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Earth of fire

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

volcanic activity

Publié le par Bernard Duyck
Publié dans : #volcanic activity
 Piton de La Fournaise - the eruptive fissure at dawn 10 april - photo OVPF

Piton de La Fournaise - the eruptive fissure at dawn 10 april - photo OVPF

Piton de La Fournaise - the flow evolves according to the topography - photo 10.04.2021 / IPR

Piton de La Fournaise - the flow evolves according to the topography - photo 10.04.2021 / IPR

The eruption that began on 04/09/2021 at 7 p.m. (appearance of the tremor) at Piton de La Fournaise continues. The intensity of the volcanic tremor (indicator of the intensity of the eruption), after a relatively stable phase on the day of 04/10/2021, has been declining gradually since 9 a.m. local time on April 11.

Following an overview of the eruptive site carried out this morning with the assistance of the SAG and the PGHM, the eruptive fissure could be located with precision, 700 m southwest of the Château Fort crater. During the flyby, around 8:40 a.m. local time, activity focused on two main eruptive vents in which several regimes of lava fountains were observed. The upstream part of the crack is no longer active. The lava fountains did not exceed thirty meters in height

The flow had traveled about a mile to the east and the flow front, consisting of aa lava, was spreading very slowly. It was this morning at 8:40 am around 1800 m altitude.

Piton de La Fournaise - 04.11.2021 / 7:30 am - photo OVPF

Piton de La Fournaise - 04.11.2021 / 7:30 am - photo OVPF

Piton de La Fournaise - 04.11.2021 / 9.47am - IRT webcam - OVPF

Piton de La Fournaise - 04.11.2021 / 9.47am - IRT webcam - OVPF

The eruption continues on April 12. The intensity of the volcanic tremor (indicator of the intensity of the eruption), despite some fluctuations, remains relatively stable

Over the last 24 hours, 93 superficial volcano-tectonic earthquakes (between sea level and surface) have been recorded under the summit craters.

Piton de La Fournaise - Evolution of the RSAM (indicator of the volcanic tremor and the intensity of the eruption) since 04/09/2021 on the FOR seismological station located at the Château Fort crater (© OVPF-IPGP).

Piton de La Fournaise - Evolution of the RSAM (indicator of the volcanic tremor and the intensity of the eruption) since 04/09/2021 on the FOR seismological station located at the Château Fort crater (© OVPF-IPGP).

Piton de La Fournaise - 11.04.2021 / 08:50 loc. - lava sampling - photo OVPF-IPGP

Piton de La Fournaise - 11.04.2021 / 08:50 loc. - lava sampling - photo OVPF-IPGP

InSAR satellite data shows that the deformations, in the order of decimeter, linked to the injection of magma towards the eruptive site have remained confined inside the Enclos Fouqué caldera. These data are in good agreement with the data recorded on the permanent GPS stations of the OVPF-IPGP which recorded up to 40 cm of deformation in the area of ​​the Château Fort crater.

Piton de La Fournaise - The above interferogram shows the deformation of the surface associated with the eruption of April 9, 2021. Each complete color cycle (from red to blue) of the interferogram corresponds to 27.8 mm of displacement of the surface towards (positive) or against (negative) of the Sentinel-1 satellite (the direction of which is represented by the arrow “LOS” at the top right of the figure). (© LMV-OPGC-OVPF-IPGP)

Piton de La Fournaise - The above interferogram shows the deformation of the surface associated with the eruption of April 9, 2021. Each complete color cycle (from red to blue) of the interferogram corresponds to 27.8 mm of displacement of the surface towards (positive) or against (negative) of the Sentinel-1 satellite (the direction of which is represented by the arrow “LOS” at the top right of the figure). (© LMV-OPGC-OVPF-IPGP)

Satellite data also made it possible to trace the precise outline of the lava flow. On April 11, around 7 p.m. local time, the flow had traveled since the start of the eruption about 3.2 km and the flow front was located at the level of the Grandes Pentes broken (around 1690 m above sea level), like this was visible on the OVPF-IPGP webcam located in Piton des Cascades

The NOVAC data from the OVPF-IPGP stations since April 9 indicates a moderate SO2 emission rate, between 2 and 4 kilotons / day at most. With regard to the composition of emissions at Piton de la Fournaise, this is equivalent to a surface flow of the order of 10-25 m³ / s.

 

Source: OVPF

Piton de La Fournaise - 04.11.2021 / 1 p.m. - photo OVPF-IPGP

Piton de La Fournaise - 04.11.2021 / 1 p.m. - photo OVPF-IPGP

Piton de La Fournaise - 04.11.2021 / 6:17 p.m. - IRT webcam - OVPF

Piton de La Fournaise - 04.11.2021 / 6:17 p.m. - IRT webcam - OVPF

Piton de La Fournaise - 11.04.2021 / 6:20 pm UT - the flow front at the level of the large slopes - Camera Cascades OVPF

Piton de La Fournaise - 11.04.2021 / 6:20 pm UT - the flow front at the level of the large slopes - Camera Cascades OVPF

Scientific update on the Soufrière de St. Vincent eruption of 11.04.21 / 9h - UWI-SRC

During the last twelve hours, episodes of tremor lasting up to 20 minutes have continued to be recorded.
The intervals between the tremor episodes were 1.5 to 3 hours.
Based on visual observations and satellite imagery, the intervals are associated with periods of explosive activity or enhanced ventilation.
Thunder and lightning were felt during these times.

Heavy ash falls were observed at Belmont Observatory throughout the night.
Ash also reportedly occurred in most parts of the island overnight and in neighboring islands: the Grenadines, Barbados and Saint Lucia.

