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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
Suwanosejima - explosion at 9:10 a.m. on 08/27/2021 - JMA webcams / 9:13 a.m. - 9:16 a.m.

Suwanosejima - explosion at 9:10 a.m. on 08/27/2021 - JMA webcams / 9:13 a.m. - 9:16 a.m.

On Suwanosejima, volcanic activity continues at high levels.
Moderate to strong vulcanian explosions are again in progress at the crater at the top of On-take volcano NE.

Similar activity occurred in early August as a series of violent eruptions sent ash up to 3 km above sea level.
A spectacular ash plume rising to 2,600 m. above the summit could be observed around 9:10 a.m. local time today and dispersed in a northwesterly direction, in accordance with the ash scattering advisory issued by VAAC Tokyo.
Explosions generated pyroclastic bombs and blocks ejected up to 400 meters from the crater.
An almost constant glow is visible at the summit at night, detected by surveillance cameras.

 

Sources: JMA & VAAC Tokyo

Nyamuragira - image Sentinel-2 bands 12,11,4 from 25.08.2021

Nyamuragira - image Sentinel-2 bands 12,11,4 from 25.08.2021

Nyamuragira - image Sentinel-2 bands 12,11,8A from 25.08.2021

Nyamuragira - image Sentinel-2 bands 12,11,8A from 25.08.2021

Eruptive activity was detected in the Nyamulagira crater by the Sentinel-1 and Sentinel-2 probes on August 25, 2021.

Thermal anomalies have been observed by Mirova more regularly since August 22, 2021.

 

Sources: Charles Balagizi / GVO, Sentinel and Mirova.

Nyamuragira - thermal anomalies at 26-27.08.2021 - Doc. Mirova - one click to enlargeNyamuragira - thermal anomalies at 26-27.08.2021 - Doc. Mirova - one click to enlarge

Nyamuragira - thermal anomalies at 26-27.08.2021 - Doc. Mirova - one click to enlarge

The Ol Doinyo Lengai crater in Tanzania is busy filling up.

Pictures of sat. Sentinel-2 shows hot spots in the crater, while Mirova reports thermal anomalies on August 24 and 25 from VRP between 13 and 81 MW.

These satellite images depend on both activity and the absence of cloud cover, a factor enabling thermal anomalies to be measured.

 

Sources: Sentinel-2 and Mirova

Ol Doinyo Lengai - images Sentinel-2 bands 12,11,4 (green dominant) and 12,11 8A bands (blue dominant) and zoom on the hot spots in the crater / Sentinel-2 bands 12,11,8A - one click to enlarge
Ol Doinyo Lengai - images Sentinel-2 bands 12,11,4 (green dominant) and 12,11 8A bands (blue dominant) and zoom on the hot spots in the crater / Sentinel-2 bands 12,11,8A - one click to enlargeOl Doinyo Lengai - images Sentinel-2 bands 12,11,4 (green dominant) and 12,11 8A bands (blue dominant) and zoom on the hot spots in the crater / Sentinel-2 bands 12,11,8A - one click to enlarge

Ol Doinyo Lengai - images Sentinel-2 bands 12,11,4 (green dominant) and 12,11 8A bands (blue dominant) and zoom on the hot spots in the crater / Sentinel-2 bands 12,11,8A - one click to enlarge

Ol Doinyo Lengai - anomalies thermiques au 26.08.2021 - Doc. Mirova / Sentinel-2
Ol Doinyo Lengai - anomalies thermiques au 26.08.2021 - Doc. Mirova / Sentinel-2

Ol Doinyo Lengai - anomalies thermiques au 26.08.2021 - Doc. Mirova / Sentinel-2

Lava from the Fagradalsfjall eruption cascades again into the Nátthaga Valley.

Þorvaldur Þórðarson, volcanologist on site says that " the lava flow is of importance ... a breach has opened in the crater and the lava flows on August 26 at Syðri-Meradalur and from there to Nátthaga, where it cascades, very fluid ... The front edge of the lava field, which is now moving over Nátthagi, covers almost the entire valley. In other words, it extends between the slopes ", Þorvaldur explains.

The eruption continues with an alternation of active phases and pauses, as illustrated by the outline of the eruptive tremor.

Considering the unchanged flow, it will probably take about two weeks to fill Nátthaga. Then it will take some time to fill the square on Suðurstrandavegur.

 

Sources: mbls, RUV, Iceland Review

 Fagradalsfjall eruption - 26.08.2021 -  lava overflow at the active crater and distribution in several arms - photo mbl.is / Árni Sæberg / Twitter

Fagradalsfjall eruption - 26.08.2021 - lava overflow at the active crater and distribution in several arms - photo mbl.is / Árni Sæberg / Twitter

Fagradalsfjall - the lava cascading in the Nátthaga valley - 26.08.2021 / 11:33  - Screen-Shot video Daníel Páll Jónasson

Fagradalsfjall - the lava cascading in the Nátthaga valley - 26.08.2021 / 11:33 - Screen-Shot video Daníel Páll Jónasson

Fagradalsfjall - tremor at 27.08.2021 - Doc. Hraun.vedur

Fagradalsfjall - tremor at 27.08.2021 - Doc. Hraun.vedur

An ash emission was observed at Nevado del Ruiz on August 26 at around 8 a.m. thanks to webcams. The column of gas and ash reached a maximum height of 490 m., With a direction of dispersion to the west - north-west. The fall of ashes in the communes located in the direction of the wind is not to be excluded.

The Nevado del Ruiz volcano continues in the yellow activity level (or III).

