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Earth of fire

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

sismologia

Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
Anak Krakatau - eruptive episode of 2022.10.27 / 12:06 WIB - Sertung PVMBG webcam

Anak Krakatau - eruptive episode of 2022.10.27 / 12:06 WIB - Sertung PVMBG webcam

Anak Krakatau experienced a new eruptive episode on Thursday October 27, 2022 at 12:05 WIB with the height of the ash column observed at ± 250 m above the summit (± 407 m above sea level). The ash column is observed to be gray with a thick intensity towards the northeast. This eruption was recorded on a seismograph with a maximum amplitude of 37 mm and a duration of 25 seconds.

VAAC Darwin has issued an Orange Aviation Code.
Activity level remains at 3/siaga, with recommendation: Communities/visitors/tourists/climbers do not approach Mount Anak Krakatau or engage in activities within 5 km of the active crater.

 

Sources: PVMBG, Magma Indonesia and VAAC Darwin

Bezymianny -photo archives  Yu. Demyanchuk. IVS FEB RAS, KVERT

Bezymianny -photo archives Yu. Demyanchuk. IVS FEB RAS, KVERT

After its strong explosive eruption on October 23 and 24, the extrusive-effusive eruption of the Bezymianny volcano continues; strong fumarole activity, incandescence of the lava dome at night, and hot avalanches accompany this process. Sometimes the large ash clouds formed after hot avalanches, for example, such a 10x13 km ash cloud moved 70 km east of the volcano on October 26. Likely, the next strong explosive eruption could occur at any time. KVERT continues to monitor the Bezymianny volcano.

 

The extrusive-effusive eruption of the volcano continues, but the activity of the volcano remains very high. Strong ash explosions up to 10-15 km (32,800-49,200 ft) a.s.l. could occur at any time. Ongoing activity could affect international and low-flying aircraft.

Current Aviation Color Code: ORANGE
Previous Aviation Color Code: Yellow

 

Source: KVERT

Suwanosejima - eruption live on 25.10.2022 / 08:28 - Doc. vidéo JMA

The JMA reported that Suwanosejima's Ontake crater eruption continued from October 17-24.

The incandescence of the crater was visible at night. A total of 119 explosions from October 17–21 produced eruption plumes that rose up to 2 km above the crater rim and ejected blocks up to 800 m from the vent. Occasional rumbling and ash fall was reported in Toshima village (3.5 km SSW).

Only one explosion was reported from October 21 to 24. Plumes rose up to 1.5 km and boulders were ejected up to 200 m from the vent. Ash falls were reported in the village of Toshima.

The Alert Level remained at 2 and the public was warned to stay 1 km from the crater.

On October 28, a new episode occurred, filmed live by the JMA

 

Sources: JMA & Global Volcanism Program weekly report

Tungurahua - 26.10.2022 - lahar recorded by Achupashal station - Doc. IGEPN

Tungurahua - 26.10.2022 - lahar recorded by Achupashal station - Doc. IGEPN

This Wednesday, October 26, from approximately 7:00 p.m. TL, the Achupashal station in Tungurahua, Ecuador, recorded seismic signals corresponding to the descent of mudslides and debris (lahars) from the Tungurahua volcano. It is important to highlight that the Baños-Penipe highway crosses the mouth of this ravine, so the circulation of vehicles must be careful in case secondary lahars descend towards said highway.

 

Source: IGEPN – info #2022-002

Iceland - earthquakes on 26.10.2022 / 4:35 p.m. - Doc. IMO
Iceland - earthquakes on 26.10.2022 / 4:35 p.m. - Doc. IMO
Iceland - earthquakes on 26.10.2022 / 4:35 p.m. - Doc. IMO

Iceland - earthquakes on 26.10.2022 / 4:35 p.m. - Doc. IMO

Icelandic Met Office details on earthquakes in Iceland:

About 2520 earthquakes were detected by IMO's SIL seismic network last week, much more than the previous week when about 900 earthquakes were detected. About 980 earthquakes were located manually.

The difference is largely explained by an earthquake swarm near Herðubreið that started on October 22, but swarms are also underway in Reykjanes and Grímsey.

 

The week's largest earthquake was M4.1 near Herðubreið, as part of the ongoing swarm there. This is the largest earthquake detected in the region since the start of the SIL seismic network in 1991. The earthquake was felt in the northern part of Iceland. Another 11 earthquakes of M3.0 or greater were detected this week.

They were located near Herðubreið, Grímsey, Reykjanes and Reykjanes Ridge.

More seismic activity was detected in all regions compared to the previous week, except in Mýrdalsjökull. 20 earthquakes were detected in Grímsvötn and 5 in the Hekla volcano.

Askja system - seismic swarm on 27.10.2022 / 07:35 - Doc. IMO
Askja system - seismic swarm on 27.10.2022 / 07:35 - Doc. IMO
Askja system - seismic swarm on 27.10.2022 / 07:35 - Doc. IMO

Askja system - seismic swarm on 27.10.2022 / 07:35 - Doc. IMO

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
Anak Krakatau - 2022.10.25 / 07:27 WIB - webcam Sertung PVMBG / Magma Indonesia

Anak Krakatau - 2022.10.25 / 07:27 WIB - webcam Sertung PVMBG / Magma Indonesia

Anak Krakatau -25.10.2022 / 18:49 WIB - Lava93 webcam, 1 km from the crater - Magam Indonesia

Anak Krakatau -25.10.2022 / 18:49 WIB - Lava93 webcam, 1 km from the crater - Magam Indonesia

At Anak Krakatau, eruptive activity over the past two days is on the rise.

The main crater plume is white and gray, with fine, medium to thick intensity, about 25-300 meters from the summit.

Seismic observation:
- 4 eruption earthquakes, with an amplitude of 2-50 mm and an earthquake duration of 17-367 seconds.
- 10 emission earthquakes, with an amplitude of 3 to 19 mm and the duration of the earthquake from 11 to 53 seconds.
- 7 harmonic episodes, with an amplitude of 3 to 6 mm and an earthquake duration of 42 to 174 seconds.
- 21 low frequency earthquakes, with an amplitude of 2 to 8 mm and an earthquake duration of 3 to 15 seconds.
- 1 deep volcanic earthquake, with an amplitude of 51 mm, S-P 2.29 seconds and an earthquake duration of 27 seconds.
- 4 episodes of continuous tremor, with an amplitude of 0.5 to 45 mm, dominating 2 mm.

Anak Krakatau - seismicity on 25.10.2022 - Doc. PVMBG Magma Indonesia


The activity level is at 3 / siaga, with recommendation:
People/visitors/tourists/climbers do not approach Mount Anak Krakatau or engage in activities within 5 km of the active crater.

 

Sources: PVMBG, Magma Indonesia

Anak Krakatau - 26.10.2022 / 09:50 WIB- webcam Sertung PVMBG / Magma Indonesia

Anak Krakatau - 26.10.2022 / 09:50 WIB- webcam Sertung PVMBG / Magma Indonesia

Since 11:25 p.m. TL on October 25, 2022, the SAGA seismic station has recorded an increase in seismic energy at the level of the Sangay volcano. This type of high-energy signal (greater than 6,000 counts on average) is similar to that observed during pulses of increased volcanic activity.

At the moment, the GOES-16 satellite is observing an ash emission in a southwesterly direction.

An incandescence is observed, due to the emission of a lava flow on the southeast flank. It is also possible to see the fall of light ash in populated areas near the volcano located to the southwest.

It is recommended to stay informed of official sources in case of new changes.

 

Source: IGEPN

Sangay - summit incandescence and lava flow on the SE flank on 25.10.2022 / 11:42 p.m. - Doc.IGEPN

Sangay - summit incandescence and lava flow on the SE flank on 25.10.2022 / 11:42 p.m. - Doc.IGEPN

Sangay - dispersion of ashes towards the SW - GOES-16 satellite image of 26.10.2022 / 07:20 UTC - Doc. NOAA CIMSS, via IGEPN

Sangay - dispersion of ashes towards the SW - GOES-16 satellite image of 26.10.2022 / 07:20 UTC - Doc. NOAA CIMSS, via IGEPN

Between October 17 and 23, 2022, INGV OE reports that at Vulcano
the maximum temperature of the fumaroles emitted on the outer edges of La Fossa remain at stable and high values, around 375°C.
The CO2 flux in the crater area remains at medium-high values.
The SO2 flux in the crater area is stable at a moderately medium-high level


Geochemistry of fumarolic gases: The concentration of CO2 and He is constant or slightly increasing and remains at an average level. The carbon isotope ratio is constant at high values ​​and the He isotope ratio is stable at medium levels
The CO2 flux at the base of the La Fossa cone and in the Vulcano Porto area: The CO2 fluxes recorded in the Rimessa, C. Sicilia sites always show values ​​above background levels. The P4max site displays average values, while at the Faraglione site there are values ​​close to the bottom.


Geochemistry of thermal aquifers: in the well of Camping Sicilia there are always high values ​​of temperature and conductivity at medium-low levels; in the Bambara well, the level and conductivity values ​​show no significant variations.


Local seismicity: Low rate of occurrence of local micro-seismicity.
Regional Seismicity: No earthquakes with Ml >= 1.0 were located in the Vulcano region last week.
The GNSS network does not show significant variations.

 

Source: INGV OE weekly bulletin 25.10.2022

Vulcano - fumaroles on the edge of the crater of La Fossa - photo archives INGV OE

Vulcano - fumaroles on the edge of the crater of La Fossa - photo archives INGV OE

In total, more than 1,400 earthquakes have occurred in the vicinity of Herðubreið / Askja System since the earthquakes began last Saturday. Apart from the largest 4.1M earthquake that struck on Saturday evening, two recorded magnitudes above 3.

According to Kristín Elísa Guðmundsdóttir, a natural hazard specialist at the Icelandic Met Office, there is no unrest there. Although these series of earthquakes are more intense than usual, there are frequent bursts in the area of ​​the Askja system.

 

Sources: mbls & IMO

Askja system - location of earthquakes on 26.10.2022 / 07:20 - Doc. IMO

Askja system - location of earthquakes on 26.10.2022 / 07:20 - Doc. IMO

Askja system - number and magnitude of earthquakes from 24 to 26.10.2022 / 07:20 - Doc. IMO
Askja system - number and magnitude of earthquakes from 24 to 26.10.2022 / 07:20 - Doc. IMO
Askja system - number and magnitude of earthquakes from 24 to 26.10.2022 / 07:20 - Doc. IMO
Askja system - number and magnitude of earthquakes from 24 to 26.10.2022 / 07:20 - Doc. IMO

Askja system - number and magnitude of earthquakes from 24 to 26.10.2022 / 07:20 - Doc. IMO

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
Bezymianny - thermal anomalies as of 24.10.2022 / 02:50 - Doc.Mirova_MODIS_Latest10NTI

Bezymianny - thermal anomalies as of 24.10.2022 / 02:50 - Doc.Mirova_MODIS_Latest10NTI

A strong explosive eruption occurred on October 23, 2022 at Bezymianny, in the Kamchatka Peninsula. The explosions sent ash up to 10 km a.s.l.; the ash plume extended 10 km east northeast of the volcano.

The explosive eruption of the volcano continues. Ongoing activity could affect international and low-flying aircraft.

KVERT changed the aviation code from Orange to Red at 12:20 UTC.

 

The observatory announces in a new statement on October 23 at 22:05 UTC that the strong explosive eruption of the volcano has ended. Satellite and visual data showed an extensive gas-steam plume to the northeast of the volcano, and a bright thermal anomaly over the volcano.
An extrusive-effusive eruption of the volcano continues. Ongoing activity could affect low-flying aircraft, and the aviation code has changed back to Orange.

 

Source: KVERT

October 23, 2022, ~ Eruption ~ Bezymianny Volcano, Russia ~ 11:00 - 14:00 UTC

In the early hours of the morning of October 22, the Cotopaxi volcano cleared for a moment and a steam emission was observed 1000 meters in a westerly direction. Then the Washington VAAC reported 2 ash emissions with heights up to 2353 meters above the summit in a northeast and west direction.

Seismicity is characterized by 46 Long Period earthquakes, 1 Volcano-tectonic earthquake, and an episode of emission tremor.


Rains were recorded in the area, which did not generate lahar.
For the moment, the volcano sector remains cloudy, which is why visual observations cannot be made. Last night, a slight ash fall was reported at the José Rivas refuge.

On Sunday October 23, the summit of the Cotopaxi volcano appeared, on the Sincholagua camera, with a layer of dark gray ash, the result of the emissions of the previous days.
The October 21 emissions were accompanied by a seismic signal called a volcanic tremor, which lasted 4 hours and then decreased in intensity in the early hours of October 22.
 
The seismicity over 21 hours is characterized by 481 explosion earthquakes, 34 LP earthquakes, 77 episode of tremor of emission, and one in corrélation with a lahar.


The IGEPN announces that light rain has been recorded via the Windy application. A high frequency signal was observed at the BREF seismic station, possibly related to small secondary lahars which are caused by weathering of the ice sheet by the ash cover at the summit.

A slight emission of gas and water vapor was observed at a height of 500 meters above the summit towards the east.

The alert level has been changed to amarilla.

 

Source: IGEPN

Herðubreid region / Iceland - location of the seismic swarm and magnitude of the earthquakes on 24.10.2022/ 06:45 - Doc. IMO
Herðubreid region / Iceland - location of the seismic swarm and magnitude of the earthquakes on 24.10.2022/ 06:45 - Doc. IMO
Herðubreid region / Iceland - location of the seismic swarm and magnitude of the earthquakes on 24.10.2022/ 06:45 - Doc. IMO

Herðubreid region / Iceland - location of the seismic swarm and magnitude of the earthquakes on 24.10.2022/ 06:45 - Doc. IMO

On October 22 at 11:11 p.m., a magnitude 4.1 earthquake was measured, just north of Herðubreid. Notifications have been received by the Meteorological Bureau that the earthquake has been detected in Akureyri. A total of three earthquakes were measured above magnitude 3.

Considerable post-seismic activity was observed in the area overnight, and the Norwegian Meteorological Agency's automatic earthquake system located around 600 earthquakes in the area north of Herðubreid.


Herðubreid is part of the Askja system, which shows certain signs that it is preparing for activity. "I can definitely say that there will be an eruption in this area, but when it will happen it's harder to say," says volcanologist Þorvaldur Þórðarson about the possibility of an eruption at Herðubreid.

The Askja and Grimstvötn systems are in yellow aviation code (Icelandic volcanoes)


Sources:
- IMO by geoscientist on duty on 23 October 08:
- mbls / volcanologist Þorvaldur Þórðarson
- Icelandic volcanoes

Herðubreið - Painting by Sveinn Thorarinsson 1926

Herðubreið - Painting by Sveinn Thorarinsson 1926

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

Chikurachki is an active volcano located in the Kuril Archipelago
It is currently in the eruptive phase and is emitting large amounts of ash.
On October 15, Sentinel-3 detected a massive ash plume about 300 km long drifting in the Pacific.

Chikurachki - Sentinel-3 image dated 15.10.2022 - via Copernicus EU - one click to enlarge

Chikurachki - Sentinel-3 image dated 15.10.2022 - via Copernicus EU - one click to enlarge

Chikurachki - Sentinel-5P Tropomi image from 16.10.2022 / 01:56 - 01:59 - SO2 emissions from Chikurachki (main) and further north, from Alaid - Doc. DLR BIRA ESA via S. Carn - one click to enlarge

Chikurachki - Sentinel-5P Tropomi image from 16.10.2022 / 01:56 - 01:59 - SO2 emissions from Chikurachki (main) and further north, from Alaid - Doc. DLR BIRA ESA via S. Carn - one click to enlarge

Sentinel-5 P Tropomi SO2 data from October 16 (UTC) shows ~5 kilotonnes (kt) of SO2 in the Chikurachki plume, assuming a plume altitude of 5 km. Some SO2 emissions from Alaid have also been detected further north.

A gas-steam activity of the Chikurachki volcano continues. Satellite data from KVERT shows the last ash plume at 1:30 p.m. UTC and a thermal anomaly at 4:32 p.m. UTC on October 16. KVERT continues to monitor the Chikurachki volcano.

The aviation color code was lowered on October 18 to Yellow.

 

Sources: Copernicus Eu and Prof. Simon Carn / Tropomi

Reykjanes ridge - seismic swarm, location and magnitude of earthquakes as of 17.10.2022 / 6:10 p.m. - Doc. IMO
Reykjanes ridge - seismic swarm, location and magnitude of earthquakes as of 17.10.2022 / 6:10 p.m. - Doc. IMO
Reykjanes ridge - seismic swarm, location and magnitude of earthquakes as of 17.10.2022 / 6:10 p.m. - Doc. IMO

Reykjanes ridge - seismic swarm, location and magnitude of earthquakes as of 17.10.2022 / 6:10 p.m. - Doc. IMO

Reykjanes ridge - parameters of the seismic swarm on the ridge on 17.10.2022 - Doc. IMO

Reykjanes ridge - parameters of the seismic swarm on the ridge on 17.10.2022 - Doc. IMO

A new seismic swarm has been detected on the Reykjanes Ridge, submerged and connected to terrestrial eruptions on the Reykjanes Peninsula.

Earthquakes off the Reykjanes peninsula are frequent, but in the absence of deformation measurements at sea, knowledge of the activity remains poor. An eruption took place at Eldey in 1926, so nothing is ruled out

 

Source: IMO, Kristín Jónsdóttir & Dave McGarvie

Piton de La Fournaise - Zoom of the Enclos showing the fissures (black lines) and the associated lava flows (color code) since 2014 and until the beginning of 2022 (the legend indicates the start date of the eruption: YYYYMMDD ). The dotted black lines divide the Enclos into three main areas: Enclos Fouqué Caldera, Grandes Pentes and Grand Brûlé. The black arrow shows the summit of the Dolomieu crater. - references in Source - one click to enlarge

Piton de La Fournaise - Zoom of the Enclos showing the fissures (black lines) and the associated lava flows (color code) since 2014 and until the beginning of 2022 (the legend indicates the start date of the eruption: YYYYMMDD ). The dotted black lines divide the Enclos into three main areas: Enclos Fouqué Caldera, Grandes Pentes and Grand Brûlé. The black arrow shows the summit of the Dolomieu crater. - references in Source - one click to enlarge

Location of Réunion Island (credits WikimediaCommons, the free multimedia repository) and Map of Piton de la Fournaise showing the outline of communes (pink dotted lines) and communes (buildings are in black), roads (yellow lines ), the trails (orange lines), the vegetated areas (in green) and the limits of the Enclos caldera (blue line). The background is a shaded DEM published in 2010 (coordinates are given in meters in the WGS84-UTM 40S system) by the National Institute of Geographic and Forest Information (IGN). The buildings, roads and trails are taken from the TOPO®IGN 2019 BD. The yellow dots are the monitoring stations of the volcano observatory. -  references in Source - one click to enlarge

Location of Réunion Island (credits WikimediaCommons, the free multimedia repository) and Map of Piton de la Fournaise showing the outline of communes (pink dotted lines) and communes (buildings are in black), roads (yellow lines ), the trails (orange lines), the vegetated areas (in green) and the limits of the Enclos caldera (blue line). The background is a shaded DEM published in 2010 (coordinates are given in meters in the WGS84-UTM 40S system) by the National Institute of Geographic and Forest Information (IGN). The buildings, roads and trails are taken from the TOPO®IGN 2019 BD. The yellow dots are the monitoring stations of the volcano observatory. - references in Source - one click to enlarge

Since 1979, the Piton de la Fournaise (Reunion) has erupted on average twice a year, 95% of these eruptions occurring within an uninhabited caldera. However, lava flows have occasionally affected populated areas of the island, such as in 1977 and 1986.

Since 2014, an integrated multinational response based on satellite data to effusive crises has been developed to quickly assess lava flood zone and flow distance.

In 2018, this protocol was implemented as standalone software to provide a lava flow hazard map showing the probability of flow and flow coverage as a function of discharge rate. Since 2019, the short-term hazard map produced is shared with local civil protection in the first hours after the start of an eruption to help with mitigation actions. Multiple exchanges between scientists, the observatory and civil protection have made it possible to improve the hazard map delivered, to ensure a common understanding, a useful and usable product, and to help build effective mitigation strategies. at Piton de la Fournaise. In this work, we illustrate this effective near real-time protocol with case studies and document how the produced short-term risk map was adapted to meet the needs of civil protection.

 

Source and full text: Chevrel, M. O., Harris, A., Peltier, A., Villeneuve, N., Coppola, D., Gouhier, M. and Drenne, S. (2022) “Volcanic crisis management supported by near real- time lava flow hazard assessment at Piton de la Fournaise, La Réunion”, Volcanica, 5(2), pp. 313–334. doi: 10.30909/vol.05.02.313334. - link

Lanzarote / Timanfaya - photo pano G.Keller / InVolcan - one click to enlarge

Lanzarote / Timanfaya - photo pano G.Keller / InVolcan - one click to enlarge

The Timanfaya lava fields in Lanzarote are "shrinking" an average of 0.6 centimeters per year as they continue to cool, even though three centuries have passed since the eruption that formed them (1730-1736) 

All these phenomena occur in the so-called Islote de Hilario, the point of the park with the greatest thermal anomalies detected, where temperatures of 380°C have been measured just six meters below ground and almost double that, 605° C, about thirteen meters .

Seven researchers from the University of Leeds (UK), the Institute of Natural Products and Agrobiology of Tenerife (IPNA-CSIC) and the Research Center for Geography and Crust Dynamics of Japan, led by Victoria Purcell and Eoin Reddin, publish this month in the journal "Geochemistry, Geophysics, Geosystems" a work that shows what is happening in a larger area of ​​​​the park, about 20 square kilometers.
 

1730-1736 Lanzarote - eruptions in Timanfaya - IGN.es

The Timanfaya eruption is one of the most spectacular known to man in history: it lasted almost six years (2,055 days), from September 1, 1730 to April 16, 1736, covering 200 square kilometers of lava (a quarter of Lanzarote) and emitted between two and five cubic kilometers of material through a crack about 15 kilometers long, leaving behind a landscape dotted with 30 volcanoes.

This team reviewed three decades of satellite measurements of the relative altitude above the Timanfaya lava sea, which reveal that they are contracting due to cooling at a rate of six millimeters per year, which has implications important.

The first, and most obvious, is that after three centuries the lava has not yet completely cooled, at least below the surface, with implications for the study of other eruptions; and the second, and more relevant, suggests that the maximum thickness of the lava layer of Timanfaya is not 60 meters maximum, as had been estimated to date, but between the double and the triple (from 100 to 150 meters)... the eruptions have therefore emitted more volcanic material than calculated so far. .
 

Source: Diario of Lanzarote

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
Nevados de Chillan V.C. - 16.10.2022 / 4:39 p.m. local - webcam Andarivel - Sernageomin OVDAS - one click to enlarge

Nevados de Chillan V.C. - 16.10.2022 / 4:39 p.m. local - webcam Andarivel - Sernageomin OVDAS - one click to enlarge

In Chile, the Sernageomin recorded at the Nevados de Chillan volcanic complex on October 16 at 4:13 p.m. local time an LP earthquake associated with internal fluid dynamics.

An explosion, with a high pyroclast load, was accompanied by a plume higher than 400 meters (but undetermined) dispersing towards the SE. A pyroclastic flow developed on the NNE slope, over 500 meters from the active crater.

The technical alert remains in Amarilla.

 

Source: Sernageomin

Gunung Ibu - 2022.10.17 / 09:06 WIT - PVMBG Magma Indonesia webcam

Gunung Ibu - 2022.10.17 / 09:06 WIT - PVMBG Magma Indonesia webcam

In the Moluccas, the Gunung Ibu activity continues.

The volcano is clearly visible until it is covered by fog 0-III. The plume of gas and ash from the main crater is white and gray with fine, medium to thick intensity, about 200-800 meters from the summit.

The seismicity of October 16 is characterized by:
- 77 eruption earthquakes, with an amplitude of 15 to 30 mm and an earthquake duration of 20 to 70 seconds.
- 5 avalanche earthquakes, with an amplitude of 2 mm and an earthquake duration of 15 to 25 seconds.
- 56 bursts of earthquakes with an amplitude of 5 to 14 mm and an earthquake duration of 10 to 40 seconds.
- 4 times the harmonics, with an amplitude of 2 to 9 mm and an earthquake duration of 45 to 170 seconds.
- 23 shallow volcanic earthquakes, with an amplitude of 3 to 8 mm and an earthquake duration of 4 to 7 seconds.
- 1 deep volcanic earthquake with an amplitude of 20 mm, S-P 2 seconds and an earthquake duration of 8 seconds.
- 5 distant tectonic earthquakes, with an amplitude of 2 to 30 mm, S-P was not observed and the duration of the earthquake was 40 to 130 seconds

Activity is at level 2 / alert.
Recommendation
Communities around Mount Ibu and visitors/tourists should not travel within 2.0 km and the sectoral expansion is 3.5 km towards the crater opening in the northern part of the active crater of Mount Ibu.
In the event of ash rain, people who are active outside the home are advised to use nose, mouth (mask) and eye (goggles) protection.

 

Source: Magma Indonesia

Myrdalsjökull - cauldrons and basin boundary - Recent earthquakes shown in red at Mýrdalsjökull (the glacier that covers the Katla volcano). Blue lines: water/drainage separations; X with numbers, cauldron locations. - doc. K.Jonsdottir 16.10.2022 - one click to enlarge

Myrdalsjökull - cauldrons and basin boundary - Recent earthquakes shown in red at Mýrdalsjökull (the glacier that covers the Katla volcano). Blue lines: water/drainage separations; X with numbers, cauldron locations. - doc. K.Jonsdottir 16.10.2022 - one click to enlarge

On October 16 at 07:54 there was an earthquake of magnitude 3.0 at Mýrdalsjökull (Katla volcano) and others at 12:10 of magnitude 3.0 and 2.8. Since the day before, increased seismic activity has been noticed under the glacier, including an earthquake of M 3.8 at 11:50 p.m.
The earthquakes are all located near sinkholes/cauldrons 10 and 11 in the eastern part of Kötluäskja.

 

Current yellow weather alerts, (a small) jökulhlaup in progress from Grímsvötn and now earthquakes (M3.8, M3.0, M2.8) in Katla, with possible flooding in Múlakvísl ! Please note that one should NOT visit the Kötlujökull / Höfðabrekkujökull glacier caves, and travel near the river and especially at its source, due to gaseous pollution.

 

Sources: IMO via Kristín Jónsdóttir

Myrdalsjökull - date and magnitude of earthquakes on 16.10.2022 / 13:00 - Doc. IMO

Myrdalsjökull - date and magnitude of earthquakes on 16.10.2022 / 13:00 - Doc. IMO

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Sismologia
Alaid - photo S. Lakomov 28.09.2022 / KVERT archives - one click to enlarge

Alaid - photo S. Lakomov 28.09.2022 / KVERT archives - one click to enlarge

Alaid - thermal anomalies on 14.10.2022 / 4:40 p.m. - Doc. Mirova _MODIS_VRP & Volcanic ash advisory on 15.10.2022 / 0600Z - Doc. VAAC Tokyo
Alaid - thermal anomalies on 14.10.2022 / 4:40 p.m. - Doc. Mirova _MODIS_VRP & Volcanic ash advisory on 15.10.2022 / 0600Z - Doc. VAAC Tokyo

Alaid - thermal anomalies on 14.10.2022 / 4:40 p.m. - Doc. Mirova _MODIS_VRP & Volcanic ash advisory on 15.10.2022 / 0600Z - Doc. VAAC Tokyo

Explosive activity increased at Alaid volcano in the northern Kuriles: explosions sent ash up to 5-5.2 km a.s.l., ash plume extends 152 km east of volcano.

Mirova notes thermal anomalies at 1112 MW on 13.10 and 1822 Mw on 14.10.2022

Moderate eruptive activity of the volcano continues. Ash explosions up to 8 km (26,200 ft) above sea level could occur at any time. Ongoing activity could affect international and low-flying aircraft. The aviation color code remains orange.


Sources: KVERT / Himawari-8, VAAC Tokyo, Mirova.

Ebeko - photo © RIA Novosti Alexandre Piragis 28.09.2022 - click to enlarge

Ebeko - photo © RIA Novosti Alexandre Piragis 28.09.2022 - click to enlarge

A moderate eruptive activity continues at Ebeko on October 14, with a plume of gas and ash up to 2.4 km a.s.l., drifting southeast from the volcano.

Ash explosions up to 6 km. asl. could occur at any time and affect aircraft operating at low altitude and the airport of Severo-Kurilsk. The aviation color code remains at orange.

 

Source: KVERT and VAAC Tokyo

Mauna Loa - seismic sequence on 14.10.2022 - Doc. USGS interactive map

Mauna Loa - seismic sequence on 14.10.2022 - Doc. USGS interactive map

Two moderate earthquakes occurred beneath the southern tip of the island of Hawai'i at 9:07 a.m. this morning. The first earthquake (magnitude -4.6) occurred slightly offshore and south of Pāhala, about 13 km (8 mi) deep. It was followed 24 seconds later by a larger 5.0 magnitude earthquake just south of Pāhala, 7.4 km (4.6 mi) below Highway 11. These two larger earthquakes were followed by a series of aftershocks, mostly below magnitude 3.0, but some of the largest down to magnitude -4.0. The aftershock sequence continues, between 0 and 12 km (0 and 7 mi) depth, south of Pāhala. Aftershocks could continue for days or even weeks and be large enough to be felt.
 

This sequence of earthquakes appears to be related to readjustments along the southeast flank of Mauna Loa volcano. There was no immediate effect on the continued unrest below Mauna Loa's summit, which remains elevated at levels similar to last week. On several occasions, large earthquakes have preceded past eruptions of Mauna Loa, although they have generally been larger than today's earthquakes. It is not known at this time if this sequence of earthquakes is directly linked to the ongoing unrest on Mauna Loa.

The volcanic alert is Advisory, and the aviation code Yellow.

 

Sources: HVO and Big island video news.

Merapi - activity report between October 7 and 13, 2022 - Doc. BPPTKG

Merapi - activity report between October 7 and 13, 2022 - Doc. BPPTKG

This week, from October 7 to 13, 2022, 7 lava avalanches were observed at Southwest Merapi, dominant up to the Bebeng River with a maximum slip distance of 1,500 m.

No significant morphological changes were observed from the southwest dome and the central dome. The volume of the dome is fixed, namely for the southwest lava dome of 1,626,000 m³ and the central dome of 2,772,000 m³.

Merapi - seismicity from 07 to 13.10.2022 - Doc. BPPTKG

This week 354 deep volcanic earthquakes (VTA), 1 shallow volcanic earthquake (VTB), 243 multiphase earthquakes (MP), 1 low frequency earthquake (LF), 1 tremor episode, 378 tremors of avalanche land (RF), 39 gusts (DG) and 8 tectonic earthquakes (TT).

Mount Merapi's deformation that was monitored using EDM and GPS this week showed no significant changes.

The activity remains at level 3 / siaga, with unchanged recommendations.

 

Source: BPPTKG

Stromboli - 15.10.2022 / 06:39 - webcam therm Sct0133 / INGV OE

Stromboli - 15.10.2022 / 06:39 - webcam therm Sct0133 / INGV OE

The INGV OE reports that the eruptive scenario at Stromboli seems to be in sharp decline compared to what was observed in the previous days. The projection activity at the level of the N 2 crater (North zone) persists but is much more contained, as well as the thermal anomaly associated with the apical portions of the lava flow which seems to decrease. Field observations report that the lava flows seem to be no longer fed, however this consideration could be affected by the uncertainty due to the progress of the lava flow inside the erosion channel.

The evaluation of the state of the lava flow and the altitude of the lava fronts will be carried out when the marine conditions are attenuated from the boat and by observing the Sciara del Fuoco from the front. The frequency and magnitude of collapses mainly from the lava front decreased, ordinary explosive activity fell to the lowest level.
From the seismic point of view, since the last update, no significant change has been recorded: the average amplitude of the volcanic tremor continues to show small fluctuations in its values ​​and always remains confined to the medium-low level.
The GPS signal from Timpone del Fuoco (STDF) records at 17:20 UTC on 10/13/2022 an impulsive variation of the eastern component of about 1.5 cm. This variation is not visible on the clinometric signals. Other analyzes are in progress for the interpretation of this signal.

 

Note that with the eruptive activity, new mudslides and ash / blocks affect Stromboli
 

Source: INGV communication 14.10.2022 / 6:05 p.m. loc.

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Piton de La Fournaise - the OVPF teams in the field give the scale - photo 30.09.2022 OVPF

Piton de La Fournaise - the OVPF teams in the field give the scale - photo 30.09.2022 OVPF

The eruption started at Piton de La Fournaise on 09/19/2022 around 07:48 local time continues.

The amplitude of the eruptive tremor (indicator of surface lava emission) has been increasing since 9:40 p.m. local time yesterday (5:40 p.m. UTC). This intensification is very certainly linked to an increase in pressure within the eruptive cone which first led to the widening of the opening of the main mouth of the cone then to an increase in activity of the secondary mouth (to the south of the main cone) around 23:15 local time.

Piton de La Fournaise - Evolution of the RSAM (indicator of a surface lava emission) since 09/19/2022 00:00 UTC time (04:00 local time) on the RVA seismological station located at the Rivals crater (© OVPF/IPGP ).

Piton de La Fournaise - Evolution of the RSAM (indicator of a surface lava emission) since 09/19/2022 00:00 UTC time (04:00 local time) on the RVA seismological station located at the Rivals crater (© OVPF/IPGP ).

The images from the OVPF-IPGP webcam located at Piton de Bert show since 11:15 p.m. local time yesterday evening a lava projection activity greater than the previous days at the level of the eruptive site, with an enlargement of the main eruptive mouth and secondary.

Degassing is still observed at the eruptive site

the majority of lava flows are still through lava tunnels within which many resurgences are visible; lava flows also occur directly from the secondary mouth.

The lava flow estimates established by satellite method on the HOTVOLC (OPGC - Clermont Auvergne University) and MIROVA (University of Turin) platforms indicate an average flow over the last 24 hours relatively stable and low around 2-4 m³/s. As lava flow activity now takes place primarily in tunnels, these estimates are minimum values.

A main flow of fluid lava formed and was advancing eastward at about 150 meters per hour yesterday.

Piton de La Fournaise - the eruptive site on 09.30.2022 / 05:45 UT - webcam Piton de Bert 4 / OVPF - one click to enlarge

Piton de La Fournaise - the eruptive site on 09.30.2022 / 05:45 UT - webcam Piton de Bert 4 / OVPF - one click to enlarge

Piton de La Fournaise - For comparison: shooting of the eruptive site on September 28, 2022 around 3 p.m. (local time). The main mouth was more closed and the secondary mouth (on the left in the photo) was already visible but of small size (©OVPF-IPGP).

Piton de La Fournaise - For comparison: shooting of the eruptive site on September 28, 2022 around 3 p.m. (local time). The main mouth was more closed and the secondary mouth (on the left in the photo) was already visible but of small size (©OVPF-IPGP).

The processing by stereophotogrammetry of the images acquired by the OVPF-IPGP teams on September 28, 2022 made it possible to estimate the size of the eruptive cone. It was at this date, at its highest point, about 27 m high and 87 m wide.

A volcano-tectonic earthquake was recorded directly above the summit area over the past 24 hours.

The resumption of slight inflation (swelling) over the entire volcano (summit and enclosure) is confirmed but remains of very low intensity for the moment (< 1 cm).

Alert level: Alert 2-1 (Access to the Enclosure prohibited; eruption in the Enclosure without any particular threat to the safety of persons, property or the environment)

 

Source: OVPF-IPGP

Find all the information relating to the activity of Piton de la Fournaise on the various OVPF-IPGP media: - the website: ipgp.fr/fr/ovpf/actualites-ovpf - the Twitter account: twitter. com/obsfournaise - the Facebook account: facebook.com/ObsVolcanoPitonFournaise

Piton de La Fournaise - 3D reconstruction by stereophotogrammetry of the eruptive cone from images (drone) acquired on September 28, 2022 (©OVPF-IPGP).

Piton de La Fournaise - 3D reconstruction by stereophotogrammetry of the eruptive cone from images (drone) acquired on September 28, 2022 (©OVPF-IPGP).

In Suwanosejima, there were 7 explosions on September 29 and 5 on September 30 until 3:00 p.m. In addition, large volcanic blocks are sometimes observed reaching about 500m from the center of the crater.
The volcanic plume accompanying the eruption rose up to 1,500m above the crater rim and a glowing glow was observed at night.
According to the Fukuoka District/Toshima Village Meteorological Observatory, about 5 km south-southwest of Mitake Crater, rumbling and falling tephra have been confirmed.
At 0036 and 17:51 on September 29, a large volcanic earthquake occurred and an earthquake intensity of 1 was observed with the epicenter on the west side of Suwanosejima.

Minor fluctuations were observed suggesting an increase in magma accumulation.
Volcanic earthquakes on the western side of the island, including large ones, continue to occur.
Vigorous eruptive activity will continue in the future, and a large volcanic eruption will occur within a radius of about 2 km from the center of Mitake Crater, according to the JMA report.

 

Source: JMA – information on the situation of the volcano on September 30, 2022 / 4 p.m. / Fukuoka District Meteorological Observatory/Kagoshima Local Meteorological Observatory.