Soufrière de St. Vincent - Copernicus images from 09 and 10.04.2021 (top) and from 10.04.2021 / 16:42 UTC - ash on SVG and Barbados (bottom) - NASA image NOAA VIIRS NPP
Soufrière de St. Vincent - Copernicus images from 09 and 10.04.2021 (top) and from 10.04.2021 / 16:42 UTC - ash on SVG and Barbados (bottom) - NASA image NOAA VIIRS NPP

Soufrière de St. Vincent - Copernicus images from 09 and 10.04.2021 (top) and from 10.04.2021 / 16:42 UTC - ash on SVG and Barbados (bottom) - NASA image NOAA VIIRS NPP

Soufrière de St. Vincent - ash falls at the belmont observatory & weight of ashes on the tree branches, with threat of rupture - photos R.Robertson 04.11.2021 - one click to enlargeSoufrière de St. Vincent - ash falls at the belmont observatory & weight of ashes on the tree branches, with threat of rupture - photos R.Robertson 04.11.2021 - one click to enlarge

Soufrière de St. Vincent - ash falls at the belmont observatory & weight of ashes on the tree branches, with threat of rupture - photos R.Robertson 04.11.2021 - one click to enlarge

Soufrière de St. Vincent - roofs collapsed under the weight of ash in the north of the island - photo 04.11.2021 / Flash Hurricanes Météo Antilles

Soufrière de St. Vincent - roofs collapsed under the weight of ash in the north of the island - photo 04.11.2021 / Flash Hurricanes Météo Antilles

Soufrière - Volcanic ash advisory of 11.04.2021 - Doc. VAAC Washington

Soufrière - Volcanic ash advisory of 11.04.2021 - Doc. VAAC Washington

Explosions and accompanying ash fall of a similar or greater magnitude will likely continue to occur over the next few days.

 

Sources: UWI-SRC & NEMO SVG

Soufrière de St. Vincent - last report of ERCC / european Comission 09.04.2021

Soufrière de St. Vincent - last report of ERCC / european Comission 09.04.2021

About 3,200 people took refuge in 78 government-run shelters, and four empty cruise ships stood ready to take other evacuees to neighboring islands, with a group of more than 130 already taken to St. Lucia. Those staying in the shelters were tested for COVID-19, with anyone who tested positive being taken to an isolation center.
Neighboring countries, including Antigua and Grenada, have also offered to host the evacuees.
The ashes forced the cancellation of several flights and poor visibility limited evacuations in some areas. Officials have warned that Saint Lucia to the north and Grenada to the south could have slight ashfall, though most of it were to head northeast into the Atlantic Ocean.


Source: AP / 10.04.2021

Reykjanes Peninsula - the 4 eruptive sites active on 04.11.2021 / 04:37 - mbls webcam - note the presence of a fox which remains at a distance from the lava - a click to enlarge

Reykjanes Peninsula - the 4 eruptive sites active on 04.11.2021 / 04:37 - mbls webcam - note the presence of a fox which remains at a distance from the lava - a click to enlarge

In the Reykjanes peninsula, the eruption at the start of the 4 active sites does not weaken.

The gas pollution caused by the eruption will cover the colonies of Suðurnes this April 11, according to the gas pollution forecasts of the IMO.

"It is a southeasterly windy night so the gaseous pollution is blowing towards Reykjanesbær, Garður and Sandgerði and over the north-western part of the Reykjanes peninsula today. Tonight the pollution is expected to go straight to it. west, which is a fairly uninhabited area. Tomorrow it should be laid again on the northwestern part of the Reykjanes peninsula, "says a meteorologist on duty at the Icelandic meteorological office.
"It is particularly important for people with a sensitive respiratory system to avoid straining during pollution."

Reykjanes Peninsula- the Meradalur site surrounded too closely by visitors - note the "reservoir" formed near the cone which can suddenly release large amounts of lava - photo SkyAlert

Reykjanes Peninsula- the Meradalur site surrounded too closely by visitors - note the "reservoir" formed near the cone which can suddenly release large amounts of lava - photo SkyAlert

Caution is strongly recommended to people who go near the lava, and who break into any common sense, between two arms of flow, being able to let out at any time a packet of molten lava, or collapse .

 

Sources: IMO, RUV, mbls.

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
 Explosive eruption of Soufrière of St. Vincent - Day 1 - photos volcanoesintheworld

Explosive eruption of Soufrière of St. Vincent - Day 1 - photos volcanoesintheworld

Continuation of the explosive eruptive phase at La Soufrière in St. Vincent:

The ash thickness of the last 24 hours of eruptive activity ranged from <1 mm at Colonaire (~ 12.5 km from the volcano) to 10-15 mm at Rabacca (~ 7.4 km from the volcano).
Ash thickness and grain size generally increased from Kingstown north to the volcano. Ash falls have been reported in parts of Barbados and Saint Lucia.
The volcano has entered an explosive eruptive phase that could continue over the next few days and weeks. The explosions are expected to be of a similar or greater magnitude.

Ash of the eruptions  over St. Vincent and Barbados - image 04/10/2021 / 4:42 p.m. UYC NASA NOAA VIIRS NPP

Ash of the eruptions over St. Vincent and Barbados - image 04/10/2021 / 4:42 p.m. UYC NASA NOAA VIIRS NPP

Eruptions de la Soufrière - ash covers the island - photos St. Vincent and the Grenadines and R.Robertson (pluricentimetric slag samples on the Rabacca river area more than 7 km from the volcano) - one click to enlarge
Eruptions de la Soufrière - ash covers the island - photos St. Vincent and the Grenadines and R.Robertson (pluricentimetric slag samples on the Rabacca river area more than 7 km from the volcano) - one click to enlargeEruptions de la Soufrière - ash covers the island - photos St. Vincent and the Grenadines and R.Robertson (pluricentimetric slag samples on the Rabacca river area more than 7 km from the volcano) - one click to enlarge
Eruptions de la Soufrière - ash covers the island - photos St. Vincent and the Grenadines and R.Robertson (pluricentimetric slag samples on the Rabacca river area more than 7 km from the volcano) - one click to enlarge

Eruptions de la Soufrière - ash covers the island - photos St. Vincent and the Grenadines and R.Robertson (pluricentimetric slag samples on the Rabacca river area more than 7 km from the volcano) - one click to enlarge

Soufrière - How to protect yourself from the ashes? Wear respiratory and eye protection, stay indoors, clean and preserve the water reserves - Doc. IAVCEI / WHO / IVHHN

Soufrière - How to protect yourself from the ashes? Wear respiratory and eye protection, stay indoors, clean and preserve the water reserves - Doc. IAVCEI / WHO / IVHHN

At the seismicity level, following the gradual decline of the quasi-continuous seismic tremor at La Soufrière, St Vincent, the seismic network began to record a tremor in bands from around 3:30 am on April 10.
The band tremor is a seismic signal that indicates that the fluid (magma and gas) is approaching the surface
Each episode of tremor lasted 20 to 30 minutes, with intervals of one to three hours between them. The episodes appeared to coincide with periods of increased ventilation or explosive activity.
The seismic tremor background level between episodes continued to decrease.

