Overblog
Suivre ce blog Administration + Créer mon blog

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

The eruption of ONTAKESAN seems, following Shigeo Aramaki a volcanologist, to be an eruption of phreatic type, without ruling out a phreatomagmatic phenomenon as the ash analysis is not complete. The relatively violent explosion, limited in time, and the white and black plume on the latest photos are evidence for the phreatic type, usual on this volcano since thousands of years.

Ontake - 09/27/2014 eruption - impressive plumes rise above the volcano - photo AP / Kyodo News

Ontake - 09/27/2014 eruption - impressive plumes rise above the volcano - photo AP / Kyodo News

Ontake - 09/27/2014 eruption - the ash cloud engulfs the slopes of the volcano, partially in autumn colors - photo of an anonymous / via Kyodo News

Ontake - 09/27/2014 eruption - the ash cloud engulfs the slopes of the volcano, partially in autumn colors - photo of an anonymous / via Kyodo News

Ontake 09/27/2014 - white and black turbulent plumes emitted at the eruptive vent - photo AP / Kyodo News

Ontake 09/27/2014 - white and black turbulent plumes emitted at the eruptive vent - photo AP / Kyodo News

The video posted yesterday shows hikers fleeing before the eruption before getting cover in the dust cloud, which plunged into total darkness for several minutes. A reporter from NHK, M.Oguro, says that he and his team had to use their headlamp to find the lodge.

The owner of this mountain lodge near the top reports that the ash layer was 50 cm. Of falling ash are reported on the prefectures of Nagano, Gifu and Yamanashi.

Ontake - buildings near the top are covered with a thick layer of ash - Photo AP / Kyodo News

Ontake - buildings near the top are covered with a thick layer of ash - Photo AP / Kyodo News

At last report yesterday, the eruption caused the death of a woman, made ​​thirty seriously wounded, 16 people unconscious.
Over forty people waiting to be evacuated by the army, while 200 walkers began the descent of the Ontake in the ash left by the eruption, on their own.

The balance sheet has seriously weighed this morning, according Associeted Press, 9/28/2014  / 2:27, more than thirty bodies were found unconscious and considered as dead near the summit of the volcano. They were described as "not breathing and heart stopped", pending autopsy confirmed the cause of death.


 

Descente in the ash of  the majority of hikers in the day on Saturday - left picture www.toledoblade.com pic.twitter.com-cbY57gqkBP - right, AP photo / Kyodo news - one click to enlarge. Descente in the ash of  the majority of hikers in the day on Saturday - left picture www.toledoblade.com pic.twitter.com-cbY57gqkBP - right, AP photo / Kyodo news - one click to enlarge.

Descente in the ash of the majority of hikers in the day on Saturday - left picture www.toledoblade.com pic.twitter.com-cbY57gqkBP - right, AP photo / Kyodo news - one click to enlarge.

The eruption of 1979-1980 has many similarities.

The first historical eruption began listed 28 octobre1979 after only one episode of tremor and long-term without initial explosion recorded.

Ash emissions have followed up to 14h, at which time an ash plume rose to 1,000 meters. A deposit of ash of 1.5 meters was recorded near the top, while the sides are covered only bu a few tens of centimeters. The activity then declined with vapor emissions on 29.10, and other emissions of varying intensity until mid-November.

Many vents made ​​active during the eruption, in an area of ​​500 meters long oriented NW-SE near the top. Up to 10 small craters have been spotted during an aerial inspection. No fumaroles were present in this area of new vents before the eruption.

1979 - Aerial view of the top of the Jigoku-dani, taken from the south - the gray plume containing ash - photo Chubu color

1979 - Aerial view of the top of the Jigoku-dani, taken from the south - the gray plume containing ash - photo Chubu color

1979 - fumerolienne intense activity marks the top of the Jigoku-dani (valley) - phot Chubu color

1979 - fumerolienne intense activity marks the top of the Jigoku-dani (valley) - phot Chubu color

Sources:

- Médias locaux, dont Japan Times - Kyodo news

- Volcanoes of Japan - Quaternary volcanoes - Ontake san

Lire la suite

Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques

To Holuhraun, the eruption continues at the same pace as the previous day. The lava field continues to grow and reached an area of ​​38 square kilometers (estimated on 21.09), powered by a high lava speed of 250 to 350 / sec. The total volume of lava emitted is close to 500 million m³.

On 22 September, the University of Iceland published a photo showing a break on the north edge of the lava field, under the weight of the lava.

Holuhraun - 20/09/2014 lava flow view satellite EO-1 / Ali NASA

Holuhraun - 20/09/2014 lava flow view satellite EO-1 / Ali NASA

Holuhraun - lava outbreak on the north edge of the flow 22/09/2014 - photo IES

Holuhraun - lava outbreak on the north edge of the flow 22/09/2014 - photo IES

 Map of changes in flows, with surface indications on 23/09/2014 - Doc. IES

Map of changes in flows, with surface indications on 23/09/2014 - Doc. IES

New branches appeared on the lava flow, 09.22.2014 - photo IES

New branches appeared on the lava flow, 09.22.2014 - photo IES

Subsidence that marks the caldera of Bárðarbunga continues unabated too, and depression reached since its inception a depth of 27-28 meters, and an estimated volume on 23.09 of 0.6 cubic kilometers. (volume of the lava issued is 0.5 km³)

Ten earthquakes were recorded between midnight and 7am., on 25.09. The largest of the 25.09 / 8:14 measuring a magnitude of 5.2.

 

Subsidence that marks the caldera Bárðarbunga 09/25/2014

Subsidence that marks the caldera Bárðarbunga 09/25/2014

GPS measurements reveal movements similar surface for the past two weeks.
 

Movement of GPS stations on Holuhraun / Bárðarbunga on 25/09/2014 - doc IMO

Movement of GPS stations on Holuhraun / Bárðