Overblog
Suivre ce blog Administration + Créer mon blog

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

A small explosion occurred this June 1 at 10:32 am AKST at the Cleveland volcano in the Aleutians; it was detected by the infrasonic surveillance network, the local surveillance stations being offline

It was accompanied by a small plume of ash observed at more than 6,000 meters asl. drifting south. Aviation code is orange

 

Source: AVO / Alaska volcano Observatory

Cleveland - Clear Worldview-3 satellite image of the summit crater and lava dome, April 30, 2020 - Digital Globe image via NextView License / Matt Loewen / in AVO

Cleveland - Clear Worldview-3 satellite image of the summit crater and lava dome, April 30, 2020 - Digital Globe image via NextView License / Matt Loewen / in AVO

Two eruptive episodes marked Rincon de La Vieja in Costa Rica on June 1st.

The first, at 5 p.m., produced a plume reaching 1,500 to 2,000 meters above the summit; for the second at 5:45 pm, the height of the plume was 2,000 meters, and the duration of one minute. No ash fall or sulfur odor was associated with these eruptions.

On June 2, from 5 to 7.15 am, activity was constant. It continues with a beautiful white plume emitted at 3:47 p.m. local time.

The volcanologist Javier Pacheco specifies that an overview of the volcano is necessary to check the changes to the crater. Day after day, the conduits open and the activity of the volcano changes, with an increase in daily events.

 

Sources: Ovsicori and interview in Nacion

 Rincon de la Vieja - hydrothermal eruption of 01.06.2020 / 1705 - Doc. Ovsicori video clip

Rincon de la Vieja - hydrothermal eruption of 01.06.2020 / 1705 - Doc. Ovsicori video clip

The Geophysical Institute of Peru (IGP) reports that the eruptive activity of the Sabancaya volcano remains at moderate levels, with the continuous recording of 14 explosions per day on average, with plumes up to 2 km in height on the summit of the volcano, and consequent emissions of ash and gas, dispersed towards the east and southeast sectors of the volcano.

The IGP recorded and analyzed the occurrence of approximately 414 earthquakes of volcanic origin, associated with the circulation of fluids (magma, gas, etc.) within the volcano

The monitoring of the deformation of the volcanic structure, using GNSS data (processed with fast orbits), does not present any significant anomalies; however, since May 23, there has been slight inflation of the southeast flank and the northern sector of Sabancaya, probably related to the eruptive activity of the volcano.

Satellite surveillance has identified the presence of 8 thermal anomalies of values ​​between 2 MW and 15 MW, associated with the presence of a body of lava on the surface of the crater of the volcano.

The level of volcanic alert remains orange, with prohibition to approach within a radius less than 12 km from the crater.

 

Source / I.G. Peru

Sabancaya - summary of the activity between 25 and 31 May 2020 - Doc. I.G.Peru

Sabancaya - summary of the activity between 25 and 31 May 2020 - Doc. I.G.Peru

A particularly calm month of May 2020 in Piton de la Fournaise with the end of inflation, low seismicity, with less than one earthquake per day recorded under the summit craters and a decrease in the flow of CO2 into the soil in the field distant.

Piton de La Fournaise: Comparison between the normalized means of CO2 flux data in the soil, raw (averaged over a 15-day sliding window, in green) and corrected (in black), recorded at stations located in the far field from October 2016 (date of installation of the last station). Eruptive periods are shown in red and intrusive periods in gray (© OVPF-IPGP).

Piton de La Fournaise: Comparison between the normalized means of CO2 flux data in the soil, raw (averaged over a 15-day sliding window, in green) and corrected (in black), recorded at stations located in the far field from October 2016 (date of installation of the last station). Eruptive periods are shown in red and intrusive periods in gray (© OVPF-IPGP).

The replenishment of magma and the pressurization of the surface magmatic reservoir which had resumed following the end of the eruption of 2-6 April ceased at the end of April.

Note that since 2016, the replenishments of the surface magmatic reservoir under the Piton de la Fournaise have been carried out by impulses, so such phases of lull in deformations and seismicity have already been observed several times between 2016 and 2019 over periods ranging from about 15 to 80 days.

The alert level is vigilance

 

Source: OVPF

Piton de La Fournaise - Illustration of the deformation over 2 months, between April 2 and June 2, 2020. Here are represented the baselines (variation in distance between two GPS receivers) crossing the Piton de la Fournaise building, at top (top), at the base of the terminal cone (in the middle) and in the far field (bottom) (see location on the associated maps). An increase is synonymous with elongation and therefore swelling of the volcano; conversely, a decrease is synonymous with contraction and therefore deflation of the volcano. Any periods colored in light pink correspond to eruptions. - Doc. OVPF-IPGP

Piton de La Fournaise - Illustration of the deformation over 2 months, between April 2 and June 2, 2020. Here are represented the baselines (variation in distance between two GPS receivers) crossing the Piton de la Fournaise building, at top (top), at the base of the terminal cone (in the middle) and in the far field (bottom) (see location on the associated maps). An increase is synonymous with elongation and therefore swelling of the volcano; conversely, a decrease is synonymous with contraction and therefore deflation of the volcano. Any periods colored in light pink correspond to eruptions. - Doc. OVPF-IPGP

During the month of May at Yellowstone, the Steamboat geyser experienced no less than 5 watery eruptions, on May 8, 14, 19, 23 and 31. This brings the total number of eruptions for the year 2020 to 17.