 

Sources UWI-SRC & NEMO SVG

Piton de La Fournaise -10.04.2021 - the eruptive fissure - photo OVPF / SAG

Piton de La Fournaise -10.04.2021 - the eruptive fissure - photo OVPF / SAG

At Piton de La Fournaise, a reconnaissance flight took place in the morning of Saturday, making it possible to determine that the situation was stable, after a drop in intensity recorded on Friday evening around 9 p.m. "The flow is very slow, but the eruption remains stable for the time being" details Aline Peltier, director of the OVPF.

"During the overflight, around 8.40 am local time, the activity focused on two main eruptive vents in which several regimes of lava fountains were observed" underlines the OVPF.

The eruptive activity continues on a main mouth and a secondary mouth. The front of the flow was located this morning at 7am at an altitude of 1750m upstream of the Grandes Pentes broken.

 

Sources : OVPF & Local media / Imazpress - Réunion 1 °

Piton de La Fournaise - 04.11.2021 / 09:47 - The eruptive fissure is located downstream from the Château Fort crater on the southern flank of the volcano inside the Enclosure (Copyright Webcam OVPF-IRT)

Piton de La Fournaise - 04.11.2021 / 09:47 - The eruptive fissure is located downstream from the Château Fort crater on the southern flank of the volcano inside the Enclosure (Copyright Webcam OVPF-IRT)

Piton de La Fournaise - The eruptive activity continues on a main mouth and a secondary mouth. - OVPF photo

Piton de La Fournaise - The eruptive activity continues on a main mouth and a secondary mouth. - OVPF photo

In the Reykjanes Peninsula, according to forecasts by the Icelandic Meteorological Office, gas pollution will reach settlements within the next 24 hours.

Tonight there will be pollution in the northern part of the Reykjanes peninsula and in the capital region. In the morning there will probably be gas pollution over Vatnsleysuströnd, but in the afternoon over the area from Vogar to Reykjanesbær and west to Höfn, and then towards Grindavík due to changes in wind direction .
Tonight there will be five to ten meters per second in the southeast and south of eruption sites and snow with sections and freezing temperatures.

 

Sources: RUV, mbls, IMO

Geldingadalur - 04.10.2021 07:13 - RUV webcam

Geldingadalur - 04.10.2021 07:13 - RUV webcam

Meradalur - frequentation of this eruptive site 10.04.2021 - photo via SkyAlert

Meradalur - frequentation of this eruptive site 10.04.2021 - photo via SkyAlert

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
Soufrière de St. Vincent - primary explosion from 8:41 am / 09.04.2021 - photo R.Robertson around 10 am

Soufrière de St. Vincent - primary explosion from 8:41 am / 09.04.2021 - photo R.Robertson around 10 am

After the initial explosion of La Soufrière in St. Vincent at 8:41 a.m. on April 9, 2021, which was accompanied by a plume of ash and gas with an estimated height of 10,000 meters (Dr. Robertson), the seismicity rose again around 11:30 a.m., as a seismic swarm that ended at 2:40 p.m.

At 2:58 p.m .: a second explosion occurred, accompanied by a vertical plume of gas and ash about 4 km high.

It continues nourished by successive impulses.

Tremor has been recorded continuously since 3 p.m., the most important signals accompanying the most important phases of ash emissions, charged with lightning.

Soufrière de St. Vincent - 2nd explosion from 2:58 p.m. / 09.04.2021 - photo R.Robertson

Soufrière de St. Vincent - 2nd explosion from 2:58 p.m. / 09.04.2021 - photo R.Robertson

Soufriere de St. Vincent - lightning streaks through ash plume - photo 09.04.2021 / UWI-SRC

Soufriere de St. Vincent - lightning streaks through ash plume - photo 09.04.2021 / UWI-SRC

A plume of sulfur dioxide was spotted by Sentinel 5P Tropomi at 5:06 p.m. - 5:07 p.m. about 2 kilotons are moving east of the volcano (Simon Carn).

Soufrière de St. Vincent - traces of SO2 / image Sentinel 5P Tropomi from 09.04.2021 / 5:06 p.m. - 5:07 p.m. via S. Carn

Soufrière de St. Vincent - traces of SO2 / image Sentinel 5P Tropomi from 09.04.2021 / 5:06 p.m. - 5:07 p.m. via S. Carn

A third explosion occurred from 6.35 p.m.,

 

Sources: UWI-SRC, NEMO SVG, The University of the West Indoes - Media release 09,04,2021

Soufrière of St. Vincent - 3rd explosion in progress from 6.35 p.m. - photo UWI-SRC

Soufrière of St. Vincent - 3rd explosion in progress from 6.35 p.m. - photo UWI-SRC

Since 2:57 p.m. local time (10:57 a.m. UTC), a seismic crisis has been recorded on the instruments of the Piton de la Fournaise Volcanological Observatory. This seismic crisis is accompanied by rapid deformation. This indicates that the magma is leaving the magma reservoir and is spreading towards the surface.

Between 2:47 p.m. and 5:45 p.m. (local time), more than 700 superficial volcano-tectonic earthquakes were recorded by the Piton de la Fournaise Volcanological Observatory. The source of the deformation and the seismicity show a propagation of magma under the southern flank, with events located less than 1 km from the rampart of the Enclos Fouqué.

The volcanic tremor synonymous with the arrival of magma near the surface has been recorded since 19:00 local time. According to OVPF records, the source of this tremor is located on the southern flank of the volcano inside the Enclosure.

No visual confirmation of the start of an eruption could be made on webcams yet due to bad weather conditions

However, the presence of a tremor shows the emission of hot and incandescent gases on the surface, and the possibility of lava emission in the very short term.

