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Earth of fire

Actualité volcanique, Articles de fond sur étude de volcan, tectonique, récits et photos de voyage

Articles avec #sismologia catégorie

Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
 Villarica - small explosion from 23.10.2020 / 10:41 local - photo Sernageomin

Villarica - small explosion from 23.10.2020 / 10:41 local - photo Sernageomin

An LP earthquake was recorded on October 23 at 10:41 am local time in Villarica, associated with a moderate explosion at the active crater, accompanied by a plume of ash 180 meters high in incline towards me .; the displacement reduced (DR) to 4.1 cm².

The technical alert remains at amarilla.

The POVI has established the schedule of pyroclast emissions over the last 2 months: in September 2020: 3 - in October 2020: 6.

Villarica - summary in photos (07.08.2020 / 20.10.2020) and schedule of pyroclast emissions over the last 2 months - Doc. POVI via Werner Keller
Villarica - summary in photos (07.08.2020 / 20.10.2020) and schedule of pyroclast emissions over the last 2 months - Doc. POVI via Werner Keller

Villarica - summary in photos (07.08.2020 / 20.10.2020) and schedule of pyroclast emissions over the last 2 months - Doc. POVI via Werner Keller

A drone flight over the Villarica crater by drone was carried out last week, revealing that recent explosions have deposited large lava splashes and boulders, some up to several meters. These projectiles are ejected, sometimes at supersonic speeds and reach parabolic trajectories. Its temperature is around 1000 ° C. Although the ascent is not forbidden, all those who undertake it must take into account these types of dangers, and the unpredictability of explosions, which lack instrumental precursors.

In addition, these explosions were caused by the conjunction between the level variations of the lava lake, which is a few hundred meters away in the conduit, and the falls of pyroclast crusts in the cylindrical conduit. 

 

Source: Sernageomin

Copahue - the plume seen from Caviahue 23.10.2020 - photo Valentina Sepulveda / Caviahue.

Copahue - the plume seen from Caviahue 23.10.2020 - photo Valentina Sepulveda / Caviahue.

In Copahue, on the Chilio-Argentina border, on October 23, we observe a plume of gas, lightly loaded with ash, blown by the winds above the village and Lake Caviahue.

According to Sernageomin, the seismic activity of the Copahue remains at a low level, but there are transient increases in the amplitude of the tremor, in relation to the emissions of particulate materials, suggesting the interaction between the magma and the superficial hydrothermal system. .

On the satellite images, we can observe a large area of ​​ash deposits estimated between 6-7 km. In diameter, mainly in the proximal area of ​​the crater.

 

Sources: Sernageomin and photo by Valentina Sepulveda / Twitter.

Etna - 23.10.2020 - activity of the "mouth of the Saddle" / NSEC - photo Gio Giusa

Etna - 23.10.2020 - activity of the "mouth of the Saddle" / NSEC - photo Gio Giusa

At Etna, an INGV press release dated 23.10.2020 / 8:32 UTC announces that the increase in explosive activity at the New Southeast Crater (NSEC), reported in the previous press release (Etna Communiqué 'Update n. 87 at 06:41 UTC), is no longer observable, as is the associated ash cloud.

However, strombolian activity of varying intensity remains at the NSEC, which fuels sporadic and light ash emissions that are rapidly dispersed in the summit area. Sporadic and light ash emissions can also be observed from the Bocca Nuova (BN) crater.

The temporal trend of the mean amplitude of the volcanic tremor and the location of its source, like infrasound activity, did not show significant changes. Signals from soil deformation monitoring stations do not show significant changes.

 

Source: INGV OE

Reykjanes Peninsula - location and magnitude of earthquakes as of 23.10.2020 / 2 p.m. - Doc. IMO
Reykjanes Peninsula - location and magnitude of earthquakes as of 23.10.2020 / 2 p.m. - Doc. IMO
Reykjanes Peninsula - location and magnitude of earthquakes as of 23.10.2020 / 2 p.m. - Doc. IMO

Reykjanes Peninsula - location and magnitude of earthquakes as of 23.10.2020 / 2 p.m. - Doc. IMO

IMO provided an update on October 23 on the seismic swarm of the Reykjanes Peninsula : On October 20 at 13:43, an earthquake of M5.6 occurred west of Kleifarvatn, at a depth of 10 km.

Almost 3,000 aftershocks were detected in the current swarm, the majority of them within two days of the M5.6 earthquake. About 30 aftershocks measured larger than M3.0. As of October 23, around 80 earthquakes were detected in the region, the largest of M2.6 near Kleifarvatn.

It is complicated to assess whether the swarm is decreasing or whether the activity has temporarily decreased. It is therefore not excluded that the seismic activity of the Reykjanes peninsula will increase again.

