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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 : #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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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
Nevados de Chillan - 13.07.2020 in the late evening - glow of the lava flow - photo Josefauna / Volcanologia in Chile

Nevados de Chillan - 13.07.2020 in the late evening - glow of the lava flow - photo Josefauna / Volcanologia in Chile

In Nevados de Chillan, the viscous lava flow emanating from the Nicanor crater continues to descend slowly the northern flank of the volcano.

The Sernageomin has determined a danger zone of 3 km to the west and up to 5 km to the east.

At night, we can notice the glow emitted by the flow; its emission rate is around 0.2m³ / sec.

 

Source: Sernageomin and Volcanologia in Chile

Nevados de Chillan - the lava flow during the day on 14.07.2020 - webcam Sernageomin Portezuelo

Nevados de Chillan - the lava flow during the day on 14.07.2020 - webcam Sernageomin Portezuelo

Also in Chile, on July 14, 2020 at 6:59 am local time, the National Geology and Mining Service recorded an earthquake related to rock fracturing, with a local magnitude of 3.0 and a depth of 0.2 km at Taapaca volcanic complex.

The Complex (5,861 m above sea level) is located on the high plateau of the Arica and Parinacota region, and is in 35th place in the classification of specific risks.

 The Taapaca volcanic complex - photo Daniel Bertin / Sernageomin

The Taapaca volcanic complex - photo Daniel Bertin / Sernageomin

The Complex (5,861 m above sea level) is located on the high plateau of the Arica and Parinacota region, and is in 35th place in the classification of specific risks.

Named locally Nevados de Putre, it corresponds to an elongated volcanic complex with an irregular profile, located on the western edge of the current volcanic front of the central Andes. Its activity dates back 2.7 million years with the emission of lava and mainly andesitic pyroclasts.

Over the past 1.5 million years, eruptive activity has migrated approximately 4 to 5 km to the southwest, limited to short periods of activity and separated by prolonged stages of immobility.

There is no record of historical eruptive activity. There are only hot springs and sulfur deposits associated with this eruptive center.

The alert level remains green; A potential reactivation would be linked to the location of the dacitic domes and to the subsequent generation of pyroclastic currents which would most likely affect the southwest flank of the volcano, the area where Putre is located, the main populated center of the altiplano region. (about 2,000 inhabitants), and the international route CH-11.

 

Source: Sernageomin

 Bulusan - photo archive 2016.10.08 / PHIVOLCS-SPDRRMO

Bulusan - photo archive 2016.10.08 / PHIVOLCS-SPDRRMO

The Phivolcs recorded since July 13 an increase in the number of volcanic earthquakes in Bulusan: it counts 33 in 24 hours on the 13th and 27 earthquakes in 24 hours on the 14th (period from 8h to 8h morning)

A very low emission of white plumes charged with vapor from the southeast vents was observed. Ground deformation data from continuous GPS measurements indicate short-term inflation of the building since late February 2020. These parameters indicate that volcanic processes are underway under the building which may be caused by deep degassing or hydrothermal activity or magmatic intrusion.

People living in the valleys and along the river canals, especially in the south-east, south-west and north-west of the building, must be vigilant against flows and lahars laden with sediment in case of strong prolonged rains.

Level 1 (abnormal) alert status currently prevails over Bulusan volcano, which means that it is currently in an abnormal state.

 

Source: DOST-PHIVOLCS

Iceland - earthquakes at 15.017.2020 / 07.35 am - Doc. IMO
Iceland - earthquakes at 15.017.2020 / 07.35 am - Doc. IMO

Iceland - earthquakes at 15.017.2020 / 07.35 am - Doc. IMO

Vatnajökull / Bárðarbunga - magnitude of the earthquakes on 15.07.2020 - the two earthquakes of more than M3 in the night of 13-14.07.2020 - Doc. IMO

Vatnajökull / Bárðarbunga - magnitude of the earthquakes on 15.07.2020 - the two earthquakes of more than M3 in the night of 13-14.07.2020 - Doc. IMO

Shortly before midnight on July 13 at 11:41 p.m. an earthquake of magnitude 3 shook the southeastern part of the Bárðarbunga caldera and about an hour later on July 14, another earthquake of magnitude 3.6 shook the region.

Earthquakes of this magnitude are common in Bárðarbunga.

 

Note that the seismic swarms continue in the Reykjanes peninsula, around Grindavik, and further north, at the mouth of the Eyjafjördur; In the north, there are more than 13,000 earthquakes, 3 of which are greater than 5.

 

Source: IMO

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
Etna - 11.07.2020 - strombolian activity at the "Saddle vent" of the SEC, view of Piano del Vescovo - photo INGVvulcani

Etna - 11.07.2020 - strombolian activity at the "Saddle vent" of the SEC, view of Piano del Vescovo - photo INGVvulcani

A weak Strombolian activity was observed this July 11, 2020 in the evening at the saddle vent located between the new and the old southeast cone of Etna.

