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Earth of fire

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

Articles avec #actualites volcaniques catégorie

Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques

Contact resumption in photos and news briefs on the volcanic events, after several days of absence due to eclipse.

In Chile, the Villarica, in orange alert with 5 km restriction zone, present since a few days a Strombolian activity accompanied by ballistic projectiles out crater. In the photos of the thermal camera, night glow at the top is permanent, foreshadowing the return of the lava lake. The tremor associated with fluid dynamics inside the volcano is reported by the SERNAGEOMIN

Sources: SERNAGEOMIN - OVDAS & Povi
 

Villarica - 03/25/2015 - Thermal camera shows the summit thermal anomaly - doc.Sernageomin / Twitter
Villarica - 03/25/2015 - Thermal camera shows the summit thermal anomaly - doc.Sernageomin / Twitter

Villarica - 03/25/2015 - Thermal camera shows the summit thermal anomaly - doc.Sernageomin / Twitter

Villarica - increasing of the strombolian activity between 22 and 25 March 2015 - Doc. Povi

Villarica - increasing of the strombolian activity between 22 and 25 March 2015 - Doc. Povi

Villarica - map of risk areas updated in the prevailing winds - Doc. SERNAGEOMIN

Villarica - map of risk areas updated in the prevailing winds - Doc. SERNAGEOMIN

In Mexico, Colima continues to produce explosions "vulcanian" type. On 24 March, an eruption took place at 3:08 local, accompanied by fontaining of several hundred meters and a small pyroclastic flow.

A survey by the scientists in charge of the volcano at the University of Colima Wednesday revealed that the crater has taken an oval shape with a diameter ranging from 170 to 190 meters and a depth exceeding 30 meters.

 

 Colima - 2015.03.24 / 3:15 loc. - Photo Hernando Rivera / Twitter

Colima - 2015.03.24 / 3:15 loc. - Photo Hernando Rivera / Twitter

Colima - left, lenticular cloud on March 25, 2015 / 6:58 - right, explosion on March 26 at 11:26 - a click to enlarge - photos webcamsdemexicoColima - left, lenticular cloud on March 25, 2015 / 6:58 - right, explosion on March 26 at 11:26 - a click to enlarge - photos webcamsdemexico

Colima - left, lenticular cloud on March 25, 2015 / 6:58 - right, explosion on March 26 at 11:26 - a click to enlarge - photos webcamsdemexico

Colima - the crater during an inspection by the University of Colima on 25.03.15 / Carlos Navarro Ochoa

Colima - the crater during an inspection by the University of Colima on 25.03.15 / Carlos Navarro Ochoa

In Kamchatka, the Shiveluch has introduced this March 26 to 10am local an explosion accompanied by an ash plume that rose to 10 km. asl. before spreading to the south, and a pyroclastic flow of about 1,000 meters in length, causing snow melt.

The Zhupanovsky presented on March 25 an emission of ash and a plume amounting to 8,000 m. before spreading eastward, spotted by VAAC Tokyo.

The Karymsky in ongoing activity, knows intermittent Strombolian explosions, which are accompanied by small plumes, enough to be spotted by the services of VAAC Tokyo.

Sources: KVERT & Volkstat

Shiveluch - eruption 26/03/2015 - photo Y.Demyanchuk / Volkstat.ru

Shiveluch - eruption 26/03/2015 - photo Y.Demyanchuk / Volkstat.ru

In the Aleutian arc, the Semisopochnoi saw its seismic activity increased in recent days, and a  change of the alert codes : yellow aviation code, volcanic alert "Advisory".

Brief periods of tremor were added, indicating magma and/or gas movement. Last activity date of April 1987.

Sources: VONA & AVO

 

The summits of Semisopochnoi - Doc. NASA EO

The summits of Semisopochnoi - Doc. NASA EO

Semisopochnoi Location in the Aleutian volcanic arc / Alaska - Doc. AVO / Janet Schaefer

Semisopochnoi Location in the Aleutian volcanic arc / Alaska - Doc. AVO / Janet Schaefer

On Sumatra, the new (recent) dome of Sinabung is always bigger and threat of collapse. The few new from VSI on this activity are fortunately compensated by photographers on site.
 

