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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
Fukutoku-Okanoba - plume of steam and gas at 6,000 meters, spreading out like an umbrella. - photo Japan Coast Guards 08/13/2021, taken about 90 km north of Fukutoku Okanoba and about 6000 m above sea level. - one click to enlarge

Fukutoku-Okanoba - plume of steam and gas at 6,000 meters, spreading out like an umbrella. - photo Japan Coast Guards 08/13/2021, taken about 90 km north of Fukutoku Okanoba and about 6000 m above sea level. - one click to enlarge

South Iwo Jima (left) and Niijima in Fukutoku- Okanoba (right) - Japan Coast Guards 08.15.2021 / 12:47 - one click to enlarge

South Iwo Jima (left) and Niijima in Fukutoku- Okanoba (right) - Japan Coast Guards 08.15.2021 / 12:47 - one click to enlarge

Fukutoku-Okanoba - a break in the activity shows the horseshoe structure - photo Japan Coast Guards 08.15.2021 / 12:45 p.m.

Fukutoku-Okanoba - a break in the activity shows the horseshoe structure - photo Japan Coast Guards 08.15.2021 / 12:45 p.m.

Fukutoku-Okanoba - activity on 08.15.2021 / 12.51pm - photo Japan Coast Guards - one click to enlarge

Fukutoku-Okanoba - activity on 08.15.2021 / 12.51pm - photo Japan Coast Guards - one click to enlarge

Observation overflights were carried out in Fukutoku-Okanoba by the Japan Coast Guards teams on August 13 and 15, 2021.

They make it possible to specify that the initial eruptive plume of gas and vapor rose to an altitude estimated at 16 km. and unfolded as an umbrella.

Several international flights between Japan and the Philippines were canceled on August 15 due to possible ash emissions

This August 15, black jets of the "surtseyen" type were visible in the plume of gas and steam, above the horseshoe structure on the Coast Guard video (2021 / 8/15 12:40 -13: 10 - https://www1.kaiho.mlit.go.jp/GIJUTSUKOKUSAI/kaiikiDB/video/fukutoku/fuku210815.mp4)

 

Source: Japan Coast Guards

Sheveluch - expulsion of juvenile materials at the lava dome - photo Y.Demyanchuk / KVERT 08.10.2021

Sheveluch - expulsion of juvenile materials at the lava dome - photo Y.Demyanchuk / KVERT 08.10.2021

Sheveluch -15.08.2021 / 00h41 images Sentinel-2 bands 12,11, 8A & Modis thermal volcanic activity - Doc. Mirova

Sheveluch -15.08.2021 / 00h41 images Sentinel-2 bands 12,11, 8A & Modis thermal volcanic activity - Doc. Mirova

Sheveluch - thermal anomalies at 08.16.2021 / 03h00 - Doc. Mirova_MODIS_Latest10NTI

Sheveluch - thermal anomalies at 08.16.2021 / 03h00 - Doc. Mirova_MODIS_Latest10NTI

At Sheveluch, the growth of the lava dome continues; it is accompanied by strong fumarole activity, the incandescence of the dome, and avalanches of blocks.

A plume of gas and vapor, containing small amounts of ash is noted at 3,000-3,500 m. altitude, extending up to 33 km. at the ESE of the volcano.

The aviation code remains orange, due to the continuation of the extrusive eruption.

Mirova detected thermal anomalies with a max. of VRP 873MW this August 15.

 

Sources: KVERT, Mirova and VAAC Tokyo

Fagradalsfjall -image Sentinel-2 bands 8,4,3 IR from 13.08.2021

Fagradalsfjall -image Sentinel-2 bands 8,4,3 IR from 13.08.2021

Fagradalsfjall - 08.13.2021, at 1:49 p.m. and 1:50 p.m. respectively - lava overflow at the active crater - mbls webcam
Fagradalsfjall - 08.13.2021, at 1:49 p.m. and 1:50 p.m. respectively - lava overflow at the active crater - mbls webcam

Fagradalsfjall - 08.13.2021, at 1:49 p.m. and 1:50 p.m. respectively - lava overflow at the active crater - mbls webcam

In Fagradalsfjall, the eruption continues with vigor.

Video footage from August 13 shows a crater disgorging its lava in waves in multiple flows towards Meradalur; a piece of the crater wall was washed away by these lava waves.

The eruption paused on August 15 around 5:35 am, and in less than a minute, according to webcams ... but seems to continue according to a receding pattern.

 

Sources: mbls, Volcano Raging and GutnTog videos, Hraun.vedur

Fagradalsfjall - the crater active on 08.15.2021 / 5.14 a.m. - mbls webcam

Fagradalsfjall - the crater active on 08.15.2021 / 5.14 a.m. - mbls webcam

Fagradalsfjall - tremor at 16.08.2021 - Doc. Hraun.vedur

Fagradalsfjall - tremor at 16.08.2021 - Doc. Hraun.vedur

Fagradalsfjall - 08.13.2021 - Fire & Iceland Volcano Raging video

The active crater active in smoke and VOG on 08.14.20210 - video GutnTog

At Montagne Pelé / La Martinique, between August 6 and 13, the OVSM recorded at least 29 volcano-tectonic earthquakes of magnitude less than or equal to 0.2 (since the lightning of the night of June 29 to 30, 82% of the Montagne Pelée seismological station network and 86% of the volcano's deformation detection network are operational). The previous week, between July 30 and August 6, 121 earthquakes were recorded.

These earthquakes were located inside the volcanic edifice between 0.3 km above sea level and the surface. None of these earthquakes were felt by the population. This volcano-tectonic-type superficial seismicity is associated with the formation of microfractures in the volcanic edifice.

 

A degassing zone at sea was detected at shallow depth (between Saint-Pierre and Le Prêcheur). "The IPGP is currently setting up experiments to map this zone of gas emanations, carry out physicochemical measurements of the fluids and samples of these fluids in order to constrain the origin of this degassing and to assess its relationship possible with the hydrothermal system of Mount Pelée ”, indicates the OVSM.

The alert level remains on Yellow alert.

 

Sources: OVSM & France Antilles / La Martinique

La Montagne Pelée / Martinique - photo 1977 - R.Fiske Smiths.

La Montagne Pelée / Martinique - photo 1977 - R.Fiske Smiths.

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
Taal - rising sulfur dioxide emissions generate VOG - photo archives reportrdotworld

Taal - rising sulfur dioxide emissions generate VOG - photo archives reportrdotworld

In the past 24 hours, the Taal Volcano network has recorded 27 volcanic tremor events lasting one to 45 minutes and one low-level bottom 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 2000 meters high that drifted northeast.

