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Earth of fire

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

volcanic activity

Publié le par Bernard Duyck
Publié dans : #volcanic activity
 Etna SEC - srombolian activity and ash emissions from 18-19.05.2020 - photo INGVvulcani

Etna SEC - srombolian activity and ash emissions from 18-19.05.2020 - photo INGVvulcani

The Instituto Nazionale di Geofisica e Vulcanologia, Osservatorio Etneo, reports that Strombolian activity was recorded by surveillance networks at 12:12 local time (10:12 UTC) at the saddle cone located between the old and the new cone of the Crater of South-East of Etna
Strombolian activity began to increase from 08:45 UTC in the New Southeast crater, and is accompanied by a modest emission of volcanic ash, which is blown by the wind towards the northeast.
From a seismic point of view, since 09:20 UTC, the amplitude of the volcanic tremors has shown an increase in high values. The source of the volcanic tremor is located near the new southeast crater about 2,900 m above sea level. The infrasonic activity also showed a slight increase, with events being located at the new southeast crater.
The deformation on the ground shows no significant impulsive variation associated with continuous activity. However, a trend of northward movement at the Pizzi Deneri and Northeast crater stations initiated in early May continues.

 

Source: INGVvulcani

Etna SEC - Strombolian activity from 18 and 19 May 2020 - Cam.therm EMOT / INGV OE - one click to enlargeEtna SEC - Strombolian activity from 18 and 19 May 2020 - Cam.therm EMOT / INGV OE - one click to enlarge

Etna SEC - Strombolian activity from 18 and 19 May 2020 - Cam.therm EMOT / INGV OE - one click to enlarge

Etna - trémor on 20.05.2020 - Doc. INGV OE

Etna - trémor on 20.05.2020 - Doc. INGV OE

During the week of May 11 to 17, 2020, the eruptive activity of the Sabancaya volcano remained at moderate levels, with the recording of an average of 12 daily explosions, accompanied by plumes of ash and gas reaching 2, 5 km high above the summit of the volcano, dispersing in an east and southeast sector. Consequently, for the following days, no significant change is expected regarding its activity.

The IGP recorded and analyzed the occurrence of approximately 413 earthquakes of volcanic origin, associated with the circulation of fluids (magma, gas, etc.) inside the volcano.

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

Satellite surveillance identified the presence of 7 thermal anomalies with values ​​between 1 MW and 10 MW, associated with the presence of a body of lava on the surface of the volcano crater.

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

 

Source: I.G. Peru

Sabancaya - summary of the activity for the week of 11 to 17 May 2020 - Doc. I.G.Peru

Sabancaya - summary of the activity for the week of 11 to 17 May 2020 - Doc. I.G.Peru

Volcanic earthquakes with epicenter near Yugama crater of Kusatsu-Shirane, on the Japanese island of Honshu, have been increasing for weeks.

According to the JMA, volcanic activity is increasing on Mount Shirane, with the possibility of an eruption which could affect an area of ​​about 1 km near the active crater Yugama.

 

Source: JMA Information on the state of the Kusatsu-Shirane volcano N ° 49.

Mt.Kusatsu-Shirane - photo Ski Mania

Mt.Kusatsu-Shirane - photo Ski Mania

 In Poas, no surface rash is reported.

The heavy rains of May 17 raised the level of the acid lake, where we observe a degassing of mouths A and B.

The seismometers detected on the evening of May 18 a tremor which faded this morning. On 19 may, a frequent record of low-frequency (LP) and low-amplitude volcanic earthquakes is maintained. Low amplitude tremors are variable in amplitude and occur between continuous and banded tremors.

Except for a peak in CO2 / SO2 on May 17, this ratio is still around 1.

 

Source: Ovsicori

Poas - 19.05.2020 / 7.20am - Ovsicori webcam

Poas - 19.05.2020 / 7.20am - Ovsicori webcam

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
 Semeru - hot spot at the top and on the lava flow on 05.15.2020 Sentinel-2 L1C image bands 12,11,4 - one click to enlarge

 Semeru - hot spot at the top and on the lava flow on 05.15.2020 Sentinel-2 L1C image bands 12,11,4 - one click to enlarge

The Semeru Volcano Observatory issued an orange VONA on May 16, 2020 at 2:49 UTC / 9:49 local time, following an eruption with ash cloud at about 4,000 meters, and perhaps more, due to poor observation conditions ((observer at ground) The ashes move west.

The eruption and the ash cloud are confirmed by the VAAC Darwin, which specifies that the eruption continues, with a notice of ash dispersion this May 16 at flight altitudes 460 moving east and alt. of flight 200, moving to the southwest. For the VAAC Darwin, the aviation code is red. On May 17, the ash plume was reported at flight altitude 140, and a hot spot was evident at the top.

At the seismicity level, the PVMBG reports for May 16:

- 51 eruption earthquakes, with an amplitude of 10-20 mm, and the duration of the earthquake 47-120 seconds.

- 5 earthquakes of collapse, with an amplitude of 3-8 mm and an earthquake duration of 45-85 seconds. The sliding distance and the direction of fall are not observed.

- 22 blast earthquakes, with an amplitude of 2 to 9 mm and an earthquake duration of 40 to 110 seconds.

- An episode of harmonic tremor, with an amplitude of 3 mm and an earthquake duration of 90 seconds.

 

Sources: Semeru Volcano Observatory / PVMBG, Magma indonesia and VAAC Darwin

Rincon de La Vieja - hydrothermal eruption of 15.05.2020 / 11.28 am - Screan Ovsicori video

Rincon de La Vieja - hydrothermal eruption of 15.05.2020 / 11.28 am - Screan Ovsicori video

At Rincon de La Vieja, the Ovsicori reports a hydrothermal eruption on May 15, 2020 at 11:27 a.m. local, accompanied by a plume of 600 meters (?) Above the crater, and lasting 1 minute.

The cloudiness prevented an accurate estimate of the height of the plume ... observers north of the volcano report a height of 1,000 meters for the vapor and gas plume, and a column of gray sediment 400 meters above the crater.

 

Source: Ovsicori and local observers.

Etna - 16.05.2020 / 02h02 - saddle cone / SEC - Therm. webcam  INGV EMOT

Etna - 16.05.2020 / 02h02 - saddle cone / SEC - Therm. webcam INGV EMOT

From 00.45 hours UTC on May 16, 2020, the surveillance cameras revealed an explosive strombolian activity in the New Crater of SE of Etna, with regard to the mouth called the "saddle". This activity quickly intensified, producing a modest cloud of ash that the winds dispersed at high altitude to the north.
From the seismic point of view, there is no significant variation in the recorded signals. The source of the volcanic tremor is located at the new SE crater, at a depth of about 2900 m above sea level.

From 6:45 h UTC, the strombolian activity at the NCSE, reported in the previous press release (n. 48) ceased.

The explosive activity remains at the Voragine crater, although it has decreased in intensity and frequency, according to the location by INGV staff on May 15.

From the seismic point of view, the signals recorded over the past few hours show conditions of substantial stability compared to the table appearing in the previous press release, without any significant variation compared to average levels.

 

Source: INGVvulcani

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Publié le par Bernard Duyck
Publié dans : #volcanic activity

Two rocky pinnacles in the North Pacific, 1,100 km northwest of Honolulu, the Gardner Pinnacles, are in fact the tip of a huge shield volcano, called Pūhāhonu, meaning "the turtle rising to the surface to breathe ".

Gardner Pinnacles, guano covered rocks - photo Andy Collins, NOAA Northwestern Hawaiian Islands Coral Reef Ecosystem Reserve

Gardner Pinnacles, guano covered rocks - photo Andy Collins, NOAA Northwestern Hawaiian Islands Coral Reef Ecosystem Reserve

He competes at MaunaLoa, on Big Island, for the title of the largest shield volcano in the world.

Impressive in size, because its base is 4,500 meters below the ocean surface, its mass is even more so: according to a sonar analysis made in 2004, its total volume would be 150,000 km³, causing the subsidence of the crust which supports.

New bathymetric and gravimetric maps, refined volume calculations and petrological analyzes show that the Hawaiian volcano Pūhāhonu, dated from 12.5 to 14.1 Ma, located in the northwest of the Hawaiian ridge (NWHR) has twice the size of the Mauna Loa volcano.

Location of Pūhāhonu in relation to Big Island

Location of Pūhāhonu in relation to Big Island

 Bathymetry of the Pūhāhonu volcano - Doc. Direct Science

Bathymetry of the Pūhāhonu volcano - Doc. Direct Science

Its gigantic size would be due to a warmer mantle, particularly a solitary wave in the Hawaiian mantle plume, capable of supplying large volumes of magma, consistent with the compositions of highly forsteritic olivine phenocrysts (more than 91.8% of forsterite, a magnesium silicate) and the high percentage of fusion (24% according to calculations).

 

Source: Earth and Planetary Science letters - Pūhāhonu: Earth's biggest and hottest shield volcano - M.O. Garcia & al.

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Publié le par Bernard Duyck
Publié dans : #volcanic activity

In Costa Rica, the acidic lake of Poas remained hidden on May 14 most of the day, except in the early morning.

The Ovsicori reports stable CO2 / SO2 and H2S / SO2 ratios, around 1.0 and 0.1, respectively.

On the morning of May 14, an SO2 peak of 29.2 ppm was recorded. On the other hand, from the point of view, maximum concentrations of SO2 greater than 2 ppm were detected. Band tremor is observed in the range of 1 to 5 Hz. The lowest frequency tends to be persistent, unlike the highest frequency.

 Poas - degassing at the acid lake on 05.15.2020 / 06:17 am - Ovsicori webcam

Poas - degassing at the acid lake on 05.15.2020 / 06:17 am - Ovsicori webcam

Poas - degassing at the acid lake on 05.15.2020 / 07.20 am - Ovsicori webcam

Poas - degassing at the acid lake on 05.15.2020 / 07.20 am - Ovsicori webcam

At Rincon de La Vieja, a tremor in bands from 0.6 to 5 Hz is observed, but with a more continuous pattern at 9:00 p.m. (UTM + 6) yesterday.

Two eruptions occurred this morning at 5:24 a.m. and 7:04 a.m. (UTM + 6). In both cases, the column rose to about 500 meters above the height of the crater, a total of 2416 m above sea level. No ash fall or lahars are reported.

 

Source: Ovsicori

 Anak Krakatau - hot spot and lava flow from the previous activity - Sentinel-2 L1C bands 12,11,4 du 14.05.2020 - one click to enlarge

 Anak Krakatau - hot spot and lava flow from the previous activity - Sentinel-2 L1C bands 12,11,4 du 14.05.2020 - one click to enlarge

At Anak Krakatau, the volcano seems calm at the seismicity level, with this May 14, two low frequency earthquakes, with an amplitude of 2-3 mm and an earthquake duration of 3-4 seconds, and four episode of continuous tremor with an amplitude of 0.5-3 mm, dominating 1 mm.

Mirova reports thermal anomalies from VRP 12 to 21 MW on May 14, 2020.

A clear satellite image by Sentinel-2 shows the extent of the lava flow generated by the previous period of activity.

 

Sources: PVMBG, Magma Indonesia, Mirova and Sentinel-2

 Anak Krakatau - Radiation power at 05/14.2020 / 6.45 p.m. - Doc. Mirova_MODIS_VRP

 Anak Krakatau - Radiation power at 05/14.2020 / 6.45 p.m. - Doc. Mirova_MODIS_VRP

As an atractive introduction, here is the trailer for the film of the last expedition of the Volcanological Society of Geneva in the crater of Nyiragongo in February 2020. - Link to video

 

Source: Thanks to Patrick Marcel for sharing.

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
Semeru - 12.05.2020 - Landsat 8 image - one click to enlarge

Semeru - 12.05.2020 - Landsat 8 image - one click to enlarge

The seismicity of Semeru, on Java, still on alert 2 / waspada, remains significant.

The PVMBG reports for this May 13 :

- 46 eruption earthquakes with an amplitude between 10 and 22 mm, and lasting from 55 to 210 seconds,

- 17 blast earthquakes with an amplitude of 2-8 mm and a duration of 40-107 sec.

The VAAC Darwin reports a continuation of the explosive activity and mentions a plume reaching an altitude of 4,000 meters, drifting north.

 

Sources: PVMBG, Magma Indonesia and VAAC Darwin.

Semeru - seismicity on 13.05.2020 - Doc. Magma Indonesia

Semeru - seismicity on 13.05.2020 - Doc. Magma Indonesia

In the Philippines, the Phivolcs issued a vigilance notice on May 13 for the Mayon, due to the risk of lahars.

Prolonged and abundant precipitation caused by tropical storm Ambo is likely to generate post-eruption lahars in the main drainages, in particular the Miisi, Binaan, Anoling, Quirangay, Maninila, Masarawag, Muladbucad, Nasisi, Mabinit, Matan-ag and the canals of Basud. In question, the remobilization of the materials deposited by the pyroclastic density currents and the ashes of the eruption from January to March 2018.

Note that the Mayon is still on alert level 2 / moderate level of instability. The volcano emits white plumes of vapor, and has a weak night glow. Inflation of the middle to high part of the volcano, started in late 2019, continues today.

 

Source: Phivolcs.

News from Semeru, Mayon, La Soufrière from Guadeloupe and Etna.

In the Caribbean, we have witnessed since the beginning of 2018 a cyclical process of injecting deep magmatic gases at the base of the hydrothermal system of the Soufrière of Guadeloupe, at a depth between 2 and 3 km below the summit.