The new dome Sinabung March 24, 2015 / 10:02 - photo endrolew @

The new dome Sinabung March 24, 2015 / 10:02 - photo endrolew @

Sinabung: the steaming and precariously dome, March 25, 2015 / 6:37 p.m. - photo endrolew @

Sinabung: the steaming and precariously dome, March 25, 2015 / 6:37 p.m. - photo endrolew @

Sinabung:  Incandescent rockfalls 26.03.2015 / 18h02 loc - photo endrolew @

Sinabung: Incandescent rockfalls 26.03.2015 / 18h02 loc - photo endrolew @

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Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques

A report by the IGEPN / 16.03 set an update on the Sangay's activities of the last few weeks.

In the first days of 2015, new lava flows were issued on the southeast flank. The extension of the lava is around 900 meters from the crater, and the blocks and ash deposits extend over 2500 m. ESE direction. The presence of blocks and ash is shown on the south side also, produced by the explosive activity of the volcano. Emissions of ash plumes were observed by the inhabitants of centers for miles.

 

Sangay in January 2015 - Foto cortesía Gustavo Cruz / IGEPN

Sangay in January 2015 - Foto cortesía Gustavo Cruz / IGEPN

Activity of Sangay since January : lava flows, ash and blocs deposits - Doc. IGEPN

Activity of Sangay since January : lava flows, ash and blocs deposits - Doc. IGEPN

The Mirova system detected the thermal anomalies; 21 episodes qualified from low to moderate were recorded between January 31 and February 25, 2015.

The activity of the Sangay is qualified "high" between 27 February and 12 March, with 839 earthquakes LP, 165 type earthquakes of tornillo type, 118 explosions, 3 episodes of tremor and 3 emissions.

 

Sangay by Mirova - Radiative power last month

Sangay by Mirova - Radiative power last month

The Sangay, located in the province of Chimborazo in Ecuador, is considered by the GVP as erupting from August 1934 to date.

The almost constant activity of this predominantly andesitic volcano has caused frequent changes in the morphology of the summit crater complex.

Sangay Location in the province of Chimborazo - Map of volcanic hazards / from an online posting by Ordonez and others, 2014
Sangay Location in the province of Chimborazo - Map of volcanic hazards / from an online posting by Ordonez and others, 2014

Sangay Location in the province of Chimborazo - Map of volcanic hazards / from an online posting by Ordonez and others, 2014

IGEPN - Repair of an eccentrically monitoring station on the Sangay between 25.02 and 02.03.2015

Sources :

- IGEPN - Evaluación de la actividad eruptiva 16.03.2015 - link

- Global Volcanism Program - Sangay

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Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques
The eye of Hurricane Pam March 12, 2015 / 2:11 - Doc. NOAA / NASA RAMMB / CIRA

The eye of Hurricane Pam March 12, 2015 / 2:11 - Doc. NOAA / NASA RAMMB / CIRA

Pam cyclone of Category 5 ... the stronger, passed over the Vanuatu archipelago.

Satellite photos show that this monster covers 83 islands, inhabited by some 260,000 inhabitants, particularly affecting the islands to the east of the archipelago.


 

Pam cyclone formation on 03/10/2015 - Doc. NOAA MTSAT

Pam cyclone formation on 03/10/2015 - Doc. NOAA MTSAT

Path of the cyclone Pam, on March 13 and following days

Path of the cyclone Pam, on March 13 and following days

The eye of the storm on Tanna / Vanuatu - Doc. CNN World Weather

The eye of the storm on Tanna / Vanuatu - Doc. CNN World Weather

Earlier Saturday, the east side of the eye of the storm passed on Tanna Island (population 30,000 inhabitants), where it was noted winds of 300 km / h (Fiji's Weather).

The east coast of the island of Tanna was particularly struck: the first reports speak of incredible destruction, end of the world ... "it is as if a bomb had fallen on the city center; there is no electricity, more water, more media ". The streets are littered with trees, roof pieces of metal. The New Zealand High Commission in Port Vila, supposed to withstand cyclones, was heavily damaged.