 

Source : SGC

 Nevado del Ruiz - Temblor Red Circle Alerta Sismica @ ElLuchin1 25.08.2021 - Twitter

Nevado del Ruiz - Temblor Red Circle Alerta Sismica @ ElLuchin1 25.08.2021 - Twitter

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
 Kilauea summit - Doc. HVO-USGS photo by M. Patrick 22.07.2021 - one click to enlarge

Kilauea summit - Doc. HVO-USGS photo by M. Patrick 22.07.2021 - one click to enlarge

Kilauea - seismic swarm of 08/24/2021 / 6:36 p.m. - magmatic dyke intrusion in the southern caldera -Doc. HVO-USGS - one click to enlarge

Kilauea - seismic swarm of 08/24/2021 / 6:36 p.m. - magmatic dyke intrusion in the southern caldera -Doc. HVO-USGS - one click to enlarge

The US Geological Survey's Hawaiian Volcanoes Observatory has detected an increase in seismic activity beneath the southern portion of the Kīlauea Summit Caldera in Hawaii Volcanoes National Park.

Activity began around 4:30 p.m. HST on August 23 and continued through the night and into the early morning hours of August 24, 2021. The swarm was accompanied by increased ground deformation recorded by the Sandhill inclinometer, just west of the site of the seismic swarm. The same incline increase was also recorded by the inclinometer near Uēkahuna Bluff and the site of the former HVO building.

At around 1:30 am on August 24, the earthquake swarm intensified in this region; this activity may indicate a magma intrusion occurring 1–2 km (0.6–1.2 miles) below the southern caldera.
More than 140 earthquakes were recorded at 4.30 a.m. on August 24; the largest recorded earthquake was magnitude 3.3 with the majority of earthquakes below magnitude 1. Small earthquakes continue at a rate of at least 10 detected earthquakes per hour.

 

Seismicity and ground deformation indicate a small dyke intrusion may occur 1-2 km (0.6-1 .2 mi) below the southern caldera.

The Volcanic Alert Level / Aviation Color Code for Kīlauea has been raised from Advisory / Yellow to Watch / Orange due to this activity.

An eruption is possible (or maybe just an intrusion) anytime within hours or days, likely in the caldera or maybe even in the southwest fault.

 

Source: HVO-USGS

Fukutoku-Okanoba - Doc. Axelspace 08/14/2021, via Shérine France - one click to enlarge

Fukutoku-Okanoba - Doc. Axelspace 08/14/2021, via Shérine France - one click to enlarge

Thanks to JX PRESS which collaborated with the space company "Axel Space", which develops and operates artificial satellites in-house, satellite images of the submarine volcano Fukutoku Okanoba in the Ogasawara islands could be taken, confirming the eruption on April 13, 2021. Filming was carried out for 4 consecutive days from the 14 immediately after the eruption.

Floating substances such as pumice stones that could be seen around the eruption point have gradually faded and on the 16th the appearance of the "Niijima in brackets" is clearly visible. According to the Japanese Coast Guard, Niijima's size is about 1 km in diameter at 16, and the range of the floating material has reached about 100 km in the west-northwest (maximum width of about 13 km ). (JX PRESS / FASTALERT)

 

The images reveal the morphological modifications of Niijima as soon as it appears: erosion does its work, and if the eruption remains at this stage, the sustainability of the new island is by no means guaranteed.

 

Source: News Digest- Jx Presse / Axel Space - https://newsdigest.jp/news/9464c248-7bd5-4299-b092-8d1c90c4b819 - via Shérine France

Fukutoku-Okanoba - zoom in the Axei Space images from 08/14/2021 (top) and 08/17/2021 (bottom) showing Niijima's morphology changes
Fukutoku-Okanoba - zoom in the Axei Space images from 08/14/2021 (top) and 08/17/2021 (bottom) showing Niijima's morphology changes

Fukutoku-Okanoba - zoom in the Axei Space images from 08/14/2021 (top) and 08/17/2021 (bottom) showing Niijima's morphology changes

Over the past 24 hours, several ash emissions have been observed at the Reventador in a westerly, southwest, and southerly direction, with plume heights approaching 600 and 1,000 meters above crater level.

The VAAC Washington reported 4 alerts of emissions observed by satellites; the direction of these emissions oscillated from west to southwest and the heights did not exceed 1,400 meters above the level of the crater.

FIRMS reported 14 thermal alerts to the Reventador in the last 24 hours. MIROVA reported 2 low thermal alerts and 1 moderate thermal alert to Reventador in the past 24 hours.

During the same period, the volcano sometimes became cloudy. At night, an incandescence was observed in the crater and the rolling of boulders along the southern flank of the volcano up to 500 meters below the level of the crater.

Seismicity is expressed in:
- 99 explosio earthquakes
- 67 LP earthquakes
- 14 episodes of emission tremor (TREMI)
- 2 episodes of harmonic tremor (TRARM)


Source: IGEPN - Daily information 23.08 - 24.08.2021 / 11h-11h

Reventador - Sentinel-2 bands 12,11,8A & Modis thermal volcanic activity 08/24.2021 / 3:43 pm - Doc. Mirova

Reventador - Sentinel-2 bands 12,11,8A & Modis thermal volcanic activity 08/24.2021 / 3:43 pm - Doc. Mirova

Reventador - 08.24.2021 / Volcano Time-Lapse video / IGEPN images

A moderate eruptive activity continues at Ebeko volcano.

According to visual data from volcanologists in Severo-Kurilsk, an explosion sent ash on August 24 up to 3,700 m. altitude; an ash cloud drifts south-east of the volcano for 10 km.

Moderate eruptive activity of the volcano continues. Ash explosions up to 6 km (19,700 ft) above sea level could occur at any time. The current activity could affect low-flying planes and Severo-Kurilsk airport.

The aviation code remains with Orange.

 

Source: KVERT

Ebeko - explosive episode of 04.07.2021 / photo M. Shchekleina. M.V. Lomonosov MGU - KVERT

Ebeko - explosive episode of 04.07.2021 / photo M. Shchekleina. M.V. Lomonosov MGU - KVERT

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
 Sabancaya - activity between August 16 and 22, 2021 - photo I.G. Peru

Sabancaya - activity between August 16 and 22, 2021 - photo I.G. Peru

Between August 16 and 22, the eruptive activity of Sabancaya remained at moderate levels, with an average of 33 daily explosions, accompanied by plumes of ash and gas reaching up to 2,900 m. above the summit.