 

Source: INGVvulcani

Etna - 12.07.2020 / 06h27 - INGV OE Emot0129 webcam

Etna - 12.07.2020 / 06h27 - INGV OE Emot0129 webcam

A new eruptive episode is reported in Suwanosejima this July 12 at 11:53 am local; it was accompanied by a plume at 1,300 meters above the active crater, drifting to the northeast.

 

Sources: JMA & VAAC Tokyo

Suwanosejima - 12.07.2020 / 11h49 & 11h54 - doc. JMA

Suwanosejima - 12.07.2020 / 11h49 & 11h54 - doc. JMA

Activity fell on Nishinoshima on July 11 and 12.

A slight thermal anomaly remains, but has decreased considerably since July 10, when it was noted at VRP 1340 at 473 MW, against VRP 91 at 8 MW on July 11.

The extension of the plume is centered around the island, with a moderate drift towards the northeast.

 

Sources: Mirova, VAAC Tokyo and Nasa Worldview

Nishinoshima - decrease in thermal anomalies and radiative power - Doc. Mirova on 11.07.2020 / 1.15 p.m. - one click to enlargeNishinoshima - decrease in thermal anomalies and radiative power - Doc. Mirova on 11.07.2020 / 1.15 p.m. - one click to enlarge

Nishinoshima - decrease in thermal anomalies and radiative power - Doc. Mirova on 11.07.2020 / 1.15 p.m. - one click to enlarge

Nishinoshima - 12.07.2020 - Nasa worldview satellite image and Volcanic ash advisory by VAAC Tokyo.
Nishinoshima - 12.07.2020 - Nasa worldview satellite image and Volcanic ash advisory by VAAC Tokyo.

Nishinoshima - 12.07.2020 - Nasa worldview satellite image and Volcanic ash advisory by VAAC Tokyo.

Earthquakes continue in Iceland at the mouth of Eyjafjörður in the north and on the Reykjanes peninsula in the southwest.

 

The seismic swarm at the mouth of Eyjafjörður is still in progress. Since the crisis began on June 19, the National Meteorological Office's earthquake system has located more than 13,000 earthquakes, including three magnitude 5 earthquakes.

There are still many small earthquakes in the region and it is still likely that there will be more larger earthquakes.

 Iceland - earthquakes at 12.07.2020 / 07:15 a.m. - IMO
 Iceland - earthquakes at 12.07.2020 / 07:15 a.m. - IMO
 Iceland - earthquakes at 12.07.2020 / 07:15 a.m. - IMO

 Iceland - earthquakes at 12.07.2020 / 07:15 a.m. - IMO

Yesterday, two earthquakes of more than magnitude 3 were measured just west of Herðubreiðartöglar on the Reykjanes peninsula.

The first of magnitude 3.2 at 2:15 p.m. and the second at 5:47 p.m. of magnitude 3.1, but a report was received that the second earthquake was found in Drekagil by Askja.

Earthquakes have persisted in the Grindavík region in recent months due to landslides.

 

Source: IMO

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
Asama - 06.27.2020 / 3:42 p.m. loc. - Osasa Camera, Maechan Net

Asama - 06.27.2020 / 3:42 p.m. loc. - Osasa Camera, Maechan Net

The J.M.A. raised the alert level of Asama, on the island of Honshu in Japan, to 2 / do not approach the crater, on June 25 at 3 p.m. JST. It is advised not to enter the danger zone in the municipalities of Gunma: Tsumagoi-mura, Nagano: Komoro-shi, Karuizawa-machi, Miyota-machi.

Since June 20, seismic activity on the western flank of the volcano has continued at fluctuating levels. On June 24 and 25, the seismic station recorded 59 and 69 volcano-tectonic earthquakes respectively.

An eruption could occur without warning.

The warning bulletin indicates that the ballistic impacts of volcanic bombs and pyroclastic flows could affect an area about 2 km away from the main crater.

Asama - Topography - doc. K. Nakajima / Geological Survey of Japan

Asama - Topography - doc. K. Nakajima / Geological Survey of Japan

Asama could be involved in the famine that marked Europe between 1108 and 1113, according to a recent study on the sulphate deposits of the last millennium in the ice cores of Greenland.

Long considered the product of the 1104 CE Hekla (Iceland) eruption, this event can now be associated with significant deposits observed in Antarctica according to a chronology revised in the same way.

Several closely spaced volcanic eruptions occurred between 1108 and 1110 CE. The sources of these eruptions remain unknown, but the study suggests that Mount Asama, the largest eruption of the Holocene occurred in August 1108 CE (Global Volcanism Program / Asama - eruption of 29.08.1108 at October 1108 - VEI 5 ​​confirmed), and is credibly documented by a contemporary Japanese observer, as a plausible contributor to the high concentration of sulfate in Greenland.

The dendroclimatological data and the historical documentation also attest to serious climatic anomalies following the proposed eruptions, which provided the environmental conditions prior to the subsistence crises experienced in Western Europe between 1109 and 1111 CE.