Whole villages were destroyed in remote areas.

The death toll would be around a dozen, and about twenty wounded, but UNICEF workers say it will take days if not weeks before we know the full impact of this disaster.

First evidence of destructions - photos UNICEF Pacific
First evidence of destructions - photos UNICEF Pacific

First evidence of destructions - photos UNICEF Pacific

The airport of Port Vila, the capital, is flooded and trees litter the track. The closure of this airport prevents a rapid humanitarian response. The local government wants to open it to military flights and Australia and New Zealand have units on standby (IRIN)

The islands of Erromango and Aneityum, less populated, were directly affected then.

The cyclone is moving now towards the north-eastern tip of New Zealand, and should lose its violence this Sunday or Monday. Heavy precipitations are expected in this area.

 

The cyclone over the eastern side of the Vanuatu archipelago - Doc. Terra Modis 13.03.2015 / 1:10 UTC

The cyclone over the eastern side of the Vanuatu archipelago - Doc. Terra Modis 13.03.2015 / 1:10 UTC

Humanitarian needs are going to be huge ... to contribute to the efforts of local institutions that assist victims, you can do so via the following websites:

Red Cross AU

--CARE Australia

Oxfam Australia

World Vision

--Samaritans Purse

Save the Children

 

Sources :

Unicef Vanuatu, IRIN, Stuff.nz

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Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques

The Cassini spacecraft orbiting around Saturn has detected microscopic particules of rocks, related to the hydrothermal activity on the ocean floor of the moon Enceladus.

A 2014 study suggests the presence of a deep ocean under the ice cap of Enceladus, thick of 30 to 40 km.
 

Plumes of Enceladus - photo NASA JPL

Plumes of Enceladus - photo NASA JPL

The studies, made on four years, showed that these grains are formed when hot water at at least 90 ° C, containing dissolved minerals from rocks of Enceladus internal, an icy moon of Saturn, contacts colder water. The meeting causes condensation of minerals and the formation of floating micro-silica grains in water. To avoid too much fat, the silica grains must pass between several months and several years to move from the bottom of the inner ocean to the surface of Enceladus before being incorporated into larger ice grains at the vents that connect the ocean to the surface of Enceladus. After their ejection into space via the geysers, ice grains erode, releasing rock inclusions detected by Cassini.

The origin of the energy needed for hydrothermal process is not well understood at the moment, but probably includes a heating associated with tides produced by Enceladus orbits around Saturn, radioactive decay of the heart, and chemical reactions.
 

Artist's impression showing hydrothermal activity on the seafloor subsurface Enceladus under the ice cap - Doc. Copyright NASA / JPL-Caltech 03/11/2015

Artist's impression showing hydrothermal activity on the seafloor subsurface Enceladus under the ice cap - Doc. Copyright NASA / JPL-Caltech 03/11/2015

Diagram illustrating the potential origin of the methane found in gas plumes from encelade - Credit Ion and Neutral Mass Spectrometer on NASA's Cassini mission. / Southwest Research Institute

Diagram illustrating the potential origin of the methane found in gas plumes from encelade - Credit Ion and Neutral Mass Spectrometer on NASA's Cassini mission. / Southwest Research Institute

Scientists in charge of Cassini also report the abundance of methane injected into the environment of Enceladus ... it would be produced by hydrothermal processes at the water-rock interface at the bottom of the subsurface ocean of Enceladus, or by melt of a type of methane-rich ice before it surface percolation, or by the combination of two mechanisms.

Saturn's moon show signs of a present hydrothermal activity similar to the one observed in terrestrial ocean depths ... which opens horizons on environments adapted to life of living organisms.

The Cassini
-Huygens mission is a cooperative project of NASA, ESA / European Space Agency and the Italian Space Agency.

