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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
Sheveluch - image Sentinel-2 nat. colors from 28.04.2019 - one click to enlarge

Sheveluch - image Sentinel-2 nat. colors from 28.04.2019 - one click to enlarge

At Sheveluch, in the Kamchatka peninsula, the explosive-extrusive eruption continues.

On April 27, the KVERT reports an ash plume at 4,400 meters asl., drifting southeast over a hundred km.

On April 28, a Sentinel 2 image, taken during clearings, allows to see the hot spots of the summit area and the flows.

The aviation code remains orange, ash explosions can occur at any time.

 

Sources: KVERT & Sentinel 2

Sheveluch - thermal anomalies on 28.04.2019 / 10h55 - Doc. Mirova_MODIS_Latest10NTI

Sheveluch - thermal anomalies on 28.04.2019 / 10h55 - Doc. Mirova_MODIS_Latest10NTI

Sheveluch - hot spots on 28.04.2019 - Sentinel image 2 bands 12,11,4 - one click to enlarge

Sheveluch - hot spots on 28.04.2019 - Sentinel image 2 bands 12,11,4 - one click to enlarge

In Costa Rica, three volcanoes are on alert level 3 / eruption, steady state: Rincon de la Vieja, Turrialba and Poas.

In Poas, inacandescence is observed in the early hours of April 28th; during the morning, a white degassing (majority of steam) continues.

 

Source: Ovsicori

Warning level of Costa Rica volcanoes in 2019 - Ovsicori table
Warning level of Costa Rica volcanoes in 2019 - Ovsicori table

Warning level of Costa Rica volcanoes in 2019 - Ovsicori table

Poas - 28.04.2019 / night glow at 02:39 and degassing at 05:56 - webcam Ovsicori
Poas - 28.04.2019 / night glow at 02:39 and degassing at 05:56 - webcam Ovsicori

Poas - 28.04.2019 / night glow at 02:39 and degassing at 05:56 - webcam Ovsicori

At Merapi, Java, the BPPTKG reports a pyroclastic flow on April 28 at 10:00, for more than two minutes, not observed directly because of the haze.

Seven blast earthquakes and 44 earthquakes of collapses are reported at the PVMBG for the same day.

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

 

Sources: BPPTKG, Magma Indonesia & PVMBG

 Merapi - seismogram of 28.04.2019 - Doc. Magma Indonesia

Merapi - seismogram of 28.04.2019 - Doc. Magma Indonesia

Merapi - summary of the activity of 28.04.2019 / 00-24h WIB - Doc. BPPTKG

Merapi - summary of the activity of 28.04.2019 / 00-24h WIB - Doc. BPPTKG

Some quieter news:

In New Zealand, the period of high temperature that marked the Te Wai crater lake of Ruapehu, as well as the associated volcanic tremor, has passed. During the past week, small plumes of steam have been observed; we can expect a gradual cooling as winter approaches.

The volcanic alert is at level 1, minor instability ... an eruption is likely to occur without or with little warning.

 

Source: GeoNet

Ruapehu - fumaroles on the Te Wai at-moe - picture GeoNet 29.04.2019

Ruapehu - fumaroles on the Te Wai at-moe - picture GeoNet 29.04.2019

In Japan, Sakurajima remains calm for the moment.

Some photos of my friend Pierre Gondolff, on the spot, attest of the situation.

The Sakurajima remains on alert level 2 / do not approach the volcano, established on February 5, 2016 by the JMA

 

Sources: PierreGondolff, whom I thank for sharing photos, and JMA

Sakurajima - Relative calm on 26 and 27.04.2019 - photos © Pierre Gondolff
Sakurajima - Relative calm on 26 and 27.04.2019 - photos © Pierre Gondolff

Sakurajima - Relative calm on 26 and 27.04.2019 - photos © Pierre Gondolff

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
 Popocatépetl - overview of 26.04.2019 - no dome - photo Cenapred / Seguridad / CNPC

Popocatépetl - overview of 26.04.2019 - no dome - photo Cenapred / Seguridad / CNPC

A reconnaissance survey of Popocatépetl was conducted on April 26 by teams from Cenapred and UNAM with the support of the Federal Police. The formation of a new dome was not observed.

During the last 24 hours, 23 exhalations of gas and vapor were recorded; these emanations continued afterwards. A slight nocturnal incandescence was observed.

At the seismicity level, two volcano-tectonic earthquakes are reported with M 2 and 1.7, as well as 50 minutes of low amplitude tremor.