Sulfur dioxide emissions averaged 9,025 tonnes / day on August 14, 2021. In addition, VOG was observed over the Taal volcano and its surroundings.

Based on ground deformation parameters from electronic tilt, GPS and InSAR continuous monitoring, Taal Volcano Island began to deflate in April 2021 as the Taal region continues to decline. undergo a very slow expansion since 2020.


Alert Level 2 (increased unrest) now prevails over 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. DOST-PHIVOLCS strongly recommends that entry be strictly prohibited into the volcanic island of Taal, the permanent danger zone or PDZ of Taal, especially the surroundings of the main crater and the Daang Kastila fissure, as well as the occupation and boating on Taal Lake.

 

Source: Phivolcs

Taal - summary of activity of 08.15.2021 - Doc.Phivolcs

Taal - summary of activity of 08.15.2021 - Doc.Phivolcs

Three volcanoes are in aviation code orange in Alaska, the Pavlof, the Great Sitkin and the Semisopochnoi.

 

Three small explosions were detected on the infrasound sensors of the Pavlof volcano during the last day. Web camera footage this morning confirmed a small ash emission from the most recent of them. Like all other explosions seen during the current eruption, the ash appeared to dissipate quickly and the deposits were confined to areas near the vent.

High surface temperatures and small earthquakes were detected during the last day at the Great Sitkin volcano, which corresponds to the continued growth of a lava dome. A plume of steam and gas could be seen above the summit on clear satellite images from the web camera. No explosion or ash emission was detected.

During the last day, four small explosions were detected from the North Cerberus crater in Semisopochnoi on infrasound and seismic sensors. Clear images from the web camera showed nearly continuous ash emissions, including during periods with no explosion detected. Overnight, satellites detected a low-level ash plume below 10,000 feet above sea level extending to Kiska about 100 to 200 miles west (200 to 300 km).

Source: AVO

Semisopochnoi island - photo Steve Ebbert, 1997 (U.S. Fish and Wildlife Service) / GVP-09492

Semisopochnoi island - photo Steve Ebbert, 1997 (U.S. Fish and Wildlife Service) / GVP-09492

The KVERT indicates four volcanoes in aviation code orange, from north to south, in Kamchatka and in the Kurils: the Sheveluch, the Karymsky, the Ebeko, the Chirinkotan.

 

Sheveluch (Kamchatka): The explosive activity continues. The Volcanic Ash Advisory Center (VAAC) Tokyo has warned of a plume of volcanic ash that rises to an estimated altitude of 15,000 feet (4,600 m) or flight level 150 and moves at 10 knots in a SE direction .

Karymsky (Kamchatka): The explosive activity continues. The VAAC Tokyo has warned of a volcanic ash plume that has risen to an estimated altitude of 8,000 feet (2,400 m) or flight level 080 and is moving at 10 kts in the S direction.

 

Source: KVERT & VAAC Tokyo

Karymsky - photo G. Volynets / kscnet.ru- IVS - kvert via K. Bakanov

Karymsky - photo G. Volynets / kscnet.ru- IVS - kvert via K. Bakanov

In the Ogasawara Islands,

the eruption of the submarine volcano Fukutoku-Okanoba continues, with the emission of steam plumes drifting westward and being able to reach the coasts of the Asian continent during the day.

Explosive activity has resumed and continues in Nishino-shima. VAAC Tokyo has warned of a volcanic ash plume rising to an estimated altitude of 2100 m., or flight level 070 and moving at 10 kts in the NE direction.

 

Source: VAAC Tokyo

Fukutoku-Okanoba plume - Himawari image sat. 14.08.2021 / 14:40

Fukutoku-Okanoba plume - Himawari image sat. 14.08.2021 / 14:40

Fukutoku- Okanoba - Volcanic ash advisory 15.08.2021 / 0603Z - Doc. VAAC Tokyo

Fukutoku- Okanoba - Volcanic ash advisory 15.08.2021 / 0603Z - Doc. VAAC Tokyo

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
 Fukutoku - eruptive plume with lightning on 13.08.2021 - photo Misoka_Fumituki / JMA

 Fukutoku - eruptive plume with lightning on 13.08.2021 - photo Misoka_Fumituki / JMA

The eruption of the submarine volcano Fukutoku - Okanoba, in the Ogasawara Islands, which began on August 13, 2021 continues.

The eruptive plume of white vapor, traversed by lightning caused by the friction of the pyroclasts expelled at high speed, continues to be emitted and to drift in a west-southwest direction.

The Sentinel-5P / Tropomi satellite recorded a strong plume of sulfur dioxide 35 km from the volcano and 3 km. of altitude, with 18.53 DU of SO2. The estimated mass at 300 km is 6.5 kilotons.

 

Sources: JMA, VAAC Tokyo, Tropomi / Sentinel-5P, Kyodo news

The Japanese Meteorological Agency announced on the 13th that an eruption would have occurred on the submarine volcano "Fukutoku Okanoba", located about 50 kilometers south of the islands of Ogasawara and Iwo Jima. - Kyodo news video

Fukutoku - extension of the eruptive plume on 08.13.2021 / 08:20 UTC - sat. Himawari-8

Fukutoku - extension of the eruptive plume on 08.13.2021 / 08:20 UTC - sat. Himawari-8

Fukutoku - Volcanic ash advisory 14.08.2021 / 0606Z - Doc. VAAC Tokyo

Fukutoku - Volcanic ash advisory 14.08.2021 / 0606Z - Doc. VAAC Tokyo

Fukutoku - strong plume of sulfur dioxide on 08.13.2021, 35 km from the volcano and 3 km. altitude, with 18.53 DU of SO2 - Doc. Tropomi / DLR - BIRA - ESA

Fukutoku - strong plume of sulfur dioxide on 08.13.2021, 35 km from the volcano and 3 km. altitude, with 18.53 DU of SO2 - Doc. Tropomi / DLR - BIRA - ESA

The eruption of a lava dome in the summit crater of the Great Sitkin volcano continued over the past week.

Satellite data showed the dome grew from around 300m in diameter on August 6 to around 380m on August 9. Plumes of steam were visible in satellite and web camera images, but no ash emission was detected. Small earthquakes were detected which are probably associated with the lava effusion. No explosive activity was detected.
There is no indication of how long the lava flow lasted during the current eruption, and it is possible that explosive activity could occur with little or no warning.

