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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

Deferred by the news of Krakatau and Etna, return to the balance sheets of the year by the observatories:

 

In 2018, the Volcanic Monitoring Program developed several tools to improve the communication of the results of the continuous monitoring of volcanoes, including a scale of activity level, weekly and daily bulletins, and webcam views. seismic activity and gas geochemistry on the OVSICORI-UNA website: http://www.ovsicori.una.ac.cr/.

Volcanic monitoring is done from a network of different devices.

 

Costa Rica - scale of activity of volcanoes in 2018 - Doc.Ovsicori

Costa Rica - scale of activity of volcanoes in 2018 - Doc.Ovsicori

More specifically for active volcanoes in 2018:

The Turrialba is in activity level in 2018: 3 (erupting volcano) with an open system activity, generating frequent passive emissions of ash due to the slow but almost constant increase of a small magmatic volume.

On the 336 days of the year until December 20, the volcano emitted ashes for 194 days, more than 58% of the days of this year. At the beginning of the year and in August-September 2018, 2 inflation periods were detected that could be associated with a magmatic intrusion of 15 to 20 million cubic meters, at a depth of 10 to 15 km below the sealevel, located 3 km southeast of Irazú crater. These intrusions could be at the origin of the increase of eruptive activity on the volcano between February and March, as well as from May to October 2018.

Some explosions generated by these impulses were large enough to trigger a ballistic activity greater than 400 m around the crater.

Since the end of October, the magmatic activity has decreased but not the ash emissions. The hydrothermal system is considered to be formed again by generating explosive magma-water interactions and fragmentation of the magma in the column as the origin of ash emissions.

 Turrialba - summit on 30.11.2018 - photo jcarvaja17 / via Exploring Costa Rica

 Turrialba - summit on 30.11.2018 - photo jcarvaja17 / via Exploring Costa Rica

 Turrialba - 09.12.2018 - RSN webcam

 Turrialba - 09.12.2018 - RSN webcam

The Poas volcano is in activity level in 2018: 2 - 3 (active volcano - erupting)

It showed low activity, dominated by hydrothermal processes and degassing. Several periods of sustained activity have been recorded in the form of "borbollones".

In general, the flow of gas has significantly decreased compared to 2017 and the hydrothermal system has begun to reform, as evidenced by the recovery of the lake since January. This lake disappeared during the dry season (March-May) and reappeared later, generating variability in the monitored signals (seismicity, flow and gas ratios). The deformation recorded a slight deflation from June. No magmatic intrusion was detected.

The color of the lake changed from gray to green at the end of the year, which is generally associated with less intense convection activity in the lake despite the active maintenance of underwater fumaroles. And in mid-December 2018, eruptive activity increased, with hydrothermal eruptions with steam columns on December 19 and 20, and the near-disappearance of crater lake.

A change in the seismic model appeared on October 8 with many high amplitude LPs and short duration tremors, with no superficial manifestations.

Poas - modification of acid lake coloration 08.12.2018 - photo RSN

Poas - modification of acid lake coloration 08.12.2018 - photo RSN

Poas - plume of the phreatic eruption of 20.12.2018 / 8h19 - photo RSN

Poas - plume of the phreatic eruption of 20.12.2018 / 8h19 - photo RSN

The Rincon de la Vieja volcano has maintained an intense activity with frequent phreatic eruptions, but of a smaller amplitude than in 2017. A modification of the deformation model towards the extension was observed in October.

Rincon de la Vieja - phreatic eruption from 03.03.2018 / 16h12 - photo Ovsicori

Rincon de la Vieja - phreatic eruption from 03.03.2018 / 16h12 - photo Ovsicori

In 2018, volcanic activity associated with Irazú volcano remained very low. Some seismic swarms were recorded around May 20th. A permanent multi-gas station has been installed to detect the first signs of a possible magma intrusion. At present, no magmatic activity related to the Irazú volcano is detected.

 Irazu - photo 12.12.2018 / MSc. Elena Badilla Coto, profesor of Escuela Centroamericana de Geología UCR.

 Irazu - photo 12.12.2018 / MSc. Elena Badilla Coto, profesor of Escuela Centroamericana de Geología UCR.

The activity level of the Arenal in 2018: 0 (asleep) with potentially associated risks of earthquakes and landslides.

The deformation associated with the stabilization of the flanks of the volcanic building has decreased this year 2018. Some isolated LP earthquakes have been recorded that do not represent a new activity in the volcano. DOAS transects indicate that there is no SO2 emission. No magmatic activity was detected.

Source: Ovsicori - UNA & Red Sismologica Nacional

Arenal - photo tiempo CR 2018

Arenal - photo tiempo CR 2018

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
Anak Krakatau - plume of 26.12.2018 - Photo by sukamdani_gunners543 Indonesian navy warship

Anak Krakatau - plume of 26.12.2018 - Photo by sukamdani_gunners543 Indonesian navy warship

Anak Krakatau - 26.12.2018 - we can see "the remains of the cone" between the islands - photo Du2nZizouEffenberg / Twitter

Anak Krakatau - 26.12.2018 - we can see "the remains of the cone" between the islands - photo Du2nZizouEffenberg / Twitter

After the eruptive sequence of December 22, with a continuous tremor with an excessive amplitude of 58 mm, the Anak Krakatau was marked at 21:03 WIB by a strong eruption.

Based on the satellite images, the PVMBG concludes that most of the Anak Krakatau has disappeared, causing a tsunami with deadly repercussions.

 

Since December 22, a sustained plume is emitted, and the seismicity is dominated by a continuous tremor, with a dominant at 25 mm (max 32 mm).

The volcanic ash is mostly distributed to the southwest, according to satellite radar images, this December 26th.

The satellites indicate heights between 15 and 18 km AGL at the point of emission (NOAA HYSPLIT model) and a displacement at more than 10 km altitude over a maximum of 130 km.