 

Sources:

- Global Volcanism Program - Asama - eruptive history - link

- Nature - Scientific reports - Guillet, S., Corona, C., Ludlow, F. et al. Climatic and societal impacts of a “forgotten” cluster of volcanic eruptions in 1108-1110 CE. Sci Rep 10, 6715 (2020). - link

- Surveillance cameras - thanks to Yukio Hayakawa

Onioshi camera, Japan Meteorological Agency
Kurogayama Camera, Nagano Prefecture Saku Construction Office
Osasa Camera, Maechan Net
Dodaira Camera, Tokigawa City, Saitama Prefecture

Nishinoshima - 06.26.2020 - strong SO2 signal (38.72DU of SO2 at an altitude of 7.17km. - Doc. Sentinel-5P Tropomi / DLR / BIRA / ESA

Nishinoshima - 06.26.2020 - strong SO2 signal (38.72DU of SO2 at an altitude of 7.17km. - Doc. Sentinel-5P Tropomi / DLR / BIRA / ESA

The VAAC Tokyo reports this June 26 at 12h Z that ash emissions continue in Nishinoshima. Confirmed at an eastward flight altitude of 100 / Himawari-8 satellite data.

A strong sulfur dioxide signal was detected on June 26 from 38.72 DU of SO2 at an altitude of 7.1 km northeast, via Sentinel- 5P / Tropomi.

 

Sources: VAAC Tokyo and Sentinel-5P / Tropomi

Nishinoshima - Volcanic Ash Advisory 26.06.2020 - Doc. VAAC Tokyo

Nishinoshima - Volcanic Ash Advisory 26.06.2020 - Doc. VAAC Tokyo

Ebeko - ash plume - Doc. ASTv / Photo by Sergey Lakomov / 27.06.2020

Ebeko - ash plume - Doc. ASTv / Photo by Sergey Lakomov / 27.06.2020

A moderate eruptive activity continues at the Ebeko, in the Kurils.

According to observations by volcanologists at Severo-Kurilsk, the explosions were accompanied by ash plumes at 2,200 meters asl. on June 25, 2,500 meters asl. on June 26 and more than 1,900 meters asl. on June 27.

The aviation color code remains orange.

 

Source: KVERT

 Tjörnes FZ - location and magnitude of earthquakes at 27.06.2020 / 07:15 - Doc. IMO
 Tjörnes FZ - location and magnitude of earthquakes at 27.06.2020 / 07:15 - Doc. IMO
 Tjörnes FZ - location and magnitude of earthquakes at 27.06.2020 / 07:15 - Doc. IMO

Tjörnes FZ - location and magnitude of earthquakes at 27.06.2020 / 07:15 - Doc. IMO

The seismic swarm in the Tjörnes fracture zone, north-east of Siglufjörður, is still in progress.

During the night of June 27 at 4:52 p.m., an earthquake of magnitude 4.0 was measured at approximately 35 km NNE from Siglufjörður, this morning at 6:02 a.m., another of magnitude 3.2 was measured at approximately 20 km northeast of Siglufjörður.

Yesterday, June 26, the automatic system measured more than 700 earthquakes in the region, an earthquake> 3.0 was detected yesterday at a magnitude of 3.2 at 1:55 p.m. about thirty kilometers northeast from Siglufjörður.

Since the crisis began on June 19, the National Meteorological Office's earthquake system has located about 7,000 earthquakes. Three earthquakes of more than 5 were detected in the hryvnia, the largest on Sunday evening at 7:07 pm magnitude 5.8 at 30 km from Siglufjörður. Other earthquakes larger than 5 were 5.6 and 5.4 and were located more than 20 km NE from Siglufjörður.

Many smaller earthquakes are still measured in the region, and larger earthquakes are likely to occur.

 

Source: IMO - Scientist on duty on 27.06.2020 / 6:17 am

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
 Ebeko - photo Y.Demyanchuk / via RIA Novosti 22.06.2020

Ebeko - photo Y.Demyanchuk / via RIA Novosti 22.06.2020

A moderate eruptive activity is reported by KVERT to the Ebeko on June 21 and 22, 2020, observed by volcanologists from Severo-Kurilsk; it is characterized by explosions which are accompanied by ash plumes at more than 2,000-2,200 meters asl., drifting over 5 km towards the south of the volcano.

 

Source: KVERT - KSCNET & VAAC Tokyo

Sangay - photo archive IGEPN / Patricio Ramon

Sangay - photo archive IGEPN / Patricio Ramon

The levels of surface and internal activity of Sangay in Ecuador remain high, without change.

This June 21, the volcano remains hidden by the clouds, but the VAAC Washington reports gas and ash emissions at 570 meters above the crater, drifting west.

The SAGA seismic station recorded a high frequency signal which is surely associated with the descent of mudslides and debris (lahars).

This phenomenon has been recurrent since the start of activity in May 2019 and is due to the fact that the intense rains over the volcano remobilize the material accumulated during these months of activity. It is recommended not to be in the areas close to the banks of the Volcán and Upano rivers.

In the past 24 hours (20.06 to 21.06 / 11h), the IGEPN reports 8 LP earthquakes, 72 explosions and 8 episodes of emission tremor.

 2019.11.05 Reventador - photo archive IGEPN / Silvana Hidalgo 05.11.2019

2019.11.05 Reventador - photo archive IGEPN / Silvana Hidalgo 05.11.2019

At Reventador, the surface activity is moderate, the internal activity remains high on June 21, 2020.