In the very dynamic report by Mike Poland, volcanologist in charge (in English, but easily affordable thanks to subtitling), he also tells you about the overall style and rate of deformation in Yellowstone, which have remained unchanged since the last update.  Subsidence for the Yellowstone caldera, ongoing since 2015, continues at an average rate of 2 to 3 cm (about 1 inch) per year. In the Norris Geyser basin area, few deformations have been detected by a nearby GPS station since early 2020.

In May 2020, the University of Utah seismographic stations, responsible for operating and analyzing the Yellowstone seismic network, located 288 earthquakes in the Yellowstone National Park area. Such sequences of earthquakes are common; Yellowstone's seismic activity remains at the bottom level.

The volcanic alert level is Normal, and the aviation code green.

 

Source: Yellowstone volcano Observatory

Yellowstone Volcano Observatory Monthly Update: June 1, 2020 - by Mike Poland , volcanologist in charge.

Lire la suite

Publié le par Bernard Duyck
Publié dans : #volcanic activity
Suwanosejima - a permanent nocturnal glow is observed at the summit crater - photo 05.29.2020 TaTohru / Twitter)

Suwanosejima - a permanent nocturnal glow is observed at the summit crater - photo 05.29.2020 TaTohru / Twitter)

JMA reports that continuous eruptive activity has marked Suwanosejima, in the Ryukyu Islands, in recent days. The last eruptive episode dates from May 29 at 11:19 p.m. local, accompanied by a plume reaching 1,200 meters above sea level, drifting east.

Night glow marks the summit crater.

An area of ​​one kilometer radius around the crater is likely to be impacted by bombs and / or pyroclastic flows.

 

Source: Japan Meteorological Agency

Kusatsu-Shirane - Pyroclastic cones and crater lakes (Karagama, Yugama and Mizugama) overlap in the summit part of the massif - photo via Volcanologia Esia

Kusatsu-Shirane - Pyroclastic cones and crater lakes (Karagama, Yugama and Mizugama) overlap in the summit part of the massif - photo via Volcanologia Esia

The number of volcanic earthquakes increases again in Kusatsu-Shirane.

Authorities have closed some access roads following collapsed trees and landslides. Atmospheric conditions are unstable, with hail and thunderstorms in Nagano Prefecture.

 

Source: NBS Nagano

Karymsky - ash plume 29.05.2020 - Doc. PlatformAdam / Twitter

Karymsky - ash plume 29.05.2020 - Doc. PlatformAdam / Twitter

Karymski - the volcano, the caldera and the Karymsky lake - Doc. GVP

Karymski - the volcano, the caldera and the Karymsky lake - Doc. GVP

In Kamchatka, the activity of Karymsky, in orange aviation code, continues, with almost constant emissions of ash for weeks, with fallout of ash on the sides of the volcano and a dispersion towards a south-eastern sector.

On May 31, an ash plume was reported by KVERT, at 2,000 m amsl., as were thermal anomalies.

Klyuchevskoy - lava flow seen on 01.06.2020 by Sentinel-2 - Doc. Copernicus

Klyuchevskoy - lava flow seen on 01.06.2020 by Sentinel-2 - Doc. Copernicus

A Strombolian activity continues at Klyuchevskoy, with this May 31, an ash plume at 5,500 meters above sea level, and a lava flow in Apakhonchich chute, on the southeast flank of the volcano.

The aviation code remains orange.

 

Sources: KVERT, VAAC Tokyo and Sentinel-2

Þorbjarnarfell - photo Kristinn Magnusson 28.01.2020

Þorbjarnarfell - photo Kristinn Magnusson 28.01.2020

In Iceland, seismic activity has resumed on the Reykjanes peninsula since May 30. The IMO reports about 300 earthquakes since midnight, the strongest of M 2.7 felt in Grindavik.

During the week of May 20 to 27, 120 earthquakes were counted.

New GPS, InSAR, and radon measurements taken on May 26 indicate soft re-inflation near Þorbjörn; a longer-term series of measures is necessary to understand the processes and assess the risks. The phase of uncertainty declared by the Protecton Civile is still in force.

 

Source: IMO

Lire la suite

Publié le par Bernard Duyck
Publié dans : #volcanic activity
Pacaya - lava flow from MacKenney crater (people on the left give the scale) - photo William Chigne / Twitter 05.28.2020

Pacaya - lava flow from MacKenney crater (people on the left give the scale) - photo William Chigne / Twitter 05.28.2020

The insivumeh reports that, during the night and the morning of May 30, 2020, we were able to observe Strombolian explosions, with expulsion of incandescent materials at 50-100 meters above the MacKenney crater of Pacaya.

This activity feeds a large lava flow in a northeast direction, with a length of 700 meters.