Ash falls are reported on Cilegon city and Serang this 26.12 to 17h WIB. (Liputan6)

Sulfur dioxide readings indicate a total mass of 0.022 Tg on December 26 at 19h UTC / 27.12 at 6hlocale (AIRS SO2)

Anak Krakatau - images of the plume on 26.12.2018, at 21.30 WIB and 27.12.2018 at 0:00 WIB - images Himawari RGB Citra - one click to enlargeAnak Krakatau - images of the plume on 26.12.2018, at 21.30 WIB and 27.12.2018 at 0:00 WIB - images Himawari RGB Citra - one click to enlarge

Anak Krakatau - images of the plume on 26.12.2018, at 21.30 WIB and 27.12.2018 at 0:00 WIB - images Himawari RGB Citra - one click to enlarge

Anak Krakatau - Analysis of radar images and ash trajectories on 24.12.2018 - sources: BPPT and NOAA HYSPLIT model
Anak Krakatau - Analysis of radar images and ash trajectories on 24.12.2018 - sources: BPPT and NOAA HYSPLIT model

Anak Krakatau - Analysis of radar images and ash trajectories on 24.12.2018 - sources: BPPT and NOAA HYSPLIT model

Anak Krakatau - Sulfur dioxide flow 27.12.2018 at 6am local (26.12 / 19h UT) - Doc AIRES - Total SO2 mass estimated at 0.022 Tg by S.Carn

Anak Krakatau - Sulfur dioxide flow 27.12.2018 at 6am local (26.12 / 19h UT) - Doc AIRES - Total SO2 mass estimated at 0.022 Tg by S.Carn

Given the parameters and terrible weather, the PVMBG decided to raise the Krakatau alert level to 3 / siaga, with a prohibited area of ​​5 km radius, December 27 at 6:00 WIB. A Volcano Observatory Notice for Aviation / VONA Red is issued from 27 December.
From yesterday to this morning, a visual contact makes it possible to observe a black and thick plume rising about 700 meters, with a wind blowing to the north and the east.

Status Gunungapi Diatas Normal

G. Sinabung

AWAS

02-06-2015

G. Anak Krakatau

Siaga

27-12-2018

G. Karangetang

Siaga

20-12-2018

G. Soputan

Siaga

03-10-2018

G. Agung

Siaga

10-02-2018

G. Merapi

Waspada

21-05-2018

Sources: PVMBG, Magma Indonesia, BNPB, and local press.
 

A link to the site and images of Øystein Lund Andersen, with his version of events on December 22 - link 

Etna - top degassing - photo J.Nasi / Butterfly Helicopters 26.12.2018 / 15h46 GMT

Etna - top degassing - photo J.Nasi / Butterfly Helicopters 26.12.2018 / 15h46 GMT

At Etna, the INGV specifies that the M4.8 earthquake of December 26 at 3:19 am is probably related to the activation of Fiandaca and Pennisi faults, and associated surface faults.

The earthquake would not be generated by magmatic movements, but constitutes a response of the volcano to a stress resulting from the intrusion and its transfer to the surrounding tectonic structures.

The seismic swarm has temporarily reached the number of 1,100 episodes, of which 60 exceed a magnitude of M2.5; the tremor after on increasing on 24,12, decreases slightly, still above the norm.

The general eruptive activity indicates a decrease, but one can not exclude a possible refeeding, on the basis of the geophysical signals, and an opening of new fractures to alitudes lower than 2,400 meters.

 

Source: INGV Catania

Etna - hot points and lava flows -  Sentinel 2 images 26.12.2018, respectively SWIR & Bands 12,11,4
Etna - hot points and lava flows -  Sentinel 2 images 26.12.2018, respectively SWIR & Bands 12,11,4

Etna - hot points and lava flows - Sentinel 2 images 26.12.2018, respectively SWIR & Bands 12,11,4

Etna tremor - diagram at 27.12.2018 / 0h40 - Doc. INGV Catania

Etna tremor - diagram at 27.12.2018 / 0h40 - Doc. INGV Catania

Etna - the NSEC - photo Gianni Pennisi 26.12.2018

Etna - the NSEC - photo Gianni Pennisi 26.12.2018

Note that the seismic activity of Stromboli was marked on December 24, between 8:00 and 8:20 local, by a series of signals repeating at regular intervals of 30 seconds for fifteen minutes.The frequency and shape of the wave are compatible with a fracking phenomenon likely to be located in the summit zone. (LGS / Laboratorio Geofisica sperimentale).

The alert level has therefore been raised from green to yellow, / unstable situation, and this although local observers do not notice more significantly larger explosions than usual.

 

Sources: LGS & INGV

Stromboli - seismogram of 24.12.2018 - see box in pink / 8h - 8h20 - Doc. LGS

Stromboli - seismogram of 24.12.2018 - see box in pink / 8h - 8h20 - Doc. LGS

In the Philippines, two phreatic eruptions are reported at Mayon this 27th of December at 8:17 and 8:28; they were accompanied by gray to greyish plumes rising respectively 600 and 200 meters above the summit, before drifting to the southwest.

During the previous 24 hours, a volcanic earthquake was recorded, as well as nighttime glow.

Inflation in the southeastern sector is still noticeable, and sulfur dioxide flux is measured at 1,943 tonnes / day on 25 November.

The alert level remains at 2.

Source: PHIVOLCS

Mayon - plume of the phreatic eruption this 27.12.2018 / at 8:19 - photo Kit / Twitter

Mayon - plume of the phreatic eruption this 27.12.2018 / at 8:19 - photo Kit / Twitter

A new lava flow / incandescent debris was observed at Merapi / Java on December 27 at 2:50 am HNE, about 300 meters long. The alert level remains unchanged.

Source: Merapi Observatory

Merapi - flow at 2:50 am on 27.12.2018 - Observatory Doc Merapi

Merapi - flow at 2:50 am on 27.12.2018 - Observatory Doc Merapi

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Publié le par Bernard Duyck
Publié dans : #volcanic activity

Sentinel 2 satellite images show that the activity of Karangetang / Api Siau , effusive since the end of November, continues on December 25 in the direction of the gorges located in the west-west.

The seismicity is directed since December 5-6 to avalanches of erosion of the lava  (guguran) until about December 22, before taking on a new aspect.

The Karangetang is in activity level 3 / Siaga, with a forbidden zone of 2.5 km to the northeast and southwest, increased to 3 km to the northwest. A Vona is orange, issued on 25.11.2018.

Sources: Magma Indonesia & Sentinel 2

Karangetang - 25.12.2018 - images Sentinel2 SWIR (above) and bands 12,11,8A (underneath) - one click to enlarge
Karangetang - 25.12.2018 - images Sentinel2 SWIR (above) and bands 12,11,8A (underneath) - one click to enlarge

Karangetang - 25.12.2018 - images Sentinel2 SWIR (above) and bands 12,11,8A (underneath) - one click to enlarge

Karangetang - table of seismicity at 25.12.2018 - Doc. Magma Indonesia

Karangetang - table of seismicity at 25.12.2018 - Doc. Magma Indonesia

At Anak Krakatau, still no new topographic data after the collapse that seems to be confirmed, due to significant cloud cover.

The lightning detection system provides information on a significant number of lightning flashes produced in the area over the last three days, the only sign of significant activity due to the interaction of magma with seawater.