The volcanic alert remains at Watch and the aviation code at Orange

The Great Sitkin volcano is monitored by local seismic and infrasound sensors, satellite data, web cameras, and remote infrasound and lightning networks.

 

Sourec: AVO

Great Sitkin - the growing dome - photo Peggy Kruse 10.08.2021 / AVO

Great Sitkin - the growing dome - photo Peggy Kruse 10.08.2021 / AVO

Location of the Great Sitkin in the Aleutian volcanic arc - AVO map

Location of the Great Sitkin in the Aleutian volcanic arc - AVO map

A moderate eruptive activity continues in Chirinkotan, in the Kuril archipelago, with this August 14, 2021 at 02:15 UTC, an explosive episode, accompanied by a plume of gas at 3,000 - 3,500 m asl., drifting 12 km towards the SSE of the volcano.

The aviation code remains orange, other strong explosions can occur at any time, with potential ash plumes at an altitude of 10-15 km.

 

Source: KVERT & VAAC Tokyo

Chirinkotan island in July 2016 / photo Y.Taran (a) - Google image (b) - the crater of Chirinkotan volcano in August 2015 / photo O.Chaplygin - Doc. Via Research Gate

Chirinkotan island in July 2016 / photo Y.Taran (a) - Google image (b) - the crater of Chirinkotan volcano in August 2015 / photo O.Chaplygin - Doc. Via Research Gate

In Nyiragongo, the eruption of May 22 released lava flows, which are covered with whitish deposits.

These deposits are used by the population of the Chiefdom of Bukumu and surroundings as a substitute for cooking salt.

A press release from the Governor of the Province of North Kivu has just been published banning the use and consumption of this "volcano salt".

After an analysis, its composition shows that it contains elements unfit for consumption: siliceous substances not soluble in water and traces of heavy metals and radioactive substances, toxic to the human body.

 

Source: Charles Balagizi / Goma Volcano Observatory

Nyiragongo - toxic deposits on the lava flows from the last eruption - photos © Charles Balagizi
Nyiragongo - toxic deposits on the lava flows from the last eruption - photos © Charles Balagizi

Nyiragongo - toxic deposits on the lava flows from the last eruption - photos © Charles Balagizi

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
Fukutoku Okanoba - plume detected by the Himawari satellite on 13.082021 at 09h00 - Doc. JMA

Fukutoku Okanoba - plume detected by the Himawari satellite on 13.082021 at 09h00 - Doc. JMA

According to the observation of the Himawari meteorological satellite, an eruption was observed from around 6:20 a.m. on August 13, 2021 at the submarine volcano Fukutoku Okanoba (about 50 km south of Iwo Jima)

A volcanic cloud spreads westward, without affecting any population.

Fukutoku Okanoba - volcanic ash advisory by JMA and VAAC Tokyo for August 13, 2021 - one click to enlargeFukutoku Okanoba - volcanic ash advisory by JMA and VAAC Tokyo for August 13, 2021 - one click to enlarge

Fukutoku Okanoba - volcanic ash advisory by JMA and VAAC Tokyo for August 13, 2021 - one click to enlarge

Fukutoku Okanoba - 3 D bathymetry / 1999 - Doc. courtesy of the Japan Coast Guard. via GVP

Fukutoku Okanoba - 3 D bathymetry / 1999 - Doc. courtesy of the Japan Coast Guard. via GVP

Fukutoku-Oka-no-ba is an underwater volcano located 5 km NE of the pyramidal island of Minami-Ioto. Water discoloration is frequently observed from the volcano and several ephemeral islands formed in the 20th century. The first of these formed Shin-Ioto ("New Sulfur Island") in 1904, and the most recent island was formed in 1986. The volcano is part of an elongated edifice with two high oriented topographic peaks. NNW-SSE, and is a trachyandesite volcano geochemically similar to Ioto.

The last eruption dates from February 3, 2010 to April 8, 2010 (GVP)

Sources: JMA, VAAC Tokyo and VAAC Darwin, Global Volcanism Program

Eruptive plume of Semisopochnoi - photo courtesy of Nora Rojek, R / V Tiglax 03.08.2021

Eruptive plume of Semisopochnoi - photo courtesy of Nora Rojek, R / V Tiglax 03.08.2021

More than 20 small explosions were detected in the North Cerberus crater in Semisopochnoi during the day of August 12. None of these were noted on satellite imagery, and a stable, low-level steam plume, possibly containing ash, was seen on clear web camera images this morning. Ash emissions from these explosions are likely similar to those of the past few days, but not always detected due to the low altitudes and cloud cover.

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

The volcanic alert remains with Watch, and the aviation code with Orange.

 

Source: AVO

Nevados de Chillán - 08.12.2021 / 11:46 UTC - Sernageomin webcam

Nevados de Chillán - 08.12.2021 / 11:46 UTC - Sernageomin webcam

Monitoring stations installed near the Nevados de Chillán volcanic complex, detected on August 12 two earthquakes associated with fluid dynamics inside the volcanic system (Long Period), respectively at 01:53 local time (05:53 UTC ) and at 03:28 local (07:28 UTC).

The Sernageomin reports two LP earthquakes on August 13 at 00:46 and 01:04 local time (04:46 and 05:04 UTC).

The technical alert remains at Amarilla

 

Source: Sernageomin

Fagradalsfjall - 11.08.2021 - lava flows in Meradalur - photo Alistair Hamill

Fagradalsfjall - 11.08.2021 - lava flows in Meradalur - photo Alistair Hamill

Fagradalsfjall - incandescence at the active crater and lava flows - 08.12.2021 / 03.42 a.m. webcam mbls

Fagradalsfjall - incandescence at the active crater and lava flows - 08.12.2021 / 03.42 a.m. webcam mbls

The eruption continues at Fagradalsfjall according to a now fluctuating pattern, as evidenced by the variations of the tremor.

Beautiful lava flows flow into Meradalur, first channeled then spreading out into deltas.

Fagradalsfjall - tremor at 13.08.2021 - Doc. Hraun.vedur

Fagradalsfjall - tremor at 13.08.2021 - Doc. Hraun.vedur

A mapping of the lava thicknesses was carried out by the Institute of Natural History and the collaboration of various organizations: it oscillates between 20 meters in the distal zones and a hundred meters near the active cone.

 

Sources: Institute of Natural History, Mbls, Hraun

Fagradalsfjall - thickness of the lava and position of the webcams - Doc. Institute of Natural History & al.

Fagradalsfjall - thickness of the lava and position of the webcams - Doc. Institute of Natural History & al.