Reykjanes Peninsula - fisure in Krýsuvíkurbjarg on 10/21/2020, after the major earthquake of October 20 - photo Coast Guard Sævar Óskarsson / Visir.is

Reykjanes Peninsula - fisure in Krýsuvíkurbjarg on 10/21/2020, after the major earthquake of October 20 - photo Coast Guard Sævar Óskarsson / Visir.is

The meteorological office said on Wednesday there were indications that cracks in Krýsuvíkurbjarg had crept in and new ones were forming.

Ármann Höskuldsson, a geologist at the University of Iceland, says it is highly undesirable for people to travel on steep slopes or cliffs like in Krýsuvík during this earthquake cycle.

Reykjanes Peninsula - 10.2020 - The InSAR Sentinel-1 image of the co-seismic deformation shows the expected north-south right lateral setback failure (processed by Y. Cao, CDI Group, KAUST)

Reykjanes Peninsula - 10.2020 - The InSAR Sentinel-1 image of the co-seismic deformation shows the expected north-south right lateral setback failure (processed by Y. Cao, CDI Group, KAUST)

The InSAR Sentinel-1 image of the co-seismic deformation shows the expected north-south right lateral setback failure (processed by Y. Cao, CDI Group, KAUST). - via Sigurjón (Sjonni) Jónsson - Professor of Geophysics, KAUST

 

A full explanation of the seismic and intrusive phenomena that the Reykjanes Peninsula has experienced since early 2020 is given by Páll Einarsson, of the Institute of Earth Sciences, University of Iceland.

 

Sources: IMO, KAUST, Univ. Of Iceland

Earthquakes in the Reykjanes Peninsula - video in English (mixed with Icelandic accent, requiring focus) by Páll Einarsson / Univ of Iceland / Landhelgisgæsla Íslands

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
 Bezymianny - 21.10.2020 / 20h29 - Doc. KB GS RAS via Olga Girina

 Bezymianny - 21.10.2020 / 20h29 - Doc. KB GS RAS via Olga Girina

An explosive eruption of the Bezymyanny volcano occurred on October 21, 2020 at 20:22 UTC. The ash cloud is located above the Klyuchevskaya group of volcanoes. First reported at an altitude of 8,500 meters, the height of the ash cloud rose to 5,500 meters later.

The VAAC Tokyo has issued an ash dispersion advisory 4 times, as they cross various air routes during their dispersion.

A red aviation code was issued, before changing to orange.

Sources: VAAC Tokyo, KVERT & Olga Girina

Bezymianny - Thermal anomalies at 10/22/2020 / 02:25 am - Doc. Mirova MODIS
Bezymianny - Thermal anomalies at 10/22/2020 / 02:25 am - Doc. Mirova MODIS

Bezymianny - Thermal anomalies at 10/22/2020 / 02:25 am - Doc. Mirova MODIS

October 21, 2020, ~ Eruption ~ Bezymianny Volcano, Russia / Volcano Time lapse

Two other volcanoes are active in the Kamchatka Peninsula: Klyuchevskoy and Karymsky.

 

At Klyuchevskoy, the explosive-effusive eruption continues at a moderate level.

The almost continuous explosions produce plumes of gas and steam, containing a little ash, at an altitude of about 5,200 meters, drifting north-east.

The lava flow in Apakhonchich falls remains active.

The thermal anomalies noted by Mirova were of max. VRP 778 MW on October 20, 457MW on October 21, and Between VRP 652 and 425 MW on October 22, 2020.

Klyuchevskoy - Thermal anomalies at 22.10.2020 / 02:25 - Doc. Mirova Modis
Klyuchevskoy - Thermal anomalies at 22.10.2020 / 02:25 - Doc. Mirova Modis

Klyuchevskoy - Thermal anomalies at 22.10.2020 / 02:25 - Doc. Mirova Modis

At the Karymsky, according to data from pilots, explosions sent ash up to 4,000 m. altitude, around 02:30 UTC on October 21. The ash plume continues to drift south-east of the volcano for 40 km. The last Karymsky explosions were noted on July 29, 2020.

Moderate eruptive activity of the volcano continues. Ash explosions up to 19,700-23,000 feet (6-7 km) above sea level could occur at any time. Ongoing activities could affect low-flying planes.

The aviation code has changed to orange.

 

Sources: KVERT & VAAC Tokyo

Karymsky - photo A.Belousov via Volkstat / 21.10.2020

Karymsky - photo A.Belousov via Volkstat / 21.10.2020

Karymsky- volcanic ash advisory on 21.10.2020 / 0600Z  - Doc. VAAC Tokyo

Karymsky- volcanic ash advisory on 21.10.2020 / 0600Z - Doc. VAAC Tokyo

On October 20 at 13:43, an earthquake of M5.6 occurred in Núplahlíðarháls on the Reykjanes peninsula.