 

Sources: Insivumeh and William Chigna

The insivumeh reports that, during the night and the morning of May 30, 2020, we were able to observe Strombolian explosions, with expulsion of incandescent materials at 50-100 meters above the MacKenney crater of Pacaya.  This activity feeds a large lava flow in a northeast direction, with a length of 700 meters.     Sources: Insivumeh and William Chigna

The insivumeh reports that, during the night and the morning of May 30, 2020, we were able to observe Strombolian explosions, with expulsion of incandescent materials at 50-100 meters above the MacKenney crater of Pacaya. This activity feeds a large lava flow in a northeast direction, with a length of 700 meters.   Sources: Insivumeh and William Chigna

At Kawah Ijen on Java, after the seismic rise from January 17, 2020 until May 29, 2020, a white gas with a thin to moderate gas intensity was observed about 50-300 meters from the summit or 250-500 m from the surface of the lake. Observations to crater lake did not show any change in the color of the crater water lake, the temperature of which fluctuated in the range of 24.5 to 40.3 ° C from January to mid-May 2020.

Kawah ijen - Sentinel-2 bands 12,11,4 image from 05.25.2020 - one click to enlarge

Kawah ijen - Sentinel-2 bands 12,11,4 image from 05.25.2020 - one click to enlarge

The PVMBG reports for May 29,

- a total of 49 blast earthquakes, with an amplitude of 3-45 mm, and a duration between 14 and 85 seconds.

- 9 shallow volcanic earthquakes, with an amplitude of 3-18 mm

- and 4 episodes of non-harmonic tremor, with an amplitude of 34 to 46 mm and a duration between 105 and 534 sec.

Under current conditions, the potential threat of volcanic activity from Mount Ijen is made up of high concentrations of volcanic gases around the crater which can suddenly increase, due to the rising bursts of gas bubbles from the bottom of the lake.

Kawah Ijen - 29.05.2020 - an atmosphere of drama - and the place of disappearance of the minor - Doc. PVMBG and Detik news / Istimewa
Kawah Ijen - 29.05.2020 - an atmosphere of drama - and the place of disappearance of the minor - Doc. PVMBG and Detik news / Istimewa

Kawah Ijen - 29.05.2020 - an atmosphere of drama - and the place of disappearance of the minor - Doc. PVMBG and Detik news / Istimewa

It is recommended to the communities around G. Ijen and to visitors / tourists / miners so as not to approach the edge of the crater or descend and approach the bottom of the crater at the top of G. Ijen, and do not spend the night in the area of ​​G. Ijen within a radius of 1 km from the crater. - However, the activity level remains at 1 / normal.

Recommendation to follow, because according to Detik news, a sulfur miner is missing. It is suspected that it fell into the acid lake.

According to witnesses, at 12:30 p.m. WIB on May 29, 2020, Andik and Alimik, along with other miners, heard the sound of a boom or explosion at the bottom of the crater lake of Mount Ijen. The boom caused the water to rise from the lake and formed a wave that encroached about 3 meters from the edge of the crater.

 

Sources: PVMBG & Detik news / Banyuwangi

White island - 30.05.2020 / 07h20 local - Geonet webcam

White island - 30.05.2020 / 07h20 local - Geonet webcam

White Island - 05.31.2020 / 9.30 a.m. NZST - webcam crater floor Geonet screenshot

White Island - 05.31.2020 / 9.30 a.m. NZST - webcam crater floor Geonet screenshot

Whakaari / White Island remains in a high state of volcanic unrest.

The gas flow varied above background levels and was high during our last observation flight. Most of the other monitoring parameters remain within the range observed in the past 2 months.

The volcanic alert level remains at level 2; The aviation color code remains yellow.

 

Source: GeoNet

Lire la suite

Publié le par Bernard Duyck
Publié dans : #volcanic activity
Fuego - plume and fine ash on the summit this 05.28.2020 - photo Conred

Fuego - plume and fine ash on the summit this 05.28.2020 - photo Conred

This May 28, 2020, moderate to strong Strombolian explosions are recorded in Fuego / Guatemala, at the rate of 8-12 per hour which raise columns of ash at 4,500-4,700 meters asl., dispersing south and southwest. Moderate avalanches are recorded in the Seca, Tanilyua, Ceniza, Trinidad and Las Lajas barrancas. Fine ashes fall on the volcano observatory.

The descent of Lahar is reported in the Barra Seca, a tributary of the Pantaleon river, located on the southwest flank of the volcano at 1 p.m.

A weak to moderate lahar is present in the Ceniza barranca tributary of the Achiguate river, from 4:20 p.m. Maintaining heavy rains can result in more lahars, carrying tree branches and volcanic material.

 

Sources: Insivumeh & Conred

Klyuchevskoy - 29.05.2020 / 07h21 Seen by F.Yu. Levinson-Lessing Kamchatkan Volcanological Station (Klyuchi village) - IVS FEB webcam RAS KVERT

Klyuchevskoy - 29.05.2020 / 07h21 Seen by F.Yu. Levinson-Lessing Kamchatkan Volcanological Station (Klyuchi village) - IVS FEB webcam RAS KVERT

Klyuchevskoy - Volcanic Ash Advisory for 29.05.2020 - Doc. VAAC Tokyo

Klyuchevskoy - Volcanic Ash Advisory for 29.05.2020 - Doc. VAAC Tokyo

In Kluychevskoy, an explosive-effusive activity is maintained, with ash explosions at 5,500-6,000 meters, drifting over 400 km towards the ESE.

A lava flow continues to descend the southeast flank, accompanied by phreatic bursts.

The aviation code remains orange.