During the week, 822 earthquakes of volcanic origin associated with the circulation of internal magmatic fluids were detected and analyzed. VT earthquakes, linked to rock fracturing, mainly concern a large northern sector, with magnitudes from 2.5 to 3.3.

No significant deformation anomalies. Six thermal anomalies, of VRP max. of 9 MW, are associated with the presence of a lava body in the crater.

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

 

Source: I.G. Peru

Lokon - Tompaluan crater - photo archives 2009 / Thorsten Boeckel

Lokon - Tompaluan crater - photo archives 2009 / Thorsten Boeckel

The BPBD of Tomohon, on Sulawesi, gave the order to close the climbing activities of the Lokon volcano, in activity level 2 / waspada.

The PVMBG reminds the public and tourists not to approach or carry out activities within a radius of 1.5 km radius of the Tompaluan crater, following an increase in surface earthquakes.

Yesterday, a light white plume 25-50 meters high surmounted the active crater.

The seismicity of August 23 was characterized by:

- 4 blast / emission earthquakes, with an amplitude of 9 to 41 mm and an earthquake duration of 10 to 100 seconds.
- 7 shallow volcanic earthquakes, with an amplitude of 3 to 14 mm and an earthquake duration of 3 to 7 seconds.
- 1 deep volcanic earthquake with an amplitude of 14 mm, S-P 0.75 seconds and a duration of 6.5 seconds.
- 3 distant tectonic earthquakes.

 The last eruption dates back to 30.08-28.09.2015 (GVP)

 

Sources: PVMBG, Magma Indonesia and Tempo

Lokon - éruption de fin août 2015 - photo archives Jakarta globe

Lokon - éruption de fin août 2015 - photo archives Jakarta globe

At approximately 7:40 a.m. on Sunday, August 22, 2021, a period of minor ash emission was observed from the active ventilation zone of Whakaari / White Island.

According to the webcam observations, the ash emission persisted for about two minutes. It was not visible in the footage from Whakatane's camera. Based on the short duration of the activity, it is unlikely that it produced a plume large enough to create ashfall even on the island.

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

Satellite radar data continues to show small amounts of ground deformation around the active vent and the lake area.

Whakaari / White island - 08/24.2021 / 1:30 p.m. loc. - GeoNet photo

Whakaari / White island - 08/24.2021 / 1:30 p.m. loc. - GeoNet photo

These observations do not change recent interpretations that a new shallow level magma intrusion has occurred since June 2021. The ash emission observed on Sunday may be related to the shallow magma under the active vents, but its short duration suggests that unstable material falling into the vent, then fragmented and then ejected by gas pressure, may be a more plausible explanation.

The volcanic alert level remains at 2 and the aviation code at yellow.

 

Sources: GeoNet

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Publié le par Bernard Duyck
Publié dans : #volcanic activity

Sheveluch's intense explosive-effusive activity continues at high levels.

The thermal anomalies of August 22 are high, included this August 22 between VRP 156MW and 723 MW, according to the readings of Mirova.

During the high extrusive phase of the active lava dome over the past few weeks as it continues to grow, with magma rising in it, the lava dome frequently generates larger or smaller incandescent rockfall and more pyroclastic flows. small.

Sheveluch - The Glowing Dome on 08.22.2021 - photo @alexvush / Instagram via K. Bakhanov

Sheveluch - The Glowing Dome on 08.22.2021 - photo @alexvush / Instagram via K. Bakhanov

Sheveluch - thermal anomalies at 08/23/2021 / 3:05 am - Doc. Mirova_MODIS_Latest10NTI

Sheveluch - thermal anomalies at 08/23/2021 / 3:05 am - Doc. Mirova_MODIS_Latest10NTI

A stronger than usual explosion occurred on the volcano yesterday at around 6:20 p.m. local time, reported by local observers, and also confirmed by the Volcanic Ash Advisory Center (VAAC) in Tokyo.

An ash plume rose to an altitude of 3,700 m. and drifted southeast.
The explosion generated smaller streams of pumice and ash caused by the collapse of the eruption column.

 

Sources: Kiril Bakhanov / Alex Vush, KVERT & VAAC Tokyo

Sheveluch - explosive plume from 08.22.2021 - photo @alexvush / Instagram via K. Bakhanov

Sheveluch - explosive plume from 08.22.2021 - photo @alexvush / Instagram via K. Bakhanov

Sheveluch - Volcanic ash advisory of 22.08.2021 / 2310Z - Doc. VAAC Tokyo

Sheveluch - Volcanic ash advisory of 22.08.2021 / 2310Z - Doc. VAAC Tokyo

Moderate eruptive activity is underway at Chirinkotan in the Kuriles on August 22 and 23, 2021.

On August 22 at 22:35 UTC, an ash explosion was accompanied by a plume at 1,500-2,500 m. asl, drifting for 8 km. to OSO.

On August 23 at 05:20 UTC, the VAAC Tokyo reported an ash plume at an estimated height of 3,400 meters, moving 10 km to the SW.

The aviation code remains orange, with ash emissions continuing.

 

The 3 km-wide Chirinkotan volcano island is the emerging summit of a volcano that rises 3,000 meters from the bottom of the Kuril Basin. Its summit is 724 m high and is home to a one km caldera. wide, 300-400 m deep. open to the southwest. It sits at the end of an E-W-trending volcanic chain that stretches almost 50 km west of the central part of the main arc of the Kuril Islands. Historic eruptions have been recorded here since the 18th century, including one observed by Captain Snow.