 

Sources :

- ESA / Cassini-Huygens  - Hot water activity on icy moon’s seafloor - link

- Nasa JPL – 11.03.2015 - Spacecraft Data Suggest Saturn Moon's Ocean May Harbor Hydrothermal Activity - link 1 - link 2

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Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques
Hawaii, Big Island and volcanoes, February 18, 2015 - From the International Space Station, the European Space Agency astronaut by Samantha Cristoforetti

Hawaii, Big Island and volcanoes, February 18, 2015 - From the International Space Station, the European Space Agency astronaut by Samantha Cristoforetti

Ads of West Hawaii Today reports that Christina Neal was chosen as New Scientist in charge of the HVO / USGeological Survey's Hawaiian Volcano Observatory. She took office on Sunday, World Day for Women's Rights, and succeeds Jim Kauahikua, who held the post for ten years. This is the second woman to lead the HVO in 103 years.


On the left, Tina Neal on the ground at the Okmok volcano - right, official photo as New Scientist in charge of the HVO in 2015 - Click here to see the entire photo.

On the left, Tina Neal on the ground at the Okmok volcano - right, official photo as New Scientist in charge of the HVO in 2015 - Click here to see the entire photo. On the left, Tina Neal on the ground at the Okmok volcano - right, official photo as New Scientist in charge of the HVO in 2015 - Click here to see the entire photo.

On the left, Tina Neal on the ground at the Okmok volcano - right, official photo as New Scientist in charge of the HVO in 2015 - Click here to see the entire photo.

She knows well the Observatory in Hawaii, having worked there between 1983 and 1989, and Kilauea and Mauna Loa volcanoes. She participated in the monitoring of Kilauea in the early days of the eruption on the East Rift Zone, as well as the eruption of Mauna Loa in 1984.

From 1990 to 1998, she worked at the AVO / Alaska Volcano Observatory, where she studied and monitored the different volcanoes in charge of the Observatory, and the eruptions of Redoubt (1989-1990, 2009), Mount Spurr ( 1992), the Augustine (2005-2006) and Okmok (2008).

In 1998, she held the position of first USGS advised the Office of Foreign Disaster Assistance, responsible for the coordination of US responses to disasters abroad, before returning to the AVO in 2000, where she resumes his geologist position while keeping specific missions to the HVO.

Sources:
- USGS - New Hawaiian Volcano Observatory Scientist-in-Charge Christina Neal Takes Top Spot at USGS HVO -
link
- Big Island now - Christina Neal Joins HVO as Scientist-in-Charge

In this photo of ISS042-E-281151 / 18.02.2015, the VOG (fog composed of gas and fine particles  and droplets of acids aerosols, created by interaction between sulfur dioxide, other gases and sunlight, air, moisture and dust / HVO) is carried on more than one hundred kilometers and forms  von Kármán vortex.

In this photo of ISS042-E-281151 / 18.02.2015, the VOG (fog composed of gas and fine particles and droplets of acids aerosols, created by interaction between sulfur dioxide, other gases and sunlight, air, moisture and dust / HVO) is carried on more than one hundred kilometers and forms von Kármán vortex.

A study in Earth and Planetary Science letters of March 2015 provides details about the Kilauea plumbing system, based on lead isotope analysis in lavas from the top.

In summary,

The summit magmatic reservoir of Kilauea has two magmatic bodies, at least since 1971:  ratio Pb206/ Pb204 in lavas of Halama'uma'u indicates that eruptions since 1971 have been fueled by a magma chamber between 2 and 4 km below the southern edge of the caldera of Kilauea, and another shallower reservoir, located less than 2 km. under the edge of the pit crater of Halema'uma'u.

This surface reservoir would have held only ~0.1-0.5 km3 of magma during the late 20th century ... which means that large eruptions of Kilauea, like the current one (which has issued more than 4 cubic kilometers of magma) must therefore be supported by a substantially continuous supply of molten material from the mantle.

The proposed model shows at least four magmas from the mantle, of distinct compositions, were issued by the Kilauea since 1959. This means that the eruptive behavior of Kilauea is partially related to the delivery of new magma batches from the source region of the volcano in the Hawaiian mantle plume.