Piton de la Fournaise - first images provided by the Piton de Bert webcam on 09.04.2021 at 15:35 UT and 20:35 UT - Doc. OVPF - one click to enlargePiton de la Fournaise - first images provided by the Piton de Bert webcam on 09.04.2021 at 15:35 UT and 20:35 UT - Doc. OVPF - one click to enlarge

Piton de la Fournaise - first images provided by the Piton de Bert webcam on 09.04.2021 at 15:35 UT and 20:35 UT - Doc. OVPF - one click to enlarge

Piton de la Fournaise - seismogram of 09.04.2021 / 11h-11:20 am

Piton de la Fournaise - seismogram of 09.04.2021 / 11h-11:20 am

Piton de La Fournaise - overview of 04.10.2021 - Imazpress photo

Piton de La Fournaise - overview of 04.10.2021 - Imazpress photo

A first flight on April 10, commented by Nicolas Villeneuve, provides indications: "The eruption is quite weak in intensity. The projections do not exceed 20 meters high. The flow which has advanced 1.5 km spreads out. 150 meters. She has difficulty moving forward since she is now on a plateau. Two arms have formed at first. The first stopped quite quickly. The second is well fed upstream, but it is cooling down fast enough and for the moment the flow is frozen. "

The OVPF has just reported that: "The activity is currently focused on two main eruptive vents. The upstream part of the crack is no longer active"

The recommended alert level: Alert 2-2, as of this Friday April 9 at 7:00 p.m. Public access to the Fouqué enclosure, from the Pas de Bellecombe trail or from any other trail, as well as the aircraft in the volcano area are banned until further notice.

 

Source: OVPF & Prefecture of Reunion - Imazpress

Piton de La Fournaise - flyover of 04.10.2021: a first arm of lava flow hit a cone, the second is powered, but is frozen - Imazpress photos - one click to enlarge
Piton de La Fournaise - flyover of 04.10.2021: a first arm of lava flow hit a cone, the second is powered, but is frozen - Imazpress photos - one click to enlarge

Piton de La Fournaise - flyover of 04.10.2021: a first arm of lava flow hit a cone, the second is powered, but is frozen - Imazpress photos - one click to enlarge

Piton de La Fournaise eruption - 04.10.2021 - Imazpress video

Signs of change have appeared in the Reykjanes Peninsula, with the new fissures opening one on Easter and April 5. However, the changes are very small, and the portents before the cracks open are not detectable.

There are indications that the magma is shallow in the area south of Geldingadalur and northeast of the eruptions and it cannot be excluded that further eruptions may open in the coming days or weeks. Opening a new eruptive fissure without visible warning could pose an acute danger to people. It is believed that the area covered by this danger is where the magma reached closest to the surface or the southwestern part of Geldingadalur and northeast of Litla-Hrúti.

The steep, elevated edges of lava fields at eruption sites can be unstable. Large chunks of glowing lava can escape without warning, which can create a lot of danger. Likewise, magma can gush out under the lava rim and this magma can travel very fast.

Reykjanes Peninsula - eruptive sites - The map defines the area where people may be in acute danger due to sudden events that may occur at the eruption sites. In the danger zone, there is the greatest risk of opening more eruption cracks without warning, and this can be accompanied by a sudden and rapid lava flow that is difficult to avoid. Apart from this area, there are also other dangers associated with lava flow and gas build-up. The map shows a draft of a new hiking trail east of the danger zone. - one click to enlarge

Reykjanes Peninsula - eruptive sites - The map defines the area where people may be in acute danger due to sudden events that may occur at the eruption sites. In the danger zone, there is the greatest risk of opening more eruption cracks without warning, and this can be accompanied by a sudden and rapid lava flow that is difficult to avoid. Apart from this area, there are also other dangers associated with lava flow and gas build-up. The map shows a draft of a new hiking trail east of the danger zone. - one click to enlarge

The greatest seismic activity over the past two weeks is north of the magma chamber in the Keilir area. Just south of Keilir, near Litla-Hrút, shallow earthquakes are detected and this activity is closely monitored. Shallow earthquakes can be a sign that magma is pointing to the surface. It is therefore not excluded that the magma reaches the surface north of the magma chamber which reaches Keilir.

It is likely that with increased lava flow, gas pollution will increase
Preliminary measurements indicate that the lava flow increased further with the opening of the last eruption cracks, but more precise measurements are expected today. Lava flows from the three cracks and descends into Meradali and Geldingadalur.

 

Source: IMO -  09,04,2021 8:30 p.m.

Reykjanes Peninsula - the eruptive sites on 04.09.2021 / 06:08 - - webcam RUV Meradalur

Reykjanes Peninsula - the eruptive sites on 04.09.2021 / 06:08 - - webcam RUV Meradalur

Last minute : a fourth fissure has opened between fissures 2 and 3, and is pouring its lava towards Geldingadalur .   

Reykjanes Peninsula- 10.04.2021 Geldingadalgos - opening of a 4th eruptive fissure.

Reykjanes Peninsula- 10.04.2021 Geldingadalgos - opening of a 4th eruptive fissure.

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
St. Vincent -  la Soufrière enters an explosive eruptive phase this April 9 at 8:41 am local - photos R. Robertson / UWI
St. Vincent -  la Soufrière enters an explosive eruptive phase this April 9 at 8:41 am local - photos R. Robertson / UWI

St. Vincent -  la Soufrière enters an explosive eruptive phase this April 9 at 8:41 am local - photos R. Robertson / UWI

In St. Vincent, the Belmont observatory confirms the start of an explosive eruptive phase in La Soufrière on April 9, 2021 at 8:41 am, accompanied by an ash plume at more than 8,000 meters. The ashes of the plume drift towards the east of the island.

The explosion follows the current effusive eruption and the rapid height expansion of its dome on April 8, with increased seismicity, justifying the order to evacuate the red zone.

Ash fallout is recorded on the flanks of the volcano and the communities of Chateaubelair and Petite Bordel, as well as at the Argyle International Airport, and the general and immediate evacuation of the red zone is ordered.

 

This is the first explosive eruption at La Soufrière since 1979, although an effusive eruptive phase has been underway at the top since the end of December 2021.

A change in the character of a rash like this is not uncommon. Viscous andesitic lava like that from the new dome that had formed at La Soufrière can trap gases as new magma rises below, creating pressure that can lead to a more explosive style of eruption.