It generates a recurrent process of overheating and overpressure of the hydrothermal system which results in disturbances in the circulation of hydrothermal fluids; the evolution of the activity of fumaroles at the summit, as evidenced by the projection of hot, acid mud over a few meters; increased swarm volcanic seismicity; some volcanic earthquakes felt, four between February and April 2018, including an earthquake of magnitude M4.1 on April 27, 2018, the strongest since 1976, deformations of small amplitude and limited to the dome of La Soufrière of the order of 3- 7 mm / year and the continued opening of summit fractures, the fluctuation of the flow rates of fumarolic gas from a pressurized hydrothermal reservoir, an increase in thermal anomalies in the soil at the top of La Soufrière.

These phenomena are not yet clearly associated with an anomaly in the other monitoring parameters which could indicate a possible rise in magma. The latter would typically, but not systematically, manifest itself through numerous deep or felt earthquakes, large-scale deformations beyond the dome, and the emission of sulfur gases at high temperature (> 150 ° C).

 

Source: Volcanological and Seismological Observatory of Guadeloupe (OVSG)

La Soufrière in La Guadeloupe - photo France.fr

La Soufrière in La Guadeloupe - photo France.fr

Etna and cycling

Originally scheduled for the fifth stage of the Giro d'Italia on May 13, 2020, this stage from Enna to Etna (Piano Provenzana), like the race, were postponed because of the pandemic.

The Etnean stage should be run on October 7, with a completely different weather.

For volcanophiles-cyclists, the list and history of Etna winners in Cycling News - .

https://www.cyclingnews.com/features/volcanic-interruption-mount-etna-and-the-giro-ditalia/

News from Semeru, Mayon, La Soufrière from Guadeloupe and Etna.

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Publié le par Bernard Duyck
Publié dans : #volcanic activity

Little to know today ...

Over the past 24 hours, Cenapred has counted 130 exhalations at Popocatépetl, accompanied by volcanic gases and sometimes small amounts of ash. In addition, 172 minutes of tremors and four minor explosions were recorded, two recorded on May 11 at 5:23 p.m. and 11:51 p.m., the others on May 12 at 3:02 a.m. and 6:04 a.m., not observable due to the cloudiness of the area.

During the night, there was no visibility towards the crater due to the weather conditions.

Since the morning, the volcano was observed with a continuous emission of water vapor and gas, however, at the time of this report, due to the cloudy conditions, there is no visibility towards the crater, no emission water vapor, gas and ash will disperse in a northeast direction.

 

Sources: Cenapred & webcamsdeMexico

Popocatépetl seen from San Nicolás de los Ranchos - 12.05.2020 / 08h42 - WebcamsdeMexico

Popocatépetl seen from San Nicolás de los Ranchos - 12.05.2020 / 08h42 - WebcamsdeMexico

In Chile, the Nevados de Chillan complex, after a volcano-tectonic earthquake on May 11 at 8:06 a.m., in connection with rock fracturing, presented some explosions on May 12 at 11:35 a.m., 1:45 p.m. and 2:25 p.m. They were accompanied by plumes of gas and ash at 1,100 meters, 1,600 meters and 1,280 meters above the active crater respectively. The plumes dispersed to the northeast.

The technical alert level remains at Amarilla.

 

Source: Sernageomin- OVDAS

Nevados de Chillan - explosion of 12.05.2020 / 11.35 am - Sernageomin webcam Portezuelo

Nevados de Chillan - explosion of 12.05.2020 / 11.35 am - Sernageomin webcam Portezuelo

At Etna, strombolian activity continues at the "cone of the saddle" of the southeast crater, as well as that of Voragine, all more calmly this May 12.

Etna SEC - strombolian activity, during the night of 11 to 12.05.2020, view of Tremestieri Etneo - photo Boris Behncke

Etna SEC - strombolian activity, during the night of 11 to 12.05.2020, view of Tremestieri Etneo - photo Boris Behncke

An article on INGVvulcani, by Nicola Genzano, Francesco Marchese and Marco Neri, recalls the interest of observation satellites for the study of volcanic activity.

Etna - Thermal anomalies associated with summit volcanic activity - Sentinel-2 L1C image du12.05.2020 bands 12,11,4 - One click to enlarge

Etna - Thermal anomalies associated with summit volcanic activity - Sentinel-2 L1C image du12.05.2020 bands 12,11,4 - One click to enlarge

Etna - map of active craters to facilitate identification on the Sentinel image above - Doc. INGV OE / report of 10.05.2020

Etna - map of active craters to facilitate identification on the Sentinel image above - Doc. INGV OE / report of 10.05.2020

 "... Sentinel 2A / 2B satellites via the MSI (MultiSpectral Instrument) sensor which provides optical band data with high spatial resolution (up to 20 m in infrared bands), play a key role in the study of volcanic activity. At the same time, computer platforms are being developed, capable of guaranteeing simple, systematic and continuous access to these large amounts of data, also allowing cloud computing solutions, ie - say a kind of data processing carried out directly on the Internet, to facilitate the use of these tools in an operational and free manner.