More than 2,000 aftershocks have been detected in the ongoing swarm. About 30 aftershocks measured more than M3.0 and some were felt in the Reykjanes Peninsula, the capital region and Borgarfjördur.

Travelers and hikers are advised to use caution near the steep slopes in Reykjanes due to the increased likelihood of rockfall as the seismic swarm continues.

Source: IMO

Reykjanes peninsula - seismic swarm at 10/22/2020 / 07:15 am - Doc. IMO
Reykjanes peninsula - seismic swarm at 10/22/2020 / 07:15 am - Doc. IMO

Reykjanes peninsula - seismic swarm at 10/22/2020 / 07:15 am - Doc. IMO

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
 Karymsky - photo D. Melnikov. IVS FEB RAS, KVERT 13.10.2020

 Karymsky - photo D. Melnikov. IVS FEB RAS, KVERT 13.10.2020

Karymsky - Volcanic ash advisory - Doc Vaac Tokyo 21.10.2020 - 0600Z

Karymsky - Volcanic ash advisory - Doc Vaac Tokyo 21.10.2020 - 0600Z

According to data from AMC Elizovo (pilots), explosions from the Karymsky sent ash up to 4,000 m. altitude, around 02:30 UTC on October 21. The ash plume continues to drift south-east of the volcano for 40 km. The last Karymsky explosions were noted on July 29, 2020.

Moderate eruptive activity of the volcano continues. Ash explosions up to 19,700-23,000 feet (6-7 km) above sea level could occur at any time. Ongoing activities could affect low-flying planes.

The aviation code has changed to orange.

 

Sources: KVERT & VAAC Tokyo

 Merapi - photo BPPTKG 10/21/2020 / 6:29 a.m.

Merapi - photo BPPTKG 10/21/2020 / 6:29 a.m.

Merapi - summary of the seismic activity of 20.10.2020 / 00-24h WIB - Doc. BPPTKG

Merapi - summary of the seismic activity of 20.10.2020 / 00-24h WIB - Doc. BPPTKG

Thanks to the seismographic recordings of October 20, 2020, it was recorded at Merapi, where the activity seems more intense:

- 28 earthquake collapse

- 37 blast earthquakes

- 27 low frequency earthquake

- 83 hybrid / multiphase earthquakes

- 18 shallow volcanic earthquakes

- 2 distant tectonic earthquakes.

The current potential danger is in the form of pyeoclastic flows associated with the collapse of the lava dome and the fall of volcanic material due to explosive eruptions.

Activity level remains at 2 / waspada, with a 3 km no-go zone from the summit.

 

Sources: PVMBG & BPPTKG

Villarica - photo Sernageomin 20.10.2020 17:22 loc.

Villarica - photo Sernageomin 20.10.2020 17:22 loc.

On October 20 at 5:22 p.m. local time, an LP earthquake occurred in Villarica, associated with a moderate explosion at the active crater, accompanied by an ash plume reaching 240 meters above the emission bridge.

No significant changes in seismicity, the volcanic technical alert remains at amarilla.

 

Source: Sernageomin

 Reykjanes Peninsula - earthquakes at 20.10.2020 / 15:40 - Doc .IMO

Reykjanes Peninsula - earthquakes at 20.10.2020 / 15:40 - Doc .IMO

Reykjanes Peninsula - earthquakes at 21.10.2020 / 06:30 - Doc .IMO
Reykjanes Peninsula - earthquakes at 21.10.2020 / 06:30 - Doc .IMO
Reykjanes Peninsula - earthquakes at 21.10.2020 / 06:30 - Doc .IMO

Reykjanes Peninsula - earthquakes at 21.10.2020 / 06:30 - Doc .IMO

At 1:43 p.m. on October 20, an M5.6 earthquake occurred in Núpshlíðarháls, about 5 km west of the Seltún geothermal area on the Reykjanes peninsula.

The earthquake was felt widely across the country, particularly in the southern part of the Reykjanes peninsula and in the capital region, about 25 km from the epicenter.The earthquake was felt also in the Westman Islands and Borgarnes.

To date, more than 250 aftershocks have been detected, the most important of the period between 3:27 pm and 3:32 pm The most important was M4.1, the other earthquakes between 3.0 and 3.8 . There is no sign of volcanic unrest in the area.

Krýsuvík - small slow landslide on 20.10.2020 - photo Arni Saeberg / mbl.is

Krýsuvík - small slow landslide on 20.10.2020 - photo Arni Saeberg / mbl.is

Today's earthquake is the largest measured earthquake in the Reykjanes Peninsula since 2003.

"There is a long term active process underway in the region and we can expect that there will be more earthquakes in the coming hours that will make themselves felt all the way to the capital region. ", says Kristín Jónsdóttir, seismic risk coordinator at the Islandic Met Office, in an interview with RÚV today.