The cloudiness prevents observation; the VAAC Washington reports during the night of June 20 an emission of gas and ashes at 1,338 meters above the crater, drifting towards the west.

Incandescence is observed at night during the thinnings, as well as falling blocks on the flanks of the volcano over 600 meters.

The IGEPN reports, for the last 24 hours, 23 LP earthquakes, 15 explosions, 5 episodes of emission tremor and 3 of harmonic tremor

 

Sources: IGEPN & VAAC Washington.

Kanlaon - photo Phivolcs

Kanlaon - photo Phivolcs

The Kanlaon Volcano seismic monitoring network recorded one hundred thirty-six volcano-tectonic earthquakes on the western flanks during the latest 24-hour observation period. Four (4) of these earthquakes at 1:01, 1:04, 1:34 and 2:06 were recorded at M3.2-4.7 by the Philippine Seismic Network and were felt at intensities II to V in La Carlota and Bago City, Negros Occidental and Canlaon City, Negros Oriental.

A moderate emission of white plumes loaded with vapor, reaching 200 meters in height, is observed above the crater, before drifting towards the southwest.

Sulfur dioxide emissions were measured at an average of 438 tonnes / day on June 13, 2020. Soil deformation data from continuous GPS measurements indicate inflation on average slopes since April 2020. These parameters indicate that a hydrothermal or magmatic activity occurs under the building.

 

DOST-PHIVOLCS would like to remind the public that the Kanlaon volcano is on alert level 1, which means that it is in an abnormal state and has entered a period of unrest. Local authorities and the public are strongly reminded that entry into the permanent danger zone (PDZ) with a radius of 4 kilometers must be strictly prohibited due to the additional possibilities of sudden and dangerous eruptions of vapor or phreatics.

Source: Phivolcs - 22.06.2020 / 8h

 Tjörnes Fracture zone - location of the seismic swarm and magnitude of earthquakes - Doc. IMO on 06.22.2020
 Tjörnes Fracture zone - location of the seismic swarm and magnitude of earthquakes - Doc. IMO on 06.22.2020
 Tjörnes Fracture zone - location of the seismic swarm and magnitude of earthquakes - Doc. IMO on 06.22.2020

Tjörnes Fracture zone - location of the seismic swarm and magnitude of earthquakes - Doc. IMO on 06.22.2020

The seismic swarm in the Tjörnes fracture zone in northern Iceland continues.

These swarms are common ... what is less so is the unusual high energy released, with more than 70 earthquakes of magnitude greater than 3, the largest reaching M 5.6 and 5.7. In total, the IMO has located more than 2,000 earthquakes since the start of this crisis.

He also reports considerable rock collapses in Tröllaskagi, but also accident reports in Malmö. A power outage in Kelduhverfi was also reported after the second earthquake.

There is a considerable risk of rock accidents and landslides on steep slopes in the northern fjords and on the Tröllaskagi and Flatey Islands. It is important that travelers in the mountains and those traveling in a steep country are aware of the danger of accidents and landslides.

Civil defense has declared the level of uncertainty in the northeast from the start of this seismic swarm.

 

The seismic swarm is still in progress and may move east along the Húsavík-Flateyjarm gang. Larger earthquakes cannot be excluded ... earthquakes of magnitude up to 7 are known in the Húsavík-Flateyjarmenggang. In 1872, there were two earthquakes of magnitude M6.5 and in 1755, an earthquake estimated at M7.

 

Source: IMO - Veðurstofa Íslands

 Tjörnes fracture zone - Rocks fall and landslides - photo 21.06.2020 Veðurstofa Íslands

Tjörnes fracture zone - Rocks fall and landslides - photo 21.06.2020 Veðurstofa Íslands

 NVZ / Northern volcanic zone map - with principal faults and historic earthquakes - via Gisli Olafsson

NVZ / Northern volcanic zone map - with principal faults and historic earthquakes - via Gisli Olafsson

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
 Popocatépetl - 02.05.2020 / 11h04 gas and ash exhalation - WebcamsdeMexico

Popocatépetl - 02.05.2020 / 11h04 gas and ash exhalation - WebcamsdeMexico

Cenapred has identified over the past 24 hours at Popocatépetl 142 exhalations and small explosions, accompanied by gas emissions and small amounts of ash, which continued during the day.

A total of 491 minutes of tremor was recorded.

Night glow marked the summit of the volcano, visible on the webcams from 9 p.m. to more than 10:30 p.m.

The volcanic alert remains at amarillo Fase 2.

 

Sources: Cenapred and webcamsdeMexico.

Popocatépetl - incandescence 02.05.2020 / 21h09 - WebcamsdeMexico

Popocatépetl - incandescence 02.05.2020 / 21h09 - WebcamsdeMexico

In Chile, the Sernageomin reports this May 2, 2020 at 7:33 p.m. local to the Puyehue-Cordon Caulle volcanic complex a volcanotectonic earthquake of M loc. 3.0 / depth 3.1 km, associated with the fragmentation of rocks.

The technical alert remains unclear.

The last period of activity dates back to June 2011 - April 2012, characterized by an VEI 5.