 

Sources: KVERT & VAAC Tokyo

IBU - 28.05.2020 / 7:34 WIT - Photo Magma indonesia

IBU - 28.05.2020 / 7:34 WIT - Photo Magma indonesia

Ibu - seismicity at 05.28.2020 - Doc. Magma Indonesia - one click to enlarge

Ibu - seismicity at 05.28.2020 - Doc. Magma Indonesia - one click to enlarge

In the Moluccas, the Ibu volcano presents this May 28, 2020 a white-gray plume 200-800 meters from the summit.

The PVMBG provides information on the seismicity level:

- 76 eruption earthquakes, with an amplitude of 15-30 mm, and the duration of the earthquake 18-70 seconds.

- 87 collapse earthquakes, with an amplitude of 2 to 10 mm and an earthquake duration of 12 to 65 seconds. The sliding distance and the direction of fall are not observed.

- 189 blast earthquakes, with an amplitude of 5-14 mm, and an earthquake duration of 10-50 seconds.

- 18 episodes of harmonic tremor

- 9 tectonic earthquakes with an amplitude of 2 to 10 mm, S-P 11 to 32 seconds and an earthquake duration of 30 to 95 seconds.

 

Sources: PVMBG and Magma Indonesia

Whakaari / White Island - photo NZ Herald

Whakaari / White Island - photo NZ Herald

The results of the last gas measurement flight on Wednesday May 27 at Whakaari / White Island indicate an increase in gas flow since the previous flight on May 20. While previous observations indicated a tendency to return to levels typical of this volcano, the recent increase in the flow of SO2 and CO2 gases, main indicators of volcanic disturbances, could be attributed to a new batch of magma under the low-lying volcano. depth depth.

Thermal infrared images, taken during the observation flight on Wednesday May 20, show that the lava extrusions, detected for the first time in early January, are still very hot, around 500 ° C. The hot gases that are emitted around these lava lobes generate a "night glow" which can be seen on GeoNet night vision webcams.

Occasional episodes of slightly elevated tremors are observed, although overall tremor levels remain low and in the background levels for the volcano. This week, shallow-source volcanic earthquakes are recorded. Satellite deformation measurements show that the ground around the active ventilation zone has subsided by several centimeters since the eruption in December 2019.

 

These recent observations agree with a still very dynamic volcanic system, despite several monitoring parameters tending towards pre-eruption levels. A rash could occur with little precursor activity. The plausible triggers for an eruption remain the collapse of unstable materials around the vents, the sudden release of magma gas and the rapid entry of water onto the shallow magma body.

If an explosive activity produces an ash cloud, the likelihood of ash affecting the continent remains very low. Under appropriate weather conditions, the plume of gas and vapor can be seen on the continent in the form of weak acid rain.

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

 

Source: Geonet & NZ Herald

Lire la suite

Publié le par Bernard Duyck
Publié dans : #volcanic activity
Sakurajima - 26.05.2020 / 11.57 am - Doc. JMA

Sakurajima - 26.05.2020 / 11.57 am - Doc. JMA

 Sakurajima - volcanic ash advisory 27.05.2020 - Doc. VAAC Tokyo

Sakurajima - volcanic ash advisory 27.05.2020 - Doc. VAAC Tokyo

The explosive activity continues at Sakurajima, with some explosions and ash plumes covered with lightning.

We will pin an explosion at 11:57 am on May 26, with a vertical plume reaching 1,000 meters above the summit.

At the end of the day on May 26, around 9:07 p.m., an explosion at the summit crater of the Minamidake generated a plume of gas and ash rising up to 900 meters above the crater.

 

Another on May 27, reported by the VAAC Tokyo at 4:23 am, was accompanied by a plume at a flight altitude of 40, which could drift towards the ENE.

The JMA reports an explosion at 2 p.m., with a colored plume 2,000 meters above the crater.

 

Sources: JMA & VAAC Tokyo

Sakurajima Explosive eruption May 26, 2020 21:07 - 桜島 爆発的噴火

Activity continues at Karymsky, where KVERT reports an explosion on May 27, 2020, generating an ash plume at more than 6,000 meters asl., Drifting towards the ENE of the volcano.

The aviation code remains orange, as ash explosions are likely to occur at any time.

 

Sources: KVERT & VAAC Tokyo.

Karymsky - volcanic ash advisory 27.05.2020 - Doc. VAAC Tokyo

Karymsky - volcanic ash advisory 27.05.2020 - Doc. VAAC Tokyo

In Costa Rica, the eruptive activity of Rincon de La Vieja continues with regular hydrothermal explosions.

The Ovsicori reports for May 25, 2020, after a sequence of gas pulses, small, almost continuous eruptions - more than 10 episodes in an hour - accompanied by plumes 1,000 meters above the crater. Two episodes are pinned, at 5:35 p.m. local and 5:38 p.m. local, the latter with materials reaching the edge of the active crater.

On May 26, an eruption was recorded at 8:05 am local, without being able to specify the height of the plume for lack of visibility; it lasted a minute.

The same day, at 4:21 pm local time, another explosion generated a plume of 1,500 meters above the crater; the activity lasted 2 minutes.

 

Source: Ovsicori

Rincon de La Vieja - 25.05.2020 / 5:57 pm - photo Edward Valerio González via Ovsicori

Rincon de La Vieja - 25.05.2020 / 5:57 pm - photo Edward Valerio González via Ovsicori

In Merapi, on Java, on alert 2 / waspada, the PVMBG reports on the level of seismicity for this May 26, 202:

- 5 avalanche earthquakes, with an amplitude of 2 to 6 mm and an earthquake duration of 7 to 23 seconds. The sliding distance and the direction of fall are not observed.