Systems capable of "intercepting" a high availability of data and resources and transforming them into "information" usable by all users represent an added value and a unique opportunity in the context of monitoring volcanic activity, also in support of traditional surveillance systems.

 

In this context, the NHI (Normalized Hotpsot Index) application has just been proposed, based on an original algorithm recently published in the international magazine Remote Sensing (Marchese et al., 2019). This app takes advantage of the density of archives and the high computing capacities offered by Google Earth Engine to analyze and map volcanic thermal anomalies on a global scale, integrating Sentinel 2 and Landsat 8 satellite data (from the American mission NASA / USGS ), with great precision and reduced processing times. The simple graphical interface also guarantees user-friendly use of the application, which can be used both by experts in the sector and by simple enthusiasts of volcanology.

The NHI application, available online without any authentication at the web address https://nicogenzano.users.earthengine.app/view/nhi-tool, allows you to select from a list of more than 1400 volcanoes assets, the area and the period of interest and the extent of the region to be studied (represented by a circle of variable radius around the main crater) ... "

Sources: Boris Behncke and INGVvulcani.

 Etna - example of the NHI application, available online - Doc. via INGVvulcani 11.05.2020

 Etna - example of the NHI application, available online - Doc. via INGVvulcani 11.05.2020

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
 Sabancaya - summary table of the activity between 4 and 10 May 2020 - Doc. I.G.Peru

Sabancaya - summary table of the activity between 4 and 10 May 2020 - Doc. I.G.Peru

In Sabancaya, the IGP recorded and analyzed the presence of approximately 380 earthquakes of volcanic origin, associated with the circulation of fluids (magma, gas, etc.) inside the volcano, in the week of 4 as of May 10, 2020.

Between May 4 and 6, earthquakes of magnitude M3 occurred : seven to M3.0, located between 12 km to 15 km north and northeast of the volcano, near the populated centers of Maca and Pinchollo , respectively. These events would be associated with the tectonic and volcanic activity of the area.

In addition, on average 11 daily explosions of low to medium intensity were recorded; the ash and gas plumes reached up to 3,000 meters above the summit, with a dispersion going from east to north of the volcano. Between May 5 and May 7, a slight ash fall was reported in the districts of Lari, Macay Achoma, located northeast of the volcano.

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

Satellite surveillance has identified the presence of 4 thermal anomalies with heat between 1 MW and 33 MW, associated with the presence of a lava body (dome) on the surface of the volcano crater.

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

 

Source: I.G. Peru
 

Lō 'ihi submarine volcano - seismic swarm of 11.05.2020 - USGS / HVO map

Lō 'ihi submarine volcano - seismic swarm of 11.05.2020 - USGS / HVO map

On May 11, 2020, a seismic swarm, consisting of 35 earthquakes of magnitude greater than 2.0, was detected around the submarine volcano Lō 'ihi, ~ 30 miles off Ka Lae (South Point). The 3 largest so far have occurred between 12-1 p.m. local measuring M3. 9, M3. 7 & M3. 8, the map showing 56 earthquakes in the region in the past 2 weeks.

Most events are in a depth range of 4-7.5 mi, with a few smaller events indicating more subtle adjustments.

These earthquakes are observed by seismometers located on Big Island, and have a relative resolution.

 

Source: USGS - HVO

Piton de La Fournaise - 11.05.2020 - zone of the eruption of 2-6.04.2020 - Difficult denomination: a crater or an eruptive crack - photo OVPF / SAG / PGHM

Piton de La Fournaise - 11.05.2020 - zone of the eruption of 2-6.04.2020 - Difficult denomination: a crater or an eruptive crack - photo OVPF / SAG / PGHM

At Piton de La Fournaise, OVPF scientists are back on the volcano, from the first hours of deconfinement. An overview of the eruption zone from 2 to 6 April 2020 could be carried out, with the assistance of SAG and the PGHM, as well as lava samples.