 

Source: Sernageomin / OVDAS & Global Volcanism Program

This series of images includes: a) a location map of Puyehue-Cordón Caulle; b) a NASA ALI image taken on January 26, 2012, including the annotated locations of the observation points (red star) and the red box corresponds to the area in "c"; c) the overlapping ventilation structures and ash plumes were captured on this GeoEye-1 image from July 3, 2012; (d) and this panorama of the active lava flow observed on January 10, 2012 (note that the scale is approximate). The original images are from Schipper et al., 2013. / GVP

This series of images includes: a) a location map of Puyehue-Cordón Caulle; b) a NASA ALI image taken on January 26, 2012, including the annotated locations of the observation points (red star) and the red box corresponds to the area in "c"; c) the overlapping ventilation structures and ash plumes were captured on this GeoEye-1 image from July 3, 2012; (d) and this panorama of the active lava flow observed on January 10, 2012 (note that the scale is approximate). The original images are from Schipper et al., 2013. / GVP

In Shishaldin, on advisory volcanic alert and Yellow aviation code, the troubles continue with possible sulfur dioxide emissions detected by satellite and vapor in the crater visible on high resolution satellite images. The views of the web cameras were obscured by the clouds and no significant activity was detected on local seismic stations or regional infrared sensors. Although disturbances are currently at low levels, activity could intensify with little warning, and additional eruptive activity in the summit crater, lava flows, lahars and ash-producing eruptive events could happen.

The Shishaldin is monitored by local seismic and infrasound sensors, satellite data, web cameras, a telemetric geodetic network and remote infrasound and lightning networks.

 

Sources: AVO / 02.05.2020 and Pierre Markuse.

Shishaldin - Sentinel-2 enh image. Nat. Colors + IR overlay / 04.29.2020 - via Pierre Markuse - one click to enlarge

Shishaldin - Sentinel-2 enh image. Nat. Colors + IR overlay / 04.29.2020 - via Pierre Markuse - one click to enlarge

An earthquake with a magnitude of 6.7 and a depth of 10 km. was located by the INGV Tsunami Warning Center (CAT) and EMSC at 12.51 UTC on May 2, 2020. The epicenter is located at sea, about 80 km south of the island of Crete.

The pushing mechanism suggests a break on the subduction interface at shallow depth.

Due to the magnitude, a red tsunami alert (Watch) was issued by the CAT-INGV for the island of Crete, while the alert level is orange (Advisory) for the other regions of Greece, for Turkey, Libya and Egypt. The warning message was issued by CAT-INGV eight minutes after the earthquake.

The CAT-INGV issued a confirmation message of the tsunami, which was observed at the tide gauge of Ierapetra on the island of Crete, although with a extent hitherto limited (approximately 15 cm, or approximately 35 cm at peak). Technically speaking, a sea level change caused by an earthquake has occurred, so it is indeed a tsunami, although small, it caused whirlpool and currents in ports and on beaches.

 

A strong aftershock occurred at 13:33 UTC, characterized by an M 5.3 and a depth of 30 km.

 

Sources: EMSC & CAT-INGV

South Crete - earthquakes of 02.05.2020 / 12.51 and 13.33 UTC - Doc. EMSC
South Crete - earthquakes of 02.05.2020 / 12.51 and 13.33 UTC - Doc. EMSC

South Crete - earthquakes of 02.05.2020 / 12.51 and 13.33 UTC - Doc. EMSC

Earthquake of 02.05.2020 south of crete - location and sea level at Ierapetra (tsunami) - Doc. Dr. Heidarzadeh / Brunel Univ. London

Earthquake of 02.05.2020 south of crete - location and sea level at Ierapetra (tsunami) - Doc. Dr. Heidarzadeh / Brunel Univ. London

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
 Klyuchevskoy - 04.26.2020 / 3:16 p.m. UTC - IVS FEB RAS KVERT 

 Klyuchevskoy - 04.26.2020 / 3:16 p.m. UTC - IVS FEB RAS KVERT 

The KVERT confirms continuous activity at the Klyuchevskoy on April 27, of Strombolian type, with a lava flow on the south-eastern flank of the volcano, the Apakhonchich chute, phreatic bursts and the slag collapse accompanying these emissions.

The plume is noted at 5,500-6,000 meters asl., extending over 424 km to the northwest of the volcano.

The aviation code remains orange.

 

Sources: KVERT & VAACTokyo

April 26, 2020, ~ Eruption/Lava Flow time lapse ~ Klyuchevskoy Volcano, Russia

Klyuchevskoy - Volcanic Ash Advisory for 27.04.2020 - Doc. VAAC Tokyo

Klyuchevskoy - Volcanic Ash Advisory for 27.04.2020 - Doc. VAAC Tokyo

During the night, from 03.51 h 26.04.2020, a seismic swarm took place in the area of ​​the Phlegraean Fields of the Solfatara-Pisciarelli, consisting of a sequence of 34 tremors of magnitude between 0.0 and 3.1 , and with hypocentres between 1 and 2 km. The earthquakes were felt in the Pozzuoli region.