Plumbing Cross section of Kilauea / below the summit caldera of Kilauea, with the lava lake in Halema'uma'u crater (4) - Credit: Aaron Pietruzska - EPSL

Plumbing Cross section of Kilauea / below the summit caldera of Kilauea, with the lava lake in Halema'uma'u crater (4) - Credit: Aaron Pietruzska - EPSL

The summit caldera of Kilauea - Nasa / Ali 15.07.2010

The summit caldera of Kilauea - Nasa / Ali 15.07.2010

Pietruszka however note that separate geophysical measurements suggest the size of the magma chamber largest ... signifying the presence of a greater amount of molten rock indicated by chemical analysis. But many researchers now believe that in the volcanic reservoirs, like those in Kilauea, the rock is more like a melted mixture (a slushy porridge), a mixture of hot crystals surrounded by magma.

Pietruszka concluded with a quip: "geochemists consider the fluid part of the system, while geophysicists longer see the movements of magma and the hot and deformable crystals".

 

Source :

Earth and Planetary science letters mars 2015 - Two magma bodies beneath the summit of Kīlauea Volcano unveiled by isotopically distinct melt deliveries from the mantle - by Aaron J. Pietruszka & al.

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Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques
Sinabung - the new lava lobe in manifest imbalance on March 3 / 12:45 - photo endrolew@

Sinabung - the new lava lobe in manifest imbalance on March 3 / 12:45 - photo endrolew@

The new lobe Sinabung, rapidly growing since the last major pyroclastic flow, marked a dangerous imbalance on March 3, 2015, shown in the photo above.

That night, a (partial but important) collapse was accompanied by a large pyroclastic flow that has spread 4.5 km to the south, and forest fires. The plume was approximately 3,000 meters, much higher after the
VAAC Darwin.

The penetration of the pyroclastic flow in the Lao river caused a secondary reaction, with a white cloud of steam at the meeting between the pyroclastic flow and the cold waters of the river.

 

Sinabung - Activity 04 and March 5 - photos L.K.Adam / Twitter / Beidar Sinabung

Sinabung - Activity 04 and March 5 - photos L.K.Adam / Twitter / Beidar Sinabung

Sinabung - partial collapse of the lava lobe March 5, 2015 - photo Sadrah ps

Sinabung - partial collapse of the lava lobe March 5, 2015 - photo Sadrah ps

Sinabung - plume of the interaction between the waters of the river Lao and the pyroclastic flow - photo PVMBG

Sinabung - plume of the interaction between the waters of the river Lao and the pyroclastic flow - photo PVMBG

Sinabung - the pyroclastic flow buried the few remains of the village (evacuated) of Sukameriah 05/03/2015 - photo left endrolew@ - the remains of the village of Sukameriah, February 18, 2015 -  right, photo Sadrah Peranginangin - a click to enlarge. Sinabung - the pyroclastic flow buried the few remains of the village (evacuated) of Sukameriah 05/03/2015 - photo left endrolew@ - the remains of the village of Sukameriah, February 18, 2015 -  right, photo Sadrah Peranginangin - a click to enlarge.

Sinabung - the pyroclastic flow buried the few remains of the village (evacuated) of Sukameriah 05/03/2015 - photo left endrolew@ - the remains of the village of Sukameriah, February 18, 2015 - right, photo Sadrah Peranginangin - a click to enlarge.

Sinabung - left, destruction after the pyroclastic flow - photo Thomas Sitepu 05.03.2015 - right, a field of coffee trees affected by pyroclastic flow - photo endrolew@ Sinabung - left, destruction after the pyroclastic flow - photo Thomas Sitepu 05.03.2015 - right, a field of coffee trees affected by pyroclastic flow - photo endrolew@

Sinabung - left, destruction after the pyroclastic flow - photo Thomas Sitepu 05.03.2015 - right, a field of coffee trees affected by pyroclastic flow - photo endrolew@

Sources:

- PVMBG & VAAC Darwin

- Twitter - via  Beidar Sinabung / Mbah Lëwa / Léopold Adam

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Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques
 Villarica - 01.03.2015 - Strombolian projections - photo Patricio Garrido on Twitter

Villarica - 01.03.2015 - Strombolian projections - photo Patricio Garrido on Twitter

SERNAGEOMIN increased the alert level of Villarica / Chile at Orange this March 2, 2015, following an increase in tremor reaching as high values ​​considered for this volcano (three times compared to the values ​​set yellow alert level setting Place on February 6).