 

Source: Cenapred

Popocatépetl - overview of 26.04.2019 - photo Cenapred / Seguridad / CNPC

Popocatépetl - overview of 26.04.2019 - photo Cenapred / Seguridad / CNPC

The seismicity associated with volcanic activity has increased considerably at the Fuego de Colima, justifying the passage of the volcanic alert to yellow / weak activity, accompanied by an exclusion zone of 8 km around the volcano.

After analysis, two scenarios are proposed:

- the first refers to a moderate explosion, accompanied by the growth of a dome.

- The second possibility is the growth of a dome in the crater and lava overflowing the edge of it on the flanks.

For this reason, it is recommended that citizens respect the exclusion zone and remember that they can carry out their normal activities. However, they must be kept informed of the level of the alert levels and the evacuation procedure. On the other hand, the civil protection authorities continue their permanent work by reinforcing prevention actions in neighboring communities and strengthening their resilience. 

The monitoring of the activity of this volcano is in charge of the University Center of Volcanological Studies of the University of Colima and the University of Guadalajara, under the national coordination of the civil protection.

 

Source: Civil Protection Colima & Univ. From Colima

Colima - the summit crater on 27.01.2018 / photo Jalisco State Civil Protection and Fire Department.

Colima - the summit crater on 27.01.2018 / photo Jalisco State Civil Protection and Fire Department.

In the past week, at Turrialba / in Costa Rica, activity remained low and stable. The LP earthquake record is maintained however.

On 27 April at 7:22, the Turrialba had a short, short eruption, accompanied by a small plume of brown ash that rose 100 meters above the summit.

Note on April 23 at 21:08, the passage of a meteorite could be observed on the webcams of Poas and Turrialba towards SE-NO (https://www.facebook.com/OVSICORI/videos/433337287423565/)

 

Source: Ovsicori

Turrialba - 27.04.2019 / 07:22 - ash emission - webcam Ovsicori

Turrialba - 27.04.2019 / 07:22 - ash emission - webcam Ovsicori

In the Philippines, rock falls and moderate vapor emissions have been observed in Mayon since the middle of the month.

A 25 April Sentinel2 image shows hot spots in the crater and two separate plumes.

On April 27th, Phivolcs reports two volcanic earthquakes and five rock falls.

 

Sources: Phivolcs & Sentinel 2

 Mayon - hot spots and 2 distinct plumes on the image Sentinel-2 image bands 12,11,4 of 25.04.2019 - one click to enlarge.

 Mayon - hot spots and 2 distinct plumes on the image Sentinel-2 image bands 12,11,4 of 25.04.2019 - one click to enlarge.

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologie
 Etna Northeast - 26.04.2019 / 18h39 - INGV thermal webcam
 Etna Northeast - 26.04.2019 / 18h39 - INGV thermal webcam

Etna Northeast - 26.04.2019 / 18h39 - INGV thermal webcam

An explosion occurred at the north-eastern crater of Etna on April 26 at 18:39, accompanied by an ash emission towards Linguaglossa. Small falls of ash are reported.

The NE crater did not show much since the collapse of its southwestern edge on February 22nd.

 

Sources: INGV webcam and commentary by Boris Behncke

Tenerife - seismicity from 24 to 26.04.2019 - Doc. IGN.es

Tenerife - seismicity from 24 to 26.04.2019 - Doc. IGN.es

A series of small earthquakes have been recorded in the southern ridge of Tenerife; the last of magnitude 0.7 and 1.4 at a depth of 8.4 and 8.8 km.

The alignment with the volcanic cones, and the fact of the seismicity unfolding in an area where they are infrequent, call out.

Historically, the last eruptions in Tenerife begin with a seismic sequence in the Valle de la Orotava ... and this makes us think about the fissure eruption of 1430 which lasted about thirty days.

To watch, despite the green semaphore of PEVOLCA.

 

Sources: IGN es - Involcan - Pevolca

 Tenerife - Valle de La Orotava - Doc. IGN.es

Tenerife - Valle de La Orotava - Doc. IGN.es

Tenerife - information on the seismic-volcanic activity of Tenerife - Doc. Guayota - Pevolca

Tenerife - information on the seismic-volcanic activity of Tenerife - Doc. Guayota - Pevolca

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
Dukono - activity of January 2019 - photo Magma Indonesia

Dukono - activity of January 2019 - photo Magma Indonesia

The eruption continues on Halmahera, where the Dukono presented, this April 25, four eruptive episodes, underlined by earthquakes and continuous tremor dominant amplitude to 2 mm.

The PVMBG reports plumes at a height of 100-200 meters above the summit.

