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Earth of fire

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

actualites volcaniques

Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques

Uncertainty phase at Katla volcano / Sólheimajökull glacier
Civil Protection recommends to stay away from the front of the glacier Sólheimajökull, due to risk of sudden flooding by meltwater, and the presence of volcanic gases and sulfur degassing of Múlakvísl and Jökulsá rivers.

An increase in the number of small shallow earthquakes may be related to either magmatic movements under Katla, or with an increase in hydrothermal activity and possible adjustments of ice cover associated with an increased melting. At the moment, there are no signs of an eruption.


 

Significant glacial melt in Sólheimajökull - aerial inspection by the Coast Guard and IMO - photo Landhelgisgæsla Íslands / Icelandic Coast Guard.

Significant glacial melt in Sólheimajökull - aerial inspection by the Coast Guard and IMO - photo Landhelgisgæsla Íslands / Icelandic Coast Guard.

Seismicity in the region of Myrdalsjökull - Time and magnitude of earthquake 10 Jul 6:00 GMT / IMO

Seismicity in the region of Myrdalsjökull - Time and magnitude of earthquake 10 Jul 6:00 GMT / IMO

To the Stromboli, a sudden outpouring of lava occurred on July 7 with an overflow on the top of the Sciara del Fuoco. A surge of magma caused a partial collapse of the hornito NE (N2) at 5:30 accompanied by an avalanche.

The activity at Stromboli is fluctuente, with peaks at intervals of 2-3 days. In the evening of 09 and the morning of 10.07, two new lava overflows fueled a flow in Sciara del Fuoco.

Stromboli - lava views thermal webcam 07 and 10/07/2014 - Images INGV CataniaStromboli - lava views thermal webcam 07 and 10/07/2014 - Images INGV Catania

Stromboli - lava views thermal webcam 07 and 10/07/2014 - Images INGV Catania

On Mount Etna, still no comment from INGV for the opening of a new mouth to the base of the crater northeast.

Recent pictures by Alpine guides show an hornito, located at 3,100 m., characterized by the spattering that feeds a small lava flow in the Valle del Leone.

Etna - hornito at the base of the northeast crater - photo Gio Giusa / Biagio Ragonese (Guida Alpina dell Etna)

Etna - hornito at the base of the northeast crater - photo Gio Giusa / Biagio Ragonese (Guida Alpina dell Etna)

Etna - The hornito at the base of the northeast crater is feeding a small lava flow -  photo Gio Giusa / Biagio Ragonese (Guida Alpina dell Etna)

Etna - The hornito at the base of the northeast crater is feeding a small lava flow - photo Gio Giusa / Biagio Ragonese (Guida Alpina dell Etna)

News from Tolbachik / Kamchatka:

A report by Alexander Belousov on the exploration of a lava tunnel, barely cooled after the eruption in 2013 : He describes the presence of stalactites and stalagmites formed by minerals still being identified.
"On the surface, it looks like ice. They are half transparent, slightly whitish, sometimes yellowish. Size is sufficiently large: more than half a meter long and five centimeters in diameter. However we do not know from which minerals are they formed. We assume that these are metal chlorides. Currently we are studying their composition. "


http://volkstat.ru/news.php?subaction=showfull&id=1404748400&ucat=38

Results are expected within two weeks.

 Tolbachik - lava tunnel - photo Volkstat.ru

Tolbachik - lava tunnel - photo Volkstat.ru

Always in Kamchatka, the Shiveluch emitted a plume, rising to more than 10 km on July 8, according to ITAR / TASS.
According KVERT / KSCNET, there are risks for air trafic ... the alarm code remains orange.

To the Zupanovsky,
the eruption continues, with a plume of gas and ash up to 6 km. height, and drifting eastward. (satellite detection by ESA)
 

Shiveluch - photo © Volcanology and Seismology Institute of Russia's Far Eastern branch of the Academy of Sciences / ITAR-TASS 08.07.2014.

Shiveluch - photo © Volcanology and Seismology Institute of Russia's Far Eastern branch of the Academy of Sciences / ITAR-TASS 08.07.2014.

At Kilauea / Hawaii:

The lava flow Kahauale'a 2
from the crater Pu'u O'o ceased production after a breakout on 06/27/2014. Lavas issued on the northeast flank of the Pu'u O'o formed small streams that are superimposed and gave birth to a new little shield. It has a small pool of lava on the top.
The latest comparative photos of the HVO webcam show a clear change in the horizon.

The area remains inaccessible because of the danger of eruption, collapse and potentially lethal concentrations of sulfur dioxide in an area of ​​1,000 meters downwind. Active flows in the forest area can also produce methane blasts, capable of propelling into the air, rocks and debris.

 

Kilauea / Pu'u O'o - Lava flows on 30.06.2014 - photos HVO

Kilauea / Pu'u O'o - Lava flows on 30.06.2014 - photos HVO

Kilauea / Pu'u O'o - change in the skyline between 26.06 and 06.07.2014 - photo HVO

Kilauea / Pu'u O'o - change in the skyline between 26.06 and 06.07.2014 - photo HVO

To the Sinabung, the lava lobe (secondary) of the dome-flow has been the subject of further collapse that generated a small pyroclastic flow that has not reached the base of the cone, 07.10.2014 at 10:26 local.
 

Sinabung - pyroclastic flow from 07/10/2014 - webcam VSI

Sinabung - pyroclastic flow from 07/10/2014 - webcam VSI

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Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques

After destroying Plymouth and making uninhabitable a third of the island of Montserrat, the Soufrière Hills Volcano will give him a "clean" source of energy.

Montserrat, the "Emerald of the Caribbean" is a martyr island : massively destroyed by Hurricane Hugo in 1989, she saw her volcano enter in a new eruption destructive cycle in 1995. Following the burial of Plymouth in 1997, more.of half  the population decided to emigrate.

 SoufriereHillsVolcano - 1995 eruption - photo NSF - B.Voight

SoufriereHillsVolcano - 1995 eruption - photo NSF - B.Voight

 Montserrat -  Plymouth, after eruption of 12/07/97 - photo Hoblitt RP / USGS

Montserrat - Plymouth, after eruption of 12/07/97 - photo Hoblitt RP / USGS

Due to the high cost of drilling and looking uncertain results of this type of operation, the geothermal potential of the island-volcano had not been emphasized until recently.

New techniques have been employed, from 2009, at the request of local government, to understand more clearly the structure of the basement and choose a potential drilling site.
Magnetotelluric techniques use signals emitted during storms and charged particles ejected during solar flares for penetration of the basement. Seismic tomography uses the responses to pressure waves created by an explosion to generate images of subsurface rocks.

Among the selected sites, an area protected from pyroclastic flows, the largest hazard in case of eruption of Soufriere Hills, was located in a graben between St George and Garibaldi Hills, where a layer of altered clay covers a potential geothermal system.

Conceptual model based on survey data to home in on best site for drilling a well. Ryan, Peacock, Shalev, Rugis (2013), Montserrat geothermal system: a 3D conceptual model, Geophys. Res. Lett. doi: 10.1002/grl.50489.

Conceptual model based on survey data to home in on best site for drilling a well. Ryan, Peacock, Shalev, Rugis (2013), Montserrat geothermal system: a 3D conceptual model, Geophys. Res. Lett. doi: 10.1002/grl.50489.

To the left, the alert level and exclusion areas into force in July 2014 / doc. MVO - right, simplified map of the southern part of the island of Montserrat and location of drilling areas - doc. MTU - click on the maps to enlargeTo the left, the alert level and exclusion areas into force in July 2014 / doc. MVO - right, simplified map of the southern part of the island of Montserrat and location of drilling areas - doc. MTU - click on the maps to enlarge

To the left, the alert level and exclusion areas into force in July 2014 / doc. MVO - right, simplified map of the southern part of the island of Montserrat and location of drilling areas - doc. MTU - click on the maps to enlarge

Between March and September 2013, the Iceland Drilling Company currently drilled two exploration wells, respectively 2,300 and 2,900 meters, reaching temperatures above 260 ° C.  These preliminary results suggest an energy source amply sufficient for the population remaining on Montserrat.

A geothermal power plant could release Montserrat of its current dependence versus its use of very expensive diesel-powered generators.

Finally, a new positive for the people of this island paradise once.