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Publié le par Bernard Duyck
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Merapi - pyroclastic flow of 08.10.2021 / at 06:01 WIB - Doc. PVMBG Panguk - one click to enlarge

Merapi - pyroclastic flow of 08.10.2021 / at 06:01 WIB - Doc. PVMBG Panguk - one click to enlarge

Merapi - pyroclastic flow from 08.10.2021 / at 6:46 am WIB - webcam Deles PVMBG - one click to enlarge

Merapi - pyroclastic flow from 08.10.2021 / at 6:46 am WIB - webcam Deles PVMBG - one click to enlarge

The activity of Merapi / on Java was important on August 10 and 11, 2021.

The observatories report for August 10:

- Three pyroclastic flows, respectively at 05:58 WIB, 06:43 WIB, and 20:27 WIB, affecting distances of 2,500-3,000 meters and recorded on seismograms with an amplitude of 36-55 mm for 157-214 seconds.

- 385 avalanche earthquakes with an amplitude of 4 to 50 mm and a duration of 20 to 157 seconds; these avalanches were observed over a distance of 800-1,500 m. to the southwest.

- 21 blast / emission earthquakes, with an amplitude of 3 to 12 mm and a duration of 11.2 to 22.2 seconds.

- 1 low frequency earthquake

- 125 hybrid / multiphase earthquakes

- 33 shallow volcanic earthquakes, with an amplitude of 29 to 75 mm and an earthquake duration of 8.1 to 21 seconds.

- 6 distant tectonic earthquakes.

Merapi - seismicity at 11.08.2021 - Doc. BPPTKG

Merapi - seismicity at 11.08.2021 - Doc. BPPTKG

Merapi - thermal anomay - Sentinel-2 L1C SWIR image dated 11.08.202 - one click to enlarge

Merapi - thermal anomay - Sentinel-2 L1C SWIR image dated 11.08.202 - one click to enlarge

Merapi - 08.11.2021 / 12h - webcam PVMBG / Magma Indonesia

Merapi - 08.11.2021 / 12h - webcam PVMBG / Magma Indonesia

For August 11, 35 avalanches of incandescent lava were observed, with a sliding distance of 800 to 1,800 m to the southwest.

VAAC Darwin has issued an ash plume advisory reaching 4,300 m. altitude / alt. flight 140.

 

The activity level remains at 3 / siaga. The current potential danger consists of lava avalanches and hot clouds in the south-east-south-west sector for a maximum of 3 km to the Woro river and 5 km to the Gendol, Kuning rivers, Boyong, Bedog, Krasak, Bebeng and White. During this time, the ejection of volcanic material in the event of an explosive eruption can reach a radius of 3 km from the summit.

 

Sources: PVMBG, Magma Indonesia, BPPTKG, VAAC Darwin

Sheveluch - thermal anomalies at 08.12.2021 / 00h26 - image Sentinel-2 bands 4,3,2 & bands 12,11,8A and zoom in bands 12,11,8A - Doc. via Mounts Project
Sheveluch - thermal anomalies at 08.12.2021 / 00h26 - image Sentinel-2 bands 4,3,2 & bands 12,11,8A and zoom in bands 12,11,8A - Doc. via Mounts Project

Sheveluch - thermal anomalies at 08.12.2021 / 00h26 - image Sentinel-2 bands 4,3,2 & bands 12,11,8A and zoom in bands 12,11,8A - Doc. via Mounts Project

Strong gas and vapor emissions, with some amounts of ash continue at Sheveluch. A volcanic cloud rose to 4,500 - 5,000 m. asl., extending 51 km west- sid-west of the volcano.

KVERT mentions the collapse of the Dolphin lava block and a few small explosions.

The aviation code remains Orange, following the continuation of the “eruptive extrusive; other ash explosions can occur at more than 10 -15 km. asl. at any time and affect air traffic.

The VAAC Tokyo issued an ash advisory, and a plume at an estimated height of 5,200 meters above sea level, moving southwest.

 

Sources: KVERT, VAAC Tokyo, Mirova, Sentinel-2 / via Mounts project

Sheveluch - Sentinel-2 bands 12,11,8a & Modis thermalvolcanic activity - Doc. Mirova 08/12/2021 / 12:31 a.m.

Sheveluch - Sentinel-2 bands 12,11,8a & Modis thermalvolcanic activity - Doc. Mirova 08/12/2021 / 12:31 a.m.

Numerous small earthquakes were detected at a depth of 3-6 km and about 7 km southwest of the Korovin volcano. Earthquakes represent an increase over background seismic activity, but do not necessarily lead to an eruption. In response, the Alaska Volcano Observatory raised the Aviation Color Code and Alert Level of the Akta Volcanic Complex to YELLOW / Advisory.

The Alaska Volcano Observatory will continue to monitor the Atka complex for signs of volcanic activity. The area is monitored by local seismic and infrasound sensors, satellite data and regional lightning detection instruments.

Atka volcanic complex - recent earthquake hypocenters as of 11.08.2021 - Doc. Matt Loewen / AVO - USGS

Atka volcanic complex - recent earthquake hypocenters as of 11.08.2021 - Doc. Matt Loewen / AVO - USGS

The largest volcanic center in the Central Aleutians, Atka consists of a central shield and Pleistocene caldera with several post-caldera volcanoes.

A major dacitic explosive eruption accompanied the formation of the caldera about 500,000 to 300,000 years ago. The most important of the post-caldera stratovolcanoes are the Kliuchef and the Sarichef, both of which may have been active in historical time. The Sarichef has a symmetrical profile, but the less eroded Kliuchef is the source of most if not all of the historical eruptions. The Kliuchef may have been active on occasion at the same time as the Korovine volcano to the north. The hot springs and fumaroles are located on the slopes of the Kliuchef and in a glacial valley to the south-west of it.

 

Sources: AVO and Global Volcanism Program

Young vent on the NE flank of the Kliuchef- Photo Game McGimsey, 2004 (Alaska Volcano Observatory, U.S. Geological Survey). - in GVP

Young vent on the NE flank of the Kliuchef- Photo Game McGimsey, 2004 (Alaska Volcano Observatory, U.S. Geological Survey). - in GVP

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In Iceland, further measurements of the sitte of Fagradalsfjall were made on the afternoon of Sunday August 8, when aerial photographs were taken with the Hasselblad camera of the Institute of Natural History from the plane of the Fisfélag.