Anak Krakatau - Tsunami trigger mechanism - 25.12.2018 - UNFPA Asia & Pacific

Anak Krakatau - Tsunami trigger mechanism - 25.12.2018 - UNFPA Asia & Pacific

Anak Krakatau -  analysis of image Sentinel-1 Citra radar at 23.12.2018

Anak Krakatau - analysis of image Sentinel-1 Citra radar at 23.12.2018

Anak Krakatau - synoptic table summarizing the mechanisms lead to the disaster, and counting the number of victims of the tsunami - via Antara

Anak Krakatau - synoptic table summarizing the mechanisms lead to the disaster, and counting the number of victims of the tsunami - via Antara

The seismicity table reveals only continuous tremor of amplitude 8-40mm, with a dominant at 20 mm.

The level of activity remains fixed at 2 / waspada, with a prohibited area of ​​2 km radius.

Sources: PVMBG, BNPB, Magma Indonesia

Probably one of the last photos of Anak Krakatau before its partial collapse in the ocean, and its change of appearance. - a collector by photo Øystein Lund Andersen 22.12.2018 / 18:59 local time

Probably one of the last photos of Anak Krakatau before its partial collapse in the ocean, and its change of appearance. - a collector by photo Øystein Lund Andersen 22.12.2018 / 18:59 local time

At Etna, details are provided by the INGV on the site of the last lava flows:

The eruptive fissure extended from the southeastern base of the new southeast crater to the west wall of the Valle del Bove, reaching a minimum altitude of about 2,400 meters above sea level. A second small eruptive fissure opened a little further north, at about 3,000 meters above sea level, between the new southeastern crater and the northeastern crater, and produced almost exclusively low Strombolian activity. for a few tens of minutes.

During its propagation, the open eruption fissure in the Valle del Bove fed lava flows that completely crossed the west wall of the valley, reaching its bottom and settling at 17:00 UTC on December 24, at varying altitudes of 1650 and 1800 meters.

In the early hours of December 25, the eruption is still in progress. A lava flow continues to flow into the Valle del Bove, fed by the eruptive fracture whose lower mouth is located at about 2400 m altitude, along the western wall of the valley.

Summit craters, particularly New Bocca craters and Northeast craters, produce continuous Strombolian activity that feeds a gaseous plume rich in volcanic ash.

The seismic swarm that accompanies the eruption continues; since yesterday morning, in about twenty-four hours, more than 900 seismic shocks have been recorded by the seismic network of the INGV Osservatorio Etneo.

During the night, from midnight, seven earthquakes were recorded, including one of M 3.3 at 01:09, with its epicenter 4 km north of Aci Sant'Antonio; an earthquake of M 4.8 at 3:18, with its epicenter 2 km north of Viagrande, was felt by the population and caused damage to Santa Venerina, Fleri and Lavinaio.

A section of the A18 Catania-Messina has been closed, where it appears that there has been a lowering of the road surface near Acireale.
At present, there are no casualties or serious injuries, only damage.

Sources: INGV Catania & local press

Etna - eruptive fissure at the base of the NSEC and flows towards the Valle del Bove - photo 24.12.2018 Emilio Messina

Etna - eruptive fissure at the base of the NSEC and flows towards the Valle del Bove - photo 24.12.2018 Emilio Messina

Etna - tremor at 26.12.2018 / 3:10 - Doc. INGV Catania

Etna - tremor at 26.12.2018 / 3:10 - Doc. INGV Catania

Etna - seismogram of the M4.8 earthquake of 26.12.2018 / 02:18 UTC - Doc. INGV

Etna - seismogram of the M4.8 earthquake of 26.12.2018 / 02:18 UTC - Doc. INGV

Etna - night earthquake damage in Fleri, Santa Venerina - photo Sabian Quattrocchi - one click to enlarge
Etna - night earthquake damage in Fleri, Santa Venerina - photo Sabian Quattrocchi - one click to enlarge

Etna - night earthquake damage in Fleri, Santa Venerina - photo Sabian Quattrocchi - one click to enlarge

In Ambrym / Vanuatu, the volcano is in minor eruption, level 3 with zones of danger unchanged.

This eruption is linked to a strong seismicity that could continue to affect existing fissures, especially in the southeastern part of the island.

As the analysis of the satellite data confirms a deformation of ground, other earthquakes are expected, perceptible or not by the population according to their magnitude.

Source: VMGD

Ambrym - earthquakes between 14 and 26 December 2018 serialized by dates / colors - Doc. GMVD

Ambrym - earthquakes between 14 and 26 December 2018 serialized by dates / colors - Doc. GMVD

Ambrym - 23.12.2018 deformation - deep source deflation and ERZ intrusion - Doc. VMGD GNS - JAXA

Ambrym - 23.12.2018 deformation - deep source deflation and ERZ intrusion - Doc. VMGD GNS - JAXA

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Publié le par Bernard Duyck
Publié dans : #volcanic activity

Short news on this Christmas day ...

 

The new eruptive phase, started yesterday December 24 (see article), is after Boris Behncke the first flank eruption of Mount Etna for more than ten years on this site.

 Etna - 24.12.2018 - photo Guido La Rosa via Etna web

 Etna - 24.12.2018 - photo Guido La Rosa via Etna web

A new crack opened in the morning at about 3,000 meters above sea level at the base of the new south-east crater on the western flank of Valle del Bove, feeding a lava flow.

The entire summit area is deformed, and strombolian activity also concerns the northeast crater and the Bocca Nuova.



 

Etna - flank eruption started on 24.12.2018 - Lava flow in the Valle del Bove / Volcanodiscovery

The situation poses no danger for the inhabitants; only ashes and lapilli issued to a southeastern sector forced the partial closure of the Catania airport at 13:00 UTC, diverting incoming flights to other locations.

Falls of ashes and lapilli are reported on Zafferana, Santa Venerina and the south-east sector.

Etna - ash emissions cause diversion of flights to Catania - ash forecast for this 25.12.2018 / 00 to 18h by AshMALTA - one click to enlargeEtna - ash emissions cause diversion of flights to Catania - ash forecast for this 25.12.2018 / 00 to 18h by AshMALTA - one click to enlarge

Etna - ash emissions cause diversion of flights to Catania - ash forecast for this 25.12.2018 / 00 to 18h by AshMALTA - one click to enlarge

Etna - the fissural eruption this 24.12.2018 / 11:33 GMT - photo J.Nasi / Butterfly Helicopters

Etna - the fissural eruption this 24.12.2018 / 11:33 GMT - photo J.Nasi / Butterfly Helicopters

Etna - the lava flow in the Valle del Bove on 24.12.2018 / 17h50 - photo Basalto Caruso / Facebook

Etna - the lava flow in the Valle del Bove on 24.12.2018 / 17h50 - photo Basalto Caruso / Facebook

At the seismicity level, it is necessary to point a quake of magnitude 4.3 at 17:50, at a depth of 2 km. with its epicenter west of Zafferana Etna, marked by some damage. It was felt until Catania (INGV Terremoti).