GPS measurements indicate that a slow landslide is taking place near Krýsuvík, according to Kristín Jónsdóttir. When asked about the next steps, she says an announcement has been received of an unusually strong smell of gas and Kristín believes that today's large earthquake "only took root in the geothermal system."

 

Sources: IMO, RUV, EMSC

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
Etna - activity of the new south-eastern crater on 08/29/2020 - photo Gio Giusa

Etna - activity of the new south-eastern crater on 08/29/2020 - photo Gio Giusa

The National Institute of Geophysics and Volcanology, Etneo Observatory, announces that the activity of the new SE crater of Etna is characterized, from the morning of August 28, by a discontinuous and modest ash emission which produces a strongly volcanic cloud. diluted, light gray in color.

The volcanic cloud, which reaches a height of about 4.5 km above sea level, is quickly dispersed eastward by high-altitude winds.

Concerning the temporal trend of the mean amplitude of the volcanic tremor: it continues to show marked amplitude fluctuations with respect to the whole, defining a substantially stationary trend which is mainly maintained in the range of mean values. The location of the source of the quake is located near the SE crater / new south-eastern crater, at a depth of about 2900-3000 meters above mean sea level.

From an infrasonic activity perspective, over the past 24 hours, events have mainly resulted from areas at the New Southeast Crater and the Northeast Crater.

Analysis of the data from the permanent and clinometric GNSS networks shows no significant soil deformation.

 

From 11:30 UTC, the ash emission gradually intensified at New SE Crater, which produced an eruptive cloud that reached a height of about 4.5 km above sea level towards the EAST / BORN.

There are currently no reports of ash fall in the inhabited centers of the Etnean region.

Concerning the temporal trend of the mean amplitude of the volcanic tremor, it continues to show marked amplitude fluctuations compared to the whole.
 

Etna - ash plume from the new south-eastern crater on 08/29/2020 - photo Gio Giusa

Etna - ash plume from the new south-eastern crater on 08/29/2020 - photo Gio Giusa

Etna - amplitude of the tremor on 08/30/2020 - Doc INGV OE

Etna - amplitude of the tremor on 08/30/2020 - Doc INGV OE

The National Institute of Geophysics and Volcanology, Etneo Observatory, informs that around 14:55 UTC on August 29, the emission of ash at the new south-eastern crater has ceased.

There remains an intense degassing, sometimes accompanied by a discontinuous and light explosive activity.

 

Sources: INGV OE & Gio Giusa

Reykjanes Peninsula - location and magnitude of earthquakes as of 08/30/2020 / 6:55 am - Doc. IMO
Reykjanes Peninsula - location and magnitude of earthquakes as of 08/30/2020 / 6:55 am - Doc. IMO
Reykjanes Peninsula - location and magnitude of earthquakes as of 08/30/2020 / 6:55 am - Doc. IMO

Reykjanes Peninsula - location and magnitude of earthquakes as of 08/30/2020 / 6:55 am - Doc. IMO

At 7:06 p.m. and 7:08 p.m. on August 29, earthquakes M3.6 and M3.0 occurred just west of Kleifarvatn on the Reykjanes peninsula. Two earthquakes of similar magnitude, M3.4 and M3.0 occurred in the same location at 4:23 pm and 4:39 pm yesterday. The earthquakes were felt in the Reykjanes Peninsula, the capital region and Akranes. Smaller aftershocks have since occurred and are expected to continue.

The seismic activity is likely caused by stress changes in the crust due to multiple magma intrusions on the Reykjanes Peninsula since January this year.

 

Source: IMO

Yellowstone N.P. - Giantess Geyser - photo J.R. Douglass / NPS archives

Yellowstone N.P. - Giantess Geyser - photo J.R. Douglass / NPS archives

In Yellowstone, the Giantess Geyser, located in the Upper Geyser Basin, came into operation on August 25, after an eruption-free period of over 6.5 years.

See the video on: https://twitter.com/i/status/1299708384015458307

 

Source: Yellowstone NPS

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia

In Fuego, Guatemala, the explosions follow one another at a rate of 4 to 6 per hour, accompanied by shock waves, avalanches of blocks in the direction of the Seca, Taniluya, Ceniza, Trinidad and Las Lajas drainages, some of which reach the limit of vegetation, and ash plumes at 4,500-4,700 meters above sea level.

Ash falls are reported in the villages of Panimaché I, Morelia, Finca Palo Verde and Yepocapa.

Incandescent pulses are observed during the night and early in the morning.

 

Source: Insivumeh

Fuego - explosion of 08/26/2020 / 2h31 - Doc. IDIS / Epcom / CRELOSA

VAAC Darwin reports discreet eruptive activity over Kadovar, Papua New Guinea; the ash can reach flight altitude 70, while the plume of sulfur dioxide moves far to the northwest.