 

Montserrat - geothermal drilling platform - photo Carib Journal

Montserrat - geothermal drilling platform - photo Carib Journal

All the volcanic islands of the Lesser Antilles have similar geological settings and therefore the same geothermal potential. For now, only the Guadeloupe uses geothermal energy for the production of electricity. St Kitts and Nevis is also promising to make holes ... the region should therefore be free of economic constraints related to the volatility of oil prices, and gain an energetic independence.

 

Sources :

- Caribbean island buried by eruption goes green with volcano power – by Graham Alexander Ryan Research Fellow at University of Auckland

- Preliminary results of deep geothermal drilling and testing on the Island of Montserrat - Paul Brophy & al. - link

- MVO * Montserrat Volcano Observatory - link

By Geoff Mackley

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Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques

According to the JMA - Japan Meteorological Agency, the Kusatsu-Shirane San, located on the island of Honshu near the volcano Asama, present since March an elevated temperature and deformation, located north of the crater Mizugama . This activity always keeps the end of June (confirmed by the GVP). The alert level remains at 2 on a scale of 5. A possible eruption should be small in magnitude.
 

Kusatsu-Shiranesan - photo 2008 - Courtesy of Flickr user rangaku1976.

Kusatsu-Shiranesan - photo 2008 - Courtesy of Flickr user rangaku1976.

Kusatsu-Shirane San is an andesitic to dacitic volcano, that is built in three eruptive periods beginning in early or mid-Pleistocene. A pyroclastic flow, called Ochi, of Pleistocene, is responsible of the production of ignimbrites covering the slopes east, south and west soud. The latest eruptive period began here 14,000 years.

The summit of the volcano consists of a series of overlapping pyroclastic cones, and three lakes occupying the craters Karagama, Yugama, Mizugama.

The Yugama, meaning "boiling pot", is a central crater lake, 300 meters in diameter and 30 m deep, with an emerald green water, extremely acidic (pH around 1) . Its water never freeze despite elevation, due to the presence of hot sulfur springs.

Fumaroles and hot springs dot the flanks of the volcano, and are responsible for acidification of the rivers draining the water. Sulfur was exploited there during the 19th and 20th centuries.

 

Kusatsu-Shiranesan - Acid lake Yugama - photo 663 Highland

Kusatsu-Shiranesan - Acid lake Yugama - photo 663 Highland

Left, location of Kusatsu-Shiransan, 150 km from Tokyo - JMA map - right,  the top of Kusatsu-Shiranesan and its three crater lakes - circles indicate areas of fumaroles - crosses are position of the active vents from the eruption 1982 -. Doc. JMA / GVPLeft, location of Kusatsu-Shiransan, 150 km from Tokyo - JMA map - right,  the top of Kusatsu-Shiranesan and its three crater lakes - circles indicate areas of fumaroles - crosses are position of the active vents from the eruption 1982 -. Doc. JMA / GVP

Left, location of Kusatsu-Shiransan, 150 km from Tokyo - JMA map - right, the top of Kusatsu-Shiranesan and its three crater lakes - circles indicate areas of fumaroles - crosses are position of the active vents from the eruption 1982 -. Doc. JMA / GVP

All historical eruptions recorded are phreatic explosions, headquartered in acidic lakes or on their edges.

Five phreatic eruptions mark the period 1982-1983; after the first of them, the 26.10.1982, the temperature of the lake Yugama reached 55.5 ° C.

A small eruption there occurred Jan. 6, 1989.

In February 1996, discoloration of water marks the NW part of the lake, in conjunction with a sudden discharge of fluid or a minor hydrothermal explosion.

 

Kusatsu-Shiranesan - photo 663 Highland

Kusatsu-Shiranesan - photo 663 Highland

Kusatsu - South Side of Yubatake - Wood features of the upper pool to cool the hot springs and collect sulfur powder. - Photo Muikabochi

Kusatsu - South Side of Yubatake - Wood features of the upper pool to cool the hot springs and collect sulfur powder. - Photo Muikabochi

Kusatsu city, at the foot southeast of Kusatsu-Shirane-san, has 18 Onsen / bathhouses, each known for a different effect and powered by individual sources. The most famous are the Yubatake and Netsu-no-yu.