Etna - earthquake of 24.12.2018 / 17:50 on the seismogram INGV ESVO_HHZ_IT.0004

Etna - earthquake of 24.12.2018 / 17:50 on the seismogram INGV ESVO_HHZ_IT.0004

Earthquake M4,3 recorded while recording this video on Mount Etna ! New eruption with lava flow - by Turi Caggegi

Thermal anomalies are high with a maximum of 2.294 MW on 24.12 / 21.15 (Mirova)

Incandescent mark three craters and the flank of Etna on a Sentinel 2 image of 24,12,2018 bands 12,11,8A.

 

Sources : INGV Catania and the different webcams and photographers mentioned, Sentinel 2

Etna - thermal anomalies at 25.12.2018 / 01h25 - Doc. Mirova_MODIS_Latest10NTI

Etna - thermal anomalies at 25.12.2018 / 01h25 - Doc. Mirova_MODIS_Latest10NTI

Etna - image Sentinel 2 bands 12,11,8A from 24.12.2018 - one click to enlarge; in this configuration, the snowy areas are in blue.

Etna - image Sentinel 2 bands 12,11,8A from 24.12.2018 - one click to enlarge; in this configuration, the snowy areas are in blue.

In Indonesia, after the tsunami, joint teams of the armed forces, the BPBD, the police, and many volunteers continue the search for survivors. The small islands between Krakatau and the coast of Sumatra are visited by boat.

The balance sheet is unfortunately heavier, with this December 24 at 17h WIB a provisional total of 420 dead, more than 1,500 wounded, and 128 missing.

Sources: Sutopo Purwo Negroho and international media.

Java - Joint teams of the Armed Forces, BPBD, Police, and many volunteers continue the search for survivors. - photo BNPB

Java - Joint teams of the Armed Forces, BPBD, Police, and many volunteers continue the search for survivors. - photo BNPB

At Merapi / Java, a lava flow of 300 meters long was observed towards Kali Gendol on 25 December at 0h12 WIB.

The alert level remains unchanged at 2.

Source: BPPTKG

 

Merapi - lava flow 25.12.2018 / 00:12 Wib - Webcam BPPTKG

Merapi - lava flow 25.12.2018 / 00:12 Wib - Webcam BPPTKG

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
 Etna - 24.12.2018 - photo Maria Liotta - via EtNative & Meteo Etna

Etna - 24.12.2018 - photo Maria Liotta - via EtNative & Meteo Etna

From 8:50 am local time, an intense seismic swarm is observed on Etna. During the first three hours, more than 130 earthquakes occurred, the largest of which were of magnitude Ml = 4.0 (at 13:08), located in the area of ​​Piano Pernicana, on the northwestern side of the volcano, 2 km deep and 6 km west. from Zafferana Etnea) and Ml 3.9 (located in the area of ​​Monte Palestra on the NW side of the volcano).

The seismic activity was accompanied by a gradual increase in degassing from the summit crater area, initially with sporadic ash emissions from the Bocca Nuova and the Northeast crater, which ended around 12.00 pm to a dense and continuous plume of black ashes.

After about five minutes, intense Strombolian activity began at the south base of the new south-east crater, probably triggered by an eruptive fissure, and with the opening of several mouths towards Serra Giannicola (flank eruption).
At the same time, Strombolian activity is also increased at Bocca Nuova and Crater Nord-Est.

At 12:01 local time, the Etneo Observatory Office (OE-INGV) issued a Red VONA for the issuance of ashes to the aeronautical authorities.

Geodetic networks, GPS and inclinometers, show obvious deformations of the area of ​​the summit.

Source: INGV Catania

Etna - seismic activity of 24.12.2018 - Doc. INGV Catania
Etna - seismic activity of 24.12.2018 - Doc. INGV Catania

Etna - seismic activity of 24.12.2018 - Doc. INGV Catania

Etna - tremor on 24.12.2018 at 8:10 - INGV Catania

Etna - tremor on 24.12.2018 at 8:10 - INGV Catania

Etna - An eruption for Christmas  - photo J.Nasi / Butterfly Helicopters 24.12.201811h35 GMT

Etna - An eruption for Christmas - photo J.Nasi / Butterfly Helicopters 24.12.201811h35 GMT

Etna - the eruptive fissure on the NSEC flank -  photo J.Nasi / Butterfly helicopters le 24.12.2018 / 11h34 GMT

Etna - the eruptive fissure on the NSEC flank - photo J.Nasi / Butterfly helicopters le 24.12.2018 / 11h34 GMT

Etna - thermal webcam images INGV - RadioStudio7 and LAVE - one click to enlargeEtna - thermal webcam images INGV - RadioStudio7 and LAVE - one click to enlargeEtna - thermal webcam images INGV - RadioStudio7 and LAVE - one click to enlarge
Etna - thermal webcam images INGV - RadioStudio7 and LAVE - one click to enlarge

Etna - thermal webcam images INGV - RadioStudio7 and LAVE - one click to enlarge

Sources: INGV Catania and the different webcams and photographers mentioned

Sunda Strait's Tsunami - Official Flash # 2

Sunda Strait's Tsunami - Official Flash # 2

Last assessment and government communication on the Sunda Strait tsunami:

1. On December 22, 2018, the tsunami hit the coast of Sunda Strait and affected Pandeglang and Serang District in Banten Province, as well as Lampung Selatan, Tanggamus and Pesawaran, districts of Lampung Province. 

2. In five districts, Pandeglang District in Banten Province is the most affected region with 207 dead, 755 wounded, 7 missing and 11,453 displaced (1% out of a total of 1.2 million). An increase in the number of impacts is expected as the evaluation is still ongoing.

3. Indonesian President Joko Widodo traveled to Pandeglang on the morning of 24 December 2018. The priorities of the Indonesian government are coordination, research and development, evacuation, the provision of medical services, the management of internally displaced persons and the restoration of critical facilities.

4. The industrial zones of the Cilegon region have not been affected so far.

5. Local governments lead emergency response efforts in different affected areas.

Thousands of people participate in response operations, consisting of BNPB staff, Provincial and District Disaster Management Authority, Military Indonesia (TNI), Police, Indonesian Search and Rescue Agency (BASRNAS), Ministry of Defense Social Affairs, Ministry of Public Works, Ministry of Health, Ministry of Energy and Mineral resources, NGOs and volunteers. Heavy machinery is mobilized to support research and rescue operations in the affected areas.