- 4 blast earthquakes, with an amplitude of 2 to 9 mm and an earthquake duration of 8 to 22.9 seconds.

- 8 hybrid earthquakes, with an amplitude of 2-3 mm, S-P 0.3-0.4 seconds and an earthquake duration of 5-7.6 seconds.

 

Potential dangers currently present themselves in the form of pyroclastic flows linked to the possible partial collapse of the lava dome and the fall of volcanic material following explosive eruptions.

The area with a radius of 3 km from the summit of Mount Merapi is prohibited for human activities

 

Sources: PVMBG & BPPTKG.

Merapi - exhalation (gas blast) on 26.05.2020 / 06:22 - Doc. Volcano YT

Merapi - exhalation (gas blast) on 26.05.2020 / 06:22 - Doc. Volcano YT

Merapi - activity from 26.05.2020 / 00 at midnight - Doc. BPPTKG

Merapi - activity from 26.05.2020 / 00 at midnight - Doc. BPPTKG

Lire la suite

Publié le par Bernard Duyck
Publié dans : #volcanic activity

In Guatemala, the Pacaya presents a continuous strombolian activity, with ejection of incandescent materials to 25-50 meters above the summit crater Mackenney, emissions of gas and vapor plume, dispersed in the south and the southeast, and a lava flow on the northeast flank reaching the length of 300 meters on satellite images.

Seismicity is characterized by internal tremor associated with the rise of magma, degassing and Strombolian explosions.

 

Source: Insivumeh

Pacaya - image of the lava flow by Sentinel-2 bands 12,11,5 from 24.05.2020- Doc. Insivumeh

Pacaya - image of the lava flow by Sentinel-2 bands 12,11,5 from 24.05.2020- Doc. Insivumeh

Pacaya - image of the lava flow by Sentinel-2 from 24.05.2020- Doc. Insivumeh

Pacaya - image of the lava flow by Sentinel-2 from 24.05.2020- Doc. Insivumeh

At the Fuego, a lava flow a hundred meters long towards the Seca barranca is observed in the images of Sentinel-2, as well as avalanches of blocks reaching up to 280 meters in length.

The rains on the upper parts of the drainage generate weak to moderate lahars, marked by volcanic material, blocks of 1-2 meters in diameter, and trees. Insivumeh reports a lahar this May 25 at 8:15 p.m. local in Barranca Seca, and Rio Pantaleon.

 

Source: Insivumeh

Fuego - image of the lava flow by Sentinel-2 bands 12,11,5 of 24.05.2020- Doc. Insivumeh

Fuego - image of the lava flow by Sentinel-2 bands 12,11,5 of 24.05.2020- Doc. Insivumeh

The Geophysical Institute of Peru (IGP) reports that the eruptive activity of the Sabancaya volcano remains at moderate levels, with the continuous recording of explosions, on average 6 per day, accompanied by plumes of gas and ash up to 3 km high above the summit of the volcano.

During the period from May 18 to 24, the IGP recorded and analyzed the occurrence of approximately 525 earthquakes of volcanic origin, associated with the circulation of fluids (magma, gas, etc.) inside the volcano.

The monitoring of the deformation of the volcanic structure, using GNSS data (processed with fast orbits), does not present any significant anomalies.

Satellite surveillance identified the presence of 5 thermal anomalies with values ​​between 2MW to 15MW, associated with the presence of a body of lava on the surface of the crater of the volcano.

The volcanic alert level remains orange, with a recommendation not to approach within a 12 km radius of the crater.

 

Source: I.G. Peru

Sabancaya - activity summary between 18 and 24 May 2020 - Doc. I.G.Peru

Sabancaya - activity summary between 18 and 24 May 2020 - Doc. I.G.Peru

In Semeru, the PVMBG reports for the seismicity of May 26 between 0 and 12h local time :

- 32 eruption earthquakes, with an amplitude of 10-22 mm and lasting between 74 and 110 seconds.

- 2 avalanche earthquakes, with an amplitude of 3-5 mm and an earthquake duration of 47-63 seconds. The sliding distance and the direction of fall are not observed.

- 9 blast earthquakes, with an amplitude of 2 to 9 mm and an earthquake duration of 55 to 121 seconds.

 

On the satellite images, hot spots are always visible at the top and lower on the side at the level of the lava flow.

 

Sources: PVMBG and Sentinel-2

 Semeru - image of hot spots of 25.05.2020 by Sentinel2 bands 12,11,4 - One click to enlarge

 Semeru - image of hot spots of 25.05.2020 by Sentinel2 bands 12,11,4 - One click to enlarge

According to the volcanologist Yuri Demyanchuk, the dome of the Shiveluch which had collapsed following the eruption which occurred in August of last year and had formed a pyroclastic flow over fifteen kilometers, has conventionally reformed.

It is now visible to the naked eye from the Shiveluch station located about 50 km away.

According to the FEB RAS Institute of Volcanology and Seismology, the current Shiveluch eruption began on January 1, 2019. Since the beginning of the century, this is the ninth eruption of the volcano.