 

Sources :

- Global Volcanism Program - Weekly report

- Global Volcanism Program - Kusatsu-Shiranesan

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Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques
Reunion - eruption of Piton de la Fournaise - 21/06/2014 - the chopper right gives the scale - photo Richard Bouhet / AFP

Reunion - eruption of Piton de la Fournaise - 21/06/2014 - the chopper right gives the scale - photo Richard Bouhet / AFP

The eruption continues at Piton de La Fournaise ... below, verbatim report of OVPF of 21.06.2014 / 2:30 p.m. LT:

Location of eruptive fissures on the flank of the summit cone ESE between the crater and the Maillard small plateau at about 2300 m altitude.

Recognition by helicopter helped in the morning to view the phenomenology of the eruption:

    
1 / One crack on the three visible from the camera of Piton Bert was active in 8:30 (TL). It is characterized by a lack of dynamism with small fountains.
    
2 / Only two cracks were identified. Because of bad weather when flying from the top because two or three cracks observed on the camera are actually contiguous.
    
3 / The crack of December 2009, the top radial and inactive crack emit a lot of steam.
    
4 / The active crack  built a small spatter wall and contains the bulk of the casting
    
5 / the lava flow is divided at the outlet of the cracking in two parallel main branches, which stretch over 1.5 km.
    
6 / At 1990 m altitude, at the crater Langlois, the two ​​lava tongues distinctly separate. One pass from the east and stops after about 250 meters. The second, skirting the eastern and southern Langlois crater stretches for about 500 meters.
    
7 / sampling of lava, temperature and gas in the volcanic plume 
measurements has been made.
    
8 / A plume of very dilute of SO2 stretches along the relief skirting the volcano to be transported northwards by the prevailing winds.

In OVPF the Tremor has decreased in the early hours of the rash appears and is currently maintaining.

 

Topographic map of Piton de la Fournaise - location of craters Dolomieu and Langlois

Topographic map of Piton de la Fournaise - location of craters Dolomieu and Langlois

Piton de la Fournaise - one of the lava flows - the volcanologist in the foreground allows to estimate the width - photo Richard Bouhet / AFP

Piton de la Fournaise - one of the lava flows - the volcanologist in the foreground allows to estimate the width - photo Richard Bouhet / AFP

Sources :

- OVPF - Observatoire Volcanologique du Piton de La Fournaise - lien

- Préfecture de la région Réunion - Piton de la Fournaise : alerte 2-2 éruption en cours dans l’enclos - Point de situation à 17h00 - lien

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Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques
Semisopochnoi in the Aleutian arc - photo Roger Clifford / AVO - 2012.

Semisopochnoi in the Aleutian arc - photo Roger Clifford / AVO - 2012.

A seismic swarm began on volcano Semisopochnoi, June 9, 2014 at 18h UTC. Its increase on June 12, around 20h UTC, motivated the AVO - Alaska Volcano Observatory, to raise alert levels: alert aviation Yellow - volcanic alert Advisory. No eruptive activity is reported at this time.

This volcano is located on the youngest volcanic island in the western Aleutians; although remote and uninhabited, the island which houses the Semisopchnoi is monitored by a network of five operational seismic stations and satellite.

 

Location Semisopochnoi - Map Schaefer, Janet / AVO

Location Semisopochnoi - Map Schaefer, Janet / AVO

This volcano is dominated by a caldera 8 km. in diameter, dated early Holocene, which contains a small lake, the Fenner lake, and many craters and post-caldera cones.

Its last eruption in 1987, probably located at Sugarloaf Peak, on the south coast of the island. Mount Cerberus, a set of three pointed cones occupies the southwestern part of the caldera.

 

Topographic map Semisopochnoi - doc. USGS - AVO

Topographic map Semisopochnoi - doc. USGS - AVO

Sources : AVO - Alaska Volcano Observatory

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Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques

To the Kamchatka, the KVERT announces an explosive eruption of Zhupanovsky, starting June 6, 2014. It was accompanied by a plume of ash and gas rising to over 6,000 meters depending on the Tokyo VAAC. No satellite data since the cloud cover. The aviation alert level rose to yellow.