The activity level is 2 / waspada, with a 2 km radius prohibited area around the Malupang Warirang crater.

 

Source: PVMBG

Dukono- Volcanic ash advisory for the 26.04.2019 - Doc. VAAC Darwin IDY65290

Dukono- Volcanic ash advisory for the 26.04.2019 - Doc. VAAC Darwin IDY65290

In the past 24 hours, Cenapred has identified 16 exhalations at Popocatépetl, with water vapor, gas and small amounts of ash.

Nighttime glow is observed at the same time as the most important exhalations.

The seismicity is characterized by 318 minutes of tremor of very low amplitude, and by a volcano-tectonic earthquake of M1,4.

On the 25th in the morning until 16h, the constant emission of a plume of gas, vapor and ashes is observed, dispersed towards the east.

The volcanic alert remains at Amarillo fase 3.

 

Source: Cenapred

Popocatépetl - exhalation of 24.04.2019 - photo Cenapred

Popocatépetl - exhalation of 24.04.2019 - photo Cenapred

The structure of the Lō'ihi submarine volcano in Hawaii, and the morphology of lava flows has been mapped by the MBARI / Monterey Bay Aquarium Reseach Institute.

This young submarine volcano began to manifest itself a hundred thousand years ago.

A nested series of caldera collapses and craters was observed at the summit, the rising of a resurgent block, and eruptions that formed at least five low lava shields. The oldest and largest caldera, formed about 5900 years ago, covers almost the entire summit plateau. The resurgent block was raised a little over 100 m and has a sloped surface with a dip of about 6.5 ° towards the SE.

 Lō'ihi Submarine Volcano, Hawaii - Study Area - Doc. in Structure of Lō'ihi Seamount, Hawai'i and Lava Flow Morphology from High-Resolution Mapping / References in Sources

 Lō'ihi Submarine Volcano, Hawaii - Study Area - Doc. in Structure of Lō'ihi Seamount, Hawai'i and Lava Flow Morphology from High-Resolution Mapping / References in Sources

It was later modified by the collapse of a crater centered in the block that formed West Pit. The shallowest point on the Lō'ihi summit has a depth of 986 m and lies at the northwestern limit of the resurgent block.

The final collapse formed the Pelé Trench in 1996. The nine mapped collapse and resurgent structures indicate the presence of a shallow crustal magmatic chamber ranging from 1 km to perhaps 2.5 km deep and demonstrate that shallow sub-caldera magma reservoirs exist during the last pre-shield stage. In the deep south rift zone, there are young medium to high flow lava flows that probably erupted in 1996 and drained the shallow crustal magmatic chamber to trigger the collapse that formed the Pele's Trench.

Summit bathymetry with interpretive overlay of caldera and pit crater bounding scarps. Sentry data in foreground with Simrad EM302 data behind. Hatchures indicate down-thrown side of caldera or pit crater bounding scarps or ring faults R1 (oldest) to R9 (youngest). Exact sequence of formation for some collapse events cannot be determined. P-A to P-D are pit craters described in the text and in Table 1. EP is East Pit, WP is West Pit, PP is Pele’s Pit, C1 to C3 indicate two cones described in the text, S1 to S5 indicate the remnants of five lava shields, B indicates 1996 basaltic breccia, and V indicates volcaniclastic sediment 5–11 m thick (Clague et al., 2003; Schipper and White, 2010) with a basal date of ∼5900 years (Clague, 2009). Arrow labeled “flow” indicates direction of channelized flow from S1 to the east.

Summit bathymetry with interpretive overlay of caldera and pit crater bounding scarps. Sentry data in foreground with Simrad EM302 data behind. Hatchures indicate down-thrown side of caldera or pit crater bounding scarps or ring faults R1 (oldest) to R9 (youngest). Exact sequence of formation for some collapse events cannot be determined. P-A to P-D are pit craters described in the text and in Table 1. EP is East Pit, WP is West Pit, PP is Pele’s Pit, C1 to C3 indicate two cones described in the text, S1 to S5 indicate the remnants of five lava shields, B indicates 1996 basaltic breccia, and V indicates volcaniclastic sediment 5–11 m thick (Clague et al., 2003; Schipper and White, 2010) with a basal date of ∼5900 years (Clague, 2009). Arrow labeled “flow” indicates direction of channelized flow from S1 to the east.

Pele's Pit crater near the top of Lo'ihi Seamount - yellow iron-iron-laden lava and microbial mats - photo Nautilus Live 29,08,2018

Pele's Pit crater near the top of Lo'ihi Seamount - yellow iron-iron-laden lava and microbial mats - photo Nautilus Live 29,08,2018

These channeled and hummock flows have molten nuclei, and currently harbor the FeMO hydrothermal field.