In addition, the level of the lava lake seems closer to the rim of the crater, and an strombolian eruptive process, interrupted and weak emerged, characterized by the emission of gases and visible ballistic projectiles at night. This type of activity has intensified in the early morning on March 2, with projections up to 500- 600 m from the center of the crater, and impact on the sides (see photos below desous & thermal anomaly Modvolc).

 

Villarica - photo Hector Andrade / Soychile.cl 02/03/2015

Villarica - photo Hector Andrade / Soychile.cl 02/03/2015

Villarica summit, covered with ash, and small strombolian activity in the crater - photo 03.02.2015 SERNAGEOMIN

Villarica summit, covered with ash, and small strombolian activity in the crater - photo 03.02.2015 SERNAGEOMIN

Zoom on the summit of Villarica covered with ash and small strombolian activity in the crater - photo 02.03.2015 SERNAGEOMIN

Zoom on the summit of Villarica covered with ash and small strombolian activity in the crater - photo 02.03.2015 SERNAGEOMIN

Villarica 03/02/2015 - lava flows on the snow of the summit - photo SERNAGEOMIN

Villarica 03/02/2015 - lava flows on the snow of the summit - photo SERNAGEOMIN

Villarica - Thermal anomaly 03/02/2015 - Doc. MODVOLC

Villarica - Thermal anomaly 03/02/2015 - Doc. MODVOLC

A strong strombolian eruption marked the Villarica volcano that on March 3.

A paroxysmal phase, with lava fountains like those that mark the Etna, lasted thirty minutes ... we expect a report from SERNAGEOMIN.

Onemi set the red alert for Villarica this day

 

Villarica 03/03/2015 - lava fountain and beautiful plume - photo Twitter / christianpino

Villarica 03/03/2015 - lava fountain and beautiful plume - photo Twitter / christianpino

Villarica 03.03.2015 / 3:50 SERNAGEOMIN webcam, left - right, fountain of lava from Trufulco - photo Twitter Omar Morales - a click to enlargeVillarica 03.03.2015 / 3:50 SERNAGEOMIN webcam, left - right, fountain of lava from Trufulco - photo Twitter Omar Morales - a click to enlarge

Villarica 03.03.2015 / 3:50 SERNAGEOMIN webcam, left - right, fountain of lava from Trufulco - photo Twitter Omar Morales - a click to enlarge

Sources :

- Sernageomin - link

- Soychile - El volcán Villarrica tuvo anoche otra jornada de intensa actividad

            El Sernageomin aumentó a "naranja" la alerta técnica sobre el volcán Villarrica

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Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques
Holuhraun: the glow disappeared at Baugur crater - photo Volcano Air Iceland

Holuhraun: the glow disappeared at Baugur crater - photo Volcano Air Iceland

An overview of the eruption site Holuhraun on February 27, 2015 did not see glow at the Baugur crater. The pictures below allow to see the gradual disappearance of the glow in the last month.

It seems that the new magma arrives no more in surface ... but sometimes volcanic gases continue to be emitted both at the eruptive site as
at the lava field. An automatic sensor located in Blönduós (North Iceland) shows 500 mcg / m³ SO2 on 26 February.

The intensity of earthquakes decreases at the intrusive dyke with a maximum magnitudes of 1.3-1.4 since 24.02.

A video from Norðurflug helicopter pilot, Gísli Gíslason, shows that molten lava is no longer visible on the surface of the volcanic crater.

Holuhraun - an agitated lava lake on February 7, 2015 - photo Skynamic

Holuhraun - an agitated lava lake on February 7, 2015 - photo Skynamic

Holuhtraun - on February 21, 2015 only a point of incandescence - photo Biwak TV

Holuhtraun - on February 21, 2015 only a point of incandescence - photo Biwak TV

Seismic activity continues to decline in Bárðarbunga where no earthquake greater than 3 occurred since February 21.