Fagradalsfjall eruption - parameters as of 08.08.2021 (lava field surface, lava flow emitted, discharge, geochemistry and released gases) - Doc. Jardvis

Fagradalsfjall eruption - parameters as of 08.08.2021 (lava field surface, lava flow emitted, discharge, geochemistry and released gases) - Doc. Jardvis

Terrestrial models were made based on these measurements and they were compared to older data.

Measurements show that the lava flow over the past 12 days has averaged 9.3 m³ / s.

When the measurements taken in July are compared, there is strong evidence that the flow was lower in the first half of July, 7-9 m³ / s, but then came a peak that lasted 8-10 days, where the flow could have reached 17-18 m³ / s on average. The uncertainty of these figures is considerable.

The lava emitted now has a volume of 119 million cubic meters and its area is 4.4 square kilometers.

No lava has flowed in Geldingadalur, Nátthaga and Syðri Meradalir for over a month. This situation has just changed: a small lava flow crossed the crater wall to the south on the night of August 9, to Geldingadalur.

Activity of Fagradalsfjall, Etna, Semisopochnoi and Sabancaya.
Fagradalsfjall - Gónhóll Cracks are marked in red on the map. The main crater is visible in the upper left corner. The aerial photography and the earth model are based on images from the Icelandic Institute of Natural History. Also based on aerial photographs from the Volcanology and Nature Conservation Group at the University of Iceland - photos of area cracks: Jarðsöguvinir - Friends of Historical Geology - one click to enlargeFagradalsfjall - Gónhóll Cracks are marked in red on the map. The main crater is visible in the upper left corner. The aerial photography and the earth model are based on images from the Icelandic Institute of Natural History. Also based on aerial photographs from the Volcanology and Nature Conservation Group at the University of Iceland - photos of area cracks: Jarðsöguvinir - Friends of Historical Geology - one click to enlarge

Fagradalsfjall - Gónhóll Cracks are marked in red on the map. The main crater is visible in the upper left corner. The aerial photography and the earth model are based on images from the Icelandic Institute of Natural History. Also based on aerial photographs from the Volcanology and Nature Conservation Group at the University of Iceland - photos of area cracks: Jarðsöguvinir - Friends of Historical Geology - one click to enlarge

New cracks are now visible in Gónhóll near the Fagradalsfjall volcanoes and they appear to have formed in the past two weeks. The area used to be a viewpoint frequented by volcanophiles, but is now surrounded by lava and accessible only by helicopter. The cracks are probably tensile cracks and line up north of Gónhóll towards the magma tunnel, southeast of the crater side.

 

Sources: University of Iceland, IMO, RUV, mbls

Etna - the south-eastern cone, the new summit of the volcano - photo by Boris Behncke on 07.22.2021 during a field visit

Etna - the south-eastern cone, the new summit of the volcano - photo by Boris Behncke on 07.22.2021 during a field visit

Etna today officially has a new peak. Thanks to the analysis of the Pléiades satellite images of July 13 and 25, 2021 by Tania Ganci, the exact height of the southeastern cone has been confirmed. The growth of the southeast crater / SEC, since December 2020, has caused it to overtake the other summit craters. It measures 3,357 meters ± 3 m.

Etna - two images from the Pléiades satellites (a: July 13, 2021 and b): July 25, 2021) and digital model of the surface resulting from the processing of satellite images, with the highest points of the craters of the South-East and North - East. - Doc. INGV OE

Etna - two images from the Pléiades satellites (a: July 13, 2021 and b): July 25, 2021) and digital model of the surface resulting from the processing of satellite images, with the highest points of the craters of the South-East and North - East. - Doc. INGV OE

Etna SEC - the growth of the south-eastern crater, illustrated by photos by Salvatore Lo Giudice (in 1983, 2016 and 2021) - via Etna News

Etna SEC - the growth of the south-eastern crater, illustrated by photos by Salvatore Lo Giudice (in 1983, 2016 and 2021) - via Etna News

On August 10 at 07:20 UTC, an explosive event took place in the northeast crater of Etna, generating an ash cloud that reached a height of about 6,000 m. altitude, and which then spread to the southeast.

This explosion was followed by further low emissions of ash and steam; currently the phenomenon is decreasing.
From 07:19 UTC, a seismic sequence lasting about 1 minute was recorded, consisting of about 5 low frequency events of moderate energy, attributable to the explosive activity of the northeast crater. low values ​​and a subsequent return to low values.
Regarding infrasonic activity, no significant variation is recorded, except for a low energy infrasonic signal associated with the reported explosive activity.

The INGV reports at 9:39 UTC that the emission of volcanic ash from the northeast crater continues, with a fluctuating intensity, feeding an eruptive cloud directed towards the southeast. The cloud reaches a height of between 5,000 and 6,000 m above sea level.
The mean amplitude of the volcanic tremor shows no significant change. The source centroid is located in the area of ​​the Voragine and Northeast craters at a depth of approximately 2800 m above sea level. No significant changes in infrasound activity.

 

Source: INGV OE, Etna News / Salvatore Lo Giudice, Boris Benhcke

Etna - explosion at NE crater on 08.10.2021 / 07:20 UTC; the plume rose to 6000 m asl. - photo Etna News

Etna - explosion at NE crater on 08.10.2021 / 07:20 UTC; the plume rose to 6000 m asl. - photo Etna News

Etna summit craters - to note: the plume of the NEC and the lava flows of the activity of the SEC still hot - images Sentinel-2 L1C bands 12,11,4 and SWIR from 08.10.2021 - one click to enlarge
Etna summit craters - to note: the plume of the NEC and the lava flows of the activity of the SEC still hot - images Sentinel-2 L1C bands 12,11,4 and SWIR from 08.10.2021 - one click to enlarge

Etna summit craters - to note: the plume of the NEC and the lava flows of the activity of the SEC still hot - images Sentinel-2 L1C bands 12,11,4 and SWIR from 08.10.2021 - one click to enlarge

Ten separate explosions have been detected from the North Cerberus crater at Semisopochnoi over the past day, and a small, low-level plume has occasionally been noted on satellite imagery drifting east. Small ash and vapor emissions were detected in clear images from web cameras.

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

The Semisopochnoi is monitored by local seismic and infrasound sensors, satellite data, web cameras, and remote infrasound and lightning networks.

The volcanic alert is Watch, and the aviation code is Orange.

 

Source: AVO

Semisopochnoi - eruptive plume of 03.08.2021- photo courtesy Nora Rojek, R / V Tiglax via AVO

Semisopochnoi - eruptive plume of 03.08.2021- photo courtesy Nora Rojek, R / V Tiglax via AVO

During the week of August 2-8, Sabancaya maintained moderate levels of activity, averaging 51 explosions per day, accompanied by plumes of gas and ash reaching 2,300 meters above the summit.