The Deep Shinkai Hydrothermal Site is located in the steep-walled, lumpy flows that formed during low flow eruptions. Shinkai Ridge is most likely a coherent landslide block that originated on Lōihi's east flank.

 

Sources:

- MBARI - Mapping the next Hawaiian island

- Frontiers of Earth Sciences - Structure of Lō'ihi Seamount, Hawai'i and Lava Flow Morphology from High-Resolution Mapping by David A. Clague, Jennifer B. Paduan, David W. Caress, Craig L. Moyer, Brian T. Glazer and Dana R. Yoerger. (Creative Commons License Attribution (CC BY))

Shinkai Deep Hydrothermal Center and Shinkai Ridge - AUV Sentry bathymetry showing the combined map of 266 missions and 270 at Shinkai Deep hydrothermal site (near center) and during missions 267 and 269 at Shinkai Ridge (upper right). Figure 9. The data are gridded at 2 m.

Shinkai Deep Hydrothermal Center and Shinkai Ridge - AUV Sentry bathymetry showing the combined map of 266 missions and 270 at Shinkai Deep hydrothermal site (near center) and during missions 267 and 269 at Shinkai Ridge (upper right). Figure 9. The data are gridded at 2 m.

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Publié le par Bernard Duyck
Publié dans : #volcanic activity

An update on the state of volcanoes in Vanuatu : five volcanoes remain on alert level 2.

Volcanic troubles continue in Gaua. Volcanic activity is expected to remain at similar levels, consistent with Level 2 Volcanic Warning. The danger zone for the safety of people is limited to the volcanic cone.

The activity consists of a current volcanic vapor cloud that may contain volcanic gases. The gas will continue to feel as the volcanic cone approaches.

Alert level for volcano Gaua is at level 2 since January 31, 2018.

Gaua - Nasa Space Shuttle archive photo

Gaua - Nasa Space Shuttle archive photo

Volcanic ash that fell on Ambae during the 2017 and 2018 eruptions could continue to alter the behavior of creeks and streams when it rains. Streams and streams can produce floods and carry a lot more debris (sands, gravel and rocks). The flow path of creeks and streams may change due to flood debris. A landslide can occur in some areas during heavy rainfall.

The latest observations and analyzes of the seismic data recorded by the monitoring station confirm that the activity of the volcano is in the state of major disorders (level 2). Volcanic activity consists of the continuous emission of steam and / or other volcanic gases. Villages exposed to prevailing winds could expect to find deposits of volcanic ash falls and smell volcanic gases.

Alert level for Ambae has been at level 2 since 21 September 2018.

Vanuatu - Ambae / Manaro voui - zoom in the image Sentinel 2 bands 4,3,1 - one click to enlarge

Vanuatu - Ambae / Manaro voui - zoom in the image Sentinel 2 bands 4,3,1 - one click to enlarge

On April 24, the Vanuatu Meteorological and Geo-Risk Department (VMGD) reported on seismic activity and steam emissions at Ambrym .

The lava lakes of the Benbow and Marum craters had ceased to be active on December 16, 2018, one day after the beginning of a crack eruption in the ESE portion of the summit caldera near the Lewlembwi crater, and continued to be inactive.

The alert level remained at 2 (on a scale of 0 to 5); the report reminded the public to stay outside the zone of permanent danger defined by a radius of 1 km from the crater Benbow and 2 km from the crater Marum. An additional danger zone was defined as a radius of 1 km around the December 2018 cracks.

Ambrym - transversal section W-E - Doc. VGO 15.12.2018

Ambrym - transversal section W-E - Doc. VGO 15.12.2018

The activity of the Lopevi volcano is unstable in the state of major troubles. In the current state of things, volcanic activity is likely to increase at any time, but it could also remain at the same level for a long time. The danger zone for the safety of people is limited to the island.

Current observations and seismic analyzes recorded from the monitoring network confirm a still very active volcanic activity in level 2. The activity continues to occur in active craters near the crater of the summit and consists of continuous emissions of steam. and other gases.

Lopevi drumplot - 24.04.2019 - Doc. VGO

Lopevi drumplot - 24.04.2019 - Doc. VGO

Instability continues in Yasur on Tanna Island. Volcanic activity is expected to remain at the same level, in accordance with Level 2 Volcanic Warning; the danger zone remains at 395 m around the eruptive vents. The danger zone for life is limited in the permanent exclusion zone.