GPS measurements at the Vatnajokull glacier continue to show a slow deflation towards the Bárðarbunga, according to the Met Office, indicating magma movement beneath the volcano.


Subsidence of the caldera is measured at 5 cm. this past week day.

Subsidence of the glacier overcoming the caldera Bárðarbunga and earthquakes in the area from 26 to 02/28/2015 - Doc. University of Iceland, the Icelandic Met Office, the Civil Protection department of the NCIP and the Icelandic Coastal Survey.

Subsidence of the glacier overcoming the caldera Bárðarbunga and earthquakes in the area from 26 to 02/28/2015 - Doc. University of Iceland, the Icelandic Met Office, the Civil Protection department of the NCIP and the Icelandic Coastal Survey.

Location and magnitude of earthquakes on the Vatnajökull 28/02/2015 at 9:40 am - Doc. IMO
Location and magnitude of earthquakes on the Vatnajökull 28/02/2015 at 9:40 am - Doc. IMO

Location and magnitude of earthquakes on the Vatnajökull 28/02/2015 at 9:40 am - Doc. IMO

The Department of Civil Protection and Emergency Management (IMO website) notes in his scientific report of 28 February at 10 am as:

- The eruption, which began at Holuhraun August 31, 2014, ends ... the alert aviation code for Bárðarbunga was lowered from orange to yellow.

YELLOW: Volcano is experiencing signs of elevated unrest Known Above background levels. gold, After A change from Higher alert level:
Volcanic activity HAS Decreased Significantly goal continuous To Be étroitement be monitored for Renewed Increase.
ORANGE: Volcano is Exhibiting Heightened unrest with Increased likelihood of eruption.or, Volcanic eruption is Underway with no or minor ash issuance.


- The gas pollution is still detected around the site eruptive. The area continues to be monitored, and the civil protection remains in alert.

Aviation alert code for Bárðarbunga on 02.28.2015 / 11:40 UTC: yellow - Doc. IMO

Aviation alert code for Bárðarbunga on 02.28.2015 / 11:40 UTC: yellow - Doc. IMO

To follow ... in remembering the possible scenarios outlined in an article of 20 February.

Sources:

- Icelandic Met Office - link

- RÚV - Eldgosinu í Holuhrauni er lokið - link

 

 


 

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Publié le par Bernard Duyck
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Baños de Agua Santa, in the province of Tungurahua, at the foot of the volcano of the same name, is "a city with spa resorts" as the name suggests. - photo Equateurvoyage

Baños de Agua Santa, in the province of Tungurahua, at the foot of the volcano of the same name, is "a city with spa resorts" as the name suggests. - photo Equateurvoyage

Ecuador is home to 54 hot springs. They are associated with tectonic fault systems and / or volcanic.

The IGEPN has studied the physicochemical parameters in 2009; the Institute has just published a report on the fatal dangers of some of them, as well as recommendations.

Distribution of thermal springs in Ecuador, located almost entirely on the volcanic Cordillera - Map IGEPN

Distribution of thermal springs in Ecuador, located almost entirely on the volcanic Cordillera - Map IGEPN

Waters temperatures vary between15 and 74.5 ° C, and a pH of 4.6 to 9.2.

High electrical conductivity is to be related to the presence of various ions in solution: sodium, potassium, magnesium, calcium, fluoride, chloride, bromide, sulfate, bicarbonate and silica.

Various trace elements characterize the waters: Li, Be, Al, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Mo, Cd, Sb, Cs, Ba, Hg , Pb, Th, U, B.

These may be toxic if their concentration exceeds the threshold limit for humans, 5 ppb for arsenic, 1 ppb for mercury, 0.5 ppm for boron. To avoid poisoning both men and animals, it is recommended not to consume these waters without knowing with certainty their chemical composition.
 

Ecuador - pH versus temperaturefor the waters studied by IGEPN

Ecuador - pH versus temperaturefor the waters studied by IGEPN

Some water has a high gas content, either dissolved or free ... which gives them an effervescence. The gas phase consists essentially of CO2 (carbon dioxide), and methane, hydrogen sulfide, carbon monoxide, oxygen, nitrogen, helium, argon and steam.