During this period, IGPeru detected and analyzed 1,229 volcanic earthquakes associated with the circulation of magmatic fluids, and VT earthquakes, linked to rock fracturing, from M2.4 to 3.5, located mainly in the north and northwest of the volcano.

The deformation does not show any significant anomaly. Five thermal anomalies were identified by Mirova, with a max. of VRP 7MW.

The level of the volcanic alert remains in Naranja, with a prohibited zone of 12 km in radius around the crater.

 

Source: I.G. Peru

Sabancaya - activity between 02 and 08.08.2021 - Doc. I.G. Peru

Sabancaya - activity between 02 and 08.08.2021 - Doc. I.G. Peru

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
Etna SEC - morning activity from 08.09.2021 / 05.45 a.m. - photo Gio Giusa

Etna SEC - morning activity from 08.09.2021 / 05.45 a.m. - photo Gio Giusa

From the analysis of Etna's video surveillance network, it is noted that a weak emission of lava continues from the east and south-east base of the SE crater. The lava flows remain confined to an altitude of about 2900 m.
The last ash emission from the SE crater occurred around 13:30 UTC.


During the morning of August 9, the average amplitude of the volcanic tremor showed significant and sudden fluctuations between medium-low and medium-high values, linked to the appearance of low-frequency transient phenomena associated with the activity. explosive at the level of the SE crater and whose trace infrasound is also clearly visible. At 20h UTC, the amplitude shows average values ​​and the centroid of the sources is located in the area of ​​the Voragine crater at an altitude of about 2.700 m above sea level. Regarding infrasound activity, except for the aforementioned phases of rapid increase in the rate of occurrence in the amplitude of events at the SE crater, it remained at a medium-low level with sources in the area. from the Bocca Nuova crater. The infrasonic activity is currently low.
Since the last update, no significant changes have been observed in the time series of soil deformation monitoring stations.

 

Source: INGV OE

Etna - variations of the tremor at 08.10.2021 / 07h. - Doc. INGV OE

Etna - variations of the tremor at 08.10.2021 / 07h. - Doc. INGV OE

The surface activity in the Copahue volcano, province of Neuquén on the border of Chile and Argentina, presents this August 9, 2021 water vapor and gas emissions. In the evening, incandescence is visible in the El Agrio crater, as are pulsatile gas emissions.

On 08/09/21, TROPOMI detected a strong SO2 signal at a distance of 5.9 km from the Copahue, with 68.25 DU of SO2 at an altitude of about 2 km. Estimated mass within a radius of 300 km: 15.3 kts.

The Copahue Volcano presents a seismic signal at low energy levels. The Sernageomin speaks of an eruptive work which respects the NORMAL parameters.

Copahue, seen from Caviahue - degassing from 08.09.2021 in the morning - photo Valentina Sepulveda

Copahue, seen from Caviahue - degassing from 08.09.2021 in the morning - photo Valentina Sepulveda

Copahue - night glow on 09.08.2021 - photo via Emergencias Chile

Copahue - night glow on 09.08.2021 - photo via Emergencias Chile

Copahue - 08.09.2021 - strong SO2 signal at a distance of 5.9 km from the Copahue, with 68.25 DU of SO2 at an altitude of about 2 km - Doc. Sentinel-5P Tropomi

Copahue - 08.09.2021 - strong SO2 signal at a distance of 5.9 km from the Copahue, with 68.25 DU of SO2 at an altitude of about 2 km - Doc. Sentinel-5P Tropomi

During the month of July, Sernageomi recorded 68 VT earthquakes, associated with rock failures; the largest was M 2.5, located 6.5 km northeast of the active crater and at a depth of 4.8 km.

Two LP earthquakes, related to the dynamics of internal fluids were observed.

During the month of July, vertical degassing columns were spotted reaching max. 540 meters above the crater, as well as occasional nocturnal incandescence.

The technical alert is green, with the designation of an assignment zone of 500 meters in radius around the crater.

Nevados de Chillan - Webcam Sernageomin 08.09.2021

 

In Chile, the Sernageomin keeps the Amarilla alert for the Nevados de Chillan, the Hudson and the Laguna del Maule complex.

 

Sources: Sernageomin & Tropomi

Chirinkotan - degassing - Source archives plate-tectonic.narod.ru / via KVERT

Chirinkotan - degassing - Source archives plate-tectonic.narod.ru / via KVERT

A moderate explosive event from Chirinkotan Volcano (Chirinkotan Island), northern Kurils, occurred at 08:15 UTC on August 09. A 13x10 km ash cloud drifts at an altitude of 2300-2500 m. , about 26 km south-southeast of the volcano.

The moderate eruptive activity of the volcano continues. Ash explosions up to 10-15 km (32,800-49,200 feet) altitude. could arise at any time. Current activity could affect international and low-flying aircraft.

The last explosive eruption of the volcano dates back to 2013-2015; explosions sent ash up to 4 km altitude.

 

Source: KVERT

Fagradalsfjall - new vent - webcam mbls 09.08.2021 / 11:18

Fagradalsfjall - new vent - webcam mbls 09.08.2021 / 11:18

A new vent / also referred as "a hole" opened at the edge of the active Icelandic / Fagradalsfjall eruption crater on August 9 at 10:06 am local time, and both are now producing lava from the same source. Volcanic tremors at the site began to increase around 3:00 a.m. this morning, continuing the eruption's fluctuating activity pattern. Note that this new vent is no longer productive at 2:40 p.m. local time.

Fagradalsfjall - evening activity from 08.09.2021 / 10:09 p.m. - mblx webcam

Fagradalsfjall - evening activity from 08.09.2021 / 10:09 p.m. - mblx webcam

Fagradalsfjall - tremor on 10.08.2021 - Doc. Hraun.vedur

Fagradalsfjall - tremor on 10.08.2021 - Doc. Hraun.vedur

The nocturnal activity was important; many tongues of lava have been fed and a torrent of lava is pouring down into Meradalur, while some of the lava flows into Geldingadalur. The flow remains high, with an average of 11-12 m³ / second according to recent measurements

Volcanologists Þorvaldur Þórðarson and Ármann Höskuldsson were at the eruption site yesterday to take action: “ This is a very unique eruption that is calmly rising to the surface and nothing seems to affect it. He appropriates the land as he pleases ".