Moderate explosions continued, requiring vigilance in air traffic.

 

Zhupanovsky 06/07/2014 - photo KGBU "natural park" volcanoes of Kamchatka "Nalychevo Nature park

Zhupanovsky 06/07/2014 - photo KGBU "natural park" volcanoes of Kamchatka "Nalychevo Nature park

Guatemalan press, informed by a volcanologist of INSIVUMEH, tells us a lahar from Santiaguito destroyed two seismic observatory facilities, on 5 June. Santiaguito ash were mobilized by heavy rains in recent days, related to a tropical storm.

On the video, shot at 20 km from the volcano, at the Castillo Armas bridge, you can see the river Nima smoking ! It is therefore a "hot lahar".

 

Video of the hot lahar from Santiaguito, by CONRED

Fuego make no exception: a Twitt of INSIVUMEH reported the issuance of a column of gray color amount to 4200-4400 meters before drifting W-NW on 6-19 km.
 

Fuego - 07/06/2014 - photo INSIVUMEH via Twitter

Fuego - 07/06/2014 - photo INSIVUMEH via Twitter

In the Ogasawara Islands, the situation did not change much at Nishino-shima.

An overview of the new volcano 03.06, shows three craters, craters qualified "North, South and new crater", two assets. A plume overcomes the island of about 1,000 meters.

Recent photos show the lava flows are still at sea, generating steam plumes, probably fed by lava tubes.

Discoloration of seawater is observed on the coast of the ancient volcano, which is nibble each day a little more.


 

Nishino-shima - Double plume and discoloration of the sea - overview of 06/03/2014 / doc GSJ - AIST

Nishino-shima - Double plume and discoloration of the sea - overview of 06/03/2014 / doc GSJ - AIST

Nishino-shima - the lava is conducted in a tube - overview of 03/06/2014 / doc GSJ - AIST

Nishino-shima - the lava is conducted in a tube - overview of 03/06/2014 / doc GSJ - AIST

Nishino-shima - lava tubes and ocean entry - lava from the eruption in progress covers a large part of the original volcano - overview of 06/03/2014 / doc GSJ - AIST

Nishino-shima - lava tubes and ocean entry - lava from the eruption in progress covers a large part of the original volcano - overview of 06/03/2014 / doc GSJ - AIST

The Kusatsu-shirane - photo 663highland

The Kusatsu-shirane - photo 663highland

The Japan time relays an alert rise level of Kusatsu-shirane volcano, June 3, 2014, and a risk of a possible eruption of small-scale.

This volcano, andesitic to dacitic, located north of Asama, consists of a series of pyroclastic cones overlap and three crater lakes. Its last eruption was in 1983 (GVP)

Finally, a beautiful photo of Popocatépetl, that deserves its name in Nahuatl: "The smoking mountain "

 

Popocatépetl - photo LBZ / 06/06/2014

Popocatépetl - photo LBZ / 06/06/2014

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Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques

Dr. Jourdan and his team, from Curtin University , recently demonstrated the influence of volcanic eruptions of Kalkarindji province , in northern Australia , on the climate causing the first mass extinction on Earth.
 

Extinctions intensity -  influence of meteorite impacts and LIP 's ( Large Igneous Provinces ) .

Extinctions intensity - influence of meteorite impacts and LIP 's ( Large Igneous Provinces ) .

Using dating techniques based on radioactivity has precisely dated the eruptions of this igneous province , between 510-511 Ma. Two million square kilometers were covered with lava ... massive emissions of sulfur dioxide have be measured by a depletion of SO2 in volcanic rocks of this province.

The fact that the Cambrian extinctions , affecting more than 50% of complex multicellular organisms , including the famous trilobites, brachiopods and conodonts, are related to abrupt climate change and depletion of oxygen in the oceans , was known ... but the mechanisms to the origin of these changes are not yet specified .

Rapid climate oscillations produced by these major volcanic eruptions cause adjustment difficulties for many species .

 

Trilobite fossil

Trilobite fossil

According to Dr. Jourdan , these studies can help us understand how the climate , oceans and ecosystems were affected in the past, and hence better understand the biological and climatic effects in the long term due to the massive injection of gas into the atmosphere by our modern society .