The seismologists of the Vesuvius Observatory (Naples Section of the INGV), who analyzed the events, did not detect any anomalies regarding the current development of the current bradisismic crisis. It is recalled that the appearance of seismic swarms normally occurs during a period characterized by bradisismic activity, such as that underway in the Phlegrean Fields since 2005. There are elements of novelty in the progression of the current phenomenon . The geochemicals of the Vesuvius Observatory are at work to carry out surveys on the fumaroles of the Solfatara-Pisciarelli area, and report that there have been no new mouths opened.

 

Sources: INGVvulcani, INGV osservatorio Vesuviano, and Associazione Italiana di Vulcanologia (AIV)

Phlegraean fields - location of earthquakes of the last days and seismogram of 04.26.2020 - Doc. INGVvulcani and seismogram statio Solfatara south edge / radsalerno.altervista.org
Phlegraean fields - location of earthquakes of the last days and seismogram of 04.26.2020 - Doc. INGVvulcani and seismogram statio Solfatara south edge / radsalerno.altervista.org

Phlegraean fields - location of earthquakes of the last days and seismogram of 04.26.2020 - Doc. INGVvulcani and seismogram statio Solfatara south edge / radsalerno.altervista.org

A total of 18 people, including 13 guards and drivers from Virunga National Park in the Democratic Republic of the Congo were killed on Friday April 24 in an ambush by militiamen. It is the deadliest attack in recent years in this sensitive region of Upper Kivu.

We must remember the ambush of April 2014, in which Emmanuel de Merode, National Park curator, anthropologist and Belgian primatologist was seriously injured. Inaugurated in 1925, the park has since suffered repeated attacks by rebel groups, militiamen and poachers.

Virunga Volcanoes - image ESA Virunga Mountains / 2016.11.11

Virunga Volcanoes - image ESA Virunga Mountains / 2016.11.11

Respect to these rangers who protect mountain gorillas, and biodiversity, risking their lives, and condolences to the families of the victims of barbarism.

The park management declares that these tragic events will not stop the development programs carried out for the benefit of the neighboring communities, who aspire to live in an atmosphere of justice and peace.

 

Source: Virunga National Park - https://virunga.org/fr/news/updated-statement-from-virunga-national-park-on-recent-attack

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
 Piton de La Fournaise - 04.04.2020 / 9.47am - HD / OVPF / IRT panoramic camera

Piton de La Fournaise - 04.04.2020 / 9.47am - HD / OVPF / IRT panoramic camera

At the Piton de La Fournaise, the eruption which started on 02.04.2020 on the eastern flank of the Piton de la Fournaise, around 12:20 local time, continues. The intensity of the volcanic tremor (indicator of the intensity of the eruption) has been relatively stable over the past 12 hours.

On April 3, at 6:25 a.m., the lava front could be estimated at around 1,000 m above sea level at the top of the Grandes Pentes, and 3.8 km from the national road, according to visual feedback from the webcam of the OVPF / IPGP located in Piton Cascades.

The eruption has stabilized on the central part of the eruptive fissure. The number of fountains is reduced little by little and soon the eruption will only be active on one or two mouths. In the meantime, the projected pieces of lava fall back and build a spatter-rampart which has already grown well.

On April 3 at 10:15 p.m., the thermal anomaly noted by Mirova was VRP 2607 MW (probably due to a thinning)

Note that during the lateral magma intrusion towards the eruptive site on April 2, between 8:50 am and 12:20 pm, and following the seismic crisis (8:15 am - 8:51 am), the deformations and seismicity were extremely weak. The lateral propagation was thus done in a fairly "passive" way in an already open environment and extremely weakened by the eruptions of 2019 and the eruption of February 10-16, 2020 which took place in this sector.

Piton de La Fournaise - Spatter-rampart under construction - rb photo / ImazPress Réunion 03.04.2020

Piton de La Fournaise - Spatter-rampart under construction - rb photo / ImazPress Réunion 03.04.2020

Piton de La Fournaise - Evolution of the RSAM (indicator of the volcanic tremor and the intensity of the eruption) since 02/04/2020 at 00h UT time (04h local time) on the DSO seismological station located at the top of the volcano. (© OVPF / IPGP).

Piton de La Fournaise - Evolution of the RSAM (indicator of the volcanic tremor and the intensity of the eruption) since 02/04/2020 at 00h UT time (04h local time) on the DSO seismological station located at the top of the volcano. (© OVPF / IPGP).

The CO2 fluxes in the far field soil (Plaine des Cafres / Plaine des Palmistes sectors) fell between 28/3 and 01/4 before increasing again. This could correspond to an expulsion of superficial magma (superficial reservoir) by a rise of deeper magma.

SO2 air flows have dropped since yesterday. This drop is in agreement with the visual feedback from the eruptive site which shows weaker activity today.

The estimated surface flows, from satellite data via the HOTVOLC platform (OPGC - University of Auvergne) are greatly disturbed by the cloud cover around the Piton de la Fournaise. Estimates since the start of the eruption fluctuate between 2 and 45 m³ / s with an average around 7-10 m³ / s.