 

Sources: RUV, mbls and Iceland Review

Reventador / Cámara Copete - Plume of gas and ash. 08/08/2015 11:13 PM UTC - IGEPN webcam

Reventador / Cámara Copete - Plume of gas and ash. 08/08/2015 11:13 PM UTC - IGEPN webcam

Reventador - 08.09.2021 - IGEPN time lapse (99% of the time, the webcams were inoperative due to the clouds)

Several steam emissions were observed in Reventador, Ecuador, which reached up to 1,200 meters above the crater in a north-westerly and westerly direction. The Washington VAAC reported ash emission up to 988 meters above the summit to the west.

Seismicity is characterized over the last 24 hours by 34 explosion earthquakes, 42 LP earthquakes and 3 tremor period.
MIROVA has recorded 1 low thermal anomaly in the last 24 hours.
During the night, an incandescence was observed at the level of the crater. During the morning of August 9, the weather remained very cloudy.

 

Source: IGEPN

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 Etna SEC - 08/09/2021 - 03:32 local - photo courtesy of © Pippo Scarpinati

 Etna SEC - 08/09/2021 - 03:32 local - photo courtesy of © Pippo Scarpinati

After an increase in the Etna tremor in average values ​​on August 7 in the evening, it did not really drop.

On the contrary, it gradually rose on the evening of August 8 to produce at the level of the southeast crater beautiful bubbles exploding with "boati", lava fountaining, an impressive plume, and a lava flow on early hours of August 9.

The climax ended around 6 a.m. on August 9.

More unusual, a new mouth opened at the eastern base of the southeast crater, at 07:41 local time, with emission of volcanic sand towards the Valle del Bove (communication from Pippo Scarpinati).

 

Sources: Pippo scarpinati, Gio Giusa and Boris Behncke

Etna SEC - Explosions and lava flow on 08/09/2021 - 03.35 am loc - photo courtesy of © Pippo Scarpinati

Etna SEC - Explosions and lava flow on 08/09/2021 - 03.35 am loc - photo courtesy of © Pippo Scarpinati

Etna SEC -Lava fountain and lava flow 08/09/2021 - 05h34 loc - photo courtesy of © Pippo Scarpinati

Etna SEC -Lava fountain and lava flow 08/09/2021 - 05h34 loc - photo courtesy of © Pippo Scarpinati

Etna SEC -Fountain and lava flow 08/09/.2021 - 05h51 loc - photo courtesy of © Pippo Scarpinati

Etna SEC -Fountain and lava flow 08/09/.2021 - 05h51 loc - photo courtesy of © Pippo Scarpinati

Etna SEC - final phase of the climax 08/09/2021 - 06:07 loc - photo courtesy of © Pippo Scarpinati

Etna SEC - final phase of the climax 08/09/2021 - 06:07 loc - photo courtesy of © Pippo Scarpinati

Etna - variations of the tremor at 08/09/2021 / 07h - Doc. INGV OE

Etna - variations of the tremor at 08/09/2021 / 07h - Doc. INGV OE

Etna - 08/09/2021 07:41 loc.- opening of a new mouth at the base of the SE crater and emission towards the Valle del bove - photo courtesy of © Pippo Scarpinati

Etna - 08/09/2021 07:41 loc.- opening of a new mouth at the base of the SE crater and emission towards the Valle del bove - photo courtesy of © Pippo Scarpinati

During the last 24 hours, thanks to the monitoring systems of the Popocatépetl volcano, 30 exhalations have been identified, some of them accompanied by water vapor, volcanic gases and ash. In addition, 789 minutes of tremor were recorded, and an explosion at 2:58 a.m., due to weather conditions, its height and direction could not be determined.

On August 7 at 7:37 p.m., a volcano-tectonic earthquake with a calculated magnitude of 1.6 was recorded.

During the morning and at the time of this report, the emission of volcanic gases with a westerly direction is observed

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 mudslides and waste.

The Popocatépetl Volcanic Warning Semaphore is in YELLOW PHASE 2.

 

Sources: Cenapred & webcams from Mexico

Popocatépetl - exhalation on 08/07/2021 / 1:28 p.m. - WebcamsdeMexico / Cenapred

Popocatépetl - exhalation on 08/07/2021 / 1:28 p.m. - WebcamsdeMexico / Cenapred

Popocatépetl - 24 hour activity summary. to 08.08.2021 - Cenapred

Popocatépetl - 24 hour activity summary. to 08.08.2021 - Cenapred

Volcano activity continues at moderately high levels, with moderate to strong explosions at the summit crater of On-take (Otake) NE of Suwanosejima.
The volcano sent pyroclastic material to about 1,700 m. above the crater. The volcanic ash is scattered in various directions, particularly to the west.
Explosions generated pyroclastic bombs and blocks ejected up to 500 meters from the crater.
An almost constant glow is visible from the summit crater at night detected by surveillance cameras.
Short-term electronic tilt monitoring recorded ground deformation on the western flank on July 15.
The JMA indicates that the ballistic impacts of the volcanic bombs could affect an area approximately 1 km away from the main crater.

 

Source: JMA report

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 Great Sitkin lava dome - photo 06.08.2021 Alexander Chamberlin via AVO

 Great Sitkin lava dome - photo 06.08.2021 Alexander Chamberlin via AVO

Incandescence was visible over the growing lava dome of Great Sitkin on Friday evening (August 6) around 10:30 p.m., along with a robust plume of steam.

High surface temperatures were seen on a satellite image, but all other satellite and webcam views of the volcano over the past day have been obscured by clouds. The high surface temperatures are the result of an effusion of lava in the summit crater.

The dome was measured, using satellite radar images, over 230 m in diameter as of Thursday, August 5.

 

Source: AVO

Reykjanes peninsula - Deployment of a coastguard vessel for verification off Krisuvik on 07.08.2021 - photo Visir

Reykjanes peninsula - Deployment of a coastguard vessel for verification off Krisuvik on 07.08.2021 - photo Visir

In the Reykjanes Peninsula, the Coast Guard received a report shortly after 8 p.m. on August 7 from a passerby in Selvogsvita who had seen plumes of dark gray smoke at sea. Although nothing was noticed on the aircraft. IMO control vessel, the coastguard vessel Þór made a sortie west of Krýsuvíkurberg to confirm or deny the existence of signs of an underwater eruption. The Coast Guard information officer said no smoke was visible ...

The eruption continues on earth. After a sudden drop in the tremor during the day of August 7, it rose again in the early evening, and the night was marked by incandescence and lava flows.