 

Sources: Kam24 & Volkstat, ru

Shiveluch - the dome visible to the naked eye (arrow) - photo Volkstat.ru / via Kam24

Shiveluch - the dome visible to the naked eye (arrow) - photo Volkstat.ru / via Kam24

Lire la suite

Publié le par Bernard Duyck
Publié dans : #volcanic activity
 Ebeko - 24.05.2020 / 08h04 - Doc. KB GS RAS / SVERT

Ebeko - 24.05.2020 / 08h04 - Doc. KB GS RAS / SVERT

The eruptive activity of the Ebeko continues in the northern Kurils.

This activity is characterized by explosions with more or less significant ash plumes, reaching 4,600 meters asl. May 24 at 2:15 a.m., according to KVERT. Several reports fell during the day reporting plumes at 3,600 meters at 4:36 am, 2,000 meters asl at 5:13 am, and on May 25, between 1,800 and 1,900 meters asl. The ashes drift east of the volcano.

The aviation color code remains orange.

 

Source: KVERT

Semeru - 24.05.2020 / 9:30 WIB - photo Suryana Arimbawa / Twitter

Semeru - 24.05.2020 / 9:30 WIB - photo Suryana Arimbawa / Twitter

On Java, the VAAC Darwin assigned the Semeru a red aviation code on May 24, 2020 at 11:01 p.m. Z, following ash observed 400 meters above the summit, and 4,000 meters (flight altitude 140).

An eruption, visually observed on May 24 at 9:30 am WIB, was accompanied by an ash plume at 3,876 meters asl.

At the seismicity level, the PVMBG signals:

- 50 eruption earthquakes, with an amplitude of 10-24 mm, and the duration of the earthquake 41-138 seconds.

- 7 blast earthquakes, with an amplitude of 2 to 9 mm and an earthquake duration of 45 to 100 seconds.

- 7 tectonic earthquakes with an amplitude of 8-40 mm, S-P 13-50 seconds and an earthquake duration of 40-109 seconds.

 

Sources: PVMBG, Magma Indonesia & VAAC Darwin.

Semeru - calm on 05.24.2020 / 12.10 p.m. WIB - Magma Indonesia webcam

Semeru - calm on 05.24.2020 / 12.10 p.m. WIB - Magma Indonesia webcam

For a few days, the activity of the crater of the Voragine of Etna had strongly decreased. This morning May 24, 2020, activity showed a slight increase for a few hours, and one of the explosions produced this magnificent ring of vapor, seen from the region of Monte Grosso, on the south side of the volcano.

Source: Boris Behncke

Etna - vapor ring emitted by La Voragine on 05.24.2020, seen from the southern flank of the volcano (on the left on the first photo and in zoom) - photos Boris Behncke
Etna - vapor ring emitted by La Voragine on 05.24.2020, seen from the southern flank of the volcano (on the left on the first photo and in zoom) - photos Boris Behncke

Etna - vapor ring emitted by La Voragine on 05.24.2020, seen from the southern flank of the volcano (on the left on the first photo and in zoom) - photos Boris Behncke

Lire la suite

Publié le par Bernard Duyck
Publié dans : #volcanic activity
 Etna by Zafferana Etnea - photo Boris Behncke 22.05.2020 / around 10am

 Etna by Zafferana Etnea - photo Boris Behncke 22.05.2020 / around 10am

The INGV Osservatorio Etneo, reports that from 02:12 UTC, strombolian activity increased in the saddle cone of the new crater of south-eastern of Etna. Explosive activity produces a cloud of volcanic ash reaching 4,500 m (above sea level) dispersed by the wind to the southwest. The VONA went red at 07:12 hours, before finding the Orange level at 13:16 hours.

Explosive activity also continues at the Voragine crater with periodic emissions of ash, which disperse rapidly near the summit area.

The magnitude of the volcanic tremor, compared to yesterday, has undergone a moderate increase, with large fluctuations around medium and high values. Currently, the amplitude values ​​are high and the source of the tremor continues to be located near the New SE crater. The infrasonic activity has shown a moderate increase and the sources are mainly located in the New SE crater.
The soil deformations do not show significant variations.

 

Source: INGVvulcani

Etna - 22.05.2020, respectively at 05.58 and 08.58 - LAVE webcam - one click to enlarge
Etna - 22.05.2020, respectively at 05.58 and 08.58 - LAVE webcam - one click to enlarge

Etna - 22.05.2020, respectively at 05.58 and 08.58 - LAVE webcam - one click to enlarge

Etna - amplitude of the tremor at 22.05.2020 / 08.10 am - Doc. INGV OE ECPN velocimeter

Etna - amplitude of the tremor at 22.05.2020 / 08.10 am - Doc. INGV OE ECPN velocimeter

An overview of Nishinoshima, in the Ogasawara Islands in southern Japan, was conducted by the Japan Coast Guards on May 18, 2020.

When approaching the island, the summit activity was coupled with degassing due to the arrival of lava at sea.

Nishinoshima - overview of 18.05.2020 / 13.52 - Doc. Japan Coast Guards

Nishinoshima - overview of 18.05.2020 / 13.52 - Doc. Japan Coast Guards

Strombolian explosions produce a plume of ash, and eject materials on the blanks of the pyroclastic cone. We can follow the progress of the lava towards the coast, thanks to the degassing of the flow.