 

Sources: VAAC Darwin and Sentinel-2

Kadovar - image Sentinel-2 L1C bands 12,11,4 from 08/22/2020 - one click to enlarge

Kadovar - image Sentinel-2 L1C bands 12,11,4 from 08/22/2020 - one click to enlarge

On August 26, 2020 at 4:15 PM, an M4.2 earthquake occurred about 10 km NE of Grindavík. Another M3.7 earthquake occurred in a similar location at 1:43 p.m. IMO has received many felt reports from the southwestern part of Iceland regarding these earthquakes.

At 5:06 am on August 27, an M2.9 earthquake was detected near Fagradalsfjall but a swarm of earthquakes is still in progress there.

In total, the IMO reports five earthquakes of magnitude equal to or greater than 3 over the last two days.

 

An intense seismic swarm began on July 19 in the Reykjanes Peninsula. More than 5,000 earthquakes have been detected since then. This seismic activity is likely caused by a stress change in the crust due to multiple magma intrusions on the Reykjanes Peninsula since January of this year.

 

Source: IMO

Reykjanes Peninsula - location and magnitude of earthquakes as of 08/27/2020 / 6:40 a.m. - Doc. IMO
Reykjanes Peninsula - location and magnitude of earthquakes as of 08/27/2020 / 6:40 a.m. - Doc. IMO
Reykjanes Peninsula - location and magnitude of earthquakes as of 08/27/2020 / 6:40 a.m. - Doc. IMO

Reykjanes Peninsula - location and magnitude of earthquakes as of 08/27/2020 / 6:40 a.m. - Doc. IMO

The fissured slope of the Irazú volcano, located on the western flank of the Carthaginian colossus, collapsed on the morning of August 26 at a rate that remains to be determined.

The event took place at around 4:10 a.m. when officials who were there began to perceive a seismic movement and vibration which, according to their reports, lasted for about a minute and a half.

Cyril Muller, an Ovsicori expert, told Costa Rica Noticias that just yesterday there were at least 100 small landslides; and that between Monday and Tuesday, the crack in the slope had moved 40 centimeters.

The displaced materials are estimated to be several million cubic meters of earth.

Alexander Solís, president of the National Emergency Commission (CNE) said in Repretel News that this event is a landslide and has nothing to do with volcanic activity.

The damage is material, and concerns telecommunications installations that could not be moved.

 

Sources : Ovsicori Videos and Media from Costa Rica

https://www.facebook.com/OVSICORI/videos/1410561832465897

https://www.facebook.com/OVSICORI/videos/868543520339934

Irazu - the area affected by the landslide, and movement between February and August towards the NW - Doc. Ovsicori

Irazu - the area affected by the landslide, and movement between February and August towards the NW - Doc. Ovsicori

Irazu - seismic traces of the landslide of 26.08.2020 - Doc.Ovsicori

Irazu - seismic traces of the landslide of 26.08.2020 - Doc.Ovsicori

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
Suwanosejima - 17.08.2020 - image Sentinel-2 / EO browser / Copernicus

Suwanosejima - 17.08.2020 - image Sentinel-2 / EO browser / Copernicus

A small explosion occurred on August 17 in Suwanosejima, in the Ryulyu volcanic arc. According to reports, ash emissions reached up to 2,133 m above sea level.

An eruption was reported by the JMA on August 18, 2020 around 8 p.m. at Suwanosejima; it was accompanied by a plume of gas and ash which rose to 1,200 meters above the crater, then dissipated towards the south

Source: JMA & Copernicus / Sentinel-2

Suwanosejima - eruptive plume on 08/18/2020 / 8 p.m. - JMA webcams

Suwanosejima - eruptive plume on 08/18/2020 / 8 p.m. - JMA webcams

The main plume of the crater, white and gray, with a moderate to thick intensity, is observed this August 18 at about 2000 meters from the summit of Sinabung.

At the level of seismicity, we distinguish :

- 6 blast earthquakes, with an amplitude of 12 to 45 mm and a duration of 22 to 73 seconds.

- 32 low frequency earthquakes, with an amplitude of 2 to 15 mm, and the duration of the earthquake was 7 to 16 seconds.

- 4 local tectonic earthquakes, with an amplitude of 4-34 mm, S-P 1.6-3 seconds and a long earthquake of 11-29 seconds.

- 3 distant tectonic earthquakes, with an amplitude of 5-13 mm, S-P 28.4-31 seconds and a long earthquake of 86-696 seconds.

- 4 episodes of continuous tremor with an amplitude of 0.5 to 60 mm, dominating 10 mm.

 

The activity level is at 3 / siaga, with a red aviation code.

 

Sources: PVMBG, Magma Indonesia and VAAC Darwin.