 

Sources: UWI-SRC & NEMO SVG

Soufrière de St. Vincent - 09.04.2021- ash concentration in the plume to the east of SV - Doc. NEMO

Soufrière de St. Vincent - 09.04.2021- ash concentration in the plume to the east of SV - Doc. NEMO

La Soufriere Eruption 9th.April.2021 currently Erupting on the most Northern End of St Vincent.. La Soufriere Volcano. 9th April2021 - Adventure Island SV video

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Publié le par Bernard Duyck
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Soufrière de St. Vincent - 08.04.2021 / 18h26  - Doc. UWI-SRC

Soufrière de St. Vincent - 08.04.2021 / 18h26  - Doc. UWI-SRC

Seismic activity at La Soufrière, St Vincent changed significantly today when the seismic station closest to the summit began recording low level earthquakes on April 8.

Six separate episodes, or bands, of tremors starting at 3 a.m. were recorded with intervals of about two and a half hours between them. The quake episodes slowly increased in magnitude.A tremor is a continuous seismic signal usually associated with the movement of magma toward the surface.

The seismic network also recorded five long-lived earthquakes during the second and fourth quake bands. Long-lived earthquakes are also generally associated with the movement of magma.

There were also two brief swarms of small volcano-tectonic (VT) earthquakes, both occurring between bands of quakes. These were located at depths of up to 5 kilometers below the summit of Soufrière, which is consistent with the depths of the two VT swarms on March 23-26 and April 5.

High and continuous periods of gas evolution from the top of the volcano, coinciding with the tremor bands were observed. Sometimes there was a well-defined plume.

Visual observations from Belmont Observatory in the early evening indicate that the height of the dome has increased significantly during the day. The glow of the dome was visible from Belmont.

The volcano has entered a period of heightened activity indicating a new batch of magma near or approaching the surface. The possibility for the activity to go into an explosive phase has increased significantly. Based on current data, it is not possible to say exactly what the timescale would be.
NEMO Saint Vincent and the Grenadines

Soufrière de St. Vincent - 08.04.2021 / 21:57 - the incandescence is visible from Chateaubelair - Doc. UWI-SRC

Soufrière de St. Vincent - 08.04.2021 / 21:57 - the incandescence is visible from Chateaubelair - Doc. UWI-SRC

Prime Minister Dr Ralph Gonsalves has issued an evacuation order with immediate effect.

The safety zones are North Union to Kingstown on the windward side of the island, Barouallie to Kingstown on the leeward side and the Grenadine Islands.

During the night of April 8-9, for residents of Fancy and above the river, evacuations began.

Sources : UWI-SRC & NEMO SVG

Map defining the evacuation zones - The earthquakes of 08.04 were felt in Fancy and Sandy bay - Doc. UWI-SRC

Map defining the evacuation zones - The earthquakes of 08.04 were felt in Fancy and Sandy bay - Doc. UWI-SRC

Soufriere de St. Vincent - thermal anomaly (selom Mirova between VRP28 and 52 MW on 04/08) - Sentinel-2 band image 12,11,8A of 04/08/2021 / 2:37 p.m. via Mounts project

Soufriere de St. Vincent - thermal anomaly (selom Mirova between VRP28 and 52 MW on 04/08) - Sentinel-2 band image 12,11,8A of 04/08/2021 / 2:37 p.m. via Mounts project

La Soufriere Eruption 8th April- 2021. Climbing into the crater of an Eruption. - vidéo Island Vibes / https://youtu.be/XDMxTTS0G3U

Seismicity and inflation under the Piton de la Fournaise continue.

For the day of April 8, 2021, 48 earthquakes were recorded under the summit area. The GPS of the summit zone and in the far field record an ingflation, witness of the pressurization of a superficial and deep source

This recharging process observed since March 13, 2021 can last several days to several weeks.

 

Source: OVPF

Piton de La Fournaise - Illustration of the deformation between 09.02.2021 and 09.04.2021 -. The baselines (variation of distance between two GPS receivers) crossing the Piton de la Fournaise building, at the top (top), the base of the terminal cone (in the middle) and in the far field (bottom) are shown here. ) (see location on the associated maps). An increase is synonymous with elongation and therefore swelling of the volcano; conversely, a decrease is synonymous with contraction and therefore deflation of the volcano. Any periods colored in light pink correspond to eruptions. - OVPF

Piton de La Fournaise - Illustration of the deformation between 09.02.2021 and 09.04.2021 -. The baselines (variation of distance between two GPS receivers) crossing the Piton de la Fournaise building, at the top (top), the base of the terminal cone (in the middle) and in the far field (bottom) are shown here. ) (see location on the associated maps). An increase is synonymous with elongation and therefore swelling of the volcano; conversely, a decrease is synonymous with contraction and therefore deflation of the volcano. Any periods colored in light pink correspond to eruptions. - OVPF

Piton de La Fournaise - increase in the number of earthquakes since March 13, 2021 - Doc. OVPF

Piton de La Fournaise - increase in the number of earthquakes since March 13, 2021 - Doc. OVPF

In Sinabung, in activity level 3 / siaga, the PVMBG provides information for April 8, 2021:

- 3 eruption earthquakes, with an amplitude of 22 to 33 mm, and the duration of the earthquake was 133 to 185 seconds.
- 1 earthquake related to a pyroclastic flow, with an amplitude of 120 mm and an earthquake duration of 216 seconds.
- 92 collapse / avalanche earthquakes, with an amplitude of 3 to 120 mm and a duration of 20 to 190 seconds of the earthquake.
- 8 blast / emission earthquakes, with an amplitude of 4 to 19 mm and the earthquake lasted 20 to 70 seconds.
- 13 low frequency earthquakes with an amplitude of 2 to 20 mm, and the duration of the earthquake was 10 to 34 seconds.
- 32 hybrid / multiphase earthquakes with an amplitude of 2 to 12 mm, the S-P was not observed and the earthquake lasted 5 to 20 seconds.

 

Seismicity has not changed much since early March.

 

Sources: PVMBG, Magma indonesia

Sinabung by Tiga Kicat- 08.04.2021 / 19:16 WIB - photo Sadrah Peranginangin

Sinabung by Tiga Kicat- 08.04.2021 / 19:16 WIB - photo Sadrah Peranginangin

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Pacaya - Monitoring of the advance of the lava flow, marked by a slight degassing - photo Conred 07.04.2021

Pacaya - Monitoring of the advance of the lava flow, marked by a slight degassing - photo Conred 07.04.2021

At Pacaya, the eruptive activity remains within the explosive and effusive standards of the previous days, with an extension of the length of the flow which advances by 5 meters per hour, and has a width of 300 meters.