6. On the basis of the AHA Center's communication with the BNPB, the tsunami's impact is still within the limits of the national capacities of the Indonesian government. There is no request for international assistance at the moment.

The BMKG issued an official statement on the cause of the tsunami at a press conference at the BMKG office in Jakarta on Monday (24/12). President Joko Widodo examined the site of the tsunami disaster on Monday in Pandeglang, the region with the highest number of casualties and damage.

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Publié dans : #volcanic activity

The latest assessment of the tsunami on December 24 at 19h WIB, still on the rise, mentions 281 dead, more than 1,000 wounded, 57 missing, and 11,687 displaced; the material damage concerns 611 houses, 69 hotels, 60 stalls and shops, 420 boats. (BNPB)

Tsunami report at 24.12.2018 / 22:00 WIB - Doc. BNPB

Tsunami report at 24.12.2018 / 22:00 WIB - Doc. BNPB

Return on the disaster, with the information of the moment:

A particularly violent episode took place on December 22 at 21:03 local, accompanied by an eruptive column more than 16,8 km, according to VAAC Darwin.

The two photos of Øystein Lund Andersen are accompanied by his comment: " I remember being surprised that activity had totally ceased, and Anak-krakatau wasnt even visible at all. No eruption sounds were heard. Then a few minutes passed, and the Tsunami arrived. "

Anak Krakatau - eruption on 22.12.2018 at 19:12 local - photo Øystein Lund Andersen

Anak Krakatau - eruption on 22.12.2018 at 19:12 local - photo Øystein Lund Andersen

Anak Krakatau eruptive site 22.12.2018 at 21:26 WIB - photo Øystein Lund Andersen

Anak Krakatau eruptive site 22.12.2018 at 21:26 WIB - photo Øystein Lund Andersen

The explosion / blast must have dislocated much of the island, causing an aerian collapse (and / or submarine) in the south and southwest areas, which caused the tsunami. The latter could, according to Simon Carn, have been reflected / diffracted by the remains of the caldera, resulting in complex dispersion patterns.

Note that a simulation carried out in 2012 (reference sources) indicated the coastal areas possibly affected by a tsunami following a collapse of the southern flank of Anak Krakatau ... they were actually affected by the tsunami of 22.12. 2018.

Max. waves in the simulation of Giachetti & al. The main cities or important infrastructures possibly impacted around the Strait of La Sonde are indicated by red diamonds BL: Bandar Lampung; K: Kalianda - on Sumatra - M: Merak; A: Anyer; C: Carita; L: Labuhan; P: Panimbang - on Java.

In his conclusions, "the numerical simulation shows that a partial destabilization (0.28 km3) of Anak Krakatau to the southwest could be dangerous at the local level (tourism and fishing activities around the volcano) or even at the regional scale (Sumatran and Java coasts). "

"Due to the large population, the concentration of road and industrial infrastructure along parts of the exposed java and Sumatra coasts, and the low elevation of most of these lands, the tsunami could pose a significant risk. "

"However, as the tsunami travel time is several tens of minutes between the Krakatau archipelago and the main cities along these coasts, a rapid detection of the collapse of the Volcano Observatory, coupled with a system effective warning on the coast, could prevent this hypothetical event from being fatal. "

 

A premonitory tweet of March 2018 by Simon Carn warned again of the potential danger in connection with the constant erection of Anak Krakatau on the edge of the caldera formed by the eruption of 1883.

Anak Krakatau - 23.12.2018 - black cypressoid jets and white plume of steam - Kumparan photos - by Dicky Adam Sidiq uploaded to 16h WIB
Anak Krakatau - 23.12.2018 - black cypressoid jets and white plume of steam - Kumparan photos - by Dicky Adam Sidiq uploaded to 16h WIB

Anak Krakatau - 23.12.2018 - black cypressoid jets and white plume of steam - Kumparan photos - by Dicky Adam Sidiq uploaded to 16h WIB

The eruption of Anak Krakatau continued on 23 December:

Function of the aerial images available (Kumparan - by Dicky Adam Sidiq put on line around 16h WIB), showing black cypressoïdes jets and whites plume of steam, base surges at the base, one can qualify the current phase of the surtseyan type  (see phase of the 1963 eruption that led to the emergence of the island of Surtsey) during which the magma comes out under water, shallow, with significant fragmentation.

We went from a magmatic eruption to a pheatomagmatic eruption.

Anak Krakatau - surtseyan activity from 23.12.2018 - note the collapse scar on the left of the blast on the picture above - and the collapse of the plume generating the blast on the picture below - Grand Carava Susi Air photos via BNPB
Anak Krakatau - surtseyan activity from 23.12.2018 - note the collapse scar on the left of the blast on the picture above - and the collapse of the plume generating the blast on the picture below - Grand Carava Susi Air photos via BNPB

Anak Krakatau - surtseyan activity from 23.12.2018 - note the collapse scar on the left of the blast on the picture above - and the collapse of the plume generating the blast on the picture below - Grand Carava Susi Air photos via BNPB

Vidéo Kumparan

Kompas TV video

A lot of lightning was detected by the WWLLN Lightning strike detection this December 23 : 10,856.

More than 10,000 lightning strikes recorded during the day of 23.12.2018 - Doc. WWLLN Lightning strike detection

More than 10,000 lightning strikes recorded during the day of 23.12.2018 - Doc. WWLLN Lightning strike detection

Summary of the day of December 23 in 2 images: desolation, and power released by the current eruption.

The wave submerged the entire coastline, here in Anyer on 23.12.2018. Doc. EPA-EFE / ADI WEDA

The wave submerged the entire coastline, here in Anyer on 23.12.2018. Doc. EPA-EFE / ADI WEDA

The Kompas front page of this 24.12.2018

The Kompas front page of this 24.12.2018

Sources:

- Kumparan news - https://kumparan.com/@kumparannews/foto-udara-situasi-terkini-gunung-anak-krakatau-1545561798885566899

- Tsunami hazard related to a flank collapse of Anak Krakatau Volcano, Sunda Strait, Indonesia - T. Giachetti, R. Paris, K. Kelfoun and B. Ontowirjo

Geological Society, London, Special Publications, 361, 79-90, 3 January 2012, https://doi.org/10.1144/SP361.7

http://sp.lyellcollection.org/content/361/1/79/tab-figures-data

- PVMBG & BNPB

- photos: Øystein Lund Andersen and Kumparan - by Dicky Adam Sidiq

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Publié le par Bernard Duyck
Publié dans : #volcanic activity

In the Sunda Strait in Indonesia, a tsunami hit both the west coast of Java, facing the volcano Krakatau, and the east coast of Sumatra on December 22 in the evening.