 

Sources: mbls webcam and Visir

Fagradalsfjall - strong variations in activity on 08/07/2021 - mbls webcam at 07:53 am and 08:08 am
Fagradalsfjall - strong variations in activity on 08/07/2021 - mbls webcam at 07:53 am and 08:08 am

Fagradalsfjall - strong variations in activity on 08/07/2021 - mbls webcam at 07:53 am and 08:08 am

Fagradalsfjall - variations of the tremor at 08.08.2021 - Doc. Hraun.vedur.is

Fagradalsfjall - variations of the tremor at 08.08.2021 - Doc. Hraun.vedur.is

Fagradalsfjall - still active on 08.08.2021 / 02h20 - webcam mbls

Fagradalsfjall - still active on 08.08.2021 / 02h20 - webcam mbls

Lava tornado in Meradalur on 08/06/2021 - video Hugi Podarson

The seismic activity at La Soufrière in St Vincent has remained weak since the tremor associated with the explosion and the ash removal of April 22. In the past 24 hours, only a few small earthquakes have been recorded.
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.
Sulfur dioxide flow measurements at La Soufrière were taken by boat off the west coast on August 3, with help from the coast guard. Several crossings were made and gave an average SO2 flow of 207 tonnes per day.

The volcano is at the Orange alert level.
There is a small, but not insignificant, possibility that magmatic activity will resume in the event of an influx of new magma from the depths.

 

Source: UWI - SRC 07.08.2021 / 1pm

Soufriere of St. Vincent - Doc. UWI - Aerial view of the summit of La Soufrière. Mustique Airways 07.08.2021

Soufriere of St. Vincent - Doc. UWI - Aerial view of the summit of La Soufrière. Mustique Airways 07.08.2021

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 Pavlof - ash emission on 05.08.2021 - Code Orange - Doc. AVO

 Pavlof - ash emission on 05.08.2021 - Code Orange - Doc. AVO

Unrest continues at Pavlof volcano and minor ash emissions just above the top of the volcano were observed on August 5, 2021. Seismic tremors and small explosions were detected by local seismic and infrasound instruments. The ash emissions observed were of limited extent and probably only produced local fallout on the southeast flank of the volcano.

The level of restlessness at Pavlof can change rapidly and progression to rash activity may occur with little or no warning.

Ash emissions indicate an active eruption in progress, so the Alaska Volcano Observatory is raising the Aviation Color Code and Alert Level to ORANGE / WATCH.

 

Note that in the area under the responsibility of the AVO, three volcanoes are on Watch / orange alert : the Great Sitkin, the Pavlof and the Semisopochnoi.

 

Source: AVO / Alaska Volcano Observatory

Fagradslasfjall - activity at the cone and lava flows on 08.062021 / 01h52 - webcam_langihryggur / RUV

Fagradslasfjall - activity at the cone and lava flows on 08.062021 / 01h52 - webcam_langihryggur / RUV

Fagradalsfjall - activity continued all day - webcam langihryggur NV / Almannavarnir 08.06.2021 / 22h50

Fagradalsfjall - activity continued all day - webcam langihryggur NV / Almannavarnir 08.06.2021 / 22h50

In Fagradalsfjall, the activity was maintained all day yesterday, with feeding of the lava flows in several arms; ke trémor testifies to a new stability.

 

Sources: webcams & Hraun.vedur

Fagradalsfjall - tremor at 07.08.2021 - Doc. Hraun.vedur

Fagradalsfjall - tremor at 07.08.2021 - Doc. Hraun.vedur

The volcanic activity of Merapi remains quite high, during the week of July 30 and August 5, 2021, in the form of effusive eruption activity.

The PVMBG provides information over the period of 7 pyroclastic avalanche flows in the southwest with a maximum glide distance of 2,000 m. Boulder collapses were observed 84 times to the southwest with a maximum slide distance of 2,000 m.

Based on the morphological analysis of the Deles5, Tunggularum, Ngepos and Babadan2 camera stations, the southwest lava dome increased by about 3 m. with a volume of 1,895,000 m³. The volume of the central dome is relatively fixed.

The deformation of Mount Merapi, which was monitored using EDM this week, showed a distance shortening rate of 12 cm / day.

The activity level remains at level 3 / Siaga. The current potential danger consists of lava avalanches and pyroclastic flows in the south-east-south-west 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; and the ejection of volcanic material in the event of an explosive eruption can reach a radius of 3 km from the summit.

Aviation code on 06.08.2021: Orange (VAAC Darwin)

 

Sources: PVMBG, Magma Indonesia, BPPTKG, VAAC Darwin

Merapi - weekly report on summit morphology - Doc. BPPTKG 05.08.2021 - one click to enlarge

Merapi - weekly report on summit morphology - Doc. BPPTKG 05.08.2021 - one click to enlarge

Merapi - seismicity at 05.08.2021 - Doc. PVMBG Magma Indonesia

Merapi - seismicity at 05.08.2021 - Doc. PVMBG Magma Indonesia

According to a news source, residents of Savo in the Solomon Islands reported an increase in seismicity to authorities on July 28.

Two days later, a team from the Geological Survey Division (GSD) and the National Disaster Management Office (NDMO) investigated the volcano. They saw steam and gas emissions rising from an area of ​​the crater, possibly indicating an active crack, and questioned residents. The GSD briefed the National Disaster Operations Committee and other authorities on July 31, confirming the increase in seismicity and prompting a preparedness response.

Response actions included the continued surveillance of the island, the deployment of technical teams and the issuance of safety messages on the volcanoes to inform residents of the island as well as the surrounding areas.

Source: SBM Online / GVP

Savo island - Sentinel-2 bands image 12,11,4 from 06.08.2021 - one click to enlarge the satellite images
Savo island - Sentinel-2 bands image 12,11,4 from 06.08.2021 - one click to enlarge the satellite images

Savo island - Sentinel-2 bands image 12,11,4 from 06.08.2021 - one click to enlarge the satellite images

The 6 x 7 km island of Savo consists of a wooded, andesitic to dacitic stratovolcano, with a shallow, elliptical, 1 x 1.5 km wide summit crater. Lava domes of historic age are located on the crater floor and its NE rim, and older domes are found on the flanks of the volcano.

Pyroclastic flows and mudslides descended the valleys from the summit crater to form fans of debris along the coast. The thermal zones located in the summit crater, the southern flanks to the southeastern flanks and offshore include areas of smoking soil, fumaroles, small geysers and hot springs.

The last eruption of VEI 3 dates from 1835 to 1847, according to the GVP

 

Source: Global Volcanism Program

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