The latest observations and analyzes of the seismic data recorded from the monitoring network confirm a continuous volcanic activity in the level of major agitation and confined in the crater. The activity consists of explosions in progress. Some explosions remain intense and volcanic bombs may fall in and / or around the crater. Eruptive vents can emit volcanic gases and / or ash clouds. The gas will continue to feel as you approach the caldera and crater.

 

Source: Vanuatu Geohazards Observatory - newsletter n ° 4 / 24.04.2019

Vanuatu - Yasur - 25.04.2019 / 17:45 local - VGO webcam

Vanuatu - Yasur - 25.04.2019 / 17:45 local - VGO webcam

Yasur drumplot of 24.04.2019 - Doc. VGO

Yasur drumplot of 24.04.2019 - Doc. VGO

In Kilauea, the summit area continues to stabilize after a number of collapses and tens of thousands of earthquakes that rocked it last year.

On April 25, a significant fall of rocks was observed from the Volcano house, under the Jaggar museum and the HVO site unoccupied.

Some parts of the National Park are open, others remain prohibited because of the danger or the disappearance / bad condition of the trails. Specific information from: https://www.nps.gov/havo/20190419_recovery_faq.htm

 

Source: National Park Service

Kilauea summit - 25.04.2019 - significant drop of rocks has been observed since the Volcano house, under the Jaggar museum and the site of the HVO unoccupied. - photo NPS / Janice Wei

Kilauea summit - 25.04.2019 - significant drop of rocks has been observed since the Volcano house, under the Jaggar museum and the site of the HVO unoccupied. - photo NPS / Janice Wei

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologie
Sheveluch - Copernicus image from 13.04.2019 - one click to enlarge

Sheveluch - Copernicus image from 13.04.2019 - one click to enlarge

The explosive-extrusive eruption of Sheveluch continues: on April 23, the KVERT reports an ash plume at 4,000-4,500 meters asl, drifting northeast over 50 km.

Copernicus shows a thinning on the top of the volcano, which allows to see the infra-red signature of ongoing lava flow.

Moderate thermal anomalies are recorded by Mirova, of VRP between 13 and 69 MW.

 

Source: KVERT

 Sheveluch - image Sentinel-2 nat Colors from 23.04.2019

 Sheveluch - image Sentinel-2 nat Colors from 23.04.2019

Sheveluch - thermal anomalies on 24.04.2019 / 01h55 - Doc. Mirova_MODIS_Latest10NTI

Sheveluch - thermal anomalies on 24.04.2019 / 01h55 - Doc. Mirova_MODIS_Latest10NTI

In Taal, in the Philippine archipelago, the number of volcanic earthquakes is maintained in recent days to about 10 daily episodes.

The Phivolcs recorded for April 20 : 11 episodes, for April 21: 9 episodes, for April 22 : 10 episodes and for April 23 : 9 episodes.

For field measurements, refer to those of 18 April.

The alert level remains within the scope of the Level 1 / Non-imminent hazardous eruption.

Philippines - earthquake on the island of Samar - Doc. Phivolcs earthquakes

Philippines - earthquake on the island of Samar - Doc. Phivolcs earthquakes

Note that a series of earthquakes hits the Philippines. Among the most important, an earthquake of magnitude 6.1 on 22 April on Castillejos / Zambales is responsible for 11 dead and many wounded; another of magnitude 6.4 on April 23, on the island of Samar, stands out among many aftershocks

 

Source: Phivolcs

Zavodovski island - Earthquake M6,0 on 22.04.2019 / 14:49 UTC depth 100 km - Doc. EMSC

Zavodovski island - Earthquake M6,0 on 22.04.2019 / 14:49 UTC depth 100 km - Doc. EMSC

A magnitude 6.0 earthquake was recorded on April 22, 2019 at 14:49 UTC, and a depth of 100 km in the South Sandwich Islands, near Zavodovski Island.

This island is constituted by a basaltic stratovolcano, Mount Curry, decentered towards the west; two cracks extend on the eastern flanks and a lava platform is located on the east coast.