Results are expected in the following days

 

Source: OVPF / Twitter

Piton de La Fournaise - 11.05.2020 - Dolomieu area affected by the eruption of 2-6.04.2020 - photo OVPF / SAG / PGHM

Piton de La Fournaise - 11.05.2020 - Dolomieu area affected by the eruption of 2-6.04.2020 - photo OVPF / SAG / PGHM

Piton de La Fournaise - 11.05.2020 - zone of the eruption of 2-6.04.2020 - photo OVPF / SAG / PGHM

Piton de La Fournaise - 11.05.2020 - zone of the eruption of 2-6.04.2020 - photo OVPF / SAG / PGHM

Piton de La Fournaise - 11.05.2020 - Removal of scientists in the area of ​​the April eruption - photo OVPF / SAG / PGHM

Piton de La Fournaise - 11.05.2020 - Removal of scientists in the area of ​​the April eruption - photo OVPF / SAG / PGHM

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Publié le par Bernard Duyck
Publié dans : #volcanic activity
Etna NSEC - 10.05.2020 / 00h21 weak Strombolian explosion at the "saddle cone" of the new crater of the Southeast - photo Boris Behncke

Etna NSEC - 10.05.2020 / 00h21 weak Strombolian explosion at the "saddle cone" of the new crater of the Southeast - photo Boris Behncke

During the first hours of May 10, 2020, a new episode of modest Strombolian activity took place in the "saddle cone" of the New Crater southeast of Etna.

The INGV OE reports that the surveillance networks recorded at 03:27 hours (01:27 UTC), a continuous strombolian activity, with an ejection of products beyond the crater. Some blocks partially accumulate at the edge of the crater while others roll along the slopes.
At the same time as the eruptive activity of the New Southeast Crater, there is also an increase in the eruptive activity of Voragine, with ballistic ejections beyond the crater edge.

From approximately 04:00 hours, there is a significant decrease in Strombolian activity in the New Crater of Southeast, where a strong degassing remains. At La Voragine crater, an explosive activity is less strong and frequent than the previous hours.

Etna - 10.05.2020 - simultaneous explosions with Voragine (on the left) and with the saddle cone of the SEC-webcam therm. Montagnola 0h54 - stronger explosion in the saddle cone - visible webcam Montagnola 01h00 - one click to enlargeEtna - 10.05.2020 - simultaneous explosions with Voragine (on the left) and with the saddle cone of the SEC-webcam therm. Montagnola 0h54 - stronger explosion in the saddle cone - visible webcam Montagnola 01h00 - one click to enlarge

Etna - 10.05.2020 - simultaneous explosions with Voragine (on the left) and with the saddle cone of the SEC-webcam therm. Montagnola 0h54 - stronger explosion in the saddle cone - visible webcam Montagnola 01h00 - one click to enlarge

As for the amplitude of the volcanic tremor, it showed a sudden increase from 11:30 p.m. UTC on May 9, reaching its maximum value around 12:30 p.m. UTC on May 10, and then remained at high values. A rapid decline is observed, with a return to average levels around 02:20 UTC on May 10.

The location of the source of the tremor is located near the area of ​​the New Southeast Crater, at a depth of about 2800-3000 meters above mean sea level.

Etna - variation of the amplitude of the tremor at 10.05.2020 / 9.10 am - Doc. INGV OE

Etna - variation of the amplitude of the tremor at 10.05.2020 / 9.10 am - Doc. INGV OE

In Kamchatka, volcanic activity marks the volcanoes Ebeko, Klyuchevskoy, and Karymsky.

In Klyuchevskoy, Strombolian activity persists, with a lava flow on the south-eastern flank, and gas and ash explosions, with a cloud spotted at 5,500-6,000 meters extending over 50 km to the east.

At the Ebeko, an explosion of gas and ash is observed, with a plume at 1,500 meters asl., Drifting towards the southwest over 5 km.

In Karymsky, an emission of gas and vapor, containing a little ash, is located by the satellites, drifting up to 77 km to the ESE of the volcano.

Aviation codes are orange for Klyuchevskoy and Ebeko, yellow for Karymsky.

 

Source: KVERT & VAAC Tokyo

Karymsky - photo archive KVERT 09.09.2019 / А. Маневич. ИВиС ДВО РАН, KVERT

Karymsky - photo archive KVERT 09.09.2019 / А. Маневич. ИВиС ДВО РАН, KVERT

At Fuego, a change in the type of activity is recorded by the seismic and acoustic networks from May 5, 2020 .

On the evening of May 8, Insivumeh reports that a lava flow has been observed since the morning, in the direction of Barranca Ceniza reaching a length of about 400 meters. It is accompanied by almost constant incandescence at the crater and avalanches towards the vegetation zone over 1 km. The explosions remain weak to moderate, with shock waves and ash plumes reaching 4,800 m. asl.