 

Sources: KVERT, VAAC Tokyo & Global Volcanism Program

(a) Chirinkotan Island in July 2016 (Photo Y. Taran) and (b) its Google map image. View inside the Chirinkotan crater in August 2015. Photo O. Chaplygin. - via Reseach gate

(a) Chirinkotan Island in July 2016 (Photo Y. Taran) and (b) its Google map image. View inside the Chirinkotan crater in August 2015. Photo O. Chaplygin. - via Reseach gate

The Sernageomin reports a VT earthquake associated with the fracturing of rocks at Tupungatito / Chile , on August 22 at 11:47 a.m.

The volcanic alert remains at the verde level.

The Tupungatito volcano, the historically northernmost active volcano in the central Chilean Andes, is located along the Chile-Argentina border about 90 km east of Santiago and immediately southwest of the Pleistocene volcano Tupungato. Tupungatito consists of a cluster of 12 andesitic and basaltic Holocene andesite craters and a pyroclastic cone at the northwest end of the 4 km wide Pleistocene dacitic caldera Nevado Sin Nombre, which is filled of glaciers at its southern end and is pierced to the NW. Lava flows from the northernmost vent have passed through the breach on the northwest flank. The Tupungatito produced frequent light explosive eruptions during the 19th and 20th centuries. The last eruption was in November 1987

 

Sources: Sernageomin & Global Volcanism Program

Tupungatito - Photo by Sergio Kunstmann-Z, courtesy of Oscar González-Ferrán (University of Chile). / GVP-06918

Tupungatito - Photo by Sergio Kunstmann-Z, courtesy of Oscar González-Ferrán (University of Chile). / GVP-06918

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Publié le par Bernard Duyck
Publié dans : #volcanic activity

At Fagradalsfjall, around 6 p.m. on August 21, 2021, a breach opened in the southern lip of the active crater. Lava quickly rushed through this opening and began to flow to the south.

Lava is now starting to descend into Nátthaga from Meradalur. This is the first time that a visible flow has descended into the valley since the end of June.

Fagradalsfjall - event active at 08/21/2021 / 5:02 p.m. - RUV webcam

Fagradalsfjall - event active at 08/21/2021 / 5:02 p.m. - RUV webcam

Fagradalsfjall rash - activity changes - video Green Island Vid. - August 21, 2021 around 2:00 p.m.

Fagradalsfjall eruption - 08.21.2021 - lava as it enters Nátthaga; it will again be easier to observe - photos mbls
Fagradalsfjall eruption - 08.21.2021 - lava as it enters Nátthaga; it will again be easier to observe - photos mbls

Fagradalsfjall eruption - 08.21.2021 - lava as it enters Nátthaga; it will again be easier to observe - photos mbls

The eruption continues at a fluctuating rate, with a small increase during the day of August 21, as evidenced by the curve of the tremor.

Fagradalsfjall - tremor variations on 08/22/2021 - Doc. Hraun.vedur

Fagradalsfjall - tremor variations on 08/22/2021 - Doc. Hraun.vedur

Electricity company Landsnet announced that a ditch has been dug in the Nátthaga Valley near the Fagradalsfjall eruption site, where pipes and various insulation and filling materials were installed with the aim of assess the impact that the lava flow will have on such facilities.

After the ditch is closed and during the passage of the lava, the temperature in the ditch will be monitored by various agencies (Department of Civil Protection and Emergency Management, the University of Iceland Institute of Earth Sciences, the Icelandic Met Office, the National Power Company of Iceland, and others)

If this experience proves successful, the hope is to collect data, probably unique in the world and an essential contribution to understanding the effect of lava flows on cables and other infrastructure installed underground.

 

Sources: RUV, mbls, IMO, Hraun, Landsnet

Nátthaga valley - works carried out by Landsnet - photo Landsnet 20.08.2021 / via mbls

Nátthaga valley - works carried out by Landsnet - photo Landsnet 20.08.2021 / via mbls

Growth of the Sheveluch lava dome continues, strong fumarolic activity, and incandescence of the lava dome and hot avalanches accompany this process. Satellite data showed that a gas and vapor plume containing a certain amount of ash extended 307 km southeast of the volcano; thermal anomalies remain high on the volcano, with a VRP between 142 and 366 MW (last highest measured on 21.08 at 4:50 p.m. by Mirova.)

The aviation code remains Orange.

 

Source: KVERT, KSCNET & Mirova

Sheveluch, the eruptive plume seen from Klyuchi village 45 km SSO of the volcano on 08.22.2021 / 06:26 - IVS webcam, KVERT & Weathernews Inc. latest_Shv2

Sheveluch, the eruptive plume seen from Klyuchi village 45 km SSO of the volcano on 08.22.2021 / 06:26 - IVS webcam, KVERT & Weathernews Inc. latest_Shv2

The Tall volcano alert level of 2 shows increased activity.
Seismicity level: 142 volcanic earthquakes including 125 volcanic tremor episodes (duration 1 to 40 minutes) were recorded.
Sulfur dioxide flow: 5,973 tonnes / day (August 21, 2021); a rise of volcanic gas is observed in the lake, with generation of VOG.
pH: 1.59 (February 12, 2021)
Temperature: 71.8 (04 Mar 2021)
Plume of gas and steam at a height of 2,400 meters, and dispersal in a west, southwest and northwest sector.
Soil deformation: slow deflation of the TVI, slow expansion of the Taal mass.