Its first eruption was observed in 1819, and the last activity dates from 2016 (30,03,2016 - 16,05,2016)

 

Source: EMSC

 The South Sandwich Islands volcanic arc - Doc. Google Earth - one click to enlarge

 The South Sandwich Islands volcanic arc - Doc. Google Earth - one click to enlarge

Zavodovski island - image Sentinel-2 nat. colors from 14.04.2019 - one click to enlarge

Zavodovski island - image Sentinel-2 nat. colors from 14.04.2019 - one click to enlarge

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
 Agung - 21.04.2019 / 3:21 Wita - photo S.Purwo Nugroho

Agung - 21.04.2019 / 3:21 Wita - photo S.Purwo Nugroho

Agung - 21.04.2019 / 06h34 - Doc. Telkom 3:34

Agung - 21.04.2019 / 06h34 - Doc. Telkom 3:34

Two eruptive episodes marked the Agung in Bali on April 21st:

- the first, at 3:21 WITA, it was accompanied by a plume of gray ash and thick at 2,000 meters above the summit, inclined to the southwest; recording on the seismogram lasted 2 minutes 55 seconds, with a maximum amplitude of 25 mm.

- The second episode at 18:55 WITA, accompanied by a plume of ash at 3,000 meters above the crater, lasted 1 minute 22 seconds.

Seismicity is dominated by earthquakes reflecting fluid movements in depth and close to the surface. The lava dome remains relatively unchanged since the eruptive period 2017-2018, with about 25 Mm³, corresponding to 40% of the volume of the empty crater.

The ash cloud did not affect Ngurah Rai airport.

The activity level remains at 3 / siaga, with a forbidden area of ​​4 km radius.

 

Sources: PVMBG & BNPB

Agung -sismogram of 21.04.2019 - Doc.MAgma Indonesia

Agung -sismogram of 21.04.2019 - Doc.MAgma Indonesia

Agung - 21.04.2019 / 19:18 - photo Telkom; Ash drift to the southeast while sparing the airport - Doc. BMKG / Himawari 21.04.2019 / 21:20 - a click to open and enlargeAgung - 21.04.2019 / 19:18 - photo Telkom; Ash drift to the southeast while sparing the airport - Doc. BMKG / Himawari 21.04.2019 / 21:20 - a click to open and enlarge

Agung - 21.04.2019 / 19:18 - photo Telkom; Ash drift to the southeast while sparing the airport - Doc. BMKG / Himawari 21.04.2019 / 21:20 - a click to open and enlarge

At Merapi on Java, the BPPTKG reported for this April 21, between 6am and 6pm WIB, three avalanches of blocks towards Kali Gendol, with respective lengths of 600,800 and 1,100 meters. The status remains at 2 / waspada.

 

Source: BPPTKG

 Merapi - Avalanche of blocks generating a pyroclastic flow on 21.04.2019 / 06h WIB - Doc. Merapi news

 Merapi - Avalanche of blocks generating a pyroclastic flow on 21.04.2019 / 06h WIB - Doc. Merapi news

The activity of Sakurajima in Japan continues with e.a. eruptive episodes, this April 22 at 9:08 local, accompanied by a plume at 1,300 meters above the crater.

Another episode is reported at 1:15 pm, with a plume 800 meters above the crater Minamidake.

Ash falls are expected in the cities of Kagoshima, Satsuma Kawachi, Kirishima and Aira

 

Source: JMA

Sakurajima - 22.04.2019 / 9:10 - Doc. JMA

Sakurajima - 22.04.2019 / 9:10 - Doc. JMA

The activity of Klyuchevskoy is rising, characterized by emissions of gas and steam containing ashes since April 8.

On 21 April, the KVERT reports in its end-of-day bulletin, an increase in the quantities of ashes emitted, and a plume at 5.500 meters drifting eastward for 130 km.

The aviation code remains orange.

Klyuchevskoy - Volcanic ash advisory for 21-22.04.2019 - Doc. VAAC Tokyo

Klyuchevskoy - Volcanic ash advisory for 21-22.04.2019 - Doc. VAAC Tokyo

Explosive - extrusive activity continues at Sheveluch, with a plume of ash at 3,500-3,800 meters in height, drifting eastward for 70 km.

The aviation code remains orange.

 

Sources: KVERT, VAAC Tokyo, Sentinel 2 and Landsat.

Sheveluch -image Sentinel-2 Penetration Atmosph. of 20.04.2019

Sheveluch -image Sentinel-2 Penetration Atmosph. of 20.04.2019

Sheveluch-picture Landsat 8 OLI / Nasa from 19.04.2019

Sheveluch-picture Landsat 8 OLI / Nasa from 19.04.2019

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 Nevado del Ruiz - photo OBS Sostenibilidad 18.04.2019

Nevado del Ruiz - photo OBS Sostenibilidad 18.04.2019

During the past week, Nevado del Ruiz has experienced various episodes of explosive ash emissions, with plumes of variable height, between 230 and 1,300 meters; these emissions were concomitant with pulsatile tremor and LP low energy earthquakes.