Suwanosejima - explosion of 09.30.2022 / 17:17-18 - JMA webcam

Suwanosejima - explosion of 09.30.2022 / 17:17-18 - JMA webcam

A minor, passive ash emission from an active vent behind crater lake at Whakaari/White Island observed on Sunday September 18 has not been seen since.

The North Rim web camera continues to produce views of the crater area and regular checks by our National Geohazard Monitoring Center have shown no ash emissions. Observations from the TropOMI satellite which images sulfur dioxide (SO2) once a day have shown no signal from Whakaari/White Island since Sunday 18 September.
In recent days, images from the North Rim camera have become less clear. This is a normal result of the island vapor plume drifting over the camera and depositing a thin, salty film on the camera's protective cover. Images remain bright enough to provide useful views of the active crater area. The thin, salty film will often disappear with the next heavy rain.

Whakaari - activity downing - alert remains at 2 - GeoNet webcam comparative views 18.09.2022 & 28.09.2022 - one click to enlarge

Whakaari - activity downing - alert remains at 2 - GeoNet webcam comparative views 18.09.2022 & 28.09.2022 - one click to enlarge

GeoNet has previously suggested that the minor, passive emission of ash and sulfur dioxide on Sunday September 18 was most likely due to a small, shallow batch of magma releasing its gas and carrying small magma fragments with it. The absence of other ash or sulfur dioxide emissions since confirms this conclusion. There is no evidence of increased activity at Whakaari/White Island.

The VAL remains at Level 2 (Moderate to Intense Disorder), acknowledging the current level of activity, but also continuing to recognize the greatest level of uncertainty in our interpretation due to the current lack of consistent and useful real-time data. The Aviation Color Code is lowered to yellow, reflecting a reduced likelihood of minor ash emissions.

 

Source: GeoNet

Reykjanes ridge - earthquake of 01.10.2022 / 01:18 UTC and regional seismicity - Doc. EMSC automatic location (2)

Reykjanes ridge - earthquake of 01.10.2022 / 01:18 UTC and regional seismicity - Doc. EMSC automatic location (2)

The seismic swarm, which started in the southern part of the Reykjanes Ridge about 4 days ago, continues, with about 80 events recorded between magnitude 4.5 to 5.9.

 

 

Citizen
Response

 

 

 

 

Date & Time 

UTC

Latitude

degrees

Longitude

degrees

Depth

km

Mag

[+]

Region name

[+]

 

 

 

 

 

2022-10-01   04:58:04.21hr 52min ago

53.81 

N  

35.30 

W  

10

4.8

 REYKJANES RIDGE

 

 

 

 

2022-10-01   02:06:09.54hr 44min ago

53.91 

N  

35.28 

W  

10

5.0

 REYKJANES RIDGE

 

 

 

 

2022-10-01   01:18:53.95hr 31min ago

53.75 

N  

35.51 

W  

10

5.9

 REYKJANES RIDGE

 

 

 

 

2022-09-30   19:52:05.510hr 58min ago

53.92 

N  

35.33 

W  

10

4.8

 REYKJANES RIDGE

 

 

 

 

2022-09-30   12:50:09.9

54.07 

N  

35.29 

W  

10

4.8

 REYKJANES RIDGE

 

 

 

 

2022-09-30   12:21:07.3

53.62 

N  

35.18 

W  

10

4.6

 REYKJANES RIDGE

 

 

 

 

2022-09-30   11:38:53.2

53.54 

N  

35.34 

W  

10

4.6

 REYKJANES RIDGE

 

Bold : Earthquakes with a magnitude ≥ 4.5 in Euro-med, or ≥ 5.5 in the world
Red : Earthquakes with a magnitude ≥ 5 in Euro-med, or ≥ 6 in the world

Sources: USGS earthquake hazards program and EMSC

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Sangay - ash emission on 27.09.2022 / 06:53 loc. - cam ECU911 / IGEPN - one click to enlarge

Sangay - ash emission on 27.09.2022 / 06:53 loc. - cam ECU911 / IGEPN - one click to enlarge

Sangay - 27.09.2022 / 6:20 UTC - GOES-16 ABI / NOAA image

Sangay - 27.09.2022 / 6:20 UTC - GOES-16 ABI / NOAA image

From 01:00 TL, September 27, 2022, thanks to satellite images (GOES-16), an ash cloud is observed which reaches about 2 km above the crater of the Sangay volcano, Ecuador, and headed towards the southwest.

Therefore, there is a possibility of ash fall in the province of Chimborazo. This phenomenon has persisted during the current eruptive period which began in May 2019.

The IG-EPN continues to monitor the event and will report in a timely manner if changes in seismic signals are detected.

 

In the past 24 hours, the Washington VAAC has issued 3 reports of ash emissions in a west and northwest direction with a maximum height of 2,400 meters above crater level.
Frequent small columns of ash were observed during the day.
The FIRMS system records 34 thermal alerts and MIROVA records 2 high thermal alerts (239 and 196 MW) in the last 24 hours.
This morning, thanks to the images shared by ECU-911, the volcano was clear, an emission of ash could be observed 800 meters above the summit in a southwesterly direction. At the moment, the volcano is cloudy.
Seismicity is significant, with 825 explosion earthquakes (EXP), 12 Long Period earthquakes (LP), and 22 emission earthquakes (TREMI)
The alert remains at the Amarilla level.

 

Source: IGEPN

Home Reef - volcanic events of 09.27.2022 (red dots), and ash eruption (gray dot) - Doc. VOLCAT via TGS

Home Reef - volcanic events of 09.27.2022 (red dots), and ash eruption (gray dot) - Doc. VOLCAT via TGS

In the Pacific, the geological service of the Tonga Islands reports for September 27, 2022 a total of 21 volcanic events at Home Reef, including an ash eruption at 12:36 p.m., imaged by the Himawari-8 satellite.

No new measurements from the new island since September 19: 211 m. x 218m. Surface: 8.6 acres / 34800 m², estimated height: 15 m. asl.

Notice for the navy: do not enter waters within a radius of 4 km. around Home Reef

 

Source: Tonga Geological Services

Piton de La Fournaise - shooting of the eruptive site on September 27, 2022 at 1:55 p.m. local time. On the left the cone in formation since the beginning of the eruption on September 19, on the right the peak Kalla Pélé (eruption August-October 2015) (©OVPF-IPGP) - one click to enlarge

Piton de La Fournaise - shooting of the eruptive site on September 27, 2022 at 1:55 p.m. local time. On the left the cone in formation since the beginning of the eruption on September 19, on the right the peak Kalla Pélé (eruption August-October 2015) (©OVPF-IPGP) - one click to enlarge

The amplitude of the eruptive tremor (indicator of surface lava emission) at Piton de La Fournaise has remained generally stable over the past 24 hours, at around 20% of its initial amplitude.

No volcano-tectonic earthquake has been recorded directly above the summit area over the past 24 hours.

Piton de La Fournaise - The amplitude of the eruptive tremor (indicator of surface lava emission) to station  has remained generally stable over the past 24 hours / as of 27.09.2022 (©OVPF-IPGP)

Piton de La Fournaise - The amplitude of the eruptive tremor (indicator of surface lava emission) to station has remained generally stable over the past 24 hours / as of 27.09.2022 (©OVPF-IPGP)

A slight inflation (swelling) of the summit zone of the volcano seems to be emerging, this parameter will be confirmed in the coming days.

The lava flow estimates established by satellite method on the HOTVOLC (OPGC - Clermont Auvergne University) and MIROVA (University of Turin) platforms indicate an average flow over the last 24 hours that is relatively stable and low around 2 m3/s, with a maximum peak rated at 7 m3/s.

The observations of the OVPF-IPGP teams in the field show for today an activity similar to the previous days.