Sinabung - 18.08.2020 - ash plume 2,000 meters above the summit - photo Sadrah Peranginangin

Sinabung - 18.08.2020 - ash plume 2,000 meters above the summit - photo Sadrah Peranginangin

Sinabung - time-lapse 18.08.2020 - Doc. PVMBG via Volcano YT

Two violent earthquakes off Bengkulu rocked the Indonesian island of Sumatra. The 6.8 and 6.9 magnitude earthquakes occurred at 5:23 a.m. local / 10:23 p.m. GMT and 5:29 a.m. local / 10:29 p.m. GMT on August 18, 2020, as reported by monitoring stations.

No tsunami warning has been issued, nor an assessment of the damage caused by these earthquakes.

They have to do with the subduction of the Indo-Australian plate under the Sunda plate.

 Strong earthquakes off Bengkulu / Sumatra - 08/18/2020 - Doc. Temblor

Strong earthquakes off Bengkulu / Sumatra - 08/18/2020 - Doc. Temblor

The Manna seismic station, south of Bengkulu, recorded 2 earthquakes of M greater than 6 on 08/18/2020.

The Manna seismic station, south of Bengkulu, recorded 2 earthquakes of M greater than 6 on 08/18/2020.

An earthquake of M 6.6 struck Masbate Island on August 18, 2020 at 8:30 a.m. local / 12:03 a.m. GMT in the Philippines. It was followed by strong aftershocks.

We deplore one death and dozens of wounded; much damage to homes is due to its shallow depth and power.

The origin is tectonic.

 

Sources: USGS Earthquake Hazards - EMSC - Local Observatory

 Philippines / Masbate region - damage to homes on 08/18/2020 - photo Philippine Red Cross Masbate

Philippines / Masbate region - damage to homes on 08/18/2020 - photo Philippine Red Cross Masbate

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
Sinabung - eruptive episode and pyroclastic flows of 08/10/2020 / 10:16 a.m. - photo PVMBG & Magma Indonesia

Sinabung - eruptive episode and pyroclastic flows of 08/10/2020 / 10:16 a.m. - photo PVMBG & Magma Indonesia

The activity of Gunung Sinabung seems to have regained its past eruptive mode, with this August 10, 2020 at 10:16 WIB a plume of ash and gas with a height of ± 5000 m above the summit (± 7460 m above the level from the sea).

A new eruptive episode occurred at 11:17 local time.

 

In terms of seismicity, we notice an increase in the number of deep volcanic earthquakes:

- on August 9, 39 deep volcanic earthquakes, with an amplitude of 2 to 70 mm, S-P 1.1 to 4 seconds and an earthquake duration of 9 to 23 seconds.

- This August 10, between 00h and 12h, 47 deep volcanic earthquakes - with an amplitude of 2 to 30 mm, SP 1.5 to 4 seconds and duration of the earthquakes from 9 to 21 seconds between 00 and 6 a.m., then with an amplitude of 2-120 mm, SP 1.4-4 seconds and the duration of the earthquakes of 9-23 seconds, between 6 and 12h.

Between 6 a.m. and 12 p.m., there are 2 eruption earthquakes, with an amplitude of 120 mm, and a duration of 1785-2246 seconds.

 

Currently, Mount Sinabung is at level III / Siaga

 

Source: Dr. Devy Kamil Syahbana and Magma Indonesia

 Sinabung - episode of 08/10/2020 / 11:32 WIB - photo PVMBG & Magma Indonesia

Sinabung - episode of 08/10/2020 / 11:32 WIB - photo PVMBG & Magma Indonesia

Sinabung - seismicity as of 09.08.2020 - increase in deep volcanic earthquakes - Doc. Magma Indonesia

Sinabung - seismicity as of 09.08.2020 - increase in deep volcanic earthquakes - Doc. Magma Indonesia

Etna presented at the NSEC's "saddle cone" an increased Strombolian activity on the night of August 9, followed by ash emissions with an impressive plume seen from Torre del Filosofo at 3,000 meters.

 

Sources: Boris Behncke, Salvatore lo Giudice and Gio Giusa

 Etna - Strombolian activity at the SEC saddle cone, reflected on the clouds on 07.08.2020 - photo Boris Behncke

Etna - Strombolian activity at the SEC saddle cone, reflected on the clouds on 07.08.2020 - photo Boris Behncke

Etna - ash emission on 09.08.2020, view from Torre del Filosofo - photo Gio Giusa

Etna - ash emission on 09.08.2020, view from Torre del Filosofo - photo Gio Giusa

Regarding the monitoring of the activity of the Nevado del Ruiz volcano, the Servicio Geologico Columbiano, informs that from August 8, 2020 at 00:50 (local time), there was a significant increase in the volcano- seismic activity. tectonic, associated with the fracturing of rocks around the volcanic building.