A first announcement is made by Oystein Lund Andersen at 21:15 BST, in vacation at the hotel Anyer. He was busy photographing the erupting Krakatau when he saw a big wave coming ... he ran away, while the wave was passing the beach and engulfed in the land for about twenty meters. A second wave followed, entering the hotel and sweeping cars. He took refuge with his family on the heights by forest roads, and are all safe and sound.

 

Anak Krakatau 22.12.2018 / 19:03 local, about two hours before the tsunami - photo Oystein Lund Andersen

Anak Krakatau 22.12.2018 / 19:03 local, about two hours before the tsunami - photo Oystein Lund Andersen

These devastating waves were not attributed to a tsunami at first, in the absence of characterized seismic signals.

The event is large and the number of victims recorded is growing: at the time of writing, there are at least 168 dead, 30 missing and 745 injured (Sutopo Purwo Nugroho / BNPB); the material balance is also heavy, with more than 500 homes damaged, and roads cut.

West Coast of Java - after the first wave 22.12.2018 - photo Oystein Lund Andersen

West Coast of Java - after the first wave 22.12.2018 - photo Oystein Lund Andersen

The hypothesis of a flank collapse or submarine slide of the Krakatau at the origin of the tsunami must be verified.

A premonitory tweet of March 2018 by Simon Carn warned of the potential danger in connection with the constant erection of the Anak Krakatau on the edge of the caldera formed by the eruption of 1883.

Anak Krakatau - location of its edification on the edge of tne 1883's caldera - Doc. Attached to Simon Carn's tweet in March of this year

Anak Krakatau - location of its edification on the edge of tne 1883's caldera - Doc. Attached to Simon Carn's tweet in March of this year

Images from the Himawari 8 satellite show that ash reached 12-14 km after the eruption; other sources mention a height of 16 km.

A pronounced "cool spot" was observed on infra-red satellite images above the volcano, indicating very high clouds, and a large post-eruptive pyrocumulonimbus.

An update upon receipt of clarification.

To be continued ...

Sunda Strait  - IR image of the Himawari 8 satellite on 23.12.2018 / 00h - to pick up the "cool spot" above the Krakatau

Sunda Strait  - IR image of the Himawari 8 satellite on 23.12.2018 / 00h - to pick up the "cool spot" above the Krakatau

Update : 

A notice from VAAC Darwin this morning

DTG: 20181223 / 0545Z
VAAC: DARWIN
VOLCANO: KRAKATAU 262000
PSN: S0606 E10525
AREA: INDONESIA
SUMMIT ELEV: 813M
ADVISORY NR: 2018/368
SOURCE INFO: HIMAWARI-8
AVIATION COLOR CODE:
RED

Krakatau - Volcanic ash advisory for the 23.12.2018 - Doc. VAAC Darwin

Krakatau - Volcanic ash advisory for the 23.12.2018 - Doc. VAAC Darwin

At 16h WIB, the BNPB revised the tsunami report to the rise: 222 dead, 843 wounded, 28 missing - 556 homes and 9 hotels, 60 food stands and 350 boats damaged.

Sutopo Nugroho warns of the potential threat of another tsunami, with notice in place until Monday. It is important not to be on the beaches around the Sunda Strait, especially during high tides during the full moon.

Tsunami in the Sunda Strait ... a volcanic hypothesis?  - +Update.

Testimony of Tsunami Violence - Indonesian band Seventeen was in concert on Tanjung Lesung beach when the tsunami swept the site, killing the manager and the bass player; four other members of the group are reported missing.

Update - 2

The hypothesis of a collapse of the Krakatau is clear:

A radar image of the Sentinel-1 satellite appears to confirm a partial collapse of the Krakatau cone (and shows concentric waves coming out of the caldera) - via R.Natsuaki / Simon Carn / Twitter.

An aerial photo of Susi Air / Twitter comes in support.

Anak Krakatau - image Sentinel-1 from 22.12.2018 / 22:33 UTC - via R.Natsuaki / Simon Carn / Twitter. - one click to enlarge

Anak Krakatau - image Sentinel-1 from 22.12.2018 / 22:33 UTC - via R.Natsuaki / Simon Carn / Twitter. - one click to enlarge

Anak Krakatau -photo susiair 23.12.2018 - Capt. Mykola from Susi Air  via hudasafiro / Twitter

Anak Krakatau -photo susiair 23.12.2018 - Capt. Mykola from Susi Air via hudasafiro / Twitter

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
 Merapi - dome activity at 21.12.2018 - Doc. BPPTKG

Merapi - dome activity at 21.12.2018 - Doc. BPPTKG

At Merapi on the island of Java, growth of the summit dome continues; On December 19, it reached a volume of 370,000 m³, with an average inflow rate of 2,000 m³ / day, slightly down.

Debris avalanches are reported on 16 and 19 traveling about 300 meters in the indentation.

Yesterday, December 21, a new avalanche of debris would have traveled a greater distance, about 1,000 meters towards the valley of the Gendol River; the distance remains approximate, given the poor visibility conditions.

Source: BPPTKG

Merapi - debris avalanches 16, 19 and 21 December 2018 - Doc. BPPTKG / PVMBG - one click to enlargeMerapi - debris avalanches 16, 19 and 21 December 2018 - Doc. BPPTKG / PVMBG - one click to enlarge
Merapi - debris avalanches 16, 19 and 21 December 2018 - Doc. BPPTKG / PVMBG - one click to enlarge

Merapi - debris avalanches 16, 19 and 21 December 2018 - Doc. BPPTKG / PVMBG - one click to enlarge

Merapi - growth of the dome on 19 December 2018 - Doc. PVMBG

Merapi - growth of the dome on 19 December 2018 - Doc. PVMBG

Karangetang activity, located on the island of Siau north of Sulawesi, has been increasing since the end of November.

These 20 and 21 December, more or less important plumes are visible on the webcam and on photos of premises.

Magma Indonesia reports a level of activity at 3 / siaga, corresponding to new ash emissions, with prohibited zones of 2.5 km radius around the active crater, extended 3 km to the northwest; vigilance is required at the drainage level because of possible lahars, and it is recommended that the requirements for ash emissions be observed.