 

Source: Conred

Pacaya - explosive and effusive activity of 07.04.2021 - Conred photos
Pacaya - explosive and effusive activity of 07.04.2021 - Conred photos

Pacaya - explosive and effusive activity of 07.04.2021 - Conred photos

At Merapi, the BPPTKG reports for the day of April 7:

- an earthquake related to a pyroclastic flow, recorded on a seismogram with an amplitude of 40 mm and lasting 114 seconds.

- 134 collapse / avalanche earthquakes, amplitude between 3 and 75 mm, lasting 10 to 117 sec.

- 2 hybrid multiphase earthquakes.

 

The activity level remains at 3 / siaga.

 

Source: BPPTKG

Merapi - pyroclastic flow of 08.04.2021 / 10:39 WIB - photo Babadan2 - G. Merapi - BadanGeology

Merapi - pyroclastic flow of 08.04.2021 / 10:39 WIB - photo Babadan2 - G. Merapi - BadanGeology

Merapi - seismicity from 04/07/2021 / midnight to midnight. - Doc. BPPTKG

Merapi - seismicity from 04/07/2021 / midnight to midnight. - Doc. BPPTKG

Reykjanes Peninsula - the 3 eruptive fissures, with their respective cones - webcam RUV / 07.04.2021 / 06:15

Reykjanes Peninsula - the 3 eruptive fissures, with their respective cones - webcam RUV / 07.04.2021 / 06:15

Reykjanes Peninsula - the 3 eruptive fissures, with their respective cones, and evolution of the lava field  - webcam RUV / 07.04.2021 / 15:03

Reykjanes Peninsula - the 3 eruptive fissures, with their respective cones, and evolution of the lava field - webcam RUV / 07.04.2021 / 15:03

In the Reykjanes Peninsula, the eruption continues; The flow in the main channel was measured from video at a flow speed of 7.7 m./s., or 28 km / h.

The photos taken on April 7 show that the new (central) fissure emits on both sides, and in the process swallowed the webcam, and that the lava fields have merged : a continuous lava field and three eruptive sites, which belong to the to the same eruptive fissure. This extends from Natthaga north-east to Kellir, above the magma corridor drawn since February.

Feeding lava tube - Iceland Editions

 

Sources: IMO, RUV, mbls, Visir.

Reykjanes Peninsula - A single and same lava field unites the three eruptive sites - photo IMO / Almannavarnir - Björn Oddsson; the diagram leaves its central part in hatched, the cartography was still to be carried out. - one click to enlarge
Reykjanes Peninsula - A single and same lava field unites the three eruptive sites - photo IMO / Almannavarnir - Björn Oddsson; the diagram leaves its central part in hatched, the cartography was still to be carried out. - one click to enlarge

Reykjanes Peninsula - A single and same lava field unites the three eruptive sites - photo IMO / Almannavarnir - Björn Oddsson; the diagram leaves its central part in hatched, the cartography was still to be carried out. - one click to enlarge

The New Fissure and Its Long Lava Flow - RVK newcast

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A new study of lava was carried out in the Reykjanes Peninsula today, April 6, using vertical aircraft photogrammetry.

The results indicate that the lava flow is very weak in Geldingadalir and that the average flow since yesterday in the new crack is 4-5 m3 / s. The total flow is estimated at 5-6 m3 / s. Apparently, the increase seen yesterday was temporary. The intensity of the rash is therefore similar to what it was in the days before the new crack opened.

Reykjanes Peninsula - surface parameters, quantities of lava emitted, emission velocity ratio and lava composition - doc. Univ. Iceland 04/06/2021 / 1:18 p.m.

Reykjanes Peninsula - surface parameters, quantities of lava emitted, emission velocity ratio and lava composition - doc. Univ. Iceland 04/06/2021 / 1:18 p.m.

A third crack opened at midnight between the two eruptive sites in Reykjanes, according to Einar Hjörleifsson, a nature conservation expert at the Icelandic Meteorological Office. The new crack opened directly in front of the web camera, 420 meters north of the spring in Geldingadalur.

Rescue teams saw a landslide in the area yesterday, which was about 150 m long and about 1 meter deep, likely location of the new activity.
Lava flows from the new fissure towards Geldingadalur.

Geldingadalur - 3rd crack zone (left), with flow towards Gelingadalur - RUV webcam 04/07/2021 / 00h52

Geldingadalur - 3rd crack zone (left), with flow towards Gelingadalur - RUV webcam 04/07/2021 / 00h52

Reykjanes peninsula - new crack opened on 04/06/2021 around midnight between the 2 eruptive sites - photo frettabladid.is

Reykjanes peninsula - new crack opened on 04/06/2021 around midnight between the 2 eruptive sites - photo frettabladid.is

Davíð Már Stefánsson, Information Officer for Landsbjörg, announced earlier today that it has been decided to expand the danger zone, as there are now eruption sites in two places and cracks between both.
The area is closed until a new assessment.

 

Sources: IMO, RUV, mbls, Visir, Frettabladid

Reykjanes Peninsula - Possible lava flow path if the eruption lasts longer (4-5 months to overflow from Meradalir according to Prof. Magnús Tumi Guðmundsson) - Doc. via Oroapuls April 2021

Reykjanes Peninsula - Possible lava flow path if the eruption lasts longer (4-5 months to overflow from Meradalir according to Prof. Magnús Tumi Guðmundsson) - Doc. via Oroapuls April 2021

Continuous high activity in Pacaya, with an effusive predominance; the western lava flow continues its course, 3,000 meters long on April 6 around 3 pm, in the vicinity of the communities of El Patronicio and El Rodeo. Its direction varies according to the topography; it has formed several ramifications. The flows cause fires in vegetation and crops, the destruction of buildings and the cutting of the paths. avalanches of boulders mark the flow front, as well as a degassing charged with sulfur dioxide dangerous for the respiratory system.