The seismic activity is located in the West-South-West sector at an average distance of 6.0 km from the Arenas crater. The recording of a volcano-tectonic earthquake that occurred at 7:04 a.m. (local time), at a depth of 4.1 km with a magnitude of 3.1 ML (local magnitude), is reported as felt by officials of the National Natural Park of Los Nevados.

The Nevado del Ruiz volcano continues at activity level 3 amarilla / changes in the behavior of volcanic activity.

 

Source: SGC

Nevado del Ruiz - photo SGC

Nevado del Ruiz - photo SGC

In Iceland, the seismic swarm in the Eyjafjördur / Tjörnes FZ area seems to be resuming on August 9, with 3 earthquakes of magnitude between 3.5 and 4.5. earthquakes of magnitude 3 or less have continued since.

 

Source: IMO

Iceland - seismic swarm of Tjörnes FZ at 08.09.2020 / 4:35 p.m. - location and magnitude of earthquakes - Doc. IMO
Iceland - seismic swarm of Tjörnes FZ at 08.09.2020 / 4:35 p.m. - location and magnitude of earthquakes - Doc. IMO
Iceland - seismic swarm of Tjörnes FZ at 08.09.2020 / 4:35 p.m. - location and magnitude of earthquakes - Doc. IMO

Iceland - seismic swarm of Tjörnes FZ at 08.09.2020 / 4:35 p.m. - location and magnitude of earthquakes - Doc. IMO

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
Activity of Sabancaya, Ubinas and earthquake south of Big Island

The Geophysical Institute of Peru (IGP) reports that the eruptive activity of the Sabancaya volcano remained between July 20 and July 26 at moderate levels, with the continuous recording of explosions, on average 13 per day, with plumes of gas and ash up to 2.6 km above the top of the volcano.

The IGP recorded and analyzed the occurrence of about 400 earthquakes of volcanic origin, associated with the circulation of magmatic fluids (magma, gas, etc.) inside the volcano.

The monitoring of the deformation of the volcanic structure, using GNSS data (processed with fast orbits), did not show any significant anomalies; however, a slight inflation was recorded in the northern sector (Hualca Hualca volcano) and south-eastern flank of the Sabancaya volcano. Satellite monitoring has identified the presence of 5 thermal anomalies with values ​​between 1 MW and 4 MW VRP, associated with the presence of a lava body on the surface of the volcano crater.

The volcanic alert level remains orange, with a prohibited area of ​​12 km in radius around the crater.

 

Source: IG Peru

Activity of Sabancaya, Ubinas and earthquake south of Big Island

The Ubinas volcano (Moquegua region) continues to show a slight increase in its seismic activity between July 20 and July 26; twenty earthquakes of magnitudes less than M1.5, associated with rock breaking processes that occur inside the volcano have been recorded; similarly, 6 seismic signals were recorded which would be associated with the movements of volcanic fluids (water vapor and gas); Within these, 2 tornillo-type events were identified which would be linked to the increase in the internal pressure of the volcano. No seismic activity linked to the rise of magma is observed.

Surveillance cameras recorded columns of gas and water vapor reaching heights of up to 700 m above the summit of the volcano, dispersed towards the southeastern sector of the volcano.

The monitoring of the deformation of the volcanic structure, using GNSS instruments, as well as the satellite monitoring via the SENTINEL, IMO-NASA (SO2 gas) and MIROVA (thermal anomalies) systems did not record any anomalies. during the analysis period.

The volcanic alert level remains at Naranja, with a forbidden zone of 3 km in radius around the crater

 

Source: IG Peru

Activity of Sabancaya, Ubinas and earthquake south of Big Island

The US Geological Survey's Hawaiian Volcanoes Observatory (HVO) recorded a magnitude 4.7 earthquake between Lōʻihi seamont and the southern tip of the island of Hawaii on Monday, July 27 at 6:06 a.m. HST .

The earthquake was centered about 20 km (12.4 miles) southeast of Nā’ālehu, at a depth of 35 km (21.7 miles). Slight shaking, with a maximum intensity of IV, has been reported in parts of the island of Hawaii. At this intensity, significant damage to buildings or structures is not expected.

Acting HVO scientist David Phillips said the earthquake had no apparent effect on Kīlauea or Mauna Loa volcanoes. "We are not seeing any detectable change in activity at the summits or along the Mauna Loa or Kīlauea rift zones as a result of this earthquake. Aftershocks are possible and could be felt." The HVO continues to monitor Mauna Loa and other Hawaiian volcanoes for any changes.

The depth, location and recorded seismic waves of the earthquake suggest a source due to the bending of the oceanic plate under the weight of the Hawaiian island chain, a common source of earthquakes in this region. Aftershocks are possible and could be felt.