Source: Magma Indonesia

Karangetang - 20.12.2018 - photo Nia Haerani / Volcano Disaster Support Program

Karangetang - 20.12.2018 - photo Nia Haerani / Volcano Disaster Support Program

Karangetang - 21.12.2018 / 14h59 - photo Magma Indonesia

Karangetang - 21.12.2018 / 14h59 - photo Magma Indonesia

Karangetang - sismogrammes of 20.12.2018 / Nia Haerani / Volcano Disaster Assistance Program - and evolution of seismicity at 21.12.2018 / Magma Indonesia - one click to enlargeKarangetang - sismogrammes of 20.12.2018 / Nia Haerani / Volcano Disaster Assistance Program - and evolution of seismicity at 21.12.2018 / Magma Indonesia - one click to enlarge

Karangetang - sismogrammes of 20.12.2018 / Nia Haerani / Volcano Disaster Assistance Program - and evolution of seismicity at 21.12.2018 / Magma Indonesia - one click to enlarge

Karangetang - map of risk areas reassessed at 21.12.2018 - Doc.Magma Indonesia

Karangetang - map of risk areas reassessed at 21.12.2018 - Doc.Magma Indonesia

An orange aviation code has been assigned to Langila Volcano in Papua New Guinea by VAAC Darwin.

He reports a discreet eruption and ash emission on December 21st from 5:20 pm

VA ADVISORY
DTG: 20181221 / 0027Z
VAAC: DARWIN
VOLCANO: LANGILA 252010
PSN: S0532 E14825
AREA: PAPUA NEW GUINEA
SUMMIT ELEV: 1330M
ADVISORY NR: 2018/47
SOURCE INFO: HIMAWARI-8, VOLCAT
AVIATION COLOR CODE: ORANGE
ERUPTION DETAILS: DISCRETE WILL ISSUE INITIATED AT 20 / 1720Z
OBS VA DTG: 21 / 0027Z
OBS CLD VA: NOT IDENTIFIABLE FM SATELLITE DATA WIND
SFC / FL140 360 / 10KT
FCST CLD VA +6 HR: 21 / 0627Z NO VA EXP
FCST CLD VA +12 HR: 21 / 1227Z NO VA EXP
FCST CLD VA +18 HR: 21 / 1827Z NO VA EXP
RMK: CAN NOT LONGER BE DISCERNED ON SAT IMAGERY, NO OTHER
INFORMATION SOURCES INDICATE THE PRESCENCE OF ASH. ADVISORY
TERMINATED.
NXT ADVISORY: NO FURTHER ADVISORIES

Source: VAAC Darwin

Langila Volcano / PNG - photo by David Gorman / Instagram 25-27.05.2018

Langila Volcano / PNG - photo by David Gorman / Instagram 25-27.05.2018

In Fuego / Guatemala, strong north-easterly winds blow up the ashes emitted by volcanic activity in the Honda dam. Ash falls are reported on San Juan Alotenango, and El Porvenir.

Fuego - ash towards the NE under strong winds - Insivumeh report of 21.12.2018


The VAAC Washington warns against the possibility of greater displacement of ash plumes in this direction.

Sources: Insivumeh & Conred, VAAC Washington

Fuego -20.12.2018 - Remobilization of ash towards the Honda Barranca - photo Conred

Fuego -20.12.2018 - Remobilization of ash towards the Honda Barranca - photo Conred

 Fuego - 21.12.2018 - photo William Chigna, Unity of Prevención de Volcanes -UPV 

 Fuego - 21.12.2018 - photo William Chigna, Unity of Prevención de Volcanes -UPV 

The National Disaster Management Office, the National Emergency Operations Center and the VMGD coordinate their actions in the health, agriculture, water and infrastructure sectors, and develop teams on Ambrym, where new monitoring facilities are installed.

Ash and gas falls were observed on the northeast side of the island; Seismic activity has affected many areas, especially in the southeast, impacting buildings, roads, water supplies and gardens. The most affected village is Pamal; residents moved to Ule School where three evacuation centers are operational.

Help services focuses on the vital needs of shelter, food and drink.

Source: National Emergency Operations Center 19.12.2018

Ambrym - 21.12.2018 - ashes on the sea in Craig Cove Bay on the west of the island - photo Aurelie Bae & Jimmy Bonglipu / Vanuatu Red Cross

Ambrym - 21.12.2018 - ashes on the sea in Craig Cove Bay on the west of the island - photo Aurelie Bae & Jimmy Bonglipu / Vanuatu Red Cross

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Publié le par Bernard Duyck
Publié dans : #volcanic activity

End of the year, it's time for balance sheets.

The first to come out is that of the IGEPN, established by Benjamin Bernard, which summarizes the 2018 volcanic activity in Ecuador and the Galapagos, with respectively two volcanoes erupting in each part of the territory.

Review of the 2018 volcanic activity in Ecuador and Galapagos. - Doc. Ceniza Ecuador blog - Resumen volcanic del 2018 / Benjamin Bernard

Review of the 2018 volcanic activity in Ecuador and Galapagos. - Doc. Ceniza Ecuador blog - Resumen volcanic del 2018 / Benjamin Bernard

In the Galapagos, two volcanoes are to point: Fernandina and Sierra Negra.

After only one hour of seismic activity, a crack opened on the northern flank of Fernandina causing a short-lived eruption, from 16 to 15 June 2018; The lava emitted has reached the sea.

Fernandina - lava fountains on cracks in echelon 16.06.2018 - photo Dr. Marcelo Izquierdo

Fernandina - lava fountains on cracks in echelon 16.06.2018 - photo Dr. Marcelo Izquierdo

Fernandina - lava reaches the ocean on 16.06.2018 - photo Esteban Chavez via Th.toulkeridis

Fernandina - lava reaches the ocean on 16.06.2018 - photo Esteban Chavez via Th.toulkeridis

The seismic unrest lasted more than a year before the Sierra Negra erupted on June 26, 2018, on Isabella Island.

It started on a fissure near the Chico volcano, then spread to the NNW flank; multiple fissures fed several lava flows.

The eruption lasted 57 days, making it the most important eruption for the Galapagos since 1979.

Sierra Negra - fissures and active flows 26.06.2018 - photo Christian Saa - aboard National Geographic Endeavor.

Sierra Negra - fissures and active flows 26.06.2018 - photo Christian Saa - aboard National Geographic Endeavor.

Sierra Negra - eruptive fissures and lava flows between June and August 2018 - Doc. IGEPN

Sierra Negra - eruptive fissures and lava flows between June and August 2018 - Doc. IGEPN

On the continental Ecuadorian territory, both eruptions concern the Reventador and the Sangay.

The Reventador volcano remains the most active volcano in Ecuador, with continued eruptive activity in 2018.

Compared to the previous year, the number of explosions decreased slightly, especially between May and July. This decrease is probably related to the event that occurred in April of this year, a partial collapse of the northwestern part of the summit, probably due to intense explosive activity. This event was followed by the emission of a lava flow that continued until May. There were also pyroclastic flows following the collapse.