 

Source: Phivolcs-DOST

Taal - activity summary dated 08/22/2021 - Doc. Phivolcs

Taal - activity summary dated 08/22/2021 - Doc. Phivolcs

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Fagradalsfjall - 08.19.2021 / 6:44 p.m. - RUV webcam

Fagradalsfjall - 08.19.2021 / 6:44 p.m. - RUV webcam

Fagradalsfjall - large crater overflow active on 08.19.2021 - via Ben Edwards

Fagradalsfjall - large crater overflow active on 08.19.2021 - via Ben Edwards

At Fagradalsjfall, the eruption continues with views of the active cone splashing with lava the NE rim of the crater on August 19, and showing flows entering Geldingadalur, Meradalur & SyðriMeradalur, in keeping with the style of building a lava shield

The lava flow on August 19 is shown schematically on the lava thickness map

 

Sources : Ben Edwards, volcanologist & Hraun.vedur.is

Fagradalsfjall - lava flows and main flow directions over the last 5 weeks, with change August 18-19, 2021 - map based on doc. Institute of Natural History & al

Fagradalsfjall - lava flows and main flow directions over the last 5 weeks, with change August 18-19, 2021 - map based on doc. Institute of Natural History & al

Fagradalsfjall - Trémor at 08.21.2021 - Doc. Hraun.vedur.is

Fagradalsfjall - Trémor at 08.21.2021 - Doc. Hraun.vedur.is

At Sheveluch, the growth of the lava dome continues: a strong fumarole activity, and an incandescence of the lava dome and hot avalanches accompany this process. Satellite data showed a plume of gas and steam containing a certain amount of ash reaching 4,000 m. asl., then extending 86 km east-southeast of the volcano. (data Himawari-8)

This extrusive eruption of the volcano continues, and ash explosions can occur at any time up to 10-15 km (32,800-49,200 feet) above sea level. Current activity could affect international and low-flying aircraft. The code aviatio is orange.

 

Sources : KVERT & Kamcharka-Inform

Sheveluch - photo Kamchatinfo 21.08.2021

Sheveluch - photo Kamchatinfo 21.08.2021

Sheveluch - Volcanic ash advisory of 21.08.2021 / 0000Z - Doc.VAAC Tokyo

Sheveluch - Volcanic ash advisory of 21.08.2021 / 0000Z - Doc.VAAC Tokyo

During the last 24 hours, the Taal volcano network has recorded one hundred and thirty-five volcanic earthquakes, including 112 volcanic tremor events with durations of 1 to 110 minutes, twenty-three low-frequency volcanic earthquakes and a bottom tremor of low level which 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 3000 meters high that drifted southwest and northeast. Sulfur dioxide emissions were on average 4,756 tonnes / day on August 20, 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) 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.

Source: Phivolcs

Taal - plume of gaz under the VOG this 08.21.2021 (contours of the lake of volcano island underlined) - photo Phivolcs

Taal - plume of gaz under the VOG this 08.21.2021 (contours of the lake of volcano island underlined) - photo Phivolcs

Taal - summary of the activity on 08/21/2021 - Doc. Phivolcs

Taal - summary of the activity on 08/21/2021 - Doc. Phivolcs

This week 13 to 19.08, 20 pyroclastic avalanche flows southwest of Merapi were observed, with a maximum slide distance of 3,500 m. Falls of incandescent boulders were observed 172 times towards the southwest with a maximum sliding distance of 2000 m.

Ash rains were reported in several areas on August 16, 2021, including Dukun, Sawangan, Tegalrejo, Secang, Gowok, Mertoyudan, Selo, Mojotengah, Temanggung, Kedu, Pringsurat, Bulu, Tlogomulyo, Kranggan and Parakan districts .

Morphological analysis of the Deles5, Tunggularum, Ngepos and Babadan2 camera stations showed that there were morphological changes in the southwest lava dome due to avalanches and hot clouds, while the central dome was relatively constant. The volume of the southwest lava dome is 1,350,000 m3.

The deformation of Mount Merapi, which was monitored using EDM this week, showed a distance shortening rate of 1.9 cm / day.

The state of the activity is defined in level 3 / Siaga

The current potential danger consists of lava avalanches and hot clouds in the southeast-southwest sector for a maximum of 3 km to the Woro River, and 5 km to the Gendol, Kuning, Boyong rivers. , Bedog, Krasak, Bebeng and Putih. Meanwhile, the ejection of volcanic material in the event of an explosive eruption can reach a radius of 3 km from the summit.

 

Source: BPPTKG

Merapi - morphological changes in the summit area between 13 and 19.08.2021 - Doc. BPPTKG

Merapi - morphological changes in the summit area between 13 and 19.08.2021 - Doc. BPPTKG

 Merapi - seismicity at 08.20.2021 - Doc. BPPTKG

Merapi - seismicity at 08.20.2021 - Doc. BPPTKG

Merapi - Pyroclastic flows of 08/17/2021 / 10:50 a.m. - Tunggularum webcam

Merapi - Pyroclastic flows of 08/17/2021 / 10:50 a.m. - Tunggularum webcam

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Taal - Vog on Lake Taal and the fisheries on 08.19.2021 / 1 p.m. drone images / video by Marlon Abuyo - one click to enlarge

Taal - Vog on Lake Taal and the fisheries on 08.19.2021 / 1 p.m. drone images / video by Marlon Abuyo - one click to enlarge

Opinion of the Phivolcs of August 19, 2021 / 4:30 p.m. concerning the high emissions of sulfur dioxide by the Taal volcano:

The first measurement of volcanic sulfur dioxide emitted from the main Taal crater this morning, August 19, 2021, reached 15,347 tonnes per day. This shows an increasing trend in SO2 emissions since August 13, 2021 with an average since then to this morning of 8,351 tonnes per day.

A steam-rich plume 1,000-3,000 meters high is generated by the main crater of Taal. Today there were temperatures of 32.2 ° C, relative humidity of 55.8% and slow wind gusts of only 0-2.3 m / s at speeds of up to 0-2.3 km / s.

High flux of SO2, water vapor emitted in the plume, weak wind movements and solar radiation can continue to create volcanic smog / VOG in the Taal area. DOST-PHIVOLCS has received reports of adverse effects on some residents of Talisay, Brgy, Barigon, and Agoncillo in Batangas province; foggy conditions are observed over Taal Lake and surrounding towns. {...}

Local governments are also encouraged to monitor the activities of aquaculture workers on Lake Taal, to ensure that no one approaches Taal Volcano Island at the risk of being exposed to lethal concentrations of sulfur dioxide.