The Kalkarindji CFBP ( Continental Flood Basalt Province) , located in the northern territories of Australia, is a large igneous provinces among the least known and the oldest to have been active in the Phanerozoic . The basalts are slightly distorted and petrology exceptionally preserved despite their age .

 

Australian 's LIP (Large Igneous Province) - doc.Geosciences Autralia 2010 (legend by following this link : http://www.largeigneousprovinces.org/10oct )

Australian 's LIP (Large Igneous Province) - doc.Geosciences Autralia 2010 (legend by following this link : http://www.largeigneousprovinces.org/10oct )

Sources :

- High-precision dating of the Kalkarindji large igneous province, Australia, and synchrony with the Early–Middle Cambrian (Stage 4–5) extinction  - by F.Jourdan & al.- link

- Curtin University - Australia’s deadly eruptions the reason for the first mass extinction - link

- Large Igneous Provinces Commission - A review of Kalkarindji - the oldest Phanerozoic flood basalt province - link

- The earliest trilobites - link

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Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques

Analysis of pottery for household and ceremonial use from Mayan cities, located on the Caribbean side of Central America, discloses the use of a mixture of limestone and volcanic ash, facilitating the cook of these ceramics. This approach is characteristic of the Late Classic period, between the years 600 and 900.

Like thousands of Mayan lived in big cities like Tikal and El Pilar, potters had to handle tons of volcanic ash every year ... but what is their origin?

No volcano is present in the eastern part of Central America!

 

Maya ceremonial vase - Terminal Classic period (600-900) - Copan / Honduras - photo Durova

Maya ceremonial vase - Terminal Classic period (600-900) - Copan / Honduras - photo Durova

Inefficient practices transportation of the Mayas moving towards a local resource, rather than a long-distance transport of these ashes. The option of a local volcanic ash involve thereof an air transport model. In addition, microscopic examination of pottery reveals a recent volcanic source.

Kevin Coffey, from the University of California at Los Angeles, set, among 11 volcanoes potentially liable, the Salvadoran Ilopango volcano, whose the devastating eruption, of VEI 6 +, destroyed the nearby cities  during the 5th century (450 + / - 30 years - GVP), and covered with ashes Central America. At the time, the centers of civilization of the Mayans moved from Salvador northward and to Guatemala.

 

Ilopango caldera and / Lake Salvador - photo credit NASA

Ilopango caldera and / Lake Salvador - photo credit NASA

Lago Ilopango  - photo Mateosal

Lago Ilopango - photo Mateosal

Ilopango caldera and its lake:

Near the capital of El Salvador, the Ilopango caldera, 8 x 11km wide, and surrounded by tall walls of 150 to 500 meters height,  is occupied by a large lake.

Four major dacito-rhyolitic eruptions produced, between the late Pleistocene and Holocene, deposits of ash and pyroclastic flows that have carpeted much of El Salvador. The last caldera collapse is related to the eruption TBJ - Terra Blanca Joven - in 5th century.

Post-caldera eruptions have formed a series of lava domes within the lake and its shores. Quemadas islands, a group of central islets, show a dome largely submerged, following the eruption of Ilopanga in 1879-80.

 

Ilopango -  TBJ - Tierra Blanca Joven - formation, exposed in a quarry near Cojutepeque, 9 km.of the issuing caldera, is dated of 5th century - G.Kysar Photo / Smithsonian.

Ilopango - TBJ - Tierra Blanca Joven - formation, exposed in a quarry near Cojutepeque, 9 km.of the issuing caldera, is dated of 5th century - G.Kysar Photo / Smithsonian.

Drawing of the Ilopango caldera - doc in "Los Volcanes Activos de Guatemala y El Salvador" by Helmut Meyer-Abich 1956.

Drawing of the Ilopango caldera - doc in "Los Volcanes Activos de Guatemala y El Salvador" by Helmut Meyer-Abich 1956.

But the mystery remains still unsolved !

Teams of UCLA finally flunked the Ilopango. The study of zircon crystals present in the ash from pottery suggest older eruptions and deposits, and different chemical signatures following the fragments examined point an origin of the ash involving at least two different volcanoes.

To be continued ...