 

Sources: Insivumeh & Sentinel-2

Fuego - 09.05.2020 - Sentinel image 2 bands 7,6,2 / Insivumeh - one click to enlarge

Fuego - 09.05.2020 - Sentinel image 2 bands 7,6,2 / Insivumeh - one click to enlarge

Fuego - 10.05.2020 - Sentinel-2 L1C bands 12,11,4 image - one click to enlarge

Fuego - 10.05.2020 - Sentinel-2 L1C bands 12,11,4 image - one click to enlarge

An overview of Nishinoshima, in the Ogasawara Islands in southern Japan, was conducted by the Japan Coast Guards on April 29, 2020.

The surface of the slag cone has been renewed and deposits of sulfur can be seen in places on the northeast surface of the cone.

Although it cannot be seen from the front of the image, it appears that the collapsed crater southwest of the summit that appeared on April 19 has been buried again. Between April 29 and the previous sighting on April 19, there was obviously a good activity.

Thermal images are also interesting. Although the exit is the same, you can see the lava flow move clockwise through the pyroclastic cone and head south. A beautiful fan of lava in the north direction, and a flow to the east coast consists of three arms.

 

Source: Japan Coast Guards - link via Shérine France

Nishinoshima - summit of the active cone and sulfur deposits on 04.29.2020 / 12:40 p.m. - photo Japan Coast Guards

Nishinoshima - summit of the active cone and sulfur deposits on 04.29.2020 / 12:40 p.m. - photo Japan Coast Guards

Nishinoshima - lava flow at sea - 04.29.2020 / 12:30 p.m. - photo Japan Coast Guards

Nishinoshima - lava flow at sea - 04.29.2020 / 12:30 p.m. - photo Japan Coast Guards

 Nishinoshima - thermal camera image of the lava flows on April 29, 2020 / 12:30 p.m. - photo Japan Coast Guards

 Nishinoshima - thermal camera image of the lava flows on April 29, 2020 / 12:30 p.m. - photo Japan Coast Guards

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Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Historical eruptions

Geologists from the Geologische Dienst Nederland (GDN) have discovered in recent studies a new volcano in the subsoil of the North Sea northwest of the island of Texel (Friesian archipelago).

He was baptized Mulciber, "who wields iron", one of the nicknames of Vulcan, the Roman god of fire and volcanoes.

 Respective location of Zuidwal and Mulciber volcanoes. - Doc.TNO

Respective location of Zuidwal and Mulciber volcanoes. - Doc.TNO

Since 1985, volcanic ash had been discovered during drilling. Until recently attributed to the Zuidwal volcano (see related article), located in the Wadden Sea northeast of Texel and a hundred kilometers away, the new volcano was discovered during an investigation into the rock layers of the Upper Jurassic, under several kilometers of sediment, at 3,000 meters below sea level. These two volcanoes had a brief activity around 150 million years ago.

Mulciber Volcano - The top of the basalt layer imaged using 3D seismic, about 3 km deep. The red elevation shows the location of the volcano itself. In the seismic section, we can see that younger overlying rocks are bent over the volcano (Source: TNO)

Mulciber Volcano - The top of the basalt layer imaged using 3D seismic, about 3 km deep. The red elevation shows the location of the volcano itself. In the seismic section, we can see that younger overlying rocks are bent over the volcano (Source: TNO)

Striking deviations in the structure of the subsurface and the Earth's magnetic field at the site, together with the presence of basalt, made one think of a new volcanic structure. The 3D images suggest the structure of the volcano.

The strong positive deviation from the normal geomagnetic field is caused by the large concentrations of magnetic minerals, such as iron oxide and magnetite, common in volcanic rocks. It is comparable to that encountered at the Zuidwal volcano.

The volcanism of the place can be explained by the tectonic processes resulting from the disintegration of the Pangea supercontinent, with rifting, with which volcanism is often associated. Jurassic rifting did not continue in the North Sea, but the magma which rose may have created deposits of igneous rocks and volcanism. Then, the upheavals continued in the upper Cretaceous (100 to 66 Ma) with the inversion of the grabens of the south of the North Sea, in probable link with the Alpine orogeny, and the collision between the African and European plates.

Jurassic volcanism in the North Sea - tectonic reconstruction by Douwe van Hinsbergen and Eldert Advokaat from the University of Utrecht, illustrating the context in which the newly discovered and extinct Mulciber volcano and the already known Zuidwal volcano were active some time ago about 150 million years ago. - Doc. Michiel van der Meulen / Viméo

This brings the number of Dutch volcanoes to four: two extinct in the North Sea and two active in the Caribbean, the Mount Scenery in Saba (GVP / https://volcano.si.edu/volcano.cfm?vn=360010) and the Quill in Saint-Eustache (GVP / https://volcano.si.edu/volcano.cfm?vn=360020).