On the thermal image, we can see that the lava flowing from the effusive vent on the southwest flank of the cone is divided into two arms, one of which forms a delta at the entrance to the sea.

Activity appears to be continuous, slightly up on April 29, 2020 overview

 

Source: Japan Coast Guards

Nishinoshima - overview of 18.05.2020 / 2:04 p.m. - Doc. Japan Coast Guards

Nishinoshima - overview of 18.05.2020 / 2:04 p.m. - Doc. Japan Coast Guards

Nishinoshima - overview of 18.05.2020 / 14h06 - thermal camera image - Doc. Japan Coast Guards

Nishinoshima - overview of 18.05.2020 / 14h06 - thermal camera image - Doc. Japan Coast Guards

In Costa Rica, the level of the laguna caliente du Poas rose following the rains and gave it a beautiful hue. The main mouths of the crater degas continuously.

The CO2 / SO2 and H2S / SO2 gas ratios remain in stable ranges. At the multigas station, the maximum concentration of SO2 reached 4.75 ppm, while at the watchtower, the maximum concentration reached more than 5 ppm on May 22 in the morning.

A tremor of 1 to 10 Hz is recorded.

Poas - 05.22.2020, respectively at 5:14 am and 6:38 am; and the Poas plume at 8:17 am, seen from the Irazu- webcam Ovsicori - one click to enlarge
Poas - 05.22.2020, respectively at 5:14 am and 6:38 am; and the Poas plume at 8:17 am, seen from the Irazu- webcam Ovsicori - one click to enlargePoas - 05.22.2020, respectively at 5:14 am and 6:38 am; and the Poas plume at 8:17 am, seen from the Irazu- webcam Ovsicori - one click to enlarge

Poas - 05.22.2020, respectively at 5:14 am and 6:38 am; and the Poas plume at 8:17 am, seen from the Irazu- webcam Ovsicori - one click to enlarge

An overview of the Rincon de La Vieja was also carried out on May 22, with the observation of a significant white of gas and vapor degassing in the active crater. A continuous tremor, between 0.6 and 5 Hz, is reported.

In addition, at 4:24 p.m. local time, a 1-minute eruption was accompanied by a plume that reached 1,000 meters above the crater. It followed a vapor emission.

 

Sources: Ovsicori & R.S.N.

Rincon de La Vieja - overview of 05.22.2020 - Ovsicori video screenshot

Rincon de La Vieja - overview of 05.22.2020 - Ovsicori video screenshot

Rincon de La Vieja - steam emission on 05.22.202 / 4:50 p.m. - Doc. Ovsicori

Rincon de La Vieja - steam emission on 05.22.202 / 4:50 p.m. - Doc. Ovsicori

An explosion occurred at the Nevados de Chillan Complex on May 22, 2020 at 11:36 am local time, associated with an LP seismic signal, in connection with the dynamics of internal fluids; the gas and ash plume rose to 2,200 meters above the emission bridge, before dispersing to the northeast.

The technical alert remains in Amarilla.

 

Source: Sernageomin

Lire la suite

Publié le par Bernard Duyck
Publié dans : #volcanic activity
 Dukono - plume of 21.05.2020 / 14:22 WIT - Doc. Magma Indonesia

Dukono - plume of 21.05.2020 / 14:22 WIT - Doc. Magma Indonesia

At Dukono, in the Molluques, the explosive activity continues, with this May 21, 2020 in plume reported by the VAAC Darwin at an altitude of 1,800 meters (flight alt. 060)

The PVMBG reports a thick white-gray plume 200-600 meters from the summit, and an episode of continuous tremor with an amplitude of 0.5 to 8mm, dominant at 2mm.

 

Sources: PVMBG, Magma Indonesia, VAAC Darwin

Merapi- the summit and the dome on May 20, 2020 / 07:46 - Doc. Volcano YT i Frekom

Merapi- the summit and the dome on May 20, 2020 / 07:46 - Doc. Volcano YT i Frekom

At Merapi, the week of May 15 to 21, 2020 was calm.

The BPPTKG reports a stable condition for the dome. The alert level remains at 2 / waspada; the seismicity remains low, with a superstructure on 20.05.

Potential dangers are currently in the form of pyroclastic flows in connection with the collapse of the lava dome, as well as possible explosive eruptions.

 

Source: BPPTKG

 Merapi - activity of 21.05.2020 / 00h-24 h. - Doc. BPPTKG

Merapi - activity of 21.05.2020 / 00h-24 h. - Doc. BPPTKG

In Costa Rica, the Ovsicori recorded a small ash eruption with Rincon de La Vieja, with less water vapor content than in the previous weeks, on May 21, 2020 at 5:37 am, accompanied by a plume to 1,000 meters above the crater. The activity lasted one minute.

Seismicity is characterized by semi-continuous tremor.

 

Source: Ovsicori

 Rincon de La Vieja - Ovsicori archives /  Fotografía por Federico Chavarría-Kopper

Rincon de La Vieja - Ovsicori archives / Fotografía por Federico Chavarría-Kopper

In Vanuatu, the Yasur volcano on level 2 volcanic alert / disturbances at a major level - with a danger zone of 600 meters around the cone, presents small emissions of gas and / or ash.

The VAAC Wellinton reports an ash emission on May 19, 2020, with a plume at 2,100 meters above sea level, drifting to the southeast.