Source: DOST-PHIVOLCS

Volcanic smog or vog seen over Taal Volcano caldera | 24 Oras GMA News

The Geospatial Information Authority of Japan analyzed satellite images observed by the NASA / US Geological Survey (USGS) Landsat-8 earth observation satellite at 10:00 a.m. (Japan time) on the 17th, and the shape of Niijima / Fukutoku Okanoba.

The West Island measures 2.5 km for an area of ​​0.3 km²; the eastern crescent measures 1.5 km for an area of ​​0.1 km².

We can see an erosion on the east side, with an advantage for the west side, compared to the first photos. .

 

Source: GSI

Fukutoku- Okanoba - seen by Landsat 8 L1 satellite on August 17, 2021 / Doc. GSI - one click to enlarge

Fukutoku- Okanoba - seen by Landsat 8 L1 satellite on August 17, 2021 / Doc. GSI - one click to enlarge

Fukutoku- Okanoba -measures of islets of Nijima - Doc. GSI 08/17/2021 - one click to enlarge

Fukutoku- Okanoba -measures of islets of Nijima - Doc. GSI 08/17/2021 - one click to enlarge

The extrusive eruption continues at Sheveluch.

The growth of the lava dome continues, a strong fumarole activity, and an incandescence of the lava dome and hot avalanches accompany this process. KVERT satellite data showed a thermal anomaly over the volcano all week; gas-steam plumes containing a certain amount of ash spread 370 km southwest, east and southeast of the volcano throughout the week.

The aviation color code is ORANGE. Ash explosions up to 10-15 km altitude. could arise at any time. Current activity could affect international and low-flying aircraft.

 

Source: KVERT

Sheveluch - thermal anomalies at 08/20/2021 / 02:35 - Doc. Mirova_MODIS_logVRP

Sheveluch - thermal anomalies at 08/20/2021 / 02:35 - Doc. Mirova_MODIS_logVRP

Sheveleuch thermal anomaly at the dome - image Sentinel-2 L1C bands 12,11,4 du 15.08.2021 / 00h-23h59 - - via Copernicus - one click to enlarge

Sheveleuch thermal anomaly at the dome - image Sentinel-2 L1C bands 12,11,4 du 15.08.2021 / 00h-23h59 - - via Copernicus - one click to enlarge

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
Nishinoshima, seen from the west on 08.16.2021 / 4:13 p.m. during the reconnaissance overflight by the JMA - Doc. 1.kaiho.mlit.go.jp

Nishinoshima, seen from the west on 08.16.2021 / 4:13 p.m. during the reconnaissance overflight by the JMA - Doc. 1.kaiho.mlit.go.jp

Nishinoshima, seen from the east on 08/16/2021 / 4:02 p.m. during the reconnaissance overflight by the JMA - Doc. 1.kaiho.mlit.go.jp

Nishinoshima, seen from the east on 08/16/2021 / 4:02 p.m. during the reconnaissance overflight by the JMA - Doc. 1.kaiho.mlit.go.jp

The Japan Meteo Agency / JMA reported that ash plumes from Nishinoshima in the Ogasawara Islands were visible on satellite images on August 14, rising about 1,900 meters and drifting north. The Japanese Coast Guard carried out an overflight the next day and did not observe any eruptive activity or new deposits the day before.

The central crater is well open and occupies a large part of the island.

The Tokyo VAAC noted that a period of continuous ash emissions was visible in satellite data on August 15.

 

Sources: JMA & VAAC Tokyo

Nishinoshima, the crater on 08.16.2021 / 4:15 p.m. during the reconnaissance overflight by the JMA - Doc. 1.kaiho.mlit.go.jp

Nishinoshima, the crater on 08.16.2021 / 4:15 p.m. during the reconnaissance overflight by the JMA - Doc. 1.kaiho.mlit.go.jp

A strong eruptive episode occurred at Suwanosejima (Mitake crater), in the Ryukyu arc, at 1:37 a.m. on August 19, and the plume of the eruption rose 3,000 m above the edge of the crater, crossed by lightning.
Volcanic ash was observed northeast of the crater and at 8 a.m. on the 19th there was a fairly large amount of ash in the village of Toshima.
They should reach the city of Nishinoomote, Kojima prefecture.
Slightly large quantity Kagoshima Prefecture: Toshima Village
Small quantity Kagoshima Prefecture: Yakushima Town, Nishinoomote Town, Nakatane Town

 

Source: JMA

Suwanosejima - eruptive episode of 08.19.2021 / 01.40 a.m. - JMA webcams

Suwanosejima - eruptive episode of 08.19.2021 / 01.40 a.m. - JMA webcams

A new vent, which opened in Geldingadalur on August 9, was not confirmed to be separated from the neighboring main vent until about a week later. The new cone grew rapidly due to the intense spattering , and by August 17 it was at about the same height as the main crater. Spattering from the new vent was at times ejected higher than spatter from the main vent.

The aviation color code remained at Orange for Fagradalsfjall due to the lack of ash and tephra emissions, although IMO warned of the potential for lapilli and slag fallout within a radius of 650 m from the active vent. Authorities have also warned of the dangers of gas emissions.

 

Sources : mbls, Iceland Review, Almannavarnir, IMO, Global Volcanism Program weekly report

Fagradalsfjall eruption - image Sentinel-2 bands 12,11,8A from 17.08.2021

Fagradalsfjall eruption - image Sentinel-2 bands 12,11,8A from 17.08.2021

Fagradalsfjall - active zone on 08/18/2021 / 11:10 a.m. - webcam Almananavarnir

Fagradalsfjall - active zone on 08/18/2021 / 11:10 a.m. - webcam Almananavarnir

Fagradalsfjall - tremor at 19.08.2021 - Doc. Hraun.vedur

Fagradalsfjall - tremor at 19.08.2021 - Doc. Hraun.vedur

Opinion of the Police du Suðurnes:

We need your help to protect Geldingardalir's unique lava

Please do not:
- walk on lava
- throw stones or garbage on the lava
- make inscriptions on it
Even when no activity is visible in the crater, the eruption is still active. Under the hardened top layer of lava, hot lava can flow. The top layer can easily break when walked on, causing hazards to people and damage to geological monuments.