Alert level: Alert 2-1 (Access to the Enclosure prohibited; eruption in the Enclosure without any particular threat to the safety of persons, property or the environment)

 

Source: OVPF-IPGP

Find all the information relating to the activity of Piton de la Fournaise on the various OVPF-IPGP media: - the website: ipgp.fr/fr/ovpf/actualites-ovpf - the Twitter account: twitter. com/obsfournaise - the Facebook account: facebook.com/ObsVolcanoPitonFournaise

Vulcano - INGV photo archives

Vulcano - INGV photo archives

At Vulcano, in the Aeolian Islands, temperatures remain stable at high values ​​along the upper edge of the crater.
The CO2 flux in the crater area remains stable at medium-high values.
The SO2 flux in the crater area is stable at a moderately medium-high level
Geochemistry of fumarolic gases: The concentration of magmatic species (CO2, He, N2) is slightly decreasing (11 mol% CO2 on 09/14/2022).
The CO2 flux at the base of the La Fossa cone and in the Vulcano Porto area: stable CO2 flux values ​​above the background noise in the Rimessa site; stable but still abnormal values ​​on the Camping Sicilia site; slightly decreasing values ​​at the Palizzi site (P4max); in the Faraglione site the values ​​recorded are stable and close to the baseline values
Monthly CO2 Flux Campaign: C emissions in the Vulcano Porto area show no significant change from the previous month and still remain at levels above background.

Vulcano - spatial distribution of CO2 flux from the ground on 20.09.2022 - Doc. INGV OE

Vulcano - spatial distribution of CO2 flux from the ground on 20.09.2022 - Doc. INGV OE

The INGV reports a stabilization of the supply of fluids of fumarolic origin to the thermal aquifer is generally observed, but still remains at abnormal levels in certain sites.

The other parameters do not show significant variations.

 

Source: INGV OE – full text https://buff.ly/3LPH6Zo

Reykjanes Ridge - seismic swarm and its location: A seismic swarm takes place south of the Reykjanes Ridge, in the Atlantic at the Charlie-Gibbs transform fault, and reveals a possible magmatic intrusion. Source: USGS Earthquake Hazards, via @EQuake_Analysis - one click to enlargeReykjanes Ridge - seismic swarm and its location: A seismic swarm takes place south of the Reykjanes Ridge, in the Atlantic at the Charlie-Gibbs transform fault, and reveals a possible magmatic intrusion. Source: USGS Earthquake Hazards, via @EQuake_Analysis - one click to enlarge

Reykjanes Ridge - seismic swarm and its location: A seismic swarm takes place south of the Reykjanes Ridge, in the Atlantic at the Charlie-Gibbs transform fault, and reveals a possible magmatic intrusion. Source: USGS Earthquake Hazards, via @EQuake_Analysis - one click to enlarge

A seismic swarm takes place south of the Reykjanes Ridge, in the Atlantic at the level of the Charlie-Gibbs transform fault, and reveals a possible magmatic intrusion.

 

Source: USGS Earthquake Hazards

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At the Piton de la Fournaise, after almost 3 days of decrease, the amplitude of the eruptive tremor (indicator of a lava emission on the surface) gradually re-engaged during last night. Its level stabilized during the day at around 20% of its initial amplitude.

Seismicity under the summit area remains very low with 1 single volcano-tectonic earthquake recorded over the last 24 hours.

Piton de la Fournaise - Evolution of the RSAM (indicator of a lava emission on the surface) since 19.09.2022 / 00h00 UTC time (04:00 local time) at 22.09.2022- Doc. OVPF

Piton de la Fournaise - Evolution of the RSAM (indicator of a lava emission on the surface) since 19.09.2022 / 00h00 UTC time (04:00 local time) at 22.09.2022- Doc. OVPF

Piton de la Fournaise - During a thinning - OVPF photo

Piton de la Fournaise - During a thinning - OVPF photo

Thanks to an improvement in weather conditions for a few hours yesterday afternoon, a team from the observatory was able to go to the eruptive site with the support of the Air Force Section of the Gendarmerie and the Gendarmerie Platoon of Haute Mountain. This intervention allowed:
- to confirm the precise location of the eruptive vent: A main mouth animated by a lava fountain about 20 m high, in the central part of the crack, and two more modest mouths are active. A small cone leans against the Kalla Pélé piton.
- to take a sample of lava in the flow near the vent,
- to take a sample of older projections,
- to evaluate the lava flow at about 3 m³/s.

Estimates of lava flow were established by satellite method on the HOTVOLC platform (OPGC - Clermont Auvergne University), during yesterday afternoon (peaks at 2.5 m³ / sec), as well as this morning at the favor of short thinnings (peak at 3.6 m³/s).

At the end of the day yesterday, the images from the OVPF-IPGP webcams showed a very marked decrease in activity focused on the lowest part of the crack system which opened on Monday.

Due to the very bad weather conditions on the Fournaise massif on 22.09, no on-site reconnaissance could be carried out by the OVPF-IPGP teams, whether on foot or by air. Overcast weather continues today.

 

Alert level: Alert 2-1 (eruption in the Enclosure without any particular threat to the safety of people, property or the environment)

 

Source: OVPF

Find all the information relating to the activity of Piton de la Fournaise on the various OVPF-IPGP media: - the website: ipgp.fr/fr/ovpf/actualites-ovpf - the Twitter account: twitter. com/obsfournaise - the Facebook account: facebook.com/ObsVolcanoPitonFournaise

Sheveluch - 23.09.2022 / 07:41 - IVS webcam

Sheveluch - 23.09.2022 / 07:41 - IVS webcam

Sheveluch - volcanic re-suspended ash advisory at 23.09.2022 / 0600Z - Doc. VAAC Tokyo

Sheveluch - volcanic re-suspended ash advisory at 23.09.2022 / 0600Z - Doc. VAAC Tokyo

The growth of the Sheveluch lava dome continues; strong fumarolic activity, incandescence of the lava dome, explosions and hot avalanches accompany this process. Video and satellite data by Kvert showed a thermal anomaly over the volcano.

The resuspended ash plume extended 430 km east of the volcano.

 

Source: KVERT and VAAC Tokyo

Tectonic context of Samoa and Ta'u island - image Sentinel-2 Copernicus / GVP-12401
Tectonic context of Samoa and Ta'u island - image Sentinel-2 Copernicus / GVP-12401

Tectonic context of Samoa and Ta'u island - image Sentinel-2 Copernicus / GVP-12401

The Taʻū island related earthquake swarm continues, with seismicity remaining weak over the past week. The position of the source of the earthquake has not changed. Three earthquakes were reported in the past week, with magnitudes similar to larger earthquakes earlier in this swarm. Satellite data from the previous week observed no volcanic activity.

The National Earthquake Information Center (NEIC) will soon begin publishing the preliminary locations of the largest earthquakes that occurred during this period of seismic unrest in American Samoa. Earthquake locations and depths are currently best estimates, with large uncertainties resulting from the fact that the monitoring network is limited to the east-west orientation of the islands of American Samoa.

Current volcanic alert level: Advisory
Current Aviation Color Code: Yellow

 

Source: USGS/HANS

Tjörnes Fracture Zone - location and magnitude of earthquakes as of 23.09.2022. / 07:55 - Doc. IMO
Tjörnes Fracture Zone - location and magnitude of earthquakes as of 23.09.2022. / 07:55 - Doc. IMO
Tjörnes Fracture Zone - location and magnitude of earthquakes as of 23.09.2022. / 07:55 - Doc. IMO

Tjörnes Fracture Zone - location and magnitude of earthquakes as of 23.09.2022. / 07:55 - Doc. IMO

The seismic swarm over the Tjörnes Fracture Zone, which began on September 8, continues to decline.