 

Sources :

- Live Science - Volcanic Evidence Opens New Maya Mystery - link

- Global Volcanism Program - Ilopango

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Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques
A scientific campaign to analyze the tectonic and subvolcanic crustal structures, upon which the Etnais based, will be conducted in June and July. It will be an official presentation in Catania today.

Sixty researchers from various institutions will be involved in this research, conducted within the framework of two European projects , the " Medsuv " - Mediterranean supersite volcanoes - and " Eurofleets 2" projects.

" Tomo -Etna " , a campaign to study under Etna.

The analysis will be done through active seismic techniques, the waves generated by compressed air , and passive , through the natural earthquakes recording .

For marine exploration, various naval units contribute to this activity, the Spanish oceanographic research vessel " Sarmiento de Gamboa ", the hydrographic Greek ship "Aegea " ,and Italian ships.

The acquisition of seismic signals will be through the permanent seismic network of the INGV , supplemented by a temporary network of 100 stations arranged on Etna and the surrounding provinces of Catania , Messina and Syracuse . At sea, a network of stations OBS / H , Ocean Bottom Seismometers , ranging from near Etna to the Aeolian islands .

 

" Tomo -Etna " - left, location of seismic stations - right , trips planned for oceanographic studies - doc . INGV Catania / via iEtna

" Tomo -Etna " - left, location of seismic stations - right , trips planned for oceanographic studies - doc . INGV Catania / via iEtna

The study of magnetic and gravity anomalies will be during cruises, through magnetometers and gravimeters .

The data collected will help to establish a precise tomography, and may shed a new light on the process of magma ascent of Etna.



 

The projected tomography make improvements to the current tectonic pattern. - Doc. Volcanism in / H.U.Schmincke .

The projected tomography make improvements to the current tectonic pattern. - Doc. Volcanism in / H.U.Schmincke .

Sources :

- INGV Catania - Alle redici dell'Etna - communication à la Stampa - link

- iEtna - “Tomo – Etna”: Grande progetto Ingv Catania per studiare le radici del vulcano siciliano. - link

- Volcanism - par H.U.Schmincke

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Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques
Chaparrastique / San Miguel - photo MARN 01/01/2014

Chaparrastique / San Miguel - photo MARN 01/01/2014

In Salvador, the Chaparrastique / San Miguel , the probability of an eruption in the next days increased.

MARN indicates an increase in internal vibrations ( RSAM ), an increase in the frequency and magnitude of gas impulses, rumblings in the crater , small explosions accompanied by fine ash falls ... rich in juvenile material !

The eruption could issue more material than in the last activity, on 12.29.2013 , and may,  in the light of the micro- seismicity, concern either the crater or the northern flank of the volcano.

 

Increased internal vibrations Chaparrastique between 01.12.2013 and 05.19.2014 - Doc. SNET / MARN

Increased internal vibrations Chaparrastique between 01.12.2013 and 05.19.2014 - Doc. SNET / MARN

Microseismic epicenters between 27.01 and 05.19.2014 : 279 earthquakes not felt , M 0,4 -1.9 were recorded during this period on the northern flank of the volcano - Doc. SNET / MARN

Microseismic epicenters between 27.01 and 05.19.2014 : 279 earthquakes not felt , M 0,4 -1.9 were recorded during this period on the northern flank of the volcano - Doc. SNET / MARN

The authorities have planned, at a meeting on 19 May , a precautionary evacuation for 72 hours of the families most affected by a coming eruption ... however few families willing to leave their homes.

La Prensa Grafica , a Salvadoran daily ,  indicates on 20.05 that only 12 adults and 15 children were sheltered , ... which is little.

The mayor of San Miguel reported on Twitter that sent trucks to evacuate returned empty. The Reuters news agency reported against by the evacuation of over 1,000 people.
 

Some evacuees boarded onto trucks - photo Milton Flores / LPG / 05/19/2014

Some evacuees boarded onto trucks - photo Milton Flores / LPG / 05/19/2014

Sources :

- SNET/ MARN (El Ministerio de Medio Ambiente y Recursos Naturales) – rapport du 190.05.2014 - link

- Presse locale : Diario Latino - La Prensa Grafica - El Salvador.com

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