Geldingadalir lava is a unique geological monument that we must respect and protect. It is important that visitors do not leave any traces such as throwing stones on the lava or making inscriptions on it. The lavas are under special protection according to art. 61 of the Nature Protection Act.

(Lögreglan to Suðurnesjum)

Reminder of the rules to be observed on lava in Iceland - Doc. Lögreglan in Suðurnesjum - one click to enlarge
Reminder of the rules to be observed on lava in Iceland - Doc. Lögreglan in Suðurnesjum - one click to enlargeReminder of the rules to be observed on lava in Iceland - Doc. Lögreglan in Suðurnesjum - one click to enlargeReminder of the rules to be observed on lava in Iceland - Doc. Lögreglan in Suðurnesjum - one click to enlarge

Reminder of the rules to be observed on lava in Iceland - Doc. Lögreglan in Suðurnesjum - one click to enlarge

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Publié le par Bernard Duyck
Publié dans : #volcanic activity

The moderate eruptive activity of the Chirinkotan volcano, in the Kuriles, continues. The explosive event of the volcano began at 12:10 UTC on August 18, accompanied by a plume of 3,000 m. asl ..

A 20x27 km ash cloud continues to drift 101 km south-southeast of the volcano, according to data from the Himawari-8 satellite

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. The current activity could affect international and low-flying aircraft, which justifies that the aviation code remains at Orange.

 

Source: KVERT, VAAC Tokyo & Sentinel-2

Chirinkotan - activity of 18.08.2021 largely masked by cloud cover - image Sentinel-2 bands 12,11,4 / Copernicus

Chirinkotan - activity of 18.08.2021 largely masked by cloud cover - image Sentinel-2 bands 12,11,4 / Copernicus

The Fukutoku-Okanoba volcano belongs to a partially submerged chain of volcanoes known as the Izu-Bonin-Mariana Arc, where the Pacific oceanic plate sinks below the oceanic plate of the Philippine Sea. This subduction is responsible for the volcanic activity.

Following the phreatomagmatic eruption of August 13, 2021 (see the articles of the previous days), an island was formed; it is crescent-shaped with a bay pierced above the underwater vent, and is composed of unstable materials, ashes and blocks.

The sustainability of this new island will depend on future activity: if lava flows are produced which will seal the first materials, its probable survival is likely to increase.

The Niijima, formed with a diameter of about 1 km, is already changing due to marine erosion.

The danger in the immediate vicinity is linked to the production of volcanic bombs, or even to a possible base surge. The ash emitted at the start of the eruption disrupted aviation, but this activity has stopped for the moment.

 

Sources: Japan Météo Agency and Japan Coast Guards.

Fukutoku-Okanoba - the ephemeral island formed by the recent eruption - photo Japan Coast Guards 08/16/2021 / 1:50 p.m. - one click to enlarge

Fukutoku-Okanoba - the ephemeral island formed by the recent eruption - photo Japan Coast Guards 08/16/2021 / 1:50 p.m. - one click to enlarge

Fukutoku-Okanoba - pumice rafts around the eruption site - photo Japan Coast Guards 08/16/2021 / 3:08 p.m. - one click to enlarge

Fukutoku-Okanoba - pumice rafts around the eruption site - photo Japan Coast Guards 08/16/2021 / 3:08 p.m. - one click to enlarge

The week of August 9 to 15 was characterized at Etna by Strombolian activity and an episode of lava fountain from the Southeast Crater (SEC), occasional ash emissions at the Northeast Crater (NEC), degassing ordinary at the crater of Bocca Nuova (BN) and a fumarolic degassing at the crater of Voragine (VOR). Over the past week, there has been no significant change after the previously reported August 9 lava fountain event, and the lava flows in the Valle del Bove.

Seismic fracturing activity remained low.

The amplitude of the volcanic tremor stagnates on the medium-low level. Large and sudden fluctuations up to high values ​​can be correlated with
explosive activity at the Southeast Crater.
The infrasound activity is moderate.

 

Source: INGV OE - weekly bulletin

Map of the summit craters of Etna on a shaded model of the terrain. The lava flows of August 9, 2021 that flowed into the Valle del Bove are mapped. BN: Bocca Nuova, VOR: Voragine; NEC: northeast crater; SEC: south-eastern crater. The topographic reference frame on which the morphological updates are superimposed is the DEM 2014 developed by the Aerogeophysical Laboratory - Section Rome 2.

Map of the summit craters of Etna on a shaded model of the terrain. The lava flows of August 9, 2021 that flowed into the Valle del Bove are mapped. BN: Bocca Nuova, VOR: Voragine; NEC: northeast crater; SEC: south-eastern crater. The topographic reference frame on which the morphological updates are superimposed is the DEM 2014 developed by the Aerogeophysical Laboratory - Section Rome 2.

Etna summit craters - image Sentinel-2 L1C bands 12,11,8A from 08.10.2021 - one click to enlarge

Etna summit craters - image Sentinel-2 L1C bands 12,11,8A from 08.10.2021 - one click to enlarge

Etna - SEC activity on 08.09.2021 / photo Gio Giusa - & explosion at the NE crater on 08.10.2021. / Etna News - one click to enlargeEtna - SEC activity on 08.09.2021 / photo Gio Giusa - & explosion at the NE crater on 08.10.2021. / Etna News - one click to enlarge

Etna - SEC activity on 08.09.2021 / photo Gio Giusa - & explosion at the NE crater on 08.10.2021. / Etna News - one click to enlarge

Þorvaldur Þórðarson, professor of volcanology, announces in an interview with RUV, that the new crater appears to be independent of the old crater ... It is interesting to note that all types of basalt lava, the temperature of which has been measured up to at 1,240 ° C, which can form above sea level, formed at Fagradalsfjall : pahoehoe lava, smooth or corded, 'a'a lava, "toothpaste" lava (unspecified) .