More than 12 thousand earthquakes have been detected since the start of the swarm. When the swarm intensity was at its highest, a thousand earthquakes were detected each day, but the past two days several hundred earthquakes have been recorded per day.

The Ministry of Civil Protection and Emergency Management announced a level of uncertainty for ongoing seismic activity in North Iceland on September 9, 2022.


Source: IMO, written by a specialist as of 21 Sep 09:35 GMT

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The Home Reef submarine volcano in the central Tonga Islands re-emerged above sea level on Saturday, September 10, 2022.

The detection was first made by VOLCAT on September 10 at 01:39, and confirmed by Sentinel-2 images at 12:29.

The eruption is fumarolic, and releases gases more than a kilometer high; no volcanic ash is detected.

Home Reef submarine volcano eruption &t& first detected by VOLCAT on 10.09.2022 / 01:39 - Doc. Tonga Geological Services - one click to enlarge

Home Reef submarine volcano eruption &t& first detected by VOLCAT on 10.09.2022 / 01:39 - Doc. Tonga Geological Services - one click to enlarge

Home Reef - image Sentinel-2 L2A highlight optimized natural color from 10.09.2022 / 1:59 p.m. - Doc. Copernicus / via Tonga Geological Services - one click to enlarge

Home Reef - image Sentinel-2 L2A highlight optimized natural color from 10.09.2022 / 1:59 p.m. - Doc. Copernicus / via Tonga Geological Services - one click to enlarge

Home Reef is located 25 km away. southwest of Late island, and 22 km. northeast of Lateiki.

Its re-emergence forms an area of ​​approximately 1 acre / 4056 m², with a diameter of 70 meters and an estimated elevation of 10 m. above sea level.

Last eruption in 2006.

The danger is for maritime navigation, which must remain 3 km away. from Home Reef.

 

Source: Tonga Geological Services, Government of Tonga.

3D bathymetric model of the island arc of the Tonga Archipelago, with known volcanic eruptions since 2000 - Brandl Philipp - one click to enlarge

3D bathymetric model of the island arc of the Tonga Archipelago, with known volcanic eruptions since 2000 - Brandl Philipp - one click to enlarge

The sequence of earthquakes beneath the central part of Lake Taupō (Taupō-nui-a-Tia), New Zealand, continues at a rate of about 40 to 50 earthquakes per week. Since the start of the sequence in May 2022, the pace has increased from 30 events per week to more than 40 per week. We have now located more than 650 earthquakes less than 30 km deep.

The M 4.2 earthquake on Saturday morning September 10 is the biggest event this year in Taupō. It was reported felt by 1242 people. The next two largest earthquakes were both magnitude 3.6; the first was recorded on May 17 and the other on July 11, 2022. Since 2000 we have located 7 earthquakes greater than magnitude 4 below the lake, the largest was a M 5.0 on September 4, 2019 located near Motutaiko Island. Saturday's earthquake was 8 km northeast of this 2019 quake.

Earthquakes located by GeoNet in the Lake Taupō region from January 1 to September 12, 2022. All earthquakes presented here were located less than 30 km deep. There are over 650 earthquakes shown on the map - Doc. GeoNet

Earthquakes located by GeoNet in the Lake Taupō region from January 1 to September 12, 2022. All earthquakes presented here were located less than 30 km deep. There are over 650 earthquakes shown on the map - Doc. GeoNet

Earthquakes detected and located in the dotted area delineated on the map every year since 2000. The sequence of earthquakes of 2022 stands out, at this point the numbers exceed the sequences of 2009, are almost equal to those of 2008 and remain lower than those of 2019. - Doc. GeoNet - one click to enlarge

Earthquakes detected and located in the dotted area delineated on the map every year since 2000. The sequence of earthquakes of 2022 stands out, at this point the numbers exceed the sequences of 2009, are almost equal to those of 2008 and remain lower than those of 2019. - Doc. GeoNet - one click to enlarge

In addition to seismic activity, GeoNet continuously monitors ground deformation around Taupō. Following the 12 mm uplift observed from lake leveling data, deformation data from GNSS (GPS) instruments around the lake also show a signal indicating horizontal deformation. Numerical modeling indicates that the horizontal extension is consistent with a source of deformation in the main region of seismic activity.

The Taupō Volcanic Center is part of the Taupō Volcanic Zone, a tectonically highly active region with numerous known faults and active volcanism. Activity in this region is often linked to a mix of regional deformation processes and the separate magmatic systems beneath the volcanoes, which has helped inform our view that Volcanic Alert Level 0 is currently appropriate for the volcanic center of Taupō, and remains at level 0.

 

Source: GeoNet – 14.09.2022

Stromboli - S2 mouth ash explosion - INGV OE on 13.09.2022. - one click to enlarge

Stromboli - S2 mouth ash explosion - INGV OE on 13.09.2022. - one click to enlarge

During the week of September 5-11, normal Strombolian-type explosive activity was observed at Stromboli. The total hourly frequency of explosions varied on low values, from 3-5 events/h. The intensity of the explosions was low and medium in both the North Crater area and the Center-South Crater area.
Weak and infrequent (sometimes simultaneously) ash emissions were observed from at least 2 vents located near the S2 crater, sometimes associated with little coarse material.


The seismological parameters monitored do not show any significant variations.
The soil deformation monitoring networks in operation on the island did not show any significant variations during the period studied.
The flow of SO2 at an average and increasing level; the flux of CO2 from the soils in the summit zone is on average values.
The C/S ratio in the plume settles on average values ​​(9.5)
Isotope ratio of dissolved He in heat sinks: there is no update from the July 27, 2022 sampling.
Thermal activity observed by satellite in the summit area was weak.

 

Source : INGV OE  - put online on 13.09.2022

Map of the seabed of the epicenter of the earthquake in Grímsey - earthquakes reviewed by IMO in black and in black and earthquakes 2020-2022 in gray - Doc. via Jarðvísindastofnun Háskólans / 13.09.2022

Map of the seabed of the epicenter of the earthquake in Grímsey - earthquakes reviewed by IMO in black and in black and earthquakes 2020-2022 in gray - Doc. via Jarðvísindastofnun Háskólans / 13.09.2022

More than 8250 earthquakes have been detected since the start of activity in Grímsey. The largest earthquake detected was an M4.9 on September 8 at 04:00. The largest earthquakes were widely felt in northern Iceland. The last major seismic swarm in this area dates back to February 2018.

A seabed map of the earthquake's epicenter in Grímsey has just been uploaded The map shows recent earthquakes according to the IMO seismic table in black and 2020-2022 earthquakes in gray , drawn according to their size. The northernmost part of the ridge north of Grímsey originates at Nafirnar. In this volcanic area, you can see mountains and lava formed after the ice age. The Grímsey earthquake started on the south side of Nafnar, then moved southeast along a broad north-trending sag at Skjálfandadjupi, then back to Nafnar.

The Department of Civil Protection and Emergency Management announced a level of uncertainty for ongoing seismic activity in North Iceland on September 9, 2022.

Source: IMO 13.09.2022 / 15:17 GMT & Jarðvísindastofnun Háskólans

Tjörnes FZ - location and magnitude of earthquakes as of 09.13.2022 / 3:45 p.m. - Doc. IMO
Tjörnes FZ - location and magnitude of earthquakes as of 09.13.2022 / 3:45 p.m. - Doc. IMO
Tjörnes FZ - location and magnitude of earthquakes as of 09.13.2022 / 3:45 p.m. - Doc. IMO

Tjörnes FZ - location and magnitude of earthquakes as of 09.13.2022 / 3:45 p.m. - Doc. IMO

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