 

Sources: Thanks to my daughter Frédérique for the info (which makes her win an intra-family challenge 2020)

- Media: 7 of 7; RTL News; ad, nl

- TNO, nl - TNO discovers a volcano 150 million years old in the North Sea.

- Wetenschap.nu - Discovery of a new volcano in the Dutch basement after Geert-Jan Vis

- Global Volcanism Program - Saba and Quill

- The dismemberment of Pangea: from Jurassic to the present day - http://www2.ggl.ulaval.ca/

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Publié le par Bernard Duyck
Publié dans : #volcanic activity

Etna's activity was characterized between 1 ° and May 7, 2020 by a continuous degassing of the BN / VOR / NEC crater sectors (Bocca Nuova, Voragine, NE crater) and SEC / NSEC crater (SE crater and new SE crater). Explosions continue from the easternmost slag cone inside Voragine. This activity is often violent with the projection into the atmosphere of coarse pyroclastic fragments. Strombolian activity continues at the bottom of the northeast crater.

Since around 5:00 p.m. on May 8, there has been a slight increase in ash emissions from the NSEC, this pulsating activity has formed a plume of diluted ash towards the ESS. INGV personnel present near the new southeast crater observed a strong degassing, with deep roars and associated ash emissions. As for the amplitude of the volcanic tremor, it oscillates on medium-high values; the source of the tremor is located near the new southeast crater, at a depth of about 2,800 to 3,000 meters above mean sea level.

Etna NSEC & VOR - white plume and black plume ... what will be the good news? - photo Salvatore lo Giudice

Etna NSEC & VOR - white plume and black plume ... what will be the good news? - photo Salvatore lo Giudice

The infrasonic activity was maintained at generally average values ​​(<1 Pa) with periodic, short-term increases (<12h) characterized by high amplitude events (> 1 Pa) localized both in the BN / VOR / NE crater and that of SE / NSE. On May 3, the earthquake went from average to low values.

Analysis of the thermal activity of the MODIS satellite revealed a thermal peak anomaly of a mainly moderate intensity (max 23 MW), depending on an explosive activity, as recorded by the remaining monitored parameters.

 

Sources: INGV vulcani and L.G.S.

Stromboli - seismicity and infrasonic ratio between 1 ° and 7 May 2020 - Doc. LGS

Stromboli - seismicity and infrasonic ratio between 1 ° and 7 May 2020 - Doc. LGS

In Stromboli, during the week of May 1 to May 7, 2020, the explosive activity remained stable at a low level and was mainly localized in the SW crater until May 1, then decreased slightly and mainly moved towards the central crater. This activity is accompanied by a slight swelling (max 40 mbar) also located in the C-SO sector.

The number of VLP events stable at high values ​​until May 5 then increased to average values ​​(between 10.5 and 10.9 events / hour). The seismic tremor is stable on the average values.

The thermal anomalies of the satellites (MODIS) detected anomalies of low to moderate level (max 22 MW), consistently with a low level of explosive activity.

SO2 fluxes, measured during the week, oscillate between low and average values, recording average values ​​of 61 tonnes / day and 408 tonnes / day respectively.

On May 6, following the comparative analysis of the monitored parameters, the global evaluation of volcanic activity went to low level.

 

Source: L.G.S.

Rincon de La Vieja - photo archive 10.2019 by Edgardo Delgado / Twitter

Rincon de La Vieja - photo archive 10.2019 by Edgardo Delgado / Twitter

At Rincon de La Vieja, a last hydrothermal explosion occurred on May 8 at 3:43 am local; due to the cloud cover in the crater, the height of the plume remains unknown.

The Ovsicori reports tremor in bands in the range of 1 to 5 Hz, sometimes discontinuous.

The activity level is 3 out of 5 /

 

Source: Ovsicori

Steamboat geyser - the 13th eruption, right on the Tantalus gauge / Norris junction YNP

Steamboat geyser - the 13th eruption, right on the Tantalus gauge / Norris junction YNP

At Yellowstone National Park, the Steamboat geyser experienced its 13th eruption in 2020 on May 8 at 1:05 a.m. MDT. The nearest seismic and temperature sensors were offline due to a power failure, but the event was detected by another seismometer and the Tantalus Creek gauge.

 

Source: USGS volcanoes

Clarification on the Sakurajima eruption of yesterday May 8, 2020 - possible pyroclastic flow in the direction of Kagoshima bay

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