 

Source: OVPF

 

Find all the information relating to the activity of Piton de la Fournaise on the various media of the OVPF-IPGP:
- the website (http://www.ipgp.fr/fr/ovpf/actualites-ovpf),
- the Twitter account (https://twitter.com/obsfournaise?lang=fr),
- and the facebook account (https://www.facebook.com/ObsVolcanoPitonFournaise/)

Piton de La Fournaire - measurement of the SO2 mass by Sentinel-5P Tropomi on 03.04.2020: 6.15 kt - Doc. Tropomi / DLR / BIRA / ESA

Piton de La Fournaire - measurement of the SO2 mass by Sentinel-5P Tropomi on 03.04.2020: 6.15 kt - Doc. Tropomi / DLR / BIRA / ESA

Piton de La Fournaise - 03.04.2020 / 5:05 pm UT - OVPF webcam Piton de Bert

Piton de La Fournaise - 03.04.2020 / 5:05 pm UT - OVPF webcam Piton de Bert

This Friday, April 03 at 04.17 local time, an earthquake of local magnitude 2.8 located 3.2 km deep was recorded under the summit of the Chaitén volcano. The National Service of Geology and Mines has indicated that this earthquake is associated with rock fracturing and the dynamics of internal fluids (hybrid earthquake). The volcanic technical alert remains on "verde".

The last period of activity of the Chaiten occurred between May 2, 2008 and May 31, 2011 (GVP). This first historic eruption produced major explosive rhyolitic activity, numerous pyroclastic flows and lahars, and was followed by the installation of a dome complex which filled much of the caldera.

 

Sources: Sernageomin & Global Volcanism Program

The eruptive plume of the Chaitén volcano - photo Patricia Santini M / 10.05.2008

The eruptive plume of the Chaitén volcano - photo Patricia Santini M / 10.05.2008

GPS measurements, along with detailed analysis and model calculations of the available data, now testify to a new magma deposit west of the Reykjanes Peninsula under Rauðhólar and Sýrfell.

The map shows the location of the magmatic deposits which would have occurred during the year on the Reykjanes peninsula. These are preliminary results and the models are simplified, but will be updated as data is received. The map indicates when the intrusions were formed - 1. in orange: January 2020 - 2. in red: February-March 2020 - 3. in green: March-April 2020. - Doc. IMO

The map shows the location of the magmatic deposits which would have occurred during the year on the Reykjanes peninsula. These are preliminary results and the models are simplified, but will be updated as data is received. The map indicates when the intrusions were formed - 1. in orange: January 2020 - 2. in red: February-March 2020 - 3. in green: March-April 2020. - Doc. IMO

This confirms the data that was collected in collaboration with the Institute of Earth Sciences, ÍSORs, HS Energy and the Icelandic Meteorological Office after the start of activities in Thorbjörn.

"The data we have processed indicates that the magma intrusion took place from mid-February to the first week of March. This image was better explained when we received data from GPS measurements from the University, which are not directly linked to our monitoring system, which means that we have not detected them so far, "says Kristín Jónsdóttir, group director of nature conservation at the Icelandic Meteorological Office.

One model places the magmatic intrusion about 8-13 km deep, which is probably deep in the earth's crust at a depth considerably higher than the two magma deposits at Thorbjörn.

"This magma deposit under Sýrfell is the third magma deposit that we have reported on the Reykjanes peninsula since the beginning of the year. The presence of this magma insert shows that it is necessary to examine activity on the peninsula Reykjanes globally, not just local activity around Svartsengi and Reykjanes, " said Kristín Jónsdóttir. It reiterates that it is too early at this stage to draw solid conclusions and underlines the need to examine the current activity in a historical context with other known events in the Reykjanes peninsula.

Rauðhólar (icelandic Red hills) - photo Roman Z / wikipedia

Rauðhólar (icelandic Red hills) - photo Roman Z / wikipedia

Rauðhólar (the Icelandic red hills):

Remains of a group of pseudocraters in the Elliðaárhraun lava fields on the south-eastern outskirts of Reykjavik, Iceland. Rauðhólar's age is around 5200 years. Originally there were more than 80 craters, but their gravel was taken and used in construction. Most of the equipment was taken away during the Second World War for constructions such as Reykjavík Airport and road construction.

 

Source: IMO

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
Nevados de Chillan - 29.03.2020 / 9.44 p.m. - Webcam Sernageomin

Nevados de Chillan - 29.03.2020 / 9.44 p.m. - Webcam Sernageomin

At the Nevados de Chillan volcanic complex, explosive activity was recorded on March 29 at around 6:38 p.m. local, with a scattering of ash at low altitude in an east-southeast direction.

It continued on March 30, with grayish emissions reaching a maximum of 1,400 meters.

Volcano-tectonic earthquakes dominate at the seismicity level.

