE crater.
The activity forms an eruptive cloud which reaches a height of about 5000 m above sea level. dispersing towards E. Regarding the lava flow, the front is about 2900 m above sea level.

A lava overflow from the eastern slope of the SEC is observed from approximately 03:50 UTC. The lava flow produced by the effusive vent at the base of the CSE is still fed and its front reached an altitude of about 2800 m above sea level.

From 4:20 UTC there is a further rapid increase in the amplitude of the volcanic tremor which is currently at high values. The source of the tremor is located near the SE crater.

Etna - tremor at 07.03.2021 - 10 ° paroxysm - Doc. INGV OE

Etna - tremor at 07.03.2021 - 10 ° paroxysm - Doc. INGV OE

From around 06:00 UTC, the Strombolian activity at the SE crater (SEC) passed through a lava fountain and from 06:20 UTC, it formed an eruptive column which has now exceeded the height of 10,000 m above sea level. . dispersing eastward. As for the lava flows, which develop in the Valle del Bove, due to the cloud cover, it is not possible to make observations to estimate the share of the fronts.
The volcanic tremor of the last half hour reached a very high average amplitude and is constantly located near the SE crater
The number and energy of infrasound events are high and their locations are in the crater of the SEC.

From around 07:20 UTC, the SE Crater lava fountain ceased.

 

Source: INGV OE

Etna SEC - 2021.03.07, respectivement à 07h12 et 07h39 - webcam INGV OE - one click to enlargeEtna SEC - 2021.03.07, respectivement à 07h12 et 07h39 - webcam INGV OE - one click to enlarge

Etna SEC - 2021.03.07, respectivement à 07h12 et 07h39 - webcam INGV OE - one click to enlarge

The ICE-SAR rescue teams took advantage of the good weather this Saturday, March 6 to install a new VHF repeater at the top of the mountain in order to obtain better radio coverage in the area affected by the seismic swarm and a potential eruption on the Reykjanes Peninsula.

Reykjanes Peninsula - installation of a new VHF relay by local ICE-SAR teams - photo via Gisli Olafsson

Reykjanes Peninsula - installation of a new VHF relay by local ICE-SAR teams - photo via Gisli Olafsson

Just after midnight at 12:22 am on March 07, 2021, a tremor was detected which lasted 20 minutes. This tremor was similar to that measured on March 3, which had lasted several hours.

Following these events the seismicity intensified with earthquakes of more than 4. The biggest earthquake of the night was M5 at 2:02 am about 3 km west of Fagradalsfjall. As of midnight, more than 30 earthquakes on M3 have been located and 5 larger than M4.
More than 22,000 earthquakes have been detected in the region since the start of the activity.

 

Sources: IMO & Gisli Olafsson

Reykjanes Peninsula - location and magnitude of earthquakes at 07.03.2021 / 07:35 - Doc. IMO
Reykjanes Peninsula - location and magnitude of earthquakes at 07.03.2021 / 07:35 - Doc. IMO
Reykjanes Peninsula - location and magnitude of earthquakes at 07.03.2021 / 07:35 - Doc. IMO

Reykjanes Peninsula - location and magnitude of earthquakes at 07.03.2021 / 07:35 - Doc. IMO

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