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Earth of fire

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

actu

Publié le par Bernard Duyck
Publié dans : #actu

According to the report of the Volcanological Observatory of Piton de La Fournaise on April 25, various elements are challenging, and suggests that the volcano is still "under pressure" ... Note that the prefecture has not lifted the state of vigilance since the eruption of February 2015 (partial reopening of access to the Enclos, and denying access to the Rivals-Castle Trail).

Piton de la Fournaise - eruptive vent February 9, 2015 - photo OVPF

Piton de la Fournaise - eruptive vent February 9, 2015 - photo OVPF

  Area of the last lava flow of the Piton de la Fournaise - Doc. Telespazio & LMV / OPGC

Area of the last lava flow of the Piton de la Fournaise - Doc. Telespazio & LMV / OPGC

The number of volcano-tectonic earthquakes remains high, with 353 deep volcano-tectonic earthquakes (about 5 km below the summit). Such earthquakes were observed in 1998, before the eruption. Landslides of small volumes, 32 per day on average, are recorded in the Dolomieu crater ... this activity is increased compared to previous months.

Since the end of the last eruption, inflation has resumed between 2,000 m. and the summit, in connection with the source of inflation located towards 1,500 meters under the Dolomieu.

Since March 11, we see the reappearance of apical fumaroles, and an increasing of sulfur gases SO2 and H2S; the H2S increase may result from a disruption of the hydrothermal system, presumably by injections of magmatic fluids and temperature increasing of the system.

An increase of CO2 flow on the rift N120 could indicate a deep pressurizing of the central system.

 

Source : OVPF - Observatoire Volcanologique du Piton de La Fournaise - rapport complet du 25.04.2015
 

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Publié le par Bernard Duyck
Publié dans : #actu
Calbuco 22/04/2015 - eruptive column to Puerto Montt - photo Mabelpau / Twitter

Calbuco 22/04/2015 - eruptive column to Puerto Montt - photo Mabelpau / Twitter

A violent and unexpected eruption occurred at the volcano Calbuco on 04/22/2015 at 18:00, set by the SERNAGEOMIN in red alert.

The eruption of the volcano, dormant for 43 years, justified the evacuation of the population within a radius of 20 km. Two hundred and seventy families are concerned for the moment, but that number could increase in the coming hours. The alert relates to Puerto Montt and Puerto Varas, in the Los Lagos region, and was also given in southern Argentina, Bariloche which may be reached by the ash fall.

The most energetic phase was extended during half past one, with an eruptive column amount to 15,000 meters above the crater. The plume is then opened and headed north and east.

Around 9:55 p.m. local (0:55 GMT), the seismographs recorded a harmonic tremor, suggesting a possible lava emission in the main crater.

On April 23 at 1:00 local (4:00 GMT), a new eruptive impulse marked the volcano, justifying a 10 km exclusion zone.


 

  Calbuco - 22.04.2015 - photo Via IG user jofbroussain / Twitter

Calbuco - 22.04.2015 - photo Via IG user jofbroussain / Twitter

Calbuco - 22.04.2015 -  a serie of pictures from Instagram

Calbuco - 22.04.2015 - a serie of pictures from Instagram

Calbuco 22/04/2015 - photo David Cortes y Francisco Negroniv / AgenciaUno

Calbuco 22/04/2015 - photo David Cortes y Francisco Negroniv / AgenciaUno

The Calbuco, top 2003 meters, is an andesitic stratovolcano lying SW-NE, wearing a summit crater of 400-500 meters wide. Its eruptions were frequent during the Holocene; the largest historical eruption date from 1893 to 1894 with the establishment of a lava dome. The following eruptions have expanded the complex of lava dome in the summit crater. The last eruption of Calbuco dated August, 1972.

 

Sources :

- Sernageomin - Calbuco

- Global Volcanism Program - Calbuco

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Publié le par Bernard Duyck
Publié dans : #actu
Popocatepetl - Overview of 12.19.2014 - The summit crater is occupied by a new dome - photo CENAPRED

Popocatepetl - Overview of 12.19.2014 - The summit crater is occupied by a new dome - photo CENAPRED

Popocatepetl volcano / in the Trans Mexican Volcanic Belt continues the cycle of construction and destruction domes that characterizes the last 20 years.

On December 18th, at 9:14 p.m., an explosion is accompanied by an ash plume rising to 2,000 meters, and incandescent projections on the northern slopes of the cone.

On December 19, an overview of the volcano revealed the presence of a new lava dome in its crater. CENAPRED reports in its latest link that the 20.12, 42 exhalations accompanied by gases, vapors and a little ash were observed, harmonic tremor of low amplitude earthquakes for half an hour, and two volcano-tectonic earthquakes. Nocturnal glow is noted.

The safety zone is 12 km, and aviation alert level remains at 2 / amarillo.

 

Popocatepetl - tremor recorded in December - Doc. CENAPRED

Popocatepetl - tremor recorded in December - Doc. CENAPRED

Popocatepetl - cone and top, with nested craters - Doc. CENAPRED 19/12/2014
Popocatepetl - cone and top, with nested craters - Doc. CENAPRED 19/12/2014

Popocatepetl - cone and top, with nested craters - Doc. CENAPRED 19/12/2014

Vanuatu Geohazards Observatory reported a rapid increase in the activity of Lopevi, based on observations and analysis of early December. The volcano is entered a new eruptive phase. The volcano alert level raised to 1 on a scale of 4 December 15th. The entire island became forbidden area to visitors, and warning declared for the surrounding islands.

The small island of Vanei Vollohulu is formed by the basaltic-andesitic volcano Lopevi. A small summit crater, breached to northwest side contains a cinder cone. The last eruption was some dated 21 April to 14 May 2007 by the GVP.

Sources: GVP / Vanuatu Geohazards Observatory; Vanuatu Daily Post; New Zealand Radio

Lopevi - photo K.Nemeth / Massey Univ.

Lopevi - photo K.Nemeth / Massey Univ.

Lopevi - Map of the flows established in 2001 - from an original map by AJ. Warden Including observations by A-J. Warden and R. Priam (Archive Mines Service); revised and updated by Wallez S. and D. Charley; Drafted by A. Mabonlala. Courtesy of IRD.

Lopevi - Map of the flows established in 2001 - from an original map by AJ. Warden Including observations by A-J. Warden and R. Priam (Archive Mines Service); revised and updated by Wallez S. and D. Charley; Drafted by A. Mabonlala. Courtesy of IRD.

In Cape Verde, Fogo is at its thirtieth day of eruption : the lava flows are stationary in Bangeira but continues to flow from the Monte Saia to Ilheu de Losna, active on two fronts. A cellar, a large vineyard and cassava and bean crops have been destroyed.

Source: Fogo news

 

Fogo - A lava flow advances into cropland around Ihéu de Lorna - photo Geovol / Abraão Vicente Boarboso 12/22/2014

Fogo - A lava flow advances into cropland around Ihéu de Lorna - photo Geovol / Abraão Vicente Boarboso 12/22/2014

 Fogo - lava flow - photo Pascal Blondé, back from the second trip Special Eruption with Adventure and volcanoes.

Fogo - lava flow - photo Pascal Blondé, back from the second trip Special Eruption with Adventure and volcanoes.

  Fogo - 2014.12.22 - photo Marcos Rocha - Asociación Canaria Volcanología

Fogo - 2014.12.22 - photo Marcos Rocha - Asociación Canaria Volcanología

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