The technical alert is maintained in Amarilla

 

Sources: Sernageomi & Volcanes de Chile

Stromboli - 03.31.2020 - lava overflow in the Scira del Fuoco, at 2:35 and 4:47 respectively - SPCT / INGV OE webcam
Stromboli - 03.31.2020 - lava overflow in the Scira del Fuoco, at 2:35 and 4:47 respectively - SPCT / INGV OE webcam

Stromboli - 03.31.2020 - lava overflow in the Scira del Fuoco, at 2:35 and 4:47 respectively - SPCT / INGV OE webcam

The National Institute of Geophysics and Volcanology, Etnean Observatory, informs that the surveillance networks recorded from 23:40 hours UTC approximately on March 30, 2020, a lava overflow from the crater terrace of Stromboli; lava reached the coast line at approximately 1:50 a.m. UTC on March 31.

At the same time as volcanic phenomenology, there is a seismic signal associated with episodes of rolling incandescent blocks along the Sciara del Fuoco and small landslides that generate clouds of dust.

 

Sources : INGV OE & L.G.S.

Stromboli - lava flow in Sciara del Fuoco - 31.03.2020 / à   01h45 and  6h48  -Doc. LGS

Stromboli - lava flow in Sciara del Fuoco - 31.03.2020 / à 01h45 and 6h48 -Doc. LGS

Stromboli - sismogram 31.03.2020 between 01h and 6h45 - Doc. Seismo-acoustic network LGS

Stromboli - sismogram 31.03.2020 between 01h and 6h45 - Doc. Seismo-acoustic network LGS

Sabancaya - summary of the activity between 23 and 29 March 2020 - Doc. I.G.Peru

Sabancaya - summary of the activity between 23 and 29 March 2020 - Doc. I.G.Peru

The eruptive activity of the Sabancaya volcano remained at moderate levels between March 23 and 29, with the continuous recording of moderate explosions and the consequent emission of ash and gas. Consequently, for the following days, no significant change is expected regarding its activity.

During the aforementioned period, the IGP recorded and analyzed the occurrence of approximately 536 earthquakes of volcanic origin, associated with the circulation of fluids (magma, gas, etc.) inside the volcano and accompanied columns of gas and ash up to 3 km high above the summit of the volcano, scattered towards the western, southwest and southern sectors of Sabancaya.

In addition, 16 medium to low intensity daily explosions were recorded on average. The monitoring of the deformation of the volcanic structure records significant anomalies.

Satellite surveillance has enabled the presence of 5 thermal anomalies with values ​​between 2MW and 13 MW, associated with the presence of a surface lava body in the crater of the volcano.

The volcanic alert level in orange and it is recommended not to approach within a radius of 12 km.

 

Source: IG Peru
 

Taal - main crater - taken by drone / Phivolcs archives - Raffy Tima

Taal - main crater - taken by drone / Phivolcs archives - Raffy Tima

In Taal volcano, March 29 was marked by 93 volcanic earthquakes, associated with the fracturing of rocks, including 6 of magnitude between M1.8 and M3.4, felt in the barangays Banyaga, Bilibinwang and Subic Ilaya.

Low emissions of steam plumes are observed at the main crater and at the vents along Daang Kastila Road.

On March 30, the emissions observed reached only 50 to 100 meters in height, drifting to the southwest. THE number of volcanic earthquakes has decreased and is now only 17 events.

The alert level remains at 1 / abnormal; the prohibited zones remain around the main crater and the Daang Kastila crack.

 

Source: Phivolcs

 Reykjanes Peninsula - 30.03.2020 / 5:50 pm - location and magnitude of earthquakes - Doc.IMO
 Reykjanes Peninsula - 30.03.2020 / 5:50 pm - location and magnitude of earthquakes - Doc.IMO

 Reykjanes Peninsula - 30.03.2020 / 5:50 pm - location and magnitude of earthquakes - Doc.IMO

In Reykjanes Peninsula, activity in Grindavík remained high this week after a swarm of earthquakes that started on March 12. This is the same area as where previous earthquake swarms occurred earlier this year.

About 1,000 earthquakes have been located on the Reykjanes Peninsula. The biggest earthquake of the week was M4.2 on March 18, about 5 km NW of Gunnuhver on the Reykjanes Peninsula. The earthquake was widely felt in the southwestern part of Iceland. On March 19, an M3.5 earthquake occurred 3.5 km NW of Grindavík. An M3.0 earthquake occurred on March 20 by Kleifarvatn on the Reykjanes Peninsula, where a small swarm of earthquakes occurred on the same day.

On March 28, 2020, an earthquake swarm occurred on the Reykjanes Ridge. The largest earthquakes in this swarm had a magnitude of Mw3.5. A total of seven earthquakes occurred which were greater than the magnitude Mw3.0.

 

Source: IMO

Reykjanes ridge and peninsula - location and magnitude of the earthquakes of March 29 and 30 / 1:25 p.m. - Doc. IMO
Reykjanes ridge and peninsula - location and magnitude of the earthquakes of March 29 and 30 / 1:25 p.m. - Doc. IMO
Reykjanes ridge and peninsula - location and magnitude of the earthquakes of March 29 and 30 / 1:25 p.m. - Doc. IMO
Reykjanes ridge and peninsula - location and magnitude of the earthquakes of March 29 and 30 / 1:25 p.m. - Doc. IMO

Reykjanes ridge and peninsula - location and magnitude of the earthquakes of March 29 and 30 / 1:25 p.m. - Doc. IMO

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