The thermal anomalies vary between low (4-5 MW) and high (112 MW) between May 17 and 20, 2020.

 

Sources: Vanuatu Geohazards Observatory & VAAC Wellington

 Yasur - 05.22.2020 / 5:15 p.m. loc. - Doc. VGO

Yasur - 05.22.2020 / 5:15 p.m. loc. - Doc. VGO

Yasur - thermal anomalies and radiative power on 20.05.2020 / 11.45 am - Doc. Mirova
Yasur - thermal anomalies and radiative power on 20.05.2020 / 11.45 am - Doc. Mirova

Yasur - thermal anomalies and radiative power on 20.05.2020 / 11.45 am - Doc. Mirova

Lire la suite

Publié le par Bernard Duyck
Publié dans : #volcanic activity
Sakurajima - explosive activity of 20.05.2020 / 22.45 local time - phoyo DavidHe11952876 / twitter

Sakurajima - explosive activity of 20.05.2020 / 22.45 local time - phoyo DavidHe11952876 / twitter

The activity of the Sakurajima, currently on alert level 3 / climbing restrictions, has remained at a high level for a fortnight, with some nice explosions.

Among the most recent, the JMA noted a powerful explosion on May 20, 2020 at 10:45 pm local time, which generated a dense plume of ash and gas, reaching 4,000 meters and drifting east. Incandescent material was ejected on the slopes and caused block avalanches; the area affected by ballistic impacts and pyroclastic flows is set 2 km from the crater.

 

Sources: JMA & VAAC Tokyo

Sakurajima - 20.05.2020 / 22.54 - JMA webcam

Sakurajima - 20.05.2020 / 22.54 - JMA webcam

The KVERT signals a continuation of the eruptive activity of the Ebeko, in the northern Kurils.

On May 21, 2020, an explosion, observed by volcanologists based in Severo-Kurilsk, was accompanied by an ash plume at more than 2,600 meters asl., Drifting southeast over 5 km.

 

Source: KVERT

Ebeko - KVERT archives 28.04.2020 / photo Kotenko Leonid / IVS FEB RAS KVERT

Ebeko - KVERT archives 28.04.2020 / photo Kotenko Leonid / IVS FEB RAS KVERT

The lowered cone left by the eruption of Piton de La Fournaise between April 2 and 6, has just been baptized " Piton Voulvoul ", a Creole name of Malagasy origin, volvolo meaning small hairs ... like the many hairs of Pélé emitted by the lava fountains of the eruption, and scattered by the wind on a part of the island.

In the Plaine des Sables, these clusters took the form of rolls, like the sheep of dust on the floor of houses, the voulvoul in Creole. The Plaine des Sables and Les Hauts are whitened in this period by morning frosts ... the winter period will be cold on the volcano.

This name was assigned as always jointly by the Cité du volcan, the OVPF and the Réunion National Park.

 

Source: OVPF and Weather News 974

Piton de La Fournaise - Piton Voulvoul - photo OVPF 20.05.2020 / Twitter

Piton de La Fournaise - Piton Voulvoul - photo OVPF 20.05.2020 / Twitter

Piton Voulvoul owes its name to Pélé's hair, the wills in Creole - photo Patrice Huet / La cité du volcan

Piton Voulvoul owes its name to Pélé's hair, the wills in Creole - photo Patrice Huet / La cité du volcan

Piton de La Fournaise - The Plain of Sands under the Frost - photos Erine Pitou 19.05.2020 / Weather News 974 via OVPF

Piton de La Fournaise - The Plain of Sands under the Frost - photos Erine Pitou 19.05.2020 / Weather News 974 via OVPF

The pyroclastic materials emitted by the Tolbachik eruptions in 2012-2013 were analyzed: there were identified around 700 diamond crystals of cubo-octahedral shape, and homogeneous internal structures. Two groups of impurities could be determined: The first group, N and H, the most common structural impurities in diamonds, are distributed homogeneously. All the other elements observed (Cl, F, O, S, Si, Al, Ca and K) form local concentrations, implying the existence of inclusions, causing high concentrations of these elements.

Microdiamonds found in lava from the 2012-13 eruption at Tolbachik. “Mkm” scale is micrometer (0.00003 inch). (Credit Galimov et al. 2020 American Mineralogist)

Microdiamonds found in lava from the 2012-13 eruption at Tolbachik. “Mkm” scale is micrometer (0.00003 inch). (Credit Galimov et al. 2020 American Mineralogist)

The lavas of Tolbachik and the Goreli on 03/23/2013 - photo Lusika 33

The lavas of Tolbachik and the Goreli on 03/23/2013 - photo Lusika 33

Normally diamonds - xenocrysts - are part of foreign rock - xenolith - raised during a kimberlitic eruption; they are not really related to magma, but rather to its rise.

Tolbachik diamonds, according to geological, geochemical and mineralogical data, have their origin seeming linked to hot gases released after a massive explosive eruption ... hot volcanic gases loaded with carbon dioxide and other elements have cooled in bubbles and quickly crystallized the minerals into diamonds.

No rush to a new Eldorado ... these tiny diamonds simply show that they can form directly from a gas, without the need to have been subjected to strong pressures

 

Source: American Mineralogist - Enigmatic diamonds from the Tolbachik volcano, Kamchatka - link

Lire la suite

Archives

Articles récents

Hébergé par Overblog