According to the Pacific Tsunami Warning Center, this earthquake does not threaten a tsunami.

 

Source: HVO

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Publié le par Bernard Duyck
Publié dans : #Sismologia
 Fagradalsfjall - photo Ferlir

 Fagradalsfjall - photo Ferlir

Reykjanes Peninsula - location and magnitude of earthquakes on July 20, 2020 / 06:40 a.m. - IMO doc
Reykjanes Peninsula - location and magnitude of earthquakes on July 20, 2020 / 06:40 a.m. - IMO doc

Reykjanes Peninsula - location and magnitude of earthquakes on July 20, 2020 / 06:40 a.m. - IMO doc

In the Reykjanes Peninsula, an earthquake between M5 occurred at 23:36 in the area of ​​Fagradalsfjall, a tuya formed during the Pleistocene. The earthquake was widely felt in the southwestern part of Iceland.

A considerable number of aftershocks occurred, the most significant were M3.5 at 00:08, M3.4 at 00:55, M3.0 at 02:19 and M3.4 at 03:09 and these were also felt in the southwest of Iceland. .

At 5:46 am, an M4.6 was detected. Rockfall was reported at Festarfjall, about 6 km SW of the epicenter of the earthquake.

On July 18 at 05:56 a.m., an M4.1 earthquake was detected 4.1 km north of Grindavík.

 

Earthquakes around Grindavík have continued in recent months due to deformation in the area.

 

Source: IMO

Location of the Fagradalsfjall tuya in the Reykjanes Peninsula

Location of the Fagradalsfjall tuya in the Reykjanes Peninsula

Fagradalsfjall - Lava flow dating from the Pleistocene - photo Banco imagenes geologicas / Flickr

Fagradalsfjall - Lava flow dating from the Pleistocene - photo Banco imagenes geologicas / Flickr

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia

Sernageomin raised the technical alert level of Copahue in Amarilla on July 17 at 3.30 p.m. local time.

During the previous months, the seismicity was marked by numerous VLP earthquakes, in relation with the rise of magma to more superficial levels; in addition, in recent days, signs have been observed on the surface, with the emission of particulate materials associated with a column of gas from the active crater, and incandescence. The satellite images indicate a decrease in the volume of the crater lake ... all these signs testify to my presence of a volume of magma at a superficial level.

An area of ​​1,000 meters in radius around the crater is considered as a possible assignment area.

 

Source: Sernageomn OVDAS

Copahue - 16.07.2020 - ash plume - Mayores Sin Limites video / twitter

Copahue - 16.07.2020 - ash plume - Mayores Sin Limites video / twitter

Copahue - 07.16.2020 - video noticias NQN

The Raung alert level on the island of Java was raised to 2 / waspada on July 17.

Today, between 0 and 6 a.m., a total of 26 brown plumes were observed between 50 and 200 meters above the crater.

The seismicity of July 17 is characterized by :

- 98 eruption earthquakes with an amplitude of 2-17 mm and a duration of 40-155 seconds.

- 83 non-harmonic tremor episodes with an amplitude of 1-5 mm, and a duration of 38-399 sec.

The PVMBG recalls the ban on going down into the crater, and camping within a radius of 2 km in the center of the crater, due to the danger of volcanic gases for life.

 

Sources: PVMBG & Magma Indonesia

 Raung - seismicity at 17.07.2020 - Doc. Magma Indonesia

Raung - seismicity at 17.07.2020 - Doc. Magma Indonesia

In Costa Rica, a passive emission occurred at Turrialba on July 16, 2020 at 12:09 p.m., accompanied by an ash plume 200 meters above the crater; it lasted 2 minutes.

This episode was followed by several other very diluted shows during the day.

A peak in the CO2 / SO2 and H2S / SO2 ratios was recorded overnight, before returning to values ​​similar to those of yesterday.

 

Source: Ovsicori

Turrialba - 07/16/2020 / 12:09 - Ovsicori webcam

Turrialba - 07/16/2020 / 12:09 - Ovsicori webcam

A magnitude 4.1 earthquake occurred 4.1 km from Grindavik, on the Reykjanes Peninsula in Iceland.

It was preceded by another of magnitude 3; 2. Both were felt in Grindavik and Reykjanesbaer.

The persistent seismic activity is, according to the IMO, in relation to the deformation due to magmatic intrusions in the earth's crust.

 

Sources: IMO & mbl, is

Reykjanes peninsula - 07/18/2020 - earthquake magnitude at 07:50 - Doc. IMO

Reykjanes peninsula - 07/18/2020 - earthquake magnitude at 07:50 - Doc. IMO

Grindavík with Mount Þorbjörn in the background. - Doc. mbl.is / Kristinn Magnússon

Grindavík with Mount Þorbjörn in the background. - Doc. mbl.is / Kristinn Magnússon

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