Even during a period of relatively low activity, the Reventador is still able to generate problems such as reported ash falls in several areas of the provinces of Imbabura, Napo and Pichincha, associated with relatively high eruptive columns (over 3 km above the crater), including high winds (> 10 m / s) and further west.

 Reventador - eruptive plume and pyroclastic flows 06.04.2018 - IGEPN webcam photo

 Reventador - eruptive plume and pyroclastic flows 06.04.2018 - IGEPN webcam photo

Reventador - sectors modified between 12.04 and 20.06.2018 - Doc. IGEPN

Reventador - sectors modified between 12.04 and 20.06.2018 - Doc. IGEPN

The Sangay (Santiago Moreno) erupted in 2018 between August 8th and December 7th. This eruption was characterized by explosions at the main crater with ash plumes less than 3 km above the crater level, and viscous lava flows from the Ñuñurco dome on the SEE side. Associated with lava flows that have increased about 2 km, small collapses of the flow front have formed small, hot avalanches.

Sangay - seismic activity and number of explosions during the last eruptive phase 16.11.2018 / 11.12.2018 - Doc IGEPN

 

Sangay - on the left, typical ash emission on 18.09.2018 / IGEPN - on the right, ESA image with extension of the lava flows on 24.10.2018 - Doc.via Volcanodiscovery

Sangay - on the left, typical ash emission on 18.09.2018 / IGEPN - on the right, ESA image with extension of the lava flows on 24.10.2018 - Doc.via Volcanodiscovery

Six other volcanoes remain under surveillance of the observatory: Chiles-Cerro Negro, Cayambe, Cuicocha, Guagua Pichincha, Cotopaxi and Tungurahua.

Sources:

- Ceniza Ecuador blog - Resumen volcanic del 2018

- IGEPN

From top to bottom, and from left to right: Chiles-Cerro Negro, Cayambe, Cuicocha, Guagua Pichincha, Cotopaxi and Tungurahua. - photos IGEPN & J.L.Espinosa NaranjoFrom top to bottom, and from left to right: Chiles-Cerro Negro, Cayambe, Cuicocha, Guagua Pichincha, Cotopaxi and Tungurahua. - photos IGEPN & J.L.Espinosa Naranjo
From top to bottom, and from left to right: Chiles-Cerro Negro, Cayambe, Cuicocha, Guagua Pichincha, Cotopaxi and Tungurahua. - photos IGEPN & J.L.Espinosa NaranjoFrom top to bottom, and from left to right: Chiles-Cerro Negro, Cayambe, Cuicocha, Guagua Pichincha, Cotopaxi and Tungurahua. - photos IGEPN & J.L.Espinosa Naranjo
From top to bottom, and from left to right: Chiles-Cerro Negro, Cayambe, Cuicocha, Guagua Pichincha, Cotopaxi and Tungurahua. - photos IGEPN & J.L.Espinosa NaranjoFrom top to bottom, and from left to right: Chiles-Cerro Negro, Cayambe, Cuicocha, Guagua Pichincha, Cotopaxi and Tungurahua. - photos IGEPN & J.L.Espinosa Naranjo

From top to bottom, and from left to right: Chiles-Cerro Negro, Cayambe, Cuicocha, Guagua Pichincha, Cotopaxi and Tungurahua. - photos IGEPN & J.L.Espinosa Naranjo

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
 Etna NSEC - photo 19.12.2018 Boris Behncke

Etna NSEC - photo 19.12.2018 Boris Behncke

Strombolian and effusive activity continues in the growing cone of the "Puttusiddu" of the NSEC / New southeast crater of Etna.

The Bocca Nuova has night glow, and a thermal anomaly always marks three craters: the NSEC, the Bocca Nuova and the northeast.

Sources: Boris Behncke, Joseph Nasi and Sentinel 2

Etna 19.12.2018 - Explosive and effusive activity of the NSEC and incandescence at the Bocca Nuova - photo Boris Behncke

Etna 19.12.2018 - Explosive and effusive activity of the NSEC and incandescence at the Bocca Nuova - photo Boris Behncke

Etna summit  - in the foreground, the NSEC and the "Puttusiddu" - photo J.Nasi / Butterfly helicopters

Etna summit - in the foreground, the NSEC and the "Puttusiddu" - photo J.Nasi / Butterfly helicopters

Etna - thermal anomalies in the 3 now active craters and lava flow of the NSEC - the snow is colored in blue on this image Sentinel2 bands 12,11,4 of 19.12.2018 - one click to enlarge

Etna - thermal anomalies in the 3 now active craters and lava flow of the NSEC - the snow is colored in blue on this image Sentinel2 bands 12,11,4 of 19.12.2018 - one click to enlarge

On Java, the dome of Merapi has a light degassing at about fifty meters above the summit, and a night incandescence, suggesting a tongue of hot debris from the dome towards the crater notch.

At the seismicity level, the PVMBG reports for December 19th, 58 volcanic earthquakes, 14 earthquakes of emission, 6 hybrid earthquakes, and 9 earthquakes of low frequency.

The activity level remains at 2 / wasapada, with a prohibited area of ​​3 km.

Sources: PVMBG, BPPTKG, Magma Indonesia

Merapi - The dome of Merapi degassing 19.12.2018 - photo Whibimardhika (2)

Merapi - The dome of Merapi degassing 19.12.2018 - photo Whibimardhika (2)

Summit and dome of the Merapi 19.12.2018 at 12:30 and 19:00 - the glow seems to mark a debris flow - Doc.BPPTKG
Summit and dome of the Merapi 19.12.2018 at 12:30 and 19:00 - the glow seems to mark a debris flow - Doc.BPPTKG

Summit and dome of the Merapi 19.12.2018 at 12:30 and 19:00 - the glow seems to mark a debris flow - Doc.BPPTKG

In Iceland, an important seismic swarm marks the Herðubreið, a tuya (table mountain) connected to the active volcanic system of the Askja.

The seismic activity started on December 18th at 9:21 am, and is concentrated a few kilometers south-east of the Herðubreið. Approximately 200 earthquakes have been counted since the beginning of activity, most of them under the level of magnitude 3.

They are likely of a tectonic nature (the cause is not formally identified), the Herðubreið being considered extinct, having been formed in a single eruption dated 10-11,000 years ago, towards the end of the last glaciation.

Sources: Icelandic Met Office (IMO) & Iceland review

Herðubreið - seismic swarm at 20.12.2018 / 7:20 - Doc. IMO

Herðubreið - seismic swarm at 20.12.2018 / 7:20 - Doc. IMO

Herðubreið - photo Pietro

Herðubreið - photo Pietro

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