Pacaya - RSAM from 31.03 to 06.04.2021 - Doc. Insivumeh

Pacaya - RSAM from 31.03 to 06.04.2021 - Doc. Insivumeh

The few explosions at Mackenney crater expel incandescent materials over 100 meters and generate ash plumes reaching 3,700 meters asl., and constant falls on communities located to the south and southeast of the volcano.

The observed variations in seismic parameters are consistent with the periods of greatest activity at the Mackenney crater and the cracks that feed the flows.

 

Source: Insivumeh - 06.04.2021 / 3 p.m. local

Veniaminof - photo archives AVO / Jacob ben David 11.03.2021

Veniaminof - photo archives AVO / Jacob ben David 11.03.2021

Likely low level ash emissions were observed in web camera views from the summit of Veniaminof. Seismic activity remains high. Due to the renewed activity, AVO is raising the Aviation Color Code to ORANGE and the Volcano Alert Level to Watch. The Alaska Volcano Observatory continues to monitor Veniaminof with a local seismic network, remote infrasound and lightning networks, as well as satellite and webcam images.

Eruptive activity at Veniaminof typically consists of minor ash emissions, lava fountains, and lava flows from the small cone in the summit caldera.

Source: AVO

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 Meradalur - the lava flow near the camp on 04.05.2021 - photo Björgunarsveitin Þorbjörn

Meradalur - the lava flow near the camp on 04.05.2021 - photo Björgunarsveitin Þorbjörn

Meradalur - lava flow and delta on 04.05.2021 - photo Visir / Wilhem

Meradalur - lava flow and delta on 04.05.2021 - photo Visir / Wilhem

Some additional information to that of April 5 afternoon (see article: http://www.earth-of-fire.com/2021/04/opening-of-2-new-cracks-in-the-reykjanes-peninsula.html )

The fissure eruption that opened on April 5 around 12 p.m. in Geldingadalur is about 200 meters from the tent camp that the Þorbjörn rescue team has occupied in recent weeks. Members of the Þorbjörn team quickly went to the scene to take the tents and equipment to a safe place.

The lava emitted is very fluid and helped by the difference in level, the flow has reached the valley where it forms a small delta.

Meradalur - rapid evacuation of the camp - photo 05.04.2021 Björgunarsveitin Þorbjörn

Meradalur - rapid evacuation of the camp - photo 05.04.2021 Björgunarsveitin Þorbjörn

Meradalur - rapid evacuation of the camp - photo 05.04.2021 Björgunarsveitin Þorbjörn

Meradalur - rapid evacuation of the camp - photo 05.04.2021 Björgunarsveitin Þorbjörn

Reykjanes Peninsula - Landscape location of active sites - photos and captions / Iceland 360 ° VR - one click to enlarge

Reykjanes Peninsula - Landscape location of active sites - photos and captions / Iceland 360 ° VR - one click to enlarge

Measurements were made on the lava on April 5, using aerial photographs. No reliable estimate of the lava flow was obtained in the old craters, but the new fissure produced 7 cubic meters per second. The total flow (Geldingadalir + new crack) is now estimated at 10 cubic meters per second. The eruption therefore got bigger.

Reykjanes Peninsula - parameters of the eruption as of 05.04.2021 Doc. Iceland University

Reykjanes Peninsula - parameters of the eruption as of 05.04.2021 Doc. Iceland University

The area is considered dangerous, due to various factors: the possible opening without warning of new fractures, the constant pollution by volcanic gases, the difficult conditions encountered during the trail, to which are added the weather conditions (intense cold - 9 ° C, strong wind, sleet and / or snow). It remains closed for now, and we must focus on the webcams.

 

Sources: IMO, RUV, mbls, Visir, Almannavarnadeild ríkislögreglustjóra

Meradalur - lava flow and delta during the night and on 04.06.2021 / 06:38 - (new) webcam RUV - one click to enlarge
Meradalur - lava flow and delta during the night and on 04.06.2021 / 06:38 - (new) webcam RUV - one click to enlarge

Meradalur - lava flow and delta during the night and on 04.06.2021 / 06:38 - (new) webcam RUV - one click to enlarge

At the Soufrière of St. Vincent on April 5, a new swarm of volcano-tectonic (VT) earthquakes began at 6:38 am. The number and magnitude of these earthquakes increased until about 8:30 a.m., after which they continued at a fairly steady rate.

This swarm of VT earthquakes was located at a depth of about 6 km below the summit of the Soufrière. This is slightly deeper than the VT seismic activities recorded between March 22 and 25, which were located at depths of 3 to 5 km below the summit.

The largest VT earthquake occurred at 9:20 a.m. with a magnitude of 3.5 and was felt by residents living near the volcano. Other VT earthquakes may also have been felt.

The alert level remains at Orange.

NEMO also encourages residents, especially people living in communities near the volcano, to prepare in case it becomes necessary to evacuate at short notice.

 

Sources: UWI-SRC & Nemo

Soufriere de St. Vincent - the new dome surrounding the old one on 04/01/2021 - photo UWI-SRC, / Prof Robertson. - one click to enlarge

Soufriere de St. Vincent - the new dome surrounding the old one on 04/01/2021 - photo UWI-SRC, / Prof Robertson. - one click to enlarge

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An additional new crack opened around 12:00 p.m. on April 5, 2021 near the initial eruption site in Geldingadalur.

Early estimates of the crack length are approx. 200 meters, and the middle of the fissure is about 1 kilometer northeast of the Geldingadalir eruption site. Lava from the new fissure flows towards the valleys of Meradalir, east of the new fissure.

Icelandic Coast Guard helicopters are at the new eruption site to ensure the area is evacuated. An aerial plain with scientists is on their way to the crack to more accurately assess the location and size of the new crack.

The evacuation of responders in and around Geldingadalur was a success, according to Gunnar Schram, police chief in Suðurnes. Hundreds of people were in the area when the crack opened.

Due to the lack of ash and tephra emission into the atmosphere, the aviation color code of Keflavik Airport remains orange as there is no imminent danger to aviation.