H2S, CO2 and CO can be dangerous for the living at high concentrations. CO2 is increasingly concentrated in low areas (depressions) and confined spaces, such as the output level of thermal water.

In January 2015, six people were killed in the source Tangali near Otavalo. Two people died when entering the catchment tanks, near the Tungurahua. At Aguas Hediondas, a death occurred in baths releasing H2S.

The IGEPN recommends not to approach the waters where splash of gas located in depressions, not to enter in catchment centers nearby hot springs, not to build saunas directly above water outlet, or hot springs.

Ecuador - a. Source Oyacachi, capture is closed. Closed to the public. - b. Potrerillos in Carchi - source ferruginous bicarbonate, dangerous for its high CO2 content. - c. Capture Nono, closed to the public. - d. capture Pululahua, rich in CO2. This type of capture must be dozens or even hundreds of meters from open public swimming pools- Doc.IGEPN

Ecuador - a. Source Oyacachi, capture is closed. Closed to the public. - b. Potrerillos in Carchi - source ferruginous bicarbonate, dangerous for its high CO2 content. - c. Capture Nono, closed to the public. - d. capture Pululahua, rich in CO2. This type of capture must be dozens or even hundreds of meters from open public swimming pools- Doc.IGEPN

Ecuador - Sampling and physico-chimic measures in sectors of a) Potrerillos, b) Arteson, and c) Aguas Hediondas. - Doc. IGEPN

Ecuador - Sampling and physico-chimic measures in sectors of a) Potrerillos, b) Arteson, and c) Aguas Hediondas. - Doc. IGEPN

Sources:

- Noticias de l'IGEPN - Vertientes termales en el Ecuador y el riesgo / peligro de morir por efecto de los gases burbujeantes - link

- International volcanic health hazard network – volcanic gases and aerosols guidelines - link

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Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques
El Escondido, a new volcano - Observatorio volcanologico de Manizales

El Escondido, a new volcano - Observatorio volcanologico de Manizales

The Volcanological Observatory of Manizales has released the discovery of a new volcano in Colombia, in the Selva de Florencia / Samaná (Caldas).
Studies conducted in 2013 led to the conclusion that this mountainous wooded area housed a crater located at an altitude of 1700 meters asl, consisting of a pyroclatic ring, of 2.000meters diameter, housing a lava domes complex. The work was led by the geologist Maria Luisa Monsalve, with the participation of Ivan Dario Ortiz, Gianluca Norini, Jesús Rueda and Gina Bernardo Rodríguez.

El Escondido - the crater rim (red dot) and the domes - photo Observatorio volcanologico de Manizales

El Escondido - the crater rim (red dot) and the domes - photo Observatorio volcanologico de Manizales

El Escondido : presentation by the geologist  Maria Luisa Monsalve - photos Observatorio volcanologico de ManizalesEl Escondido : presentation by the geologist  Maria Luisa Monsalve - photos Observatorio volcanologico de Manizales

El Escondido : presentation by the geologist Maria Luisa Monsalve - photos Observatorio volcanologico de Manizales

This small building, indistinguishable in the landscape, was named "El Escondido".

Its eruptions, some of which were held there about 30,000 years have produced thick pumice deposits of eight meters in areas near the crater, and a meter in the distal parts, like Ceja ... highlighting the explosiveness the volcano and its potential danger. The extension of the rock deposits is greater than that produced by the Cerro Machin, a volcano considered as the most explosive of Columbia.


Hot springs have been found around El Escondido, but no gas and steam emissions of the crater. No special seismicity was recorded in neighboring municipalities, but the Observatory of Manizales envisages the monitoring of the volcano in the future if necessary.

El Escondido : presentation - photo Observatorio volcanologico de Manizales

El Escondido : presentation - photo Observatorio volcanologico de Manizales

Sources:

- Observatorio Vulcanologico y Sismologico de Manizales – El servicio geologico Colombiano descubre volcan en el oriente de Caldas - link

- El Tiempo - Descubren nuevo volcán potencialmente peligroso en Colombia - link

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