The factors influencing the type of formation depend on how the lava cools, its viscosity and the terrain over which it flows.

 

As for fluctuations in activity, one hypothesis involves the formation of giant gas bubbles. The magma which rises releases the gases in bubbles which spread in series, in flow, which produces an emission of lava in cycles.

 

Sources: RUV, Iceland Review

Fagradalsfjall - interesting variations in lava textures: 'a'a, smooth and corded pahoehoe - photo Ben Edwards 07.08.2021 / Twitter

Fagradalsfjall - interesting variations in lava textures: 'a'a, smooth and corded pahoehoe - photo Ben Edwards 07.08.2021 / Twitter

Fagradalsfjall - variations of the tremor on 08/18.32021 - Doc. Hraun.vedur

Fagradalsfjall - variations of the tremor on 08/18.32021 - Doc. Hraun.vedur

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
 Sheveluch - thermal anomaly at the dome on 08.15.2021 - image Sentinel-2 L1C bands 12.11.4 / via Copernicus - one click on the photo to enlarge

 Sheveluch - thermal anomaly at the dome on 08.15.2021 - image Sentinel-2 L1C bands 12.11.4 / via Copernicus - one click on the photo to enlarge

At Sheveluch, the growth of the lava dome continues: a strong fumarole activity, and an incandescence of the lava dome and hot avalanches accompany this process.

Satellite / Suomi NPP data showed a gas and vapor plume at 3,000-3,500 m. asl, containing a certain amount of ash, and extending about 100 km east-southeast of the volcano.

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

 

In the KVERT control zone, four volcanoes are today in aviation code orange: Sheveluch, Karymsky, Ebeko and Chirinkotan; the Bezimianny is in yellow aviation code.

 

Source: KVERT

Sheveluch - thermal anomals at 05.16.2021 / 03.00 a.m.- Doc. Mirova_MODIS_Latest10NTI

Sheveluch - thermal anomals at 05.16.2021 / 03.00 a.m.- Doc. Mirova_MODIS_Latest10NTI

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.

Satellite imagery d16.08 at noon showed that the lava dome is now greater than 700 m in diameter. (against 380 m. on 08/09). A plume of steam and gas could be seen above the summit on satellite images and by ground observers. No explosion or ash emission was detected.

The current volcanic alert level remains at Watch and the aviation code at Orange.

 

Source: AVO

Great Sitkin - the growing dome - photo Peggy Kruse 10.08.2021 / AVO - one click to enlarge

Great Sitkin - the growing dome - photo Peggy Kruse 10.08.2021 / AVO - one click to enlarge

At Merapi, a moderate to thick white plume was observed at the main crater about 200 meters from the summit. The weather is sunny to cloudy, the wind is weak to moderate in the west.

The seismicity of August 17, 2021 is characterized by
- 4 earthquakes linked to the pyroclastic flows of collapse, with an amplitude of 15-52 mm and an earthquake duration of 62-128 seconds.
They occurred at 5:18 am WIB, 7:01 am WIB, 9:39 am WIB and 10:49 am WIB respectively.
- 73 collapse avalanche earthquakes, with an amplitude of 3 to 40 mm and a duration of 17 to 136 seconds.
- 3 blast / emission earthquakes, with an amplitude of 3 to 8 mm and an earthquake duration of 17 to 21 seconds.
- 6 hybrid / multiphase earthquakes
- 1 shallow volcanic earthquake
- 1 distant tectonic earthquake.

 

Sources: Magma Indonesia, BPPTKG

Merapi - Pyroclastic flow of collapse on 08/17/2021 / 07:46 a.m. - webcam Panguk / Badan Geologi

Merapi - Pyroclastic flow of collapse on 08/17/2021 / 07:46 a.m. - webcam Panguk / Badan Geologi

Merapi - Collapse pyroclastic flow of collapse on 08/17/2021 / 10:50 a.m. - Tunggularum / Badan Geologi webcam

Merapi - Collapse pyroclastic flow of collapse on 08/17/2021 / 10:50 a.m. - Tunggularum / Badan Geologi webcam

At Fagradalsfjall, it seems that a new small spatter cone has started to develop at the edge of the eruptive center, with an independent and powerful crater.

Observers dated its opening the same day the Gónhóll fissures were discovered and may have appeared.

The thermal anomalies noted by Mirova were very high on August 16, with a maximum at VRP 5262 MW at 2:35 p.m.

 

Sources: mbls, RUV, Mirova

Fagradalsfjall - new spatter cone on the side of the eruptive cone on 08.16.2021 / 6:06 p.m. - mbls webcam

Fagradalsfjall - new spatter cone on the side of the eruptive cone on 08.16.2021 / 6:06 p.m. - mbls webcam

Fagradalsfjall - the night was hot - Visir webcam 08/17/2021 / 12:05 am

Fagradalsfjall - the night was hot - Visir webcam 08/17/2021 / 12:05 am

Krisuvik - thermal anomalies at 08/17/2021 / 04h00 - Doc. Mirova_MODIS_Latest10NTI

Krisuvik - thermal anomalies at 08/17/2021 / 04h00 - Doc. Mirova_MODIS_Latest10NTI

Sabancaya's activity remained moderate between August 9 and 15, 2021, with an average of 29 explosions per day, accompanied by plumes of gas and ash up to 3,000 meters above the summit.

During this week, I.G. Peru detected and analyzed 826 earthquakes of volcanic origin linked to the circulation of internal magmatic fluids. The VT earthquakes remain localized to the north and northwest of the volcano.

The deformation does not present any significant anomalies.

Four thermal anomalies, with a max. de11 MW were identified by Mirova, associated with the presence of a surface lava body in the crater.

 

Sourec: I.G. Peru

Activity of Sheveluch, Great Sitkin, Merapi, Fagradalsfjall and Sabancaya.

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