Most of the ash has been dispersed to the north-west and south-east of the volcano, and further falls of ash are expected.

The level of activity is maintained at 3-yellow / behavioral changes of volcanic activity.

 

Source: Servicio Geologico Colombiano / 18,04,2019

Etna - hot spots on the image Sentinel-2 image bands 12,11,4 of 18.04.2019 - one click to enlarge

Etna - hot spots on the image Sentinel-2 image bands 12,11,4 of 18.04.2019 - one click to enlarge

In the past few weeks, we can observe at Etna thermal anomalies that remain low, between 1 and 4 MW, corroborated by the satellite images of the hot spots at the summit.

They correspond to the Bocca Nuova and the eastern mouth of the NSEC.

" Magma is reoccupying the central ducts, very similar to what was observed last summer ", commented Boris Behncke.

 

Sources: Boris Behncke, Mirova and Sentinel 2

Etna - thermal anomalies on 20.04.2019 / 01h05 - Doc. Mirova_MODIS_Latest10NTI

Etna - thermal anomalies on 20.04.2019 / 01h05 - Doc. Mirova_MODIS_Latest10NTI

In the Aeolian Islands, Stromboli exhibits activity that fluctuates between low and moderate levels, with explosions averaging a few minutes apart from various vents on the crater terrace.

Most occur at the northeastern vent and the westernmost vent, which eject incandescent materials at 80 - 150 m. above. The westernmost vent has strombolian explosions rich in ash.

Mirova reports low to moderate thermal anomalies on April 19 and 20, VRP between 2 and 23 MW

 

Sources: Volcanodiscovery, Mirova and Sentinel 2

 Stromboli - successive puffs on 18.04.2019 - image Sentinel-2 nat colors - one click to enlarge

Stromboli - successive puffs on 18.04.2019 - image Sentinel-2 nat colors - one click to enlarge

Stromboli - eruption of the west vent on 19.04.2019 on the Pizzo / INGV thermal camera Catania

Stromboli - eruption of the west vent on 19.04.2019 on the Pizzo / INGV thermal camera Catania

  Stromboli - thermal anomalies on 20.04.2019 / 01h05 - Doc. Mirova _MODIS_Latest10NTI

Stromboli - thermal anomalies on 20.04.2019 / 01h05 - Doc. Mirova _MODIS_Latest10NTI

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Bromo Volcano Time Lapse for 2019-04-17 : A really active day

In Bromo, on the island of Java, ash emissions continue, justifying an orange VONA.

On April 17, the plumes, sometimes white, sometimes black, more or less laden with ashes, rose to a maximum height of 500 meters. The seismicity is characterized by a continuous tremor of dominant amplitude of 1mm., And by a deep volcanic earthquake.

On April 18, the parameters remain the same, except the height of the plume at max 300 meters.

The alert remains at 2 / waspada, with a prohibited area of ​​1 km.

 

Source: PVMBG

Lake Taal and Taal Volcano - photo Rove.me

Lake Taal and Taal Volcano - photo Rove.me

In the Philippines, the Phivolcs recorded 7 volcanic earthquakes in Taal on 18 April.

Field measurements on April 18, in the western sector of the main crater lake, reveal an increase in water temperature from 31.3 °C to 32.8 °C, a decrease of water level from the 34 cm to 25 cm, and a strong acidity. Low inflation is also observed thanks to the GPS network.

Daily volcanic earthquakes began in Taal on March 28, 2019.

Alert level remains at 1; an eruption not being imminent.

 

Source: Phivolcs

Ushkovsky - photo volcanoesland

Ushkovsky - photo volcanoesland

A volcanic ash dispersal simulation exercise took place between VAAC Tokyo, Kvert via the Himawari - 8 satellite, on April 18-19, targeting Ushkovsky and Opala volcanoes in Kamchatka.

 

Simulation for Ushkovsky:

A strong explosive eruption occurred at Ushkovsky volcano from 22:15 UTC this April 18, the ash ejected reached a height of 7,600 meters before drifting to the northwest on 30 km. The aviation alert has changed from green to Red.

The aviation alert was reviewed on April 18 at 23:30 UTC: orange, then returned to green on April 19 at 0:23 UTC.

Opala - photo Leopold Sulerzhitsky (Holocene Kamchataka volcanoes) via GVP

Opala - photo Leopold Sulerzhitsky (Holocene Kamchataka volcanoes) via GVP

Simulation for Opala:

A very strong explosive eruption began at 9:45 pm on April 18 at Opala volcano, which produced an ash plume at an altitude of 13,800 meters asl, drifting southeast 50 km.