Sources: IMO & Police in Suðurnes

Reykjanes Peninsula - the two eruptive sites on 05.04.2021 in the early afternoon - RUV webcam - click on all the photos to enlarge

Reykjanes Peninsula - the two eruptive sites on 05.04.2021 in the early afternoon - RUV webcam - click on all the photos to enlarge

New crack and its rampart of spatters - 05.04.2021 -photo Almannavarnadeild ríkislögreglustjóra

New crack and its rampart of spatters - 05.04.2021 -photo Almannavarnadeild ríkislögreglustjóra

Update:

The eruptive centers are located about 700 meters from each other; the new one is northeast of the volcanic craters of Geldingadalur. The cracks are in total about 100 to 200 meters long. The lava from the fissures is fluid and flows in a long, narrow lava river east of Merardalur where a lava field is already starting to form there.

The two eruptive sites - at the top of the porthole, Geldingadalsgos, and in the foreground, the fissure towards Meradalur - photo 05.04.2021 / Coast Guard's helicopter squad

The two eruptive sites - at the top of the porthole, Geldingadalsgos, and in the foreground, the fissure towards Meradalur - photo 05.04.2021 / Coast Guard's helicopter squad

Meradalur - the crack, on the right and the flow towards Merardalur - photo Almannavarnadeild ríkislögreglustjóra

Meradalur - the crack, on the right and the flow towards Merardalur - photo Almannavarnadeild ríkislögreglustjóra

Meradalur - new lava field in formation - photo K. Jonsdottir 05.04.2021 (the cars on the left give the ladder)

Meradalur - new lava field in formation - photo K. Jonsdottir 05.04.2021 (the cars on the left give the ladder)

At 4:39 p.m., RUV communicated that a second crack opened today and is much smaller in shape than the first which opened at noon, probably several tens of meters, according to Salóme Jórunn Bernharðsdóttir, conservation specialist nature at the Icelandic meteorological office.

The RÚV webcam focuses on the new eruption cracks, but the mbl.is webcam is still in place, focusing on the eruption of Geldingadalur. And it is clear that the eruption slowed down a lot there, as the new cracks are probably lined up on the same feed channel.

Páll Einarsson, a geophysicist, had noticed that around ten o'clock there were changes in the turbulence of the eruption at the cone level in Geldingadalur.

To be continued ...

 

Sources: IMO, RUV, mbls, Almannavarnadeild ríkislögreglustjóra

Meradalur - the 2 cracks and the rampart spatter - photo 05.04.2021 / Almannavarnadeild ríkislögreglustjóra

Meradalur - the 2 cracks and the rampart spatter - photo 05.04.2021 / Almannavarnadeild ríkislögreglustjóra

The two eruptive sites, seen at 180 ° - photos IMO & Almannavarnadeild ríkislögreglustjóra
The two eruptive sites, seen at 180 ° - photos IMO & Almannavarnadeild ríkislögreglustjóra

The two eruptive sites, seen at 180 ° - photos IMO & Almannavarnadeild ríkislögreglustjóra

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In Sakurajima, the activity of the Minamidake crater remains important.

Note the explosions of April 4 at 11:35 p.m. local, accompanied by a plume of ash 2,000 meters above the crater, drifting to the southeast.

Likewise, an explosion took place on April 5 at 6:41 am local time, accompanied by a plume 3,000 meters above the crater.

The JMA reports, for each of them, large bombs which disperse at the level of the 6th station, around 800-1.100 meters from the summit crater Minamidake

 

Sources: JMA & VAAC Tokyo

Sakurajima - 04.04.2021 / 23:42 JST - Doc. JMA

Sakurajima - 04.04.2021 / 23:42 JST - Doc. JMA

Sakurajima - 05.04.2021 / 06:48 JST - Doc. JMA

Sakurajima - 05.04.2021 / 06:48 JST - Doc. JMA

Sakurajima - 04.05.2021 / around 06:41 JST

In Guatemala, the Pacaya maintains a high level of activity, with plumes of ash and gas at 3,000 meters asl. And sporadic dispersions of ash over a southern sector.

On the southwest flank, the active lava flow currently measures 2,850 meters; it presents ramifications and incandescent avalanches at the flow fronts, affecting the vegetation.

A reconnaissance made using a drone equipped with a thermal camera made it possible to determine the progress of the flows and those of the hot spots.

 

Sources: Insivumeh, Conred, Sentinel-2, Mirova

Pacaya - image Sentinel-2 bands 12,11, 5 of 04.04.2021 - doc. Insivumeh

Pacaya - image Sentinel-2 bands 12,11, 5 of 04.04.2021 - doc. Insivumeh

Pacaya - degassing lava flow / a length of 2850 m. - photo Conred

Pacaya - degassing lava flow / a length of 2850 m. - photo Conred

Pacaya - drone / camerathermic measurements of hot spots and extent of flows - Insivumeh images - one click to enlarge
Pacaya - drone / camerathermic measurements of hot spots and extent of flows - Insivumeh images - one click to enlargePacaya - drone / camerathermic measurements of hot spots and extent of flows - Insivumeh images - one click to enlarge

Pacaya - drone / camerathermic measurements of hot spots and extent of flows - Insivumeh images - one click to enlarge

Regarding the eruption in Geldingadalur, IMO mentions its continuation, with a stable flow ratio. The sulfur gas fumes remain dangerous.

During the day of yesterday, two collapses of the edge of the southern crater took place; the blocks of lava were carried by the flows towards the lava field, which fills more and more the valley.

The frost is permanent on the relief and winter precipitation expected ... but these weather conditions should not slow down the flow of the curious. It is recommended not to bring children and animals near the eruptive site, due to the presence of toxic gases.

 

Sources: IMO, RUV, mbls

Geldingadalgos - modifications to the eruptive site between 01 and 04/03/2021 (drainage of the lava basin to the left of the cones and straying of blocks in the flows, depending on the position of the yellow and orange dots) - photo Eldfjallafræði og náttúruvárhópur Háskóla Íslands - one click to enlarge

Geldingadalgos - modifications to the eruptive site between 01 and 04/03/2021 (drainage of the lava basin to the left of the cones and straying of blocks in the flows, depending on the position of the yellow and orange dots) - photo Eldfjallafræði og náttúruvárhópur Háskóla Íslands - one click to enlarge

Geldingadalgos - 04.04.2021 / 09:15 - mbls webcam - one click to enlarge

Geldingadalgos - 04.04.2021 / 09:15 - mbls webcam - one click to enlarge

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