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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

The growth of the lava dome continues at Sheveluch, with strong fumarole activity; an incandescence of the lava dome, and hot avalanches accompany this process; They are however less important according to Y.Demyanchik / local observatory. Satellite data showed a decreasing thermal anomaly over the volcano.

Aviation color code is Orange - Status is 4 on a scale of 5 / eruption in progress
 

Sources: Kvert, Mirova, Sentinel-2 & Global volcanism Program

Sheveluch - Sentinel-2 bands image 12,11,4 from 04.09.2021 and structural explanations / photo captioned G.V.P.
Sheveluch - Sentinel-2 bands image 12,11,4 from 04.09.2021 and structural explanations / photo captioned G.V.P.

Sheveluch - Sentinel-2 bands image 12,11,4 from 04.09.2021 and structural explanations / photo captioned G.V.P.

I.G. Peru informs us that the activity of Sabancaya remained moderate during the week of 31.08 to 05.09.2021n with an average of 44 daily explosions, accompanied by plumes of gas and ash up to 3,500 m. above the summit.

The number of earthquakes of volcanic origin linked to the circulation of magmatic fluids has decreased, with 584 earthquakes recorded over the week. The VT earthquakes related to the fracturing of rocks of M 3.0 to 3.7, occur mainly in the western and eastern sectors. No significant deformation anomalies.

Mirova detected 10 thermal anomalies, with a max VRP of 24 MW, associated with the presence of a surface lava body in the crater.

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

 

Sources: I.G. Peru and Mirova

Sabancaya - photo of the report from 08.31.2021 to 09.05.2021 - Doc. I.G. Peru

Sabancaya - photo of the report from 08.31.2021 to 09.05.2021 - Doc. I.G. Peru

In the last 24 hours, the Taal volcano network recorded 55 volcanic earthquakes, including 17 volcanic tremor events with durations of 2 to 6 minutes, 36 low frequency volcanic earthquakes, 2 hybrid events and one low background tremor. level which persists since July 7, 2021.

The activity of the main crater was dominated by the rise of hot volcanic fluids in its lake which generated plumes 2,500 meters high which drifted towards the southwest. Sulfur dioxide emissions averaged 6,374 tonnes / day on September 6, 2021.

Alert level 2 (increased unrest) prevails over the Taal volcano.

 

Source: Phivolcs

Taal - sulfur dioxide emissions and nbr. volcanic earthquakes in early September 2021

Taal - sulfur dioxide emissions and nbr. volcanic earthquakes in early September 2021

Taal - gas and steam plume - photo Paleny Paleny 05.09.2021

Taal - gas and steam plume - photo Paleny Paleny 05.09.2021

In Iceland, ENSu representatives were on site in Skaftá today and reviewed conditions in Skælingar and Sveinstindur. The river is very swollen and there are many tides in the tributaries below Skælingar.
The ice cap above the eastern Eystri-Skaftár cauldron has now declined more than 50m and there has been little to no slowdown in this scenario. The flow at Sveinstindur is now over 1350 m³ / s.

 

Source: IMO

Skafta river near the RN1 - screenshot 06.09.2021 / 10:45 am

Skafta river near the RN1 - screenshot 06.09.2021 / 10:45 am

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
. Popocatépetl - activity  04.09.2021 / 1:02 p.m. - WebcamsdeMexico

. Popocatépetl - activity 04.09.2021 / 1:02 p.m. - WebcamsdeMexico

After 3 explosions on September 2 and one on September 3, the activity of Popocatépetl was characterized on September 4 by 96 exhalations accompanied by water vapor and volcanic gases during the last 24 hours, and the recording of 106 minutes low amplitude tremor.

During the last 24 hours, Cenapred reports on September 5, thanks to the monitoring systems of the Popocatepetl volcano, that 79 exhalations accompanied by water vapor and volcanic gases have been identified, and 186 minutes of low amplitude tremor.

The Cenapred recommends not to approach the volcano and especially the crater, because of the danger of falling ballistic fragments and, in the event of heavy rains, to stay away from the bottom of the ravines because of the danger of mud. streams and garbage.

The Popocatépetl volcanic alert remains at Amarillo Fase 2.

 

Sources; Cenapred and webcams from Mexico

Popocatépetl - activity of 05.09.2021 - Doc. Cenapred

Popocatépetl - activity of 05.09.2021 - Doc. Cenapred

In Iceland, the concern concerns three areas: the Reykjanes Peninsula, Vatnajökull, and Askja.

At Fagradalsfjall, the drop in tremor during the day of September 2 was not followed by a remarkable rise; On the morning of September 6, the level of the tremor remains relatively low. It's the longest break since March 19. It cannot be excluded that there is a change in the current eruption.

Fagradalsfjall - Variations of tremor at 06.09.2021 - Doc. Hraun.vedur.is

Fagradalsfjall - Variations of tremor at 06.09.2021 - Doc. Hraun.vedur.is

The National Police Commissioner, in consultation with the Southern Police Commissioner, decreed the level of danger to civil protection due to Skaftárhlaup / Vatnajökull - Grimstvötn.

Runoff from the Eystri-Skaftár cauldron began around noon on September 5, but runoff from the eastern boiler is generally larger than that from the western boiler.

The ice cave is expected to decrease by 60-100m in total. This glacial breakup comes after a jökulhlaup of the western cauldron which is now terminally ill.

The current western cauldron debacle has raised the groundwater level and as a result, the eastern cauldron may spread more in the flooded area than in 2018. In addition to this, considerable precipitation was also observed in the area. these last hours. In addition to the upcoming circular route flooding, the flooding will invade pasture areas and leave large amounts of glacial mud.

Hydrogen sulfide moves with running water when it comes from a glacier. Its concentration is so high that it can damage the mucous membranes of the eyes and respiratory tract. Tourists are therefore strongly advised to stay away from the Skaftár Canal above Skaftárdalur as well as the edges of Skaftárjökull, Tungnárjökull and Síðujökull during the race.