The aviation code changed from green to red at 22:00 UTC on April 18, before being seen again on April 18 at 23:00 UTC, then back to green on 19 April at 02:20 UTC.

 

These simulations, WITHOUT ANY ERUPTION, besides the allowed calibrations, put these volcanoes in light. The last eruption of the stratovolcano Opala dates back to 1.776 (see GVP - http://volcano.si.edu/volcano.cfm?vn=300080)

As for the Ushkovsky, a large volcanic massif, formed by the Ushkovsky / ex. Plosky, of his two intracanalic cinder cones, and Krestovsky, his last eruptive activity dates from 1890 (see GVP - http://volcano.si.edu/volcano.cfm?vn=300261)

 

Sources: KVERT & VAAC Tokyo - Global volcanism Program

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
Dukono - long plume looking east on this image Sentinel-2 image IR bands 8.4,3 from 16.04.2019 - one click to enlarge

Dukono - long plume looking east on this image Sentinel-2 image IR bands 8.4,3 from 16.04.2019 - one click to enlarge

 Dukono - Volcanic ash advisory for 17-18.04.2019 - Doc. VAAC Darwin

Dukono - Volcanic ash advisory for 17-18.04.2019 - Doc. VAAC Darwin

At Dukono, on the island of Halmahera, there are continuous eruptions.

The VAAC Darwin reports the emission on April 10-12 and April 15-16 of ash plumes rising up to 2,400 meters asl before dispersing according to the direction of the wind.

The alert level remains at 2 / waspada, with a 2 km exclusion zone around the Malupang Warirang crater; the VONA has been in orange since April 12, following the emission of an ash plume at 1,900 meters asl. approximately (600 meters above the crater)

 

Sources: VAAC Darwin, Sentinel 2 & Magma Indonesia

Dukono -summary of seismicity on 17.04.2019 - Doc. Magma Indonesia

Dukono -summary of seismicity on 17.04.2019 - Doc. Magma Indonesia

The activity of Turrialba between 2010 and 2018 mainly affected populations around the greater metropolitan area.

According to reports from individuals on the social networks and the scientific reports of the Ovsicori and the RSN, between 8 and 9 million cubic meters of ash were expelled, of which 87% on some parts of the big metropolis, of which Curridabat, San Pedro de Montes de Oca, Moravia, Goicoechea and Coronado.

These ashes impact the air traffic, with 373 flights disrupted or canceled.

Turrialba - The isofrequency data revealed that out of 123 villages that reported an ashfall, between 2010 and 2017, 68 are located in 29 cantons belonging to the metropolitan area. - Doc. University of Costa Rica

Turrialba - The isofrequency data revealed that out of 123 villages that reported an ashfall, between 2010 and 2017, 68 are located in 29 cantons belonging to the metropolitan area. - Doc. University of Costa Rica

Since late 2017, no volcanic activity has been reported, and the National Park could be reopened to visitors this year; the restriction zone is within a radius of 2-3 km, increased to 5 km in case of intensification of activity.

 

Source : Universidad de Costa Rica

 Turrialba - the active crater - photo Univ. Costa Rica / Pablo Ruiz - 17.04.2019.

 Turrialba - the active crater - photo Univ. Costa Rica / Pablo Ruiz - 17.04.2019.

GeoNet / GNS scientists' observations show that Whakaari / White island's activity level is not substantially altered, and corresponds to Alert Level 1 and the Green Aviation Code.

White island - photo GNS 04.2019

White island - photo GNS 04.2019

The temperature of the crater lake has risen to more than 60 °C, with many fumaroles contributing to the high temperature. The temperature of the strongest accessible fumarole remains around 120-130 °C. The dome area, west side of the crater, remains under water.

Seismicity in the 10-50 km around the volcano is high, but the volcanic tremor remains low.

The flow of sulfur dioxide, an indicator of magmatic movements, remains in the norms of previous years.

White island - new vent on 30.04.2016 - photo GeoNet

White island - new vent on 30.04.2016 - photo GeoNet

The current crater lake at Whakaari / White Island was formed following an eruption in April 2016 that removed the present lake and dug the bottom of the crater by about 13 meters. Major crater lakes have formed 4 times over the past 16 years, but have never reached the overflow. In February-March 2006, the lake level was one meter above the overflow level, before retiring due to warming and evaporation. An overflowing lake would impact the bottom of the crater and potentially the dynamics of the hydrothermal system.

It is now unlikely to happen because since the end of January 2019, the lake's water level has been declining.

 

Source: GeoNet / GNS

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