Cracks will form around the cauldrons very quickly, so tourists to Vatnajökull should stay away from these areas, as well as the edges of Skaftárjökull, Tungnárjökull and Síðujökull where running water could rise to the surface.

Jökulhlaup in the Skaftá river - photo Gisli olfsson 05.09.2021

Jökulhlaup in the Skaftá river - photo Gisli olfsson 05.09.2021

GPS measurements at the Eystri-Skaftárkatli cauldron on 05.09.2021 / 19:30 - Doc. Vedur.is

GPS measurements at the Eystri-Skaftárkatli cauldron on 05.09.2021 / 19:30 - Doc. Vedur.is

Real-time monitoring map of the Skaftár area with the flow figures for this morning September 5th. - Doc. IMO

Real-time monitoring map of the Skaftár area with the flow figures for this morning September 5th. - Doc. IMO

According to Freysteinn Sigmundsson, a geophysicist at the Institute of Earth Sciences at the University of Iceland, there are reasons to take the situation around Askja seriously. The ground has risen a few centimeters after subsisting continuously for 40 years and there are indications of a slight increase in seismic activity in the area.

The magma is flowing in the depths of the volcano right now, and now is the time to be more vigilant and exercise increased surveillance of the volcano.

 

Sources: IMO, Visir, mbls

Askja - photo archives Tour guide in Iceland 2019

Askja - photo archives Tour guide in Iceland 2019

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Publié le par Bernard Duyck
Publié dans : #volcanic activity

For the past few weeks, the area of ​​the Fagradalsfjall lava field has not increased and lava has not flowed into new land, says Magnús Tumi Guðmundsson, professor of geophysics at the University of Iceland, speaking about the rash on mbls.

The intermittence of the eruption (see the fluctuations of the tremor) causes more or less long periods without lava flow ... the lava tunnels close.

Fagradalsfjall - tremor on 04.09.2021 / day of rest on 03.09 - Doc. Hraun .vedur.is

Fagradalsfjall - tremor on 04.09.2021 / day of rest on 03.09 - Doc. Hraun .vedur.is

When the eruption resumes, it takes several hours to fill the crater before the lava begins to flow. Lava then flows to the surface in the valleys of Meradalir, Geldingadalir and Nátthagi, but stops before reaching the edge of the lava field. It piles up near the crater.

The lull periods allowed the bottom of the crater to be seen active: The crater basin is about 60 to 70 m deep, and the drain is deeper, below the earth's surface, as before the start of the eruption

 

Sources : mbls & Hraun

Fagradalsfjall eruption - Event # 5 crater - photo Jón Steinar Sæmundsson 27.07.2021 / via mbls - one click to enlarge

Fagradalsfjall eruption - Event # 5 crater - photo Jón Steinar Sæmundsson 27.07.2021 / via mbls - one click to enlarge

Continuous GPS measurements and satellite data from Sentinel-1 (InSAR) show that expansion began in Askja (Dyngjufjöll) in early August 2021. The center of the expansion is at the western end of 'Öskjuvatn near Ólafsgígar near the GPS station which now shows the earth at about 5cm per month.

Askja is an active volcano and there are regular earthquakes, but the last eruption was in Askja in 1961. Regular measurements also showed landslides in the years 1970-1972, but these measurements were discontinued and when regular measurements resumed in 1983, the land had subsided. Since then, a regular landslide of 1 cm per year has been measured so far.

The cause of the current expansion is not entirely clear, but it is believed most likely to be an influx of magma. Volcanoes often show periodic activity as they remain dormant with little activity for years and decades, but in between there are periods of activity with overheating, earthquakes, and geothermal energy. There is no way to predict in advance how such periods of activity will develop, but it is very common for such periods to end without a rash.

The Meteorological Office is closely following the evolution of the situation and will keep you informed of any development of the activity.

 

Source: IMO

Askja - caldera and Öskjuvatn crater lake - photo Oddur Sigurðsson via Icelandic volcanoes

Askja - caldera and Öskjuvatn crater lake - photo Oddur Sigurðsson via Icelandic volcanoes

Askja - The image shows the quasi-vertical deformation in mm for the period August 1 to 21. The InSAR image is obtained from two passes of the Sentinel-1 satellite. Red color indicates increase and blue indicates subsidence (see scale). The area with the highest inflation is northwest Öskjuvatn. The black triangle indicates the location of the nearest GPS station Ólafsgíga (OLAC). - Doc. IMO

Askja - The image shows the quasi-vertical deformation in mm for the period August 1 to 21. The InSAR image is obtained from two passes of the Sentinel-1 satellite. Red color indicates increase and blue indicates subsidence (see scale). The area with the highest inflation is northwest Öskjuvatn. The black triangle indicates the location of the nearest GPS station Ólafsgíga (OLAC). - Doc. IMO

Askja - data from GPS station OLAC: the uprising started between late July and early August (mainly visible in the Up component) and it is still ongoing (September 2, 2021). The dotted red line indicates the estimated rate of climb at ~ 5 cm / month. / Doc. IMO

Askja - data from GPS station OLAC: the uprising started between late July and early August (mainly visible in the Up component) and it is still ongoing (September 2, 2021). The dotted red line indicates the estimated rate of climb at ~ 5 cm / month. / Doc. IMO

Jökulhlaup underway in Skafta. The flood comes from the W-Skaftárcauldron.

The water level in Grímsvötn rose sharply last month and has not been higher since before the eruption of Gjálpar in 1996. About 0.75 cubic kilometers of water accumulated there, according to Eyjólfur Magnússon, scientist at the Institute of Earth Sciences of the University of Iceland. This significant build-up can be attributed to the fact that there has been no ice breakout since 2018.

The flow has been fairly stable at Skaftá near Sveinstindur for the past few hours and now measures around 520 cubic meters per second. It is not unlikely that the runoff has reached its peak if we look at the previous floods from the western cauldron.

When asked if the Icelanders should prepare for a blowout after the next race, Eyjólfur said it was a realistic possibility.

 

Sources: mbls & IMO

The Jökulhlaup in Skaftá may have reached its peak yesterday, but it looks like it will continue in the same way for the next two or three days - photo mbl.is / Jónas Erlendsson - 02.09.2021

The Jökulhlaup in Skaftá may have reached its peak yesterday, but it looks like it will continue in the same way for the next two or three days - photo mbl.is / Jónas Erlendsson - 02.09.2021

The increase in electrical conductivity in the Skaftá River is likely due to steam explosions from the geothermal area under the ice cauldron. Steam explosions occur as the geothermal area adjusts to the decrease in water pressure resulting from the drainage of the cauldron. Explosions increase the amount of dissolved material in flood water, which is detectable downstream as an increase in conductivity in the river. - Doc. IMO

The increase in electrical conductivity in the Skaftá River is likely due to steam explosions from the geothermal area under the ice cauldron. Steam explosions occur as the geothermal area adjusts to the decrease in water pressure resulting from the drainage of the cauldron. Explosions increase the amount of dissolved material in flood water, which is detectable downstream as an increase in conductivity in the river. - Doc. IMO

The lava eruption in the summit crater of the Great Sitkin volcano continued over the past week. Satellite data showed the new lava dome has grown from ~ 90m to ~ 1090m in diameter. Lava filled the crater from the May explosion on August 4 and is now flowing down the sides of the 1974 lava dome. and through the floor of the summit crater. These images show some distortion caused by the oblique illumination angle of the satellite, but capture the changes at the top of the Great Sitkin well.

Gas plumes were visible on satellite images throughout the week, but no explosive activity or ash emissions were detected. Small earthquakes were detected throughout the week, possibly associated with the lava effusion.
There is no indication of how long the lava effusion will continue during the current eruption, and it is possible that explosive activity will occur with little or no warning.

The Great Sitkin volcano is monitored by local seismic and infrasound sensors, satellite data, web cameras, and remote infrasound and lightning networks. The alerts are at Watch / Orange.

 

Source: AVO

Great Sitkin - growing dome between 25.07.2021 and 27.08.2021 - images / Simon Plank (German Aerospace Center, DLR). TerraSAR-X/TanDEM-X © DLR e.V. 2019.  27 août 2021 à 17h56 UTC / via Dietterich Hannah AVO - one click to enlarge

Great Sitkin - growing dome between 25.07.2021 and 27.08.2021 - images / Simon Plank (German Aerospace Center, DLR). TerraSAR-X/TanDEM-X © DLR e.V. 2019. 27 août 2021 à 17h56 UTC / via Dietterich Hannah AVO - one click to enlarge

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
Telica - ash plume - photo Canal12nica 02.09.2021

Telica - ash plume - photo Canal12nica 02.09.2021

Dense and strong ash emissions occurred from the active vent at Telica, Nicaragua, on September 2 starting at 6:40 a.m. local time. The emissions started slowly, but intensified. The ash plume began to dissipate after two hours of intense activity.
The volcano sent a plume of ash to 2,100 m. in height, according to the Volcanic Ash Advisory Center (VAAC) Washington.

According to Sinapred, the volcano's explosions occurred when the volcano cleared the debris caused by the landslide that blocked its crater. The eruptive activity did not show any alterations in the seismic amplitude data in real time (RSAM), and authorities do not expect a major eruption to be imminent.

 

Sources: Sinapred, VAAC Washington, Canal 12 nica

White Island, Whakatane webcam - ash show 20.09.2021 / 2:00 p.m. NZST - Doc. GeoNet

White Island, Whakatane webcam - ash show 20.09.2021 / 2:00 p.m. NZST - Doc. GeoNet

Since 6:50 a.m. on September 02, 2021, a minor ash emission has been observed from the active ventilation area at Whakaari / White Island by the web camera.

Satellite images indicate that a weak ash plume has now reached the area above the Bay of Plenty coast. This weak incineration phase follows on from the short episodes observed in recent weeks in Whakaari. Today's one is more sustained over time, and due to the direction of the north wind, traces of ash are transported to the Bay of Plenty.

Webcam images continue to show a nocturnal glow, suggesting temperatures in the active ventilation zone likely remain around 500-600 °C, according to recent observations.

The current level of activity corresponds to moderate levels of restlessness. As such, the Volcanic Alert Level remains at 2 and the Aviation Color Code remains at yellow.

 

Source: GeoNet

Kilauea - InSAR interferogram image 19.08.2021 / 01.09.2021, illustrating the magmatic intrusion south of Halema'uma'u. - Doc. USGS - One click to enlarge

Kilauea - InSAR interferogram image 19.08.2021 / 01.09.2021, illustrating the magmatic intrusion south of Halema'uma'u. - Doc. USGS - One click to enlarge

A synthetic aperture interferometric radar (InSAR) interferogram, derived from two passages of the COSMO-SkyMed satellite of the Italian Space Agency, on August 19 and September 1, 2021, illustrates the intrusion of magma in the southern region of the Kilauea's summit caldera, which occurred between August 23 and August 31, 2021. Each color cycle represents 1.55 cm of change in distance between the satellite and the ground (change in range).

The interferogram shows a maximum of 14 cm of range change, which could be generated by 18 cm of uplift generated by the intrusion of magma in the southern region of the caldera that occurred between 23 August and August 31. 2021.
Currently, soil deformation in the southern summit area of ​​Kilauea continues, albeit at a slower rate than seen last week.

Intrusions occurred in the 1960s, 1970s, early 1980s and more recently in 2006 and 2015. The only time an eruption occurred, following numerous intrusions, was in 1974.

 

Source: USGS - HVO

Kilauea - Time series plots of the hourly count of earthquakes in the Kīlauea summit region (top) and tilt at Sandhill station located southwest of the Kīlauea caldera (bottom). - Doc. HVO 22.08 / 31.08.2021 - one click to enlarge

Kilauea - Time series plots of the hourly count of earthquakes in the Kīlauea summit region (top) and tilt at Sandhill station located southwest of the Kīlauea caldera (bottom). - Doc. HVO 22.08 / 31.08.2021 - one click to enlarge

The VAAC Tokyo reports this September 2, 2021, a light and narrow plume of ash on Pagan / in the northern Marianas, based on visual observation and the low-altitude Goes satellite drifting 150 km west of the volcano this 3 September.

An ash scattering advisory was also issued on September 3.

The volcanic alert level is at Watch and the aviation code at Orange /

Pagan is monitored by satellite, by a seismic-acoustic network on Saipan, and seismic statios on Guamet Chichijima / Japan, by hydroacoustic data from Wake island.

 

Sources: USGS Northern Mariana, VAAC Wahington and Tokyo; CNMI homeland Security and Emergency management.

A crack that formed during an eruption of the North Pagan volcano in the Mariana Islands in 1981 crosses the summit of the volcano. Three main vents were active along the crack. U.S. Navy Photo, 1981 / via GVP

A crack that formed during an eruption of the North Pagan volcano in the Mariana Islands in 1981 crosses the summit of the volcano. Three main vents were active along the crack. U.S. Navy Photo, 1981 / via GVP

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Publié le par Bernard Duyck
Publié dans : #volcanic activity

During the last 24 hours (01.09.2021- 02.09.2021 / 08h00), the Taal volcano network recorded 19 volcanic earthquakes, including 3 volcanic tremor events lasting two to three minutes, 11 low frequency earthquakes, 5 hybrid earthquakes and a low level background tremor that has persisted since July 7, 2021.

The activity of the main crater was dominated by the rise of hot volcanic fluids in its lake which generated plumes 2,500 meters high which drifted towards the southwest. Sulfur dioxide emissions averaged 2,632 tonnes / day as of September 1, 2021. Based on soil deformation parameters from electronic tilt, continuous monitoring by GPS and InSAR, Taal Volcano Island started to deflate in April 2021 as the Taal region continues to experience very slow expansion. Since 2020.

Mirova announced a high thermal anomaly, of VRP 909 MW on September 2 at 5:10 am, not mentioned in the daily report of the Phivolcs.

Alert level 2 (increased unrest) prevails over the Taal volcano. DOST-PHIVOLCS reminds the public that at Alert Level 2, sudden explosions of steam or gas, volcanic earthquakes, minor ash falls and fatal accumulations or expulsions of volcanic gas can occur and threaten areas in and around TVI.

 

Sources: Phivolcs and Mirova

Taal - activity summary on 02.09.2021 - Doc. Phivolcs

Taal - activity summary on 02.09.2021 - Doc. Phivolcs

Taal - thermal anomaly of 09/02/2021 / 5:10 a.m. - Doc.Mirova _MODIS_logVRP

Taal - thermal anomaly of 09/02/2021 / 5:10 a.m. - Doc.Mirova _MODIS_logVRP

The USGS monthly report on Yellowstone, in Volcanic Alert Current Level Normal and Aviation Code Green, shows us in summary:

- background activity levels
- 97 localized earthquakes (max M3.1); no swarms (!)
- no change in the deformation style
- no eruption of the Steamboat Geyser (most recent date of July 8)

The earthquakes occurred on existing faults, triggered by increased pore pressure from additional groundwater that accumulated during the snowmelt. One of the things we are looking at to see if magma was involved are changes in soil deformation. No change in soil deformation during the month of July was outside the multi-year trends.

Yellowstone Volcano Observatory scientist Mike Poland discusses activity in Yellowstone in this monthly update recorded near Solitary Geyser in Yellowstone National Park.

https://www.facebook.com/USGSVolcanoes/videos/218681650120637

 

Source: Yellowstone Volcano Observatory

Yellowstone national Park - Morning Glory pool - photo archives © Bernard Duyck 2009 - one click to enlarge

Yellowstone national Park - Morning Glory pool - photo archives © Bernard Duyck 2009 - one click to enlarge

In Villarica, the Sernageomin reports for the month of July, emissions of whitish gases of varying intensity, little loaded with particulate matter. The plumes reach less than 600 meters above the crater.

The parameters suggest a stable behavior of the internal dynamics of the volcano, with the detection of minor thermal anomalies and the permanence of a lava lake at depth. The open duct condition and fluctuations in the lava lake can cause explosions that can affect the surroundings of the crater.

The technical alert for the month of July remained in Green.

 

Sources: Sernageomin & Laura Angarita

Villarica - activity from 01.09.2021 - photo Laura Angarita / Twitter

Villarica - activity from 01.09.2021 - photo Laura Angarita / Twitter

Eruptive activity continues in the northern crater of Mount Cerberus on Semisopochnoi Island. Several small explosions have occurred over the past 24 hours, detected by seismic and infrasound networks. High SO2 emissions continue to be observed in satellite data.

Small eruptions producing minor ash deposits near the active northern crater of Mount Cerberus and ash clouds generally less than 10,000 feet above sea level have characterized recent activity, which shows no sign of slowing down. Small explosions can continue to occur and could be difficult to detect, especially in bad weather.

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

 

Sources: AVO & Sentinel-2

Semisopochnoi - Continuous eruptive activity at Mt. Cerberus - image Sentinel-2 bands 12,11,4 from 01.09.2021 / Copernicus - one click to enlarge

Semisopochnoi - Continuous eruptive activity at Mt. Cerberus - image Sentinel-2 bands 12,11,4 from 01.09.2021 / Copernicus - one click to enlarge

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
Etna - hot spots at the summit craters and other lava flows of the paroxysm of 08/29 - image Sentinel-2  bands 12,11,4 of 08/30/2021 - one click to enlarge

Etna - hot spots at the summit craters and other lava flows of the paroxysm of 08/29 - image Sentinel-2 bands 12,11,4 of 08/30/2021 - one click to enlarge

Etna - SO2 plume of paroxysm over the Greek islands on 08/30/2021 - Sentinel-5P image via Adam platform - one click to enlarge

Etna - SO2 plume of paroxysm over the Greek islands on 08/30/2021 - Sentinel-5P image via Adam platform - one click to enlarge

After the paroxysm of August 29, whose satellites show the extent of the field of lava flows and the extension of the sulfur dioxide plume following the eruption, a weak Strombolian activity resumed at the south-eastern crater of Etna on August 30 at around 8 p.m. UTC,
The trend of the mean amplitude of the volcanic tremor, from 20:00 UTC, is characterized by fluctuations on medium-low values. This activity ceased on August 31 at the end of the day.

The center of gravity of the volcanic tremor sources is located in the crater of Bocca Nuova at an altitude of about 2,700 m above sea level. Infrasonic activity is kept at low levels.

 

Source: INGV OE, Sentinel-5P and Sentinel-2

Etna - trémor on 01.09.2021 - Doc. INGV OE

Etna - trémor on 01.09.2021 - Doc. INGV OE

During the week of August 23-30, Sabancaya maintained moderate-level activity, with an average of 36 explosions per day, accompanied by ash and gas plumes reaching 3,500 m. above the summit.

I.G.P. recorded and analyzed 1,198 earthquakes of volcanic origin, associated with the circulation of magmatic fluids.

No significant deformation anomalies.

Mirova detected 10 thermal anomalies, with a max. of 27 MW VRP, associated with the presence of a surface lava body in the crater.

The alert level is maintained in Naranja, with an inaccessible area of 12 km in radius.

 

The activity continues.

 

Sources: I.G. Peru & Ingemmet

Sabancaya - summary of the activity from 23 to 30 August 2021 - photo I.G. Peru

Sabancaya - summary of the activity from 23 to 30 August 2021 - photo I.G. Peru

Sabancaya - explosions continue - 08.31.2021 / 11.57am - Cam. Ingemmet - OVI

Sabancaya - explosions continue - 08.31.2021 / 11.57am - Cam. Ingemmet - OVI

In August 2021, the OVPF recorded in the Piton de la Fournaise massif in total:
- 37 superficial volcano-tectonic earthquakes (0 to 2.5 km above sea level) under the summit craters
- 2 deep earthquakes (below sea level);
- 311 collapses (in the Crater Dolomieu, the ramparts of the Enclos Fouqué and Piton de Crac, and the Rivière de l'Est).

The inflation of the building, initiated in April 2021, continued throughout August 2021. This inflation showed a pressurization of the superficial magmatic reservoir located around 1.5-2 km deep .

Piton de La Fournaise - Illustration of the deformation over the last six months from March 1 to August 31, 2021 (eruptive periods are in red). The variations in distance between two GPS receivers crossing the Piton de la Fournaise building, at the top (BOMG reference; above), at the base of the terminal cone (FOAG reference; in the middle) and in the far field (reference PRAG; bottom). A rise is synonymous with elongation and therefore swelling of the volcano; conversely a decrease is synonymous with contraction and therefore deflation of the volcano (© OVPF-IPGP)

Piton de La Fournaise - Illustration of the deformation over the last six months from March 1 to August 31, 2021 (eruptive periods are in red). The variations in distance between two GPS receivers crossing the Piton de la Fournaise building, at the top (BOMG reference; above), at the base of the terminal cone (FOAG reference; in the middle) and in the far field (reference PRAG; bottom). A rise is synonymous with elongation and therefore swelling of the volcano; conversely a decrease is synonymous with contraction and therefore deflation of the volcano (© OVPF-IPGP)

The inflation of the building and the CO2 contents in the soil which remained high in August 2021, witnessed magmatic transfers from deep zones to the superficial magmatic reservoir which continued after the end of the eruption of April 9-May 24, 2021.

 

Source: OVPF - monthly bulletin

Soufriere of St. Vincent - the crater on 08/30/2021 - Doc. UWI-SRC - one click to enlarge

Soufriere of St. Vincent - the crater on 08/30/2021 - Doc. UWI-SRC - one click to enlarge

Seismic activity at La Soufrière in St. Vincent has remained low since the tremor associated with the explosion and ash removal on April 22. Over the past week, there has been a slight increase in magnitude, but this has provided no indication of reactivation.
Current activity corresponds to a period of unrest after a rash. This can last for weeks or even months. While volcanic activity is on the decline, there is the continued presence of hot spots near the surface, daily seismic activity, and persistent outgassing.

Lahar signals were observed: 4 on August 24, and 1 on August 25, related to the precipitation that was recorded during this period.
Clear weather conditions at the volcano on August 30 allowed excellent views of the crater and observations indicate that no major changes have occurred in the crater since the end of explosive activity on April 22.
There is a small, but not insignificant, possibility that magma activity will resume in the event of an influx of new magma from the depths.


The volcano remains at the ORANGE alert level.

 

Source: UWI-SRC 08.31.2021 / 1:00 p.m.

Nevado del Ruiz - sporadic gas and ash emissions on 08/30/2021 / 07:08 am - photo Ingeominas

Nevado del Ruiz - sporadic gas and ash emissions on 08/30/2021 / 07:08 am - photo Ingeominas

The Nevado del Ruiz, in unstable conditions, continues an activity characterized by constant degassing and sporadic ash emissions.
The gas-vapor plumes containing a certain amount of ash reached approx. 5,800 m above sea level and extended west-northwest of the volcano.
Seismic activity is mainly concentrated under the Arenas crater and under the NE and SE flanks of the volcano with a downward trend this week.


The alert level for the volcano remains at "yellow".


Sources: Servicio Geológico Colombiano, Ingeominas.

Fagradalsfjall - vent # 5 active in the fog 08.31.2021 / 2:01 p.m. - RUV webcam - one click to enlarge

Fagradalsfjall - vent # 5 active in the fog 08.31.2021 / 2:01 p.m. - RUV webcam - one click to enlarge

Fagradalsfjall - lava flows in three directions on 31.008.2021 - Photo VOLCAPSE - one click to enlarge

Fagradalsfjall - lava flows in three directions on 31.008.2021 - Photo VOLCAPSE - one click to enlarge

Some news from Fagradalsfjall, under heavy fog / cloud cover (no satellite images).

On August 31, the lava emitted by vent # 5 flowed mainly into Meradalur to the east, but also to Geldingadalur to the south, and Upper Meradalur to the southeast.

The activity remains fluctuating as shown by the variations of the tremor.

 

Sources: Hraun.vedur & Volcapse

Fagradalsfjall - tremor at 01.09.2021 - Doc. Hrau, .vedur.is

Fagradalsfjall - tremor at 01.09.2021 - Doc. Hrau, .vedur.is

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Karymsky - plume of an explosion at more than 2,500 m.asl. - photo 27.08.2021 -N. Gorbach. / IVS FEB RAS

Karymsky - plume of an explosion at more than 2,500 m.asl. - photo 27.08.2021 -N. Gorbach. / IVS FEB RAS

Moderate eruptive activity of the Karymsky volcano continues. According to satellite data, an ash plume extends 42 km east-northeast of the volcano.

Moderate eruptive activity of the volcano continues. Ash explosions up to 6-7 km. altitude. could arise at any time. The current activity could affect low-flying aircraft.
Volcanic cloud height: 1500-1600 m (4920-5248 ft) AMSL Time and method of ash plume / cloud height determination: 20210827 / 0430Z - Himawari-8
Distance of ash plume / cloud of the volcano: 42 km (26 mi)
Direction of drift of ash plume / cloud of the volcano: ENE / azimuth 75 deg

 

Source : KVERT

Kilauea - intrusive activity from 23 to 30 August 2021 - Doc.HVO - one click to enlarge

Kilauea - intrusive activity from 23 to 30 August 2021 - Doc.HVO - one click to enlarge

The map above illustrates the intrusive activity detected over the past week at the Kīlauea volcano. The initial swarm of small earthquakes from August 23 to 25 was centered in the southern region of the caldera, as shown on the map. A second swarm started late August 26 in the same area; the number of earthquakes dropped the next day, but they stayed above background levels and the epicenters moved away from the caldera towards the Southwest Rift Connector.

In the past 24 hours, around 98 earthquakes have been recorded at the top of Kīlauea and south of the Kīlauea caldera. Most of the earthquakes were below magnitude 2 and occurred about 1-4 km (0.6-2.5 mi) below the surface. These small earthquakes occurred up to 8 earthquakes detected per hour. These earthquake rates are significantly lower than those seen during pulses of activity last week.

Ground deformation, as measured by inclinometers and GNSS (GPS) instruments, appears to be concentrated in the dotted ellipse on the map. The Southwest Rift Connector (also labeled on the map) is an underground passage for magma in the Southwest Rift Zone of Kīlauea, and for decades it has been a known source area for seismicity. The connector region is offset to the southeast from the main lineament of the eruptive vents marking the Southwest Rift Zone, as evidenced by the 1971 eruptive vents and the 1919-1920 Maunaiki Lava Shield on the map. Eruptions from the connector itself are believed to be rare, although a brief but dramatic eruption occurred in this region on December 31, 1974, producing a lava flow that traveled over 12 km (7.5 mi). towards the southwest.

The volcanic alert remains in advisory and the aviation code in Yellow.

 

Sources: HVO daily reports

Suwanosejima - 08.30.2021 / 6:39 p.m. - JMA webcam

Suwanosejima - 08.30.2021 / 6:39 p.m. - JMA webcam

The activity of Suwanosejima continues.

An eruptive episode occurred at Suwanosejima (Mount Ontake Crater) at 9:22 p.m. on August 30, and the eruption plume rose 2,800 m above the crater rim.
The volcanic ash drifts, t towards the southwest of the crater, and within an hour there was a fairly large amount of ash in the village of Toshima,

Another eruptive episode occurred at 10:22 a.m. on August 31, and the plume rose 1,800 m above the crater rim. Volcanic ash was carried westward from the crater, and at 4:00 p.m. on the 31st, there was a small ashfall in Toshima Village, and Kagoshima Prefecture.

 

Source: JMA

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Etna - the activity of 08/29/2021 / 3:56 p.m. - Doc. INGV OE

Etna - the activity of 08/29/2021 / 3:56 p.m. - Doc. INGV OE

At 3:25 p.m. local time on August 29, 2021, Strombolian activity resumed at the south-eastern crater of Etna.

From 12:00 UTC there is a significant increase in the amplitude of the tremor, which reaches high values ​​(red area). This phenomenon is also followed by an increase in infrasonic activity, with approximately 1 event per minute. The sources of the tremor are located to the SE of the SE crater, at a level of about 3000 m. altitude Over the past few hours, there has been no significant change in the distortion to the GPS and tilt networks.

At 3:45 p.m. GMT, there is an increase in Strombolian activity with passage to a lava fountain. There is a further increase in the amplitude of the tremor, which reaches high values. Infrasonic activity also increased, both in terms of frequency and amplitude of signals. The sources of the tremor are located SE of the SE crater, at a level of approx. 3.000 m. altitude.

Etna SEC - 08/29/2021 / 3:57 p.m. and 4 p.m., LAVE and INGV webcams respectively - one click to enlargeEtna SEC - 08/29/2021 / 3:57 p.m. and 4 p.m., LAVE and INGV webcams respectively - one click to enlarge

Etna SEC - 08/29/2021 / 3:57 p.m. and 4 p.m., LAVE and INGV webcams respectively - one click to enlarge

Etna SEC - 08/29/2021 / 5:57 p.m. and 5:51 p.m., LAVE and INGV webcams respectively - one click to enlargeEtna SEC - 08/29/2021 / 5:57 p.m. and 5:51 p.m., LAVE and INGV webcams respectively - one click to enlarge

Etna SEC - 08/29/2021 / 5:57 p.m. and 5:51 p.m., LAVE and INGV webcams respectively - one click to enlarge

Etna SEC - fountaining characterizes this n ° paroxysm on 29.08.2021  - photos Gio Giusa
Etna SEC - fountaining characterizes this n ° paroxysm on 29.08.2021  - photos Gio Giusa

Etna SEC - fountaining characterizes this n ° paroxysm on 29.08.2021 - photos Gio Giusa

The INGV announces at 18:27 UTC that the explosive activity continues at the South-East summit craters. This activity produced two lava flows, one towards the Valle del Bove and the other towards the southwest, the latter encircling the Monte Frumento Supino. The flow fronts are still active. The fallout of ash and lapilli affected the municipalities of: Milo, Sant'Alfio, Giarre, Fornazzo.

The thermal anomalies, noted by Mirova, are very important: VRP 2551 MW on 08/29/9:40 p.m. and VRP 1114 MW on 08/30/00:20 a.m.

 

The explosive activity at the SEC ceased at 20:37 UTC. The lava flows are cooling. The amplitude of the tremor is currently at medium-high levels. The signal sources are located SE of the SE crater. The infrasonic activity has practically ceased.
The soil deformations recorded on the clinometric network were exhausted, which revealed, during the lava fountain, variations of up to about 2 microradians at the Cratere del Piano (ECP) station.

 

Source: INGV OE and the photographers mentioned

Etna SEC - paroxysm 08.29.2021 - photo EtnaWalk

Etna SEC - paroxysm 08.29.2021 - photo EtnaWalk

Etna - trémor at 08.30.2021 / 06h00 - Doc. INGV OE

Etna - trémor at 08.30.2021 / 06h00 - Doc. INGV OE

Etna - La Signora degli Anelli ... a perfect ring to be forgiven for the ashes emitted - photo Gio Giusa 08.29.2021

Etna - La Signora degli Anelli ... a perfect ring to be forgiven for the ashes emitted - photo Gio Giusa 08.29.2021

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Merapi summit, seen from the SW in the fog on 25.08.2021 - photo- Andi volcano

Merapi summit, seen from the SW in the fog on 25.08.2021 - photo- Andi volcano

From August 20 to 26, at Merapi on Java, there were 2 pyroclastic flows in the southwest with a maximum glide of 2,000 m. Incandescent boulder falls have been observed 211 times to the southwest with a maximum sliding distance of 2,000 m.

Morphological changes are observable in the southwest lava dome, the height of the dome has increased by about 3 m., While the central dome is relatively fixed.

The volume of the southwest lava dome is 1,400,000 m³ and the central dome is 2,831,000 m³.

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. the ejection of volcanic material in the event of an explosive eruption can reach a radius of 3 km from the summit.

 Merapi - risk maps at 25.08.2021 - Doc. BPPTKG

Merapi - risk maps at 25.08.2021 - Doc. BPPTKG

Merapi - seismicity of the week and number of earthquakes on 08/27/2021 - Doc. BPPTKG

Merapi - seismicity of the week and number of earthquakes on 08/27/2021 - Doc. BPPTKG

On August 27, the seismicity changed facies with:

- 1 pyroclastic flow collapse earthquake, with an amplitude of 75 mm and a duration of 150 seconds.
- 262 collapse / avalanche earthquakes, with an amplitude of 3-43 mm and an earthquake duration of 12-136 seconds.
- 494 blast / emission earthquakes, with an amplitude of 3 to 6 mm and an earthquake duration of 7 to 43 seconds.
- 48 low frequency earthquakes, with an amplitude of 3 to 8 mm and an earthquake duration of 9 to 20 seconds.
- 48 hybrid / multiphase earthquakes, with an amplitude of 3 to 24 mm, S-P from 0.3 to 0.7 seconds and a duration of 6 to 17 seconds.
- 2 distant tectonic earthquakes.

The activity level remains at 3 / siaga.

 

Source: BPPTKG

Rincon de La Vieja - 08.28.2021 - photo Ovsicori

Rincon de La Vieja - 08.28.2021 - photo Ovsicori

Three small phreatic eruptions were recorded on August 27, 2021 at Rincon de La Vieja, respectively at 19:15, 20:49 and 20:53 local time. The most important happened at 8:49 p.m. There was no visibility, no report. Duration of the activity: 2 minutes.

At 2:46 p.m. local time on August 28, 2021, a phreatic eruption was recorded at the Rincon de la Vieja volcano, with a column that rises 1,000 meters above the height of the crater and 2,916 m above sea level. altitude. At the time of this report, the winds are blowing from the southwest.
Duration of activity: 1 minute.
Seismic activity is higher than yesterday.
The amplitude of the tremor increased after this event in particular in the low frequencies of approximately 1 hour at the beginning of the night. Until the moment of this report, the tremor remains with a greater amplitude than the day before.

 

Source: Ovsicori

Kilauea - Halema'uma'u crater - USGS photo by M. Patrick

Kilauea - Halema'uma'u crater - USGS photo by M. Patrick

The Kīlauea volcano is not erupting. However, intrusive activity, which began on August 23, continues south of the Kīlauea caldera.

From the evening of August 26, soil deformation in the southern summit region of Kīlauea resumed at the highest rates seen during the first intrusive pulse spanning August 23 to 25. On the other hand, the current seismic activity remains low compared to the previous impulses of this intrusive activity. The East Rift Zone remains calm.
The rate of soil deformation under the southern portion of the Kīlauea Summit region in Hawai'i Volcanoes National Park began to increase again on the evening of August 26 and continues to this time. These observations suggest that magma continues to fuel the ongoing intrusion.

In the past 24 hours, around 80 earthquakes have been recorded at the top of Kīlauea and south of the Kīlauea caldera. Most of the earthquakes were less than magnitude 2 and occurred about 1 to 4 km (0.6 to 2.5 mi) below the surface. These small earthquakes occurred at a frequency of up to 7 detected earthquakes per hour. These earthquake rates are significantly lower than the rates seen earlier this week.

Activity continues, but there is no indication of upward migration of earthquakes to the surface or change in deformation that would indicate a decrease in the depth of source intrusive activity. As a result, Kīlauea's Volcanic Alert Level and Aviation Color Code remain at Advisory / Yellow.

 

Source: HVO

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 Fukutoku Okanoba - morphological changes due to erosion on 08/26/2021 / 1:07 p.m. - photo Japan Coast Guards - one click to enlarge

 Fukutoku Okanoba - morphological changes due to erosion on 08/26/2021 / 1:07 p.m. - photo Japan Coast Guards - one click to enlarge

Fukutoku Okanoba - morphological changes on 08/26/2021 / 1:07 p.m. of the western crescent of Niijima - photo Japan Coast Guards - one click to enlarge

Fukutoku Okanoba - morphological changes on 08/26/2021 / 1:07 p.m. of the western crescent of Niijima - photo Japan Coast Guards - one click to enlarge

An overview of the eruptive site of Fukutoku Okanoba on August 26, 2021 by the Japanese coast guard shows a strong erosion of the eastern crescent of Niijima.

Professor Kenji Nogami, Volcanic Fluid Research Center, Tokyo Institute of Technology (on board the plane) give comments on the situation:
・ Niijima on the west side has not changed significantly and remains as land for some time.
・ A gray substance that appears to be volcanic ash erupts from the center of the crater, causing a brownish-brown color.
The colored waters are also distributed on a large scale and active volcanic activity is still ongoing.

 

Sources : Japan Coast Guards & JMA

Fukutoku Okanoba - the coloring of the waters testifies to a volcanic activity still ongoing on 08/26/2021 / 12:50 p.m. - photo Japan Coast Guards - one click to enlarge

Fukutoku Okanoba - the coloring of the waters testifies to a volcanic activity still ongoing on 08/26/2021 / 12:50 p.m. - photo Japan Coast Guards - one click to enlarge

An eruption occurred at Suwanosejima (Mount Ontake Crater) at 12:31 p.m. on August 28, and smoke from the eruption rose 4,800 m above the crater rim.

The ashes scattered north, and a large amount fell on the village of Toshima. An area 2 km north of the volcano is considered at risk.

The rash continues.

 

Sources: JMA & VAAC Tokyo

Suwanosejima - plume of the eruptive episode of 08/28/2021 / 12:31 - photo inouezoo_tokara / Twitter

Suwanosejima - plume of the eruptive episode of 08/28/2021 / 12:31 - photo inouezoo_tokara / Twitter

The US Geological Survey's Hawaiian Volcanoes Observatory (HVO) has detected a resumption of seismic activity and soil deformation below the southern portion of the Kīlauea Summit Caldera in Hawaii Volcanoes National Park 'i. The rate of soil deformation started to increase again around 6:00 p.m. HST on August 26 and was followed by an increase in seismic activity after 8:30 p.m. The resumption of activity occurred at roughly the same location as the earthquake swarm of August 23-25, inside and south of the Kīlauea caldera. The combination of these observations indicates a second pulse of intrusive activity.

No indication of upward migration of earthquakes to the surface or change in deformation that would indicate a shallow depth of source intrusive activity. As a result, Kīlauea's Volcanic Alert Level and Aviation Color Code remain at Advisory / Yellow.

While activity slowed by the morning of August 27, additional intrusion pulses are possible. Any potential eruptive activity related to these events would be entirely within Hawai'i Volcanoes National Park and localized in undeveloped areas, well away from infrastructure such as roads.

 

Source: HVO

Map showing seismic activity under the southern portion of the Kīlauea Caldera in Hawai'i Volcanoes National Park from August 23, 2021 at 12:15 p.m. until August 25, 2021 at the same time. The map shows the locations of earthquakes, with earthquakes colored by the time they occurred and their magnitude (see key at the bottom of the figure). The plots above and below the map show the depth of the earthquake below sea level (0) by longitude (bottom) and depth below sea level (0) by latitude (top) , with lines of longitude and latitude corresponding to the map. USGS map and tracks. - one click to enlarge

Map showing seismic activity under the southern portion of the Kīlauea Caldera in Hawai'i Volcanoes National Park from August 23, 2021 at 12:15 p.m. until August 25, 2021 at the same time. The map shows the locations of earthquakes, with earthquakes colored by the time they occurred and their magnitude (see key at the bottom of the figure). The plots above and below the map show the depth of the earthquake below sea level (0) by longitude (bottom) and depth below sea level (0) by latitude (top) , with lines of longitude and latitude corresponding to the map. USGS map and tracks. - one click to enlarge

1724 / 5000 Résultats de traduction Kilauea, Halema'uma'u - the weather is overcast on the lava lake and the summit caldera on 08/27/2021 / 07:40 a.m. - HVO webcam - one click to enlarge

1724 / 5000 Résultats de traduction Kilauea, Halema'uma'u - the weather is overcast on the lava lake and the summit caldera on 08/27/2021 / 07:40 a.m. - HVO webcam - one click to enlarge

The crater of Nyiragongo volcano is completely empty. On social networks, comments are numerous after the broadcast of the video of the flyby of August 26, 2021. Some even go so far as to insinuate that the famous volcano is now extinct.

Nyiragongo - image Sentinel-2 bands 4,3,2 & 12,11,8A from 08.25.2021 / via Monts project & the crater during the flyby on 08.26.2021 / via Dr. Balagizi
Nyiragongo - image Sentinel-2 bands 4,3,2 & 12,11,8A from 08.25.2021 / via Monts project & the crater during the flyby on 08.26.2021 / via Dr. Balagizi

Nyiragongo - image Sentinel-2 bands 4,3,2 & 12,11,8A from 08.25.2021 / via Monts project & the crater during the flyby on 08.26.2021 / via Dr. Balagizi

Dr. Charles Balagizi, volcanologist at the Volcanological Observatory (OVG) in Goma since 2009, made an update point : The Nyiragongo volcano is not extinct.

The absence of a lava lake does not mean that Nyiragongo is extinct or that it will no longer erupt. It is a fairly young volcano that is around 15,000 years old, and will certainly remain active for a long time.
The Nyiragongo crater is indeed empty, and this is quite normal because the lava it contained was emptied from the southern flank of the volcano during the last eruption on May 22, 2021.
 It is necessary to wait for the magma to rise from the deep and superficial magmatic chambers towards the surface, passing through the magmatic pipe. This chimney is currently clogged with products (a thick layer of rock and ash) from the collapse of parts of the crater platforms.

Source: Dr. Charles Balagizi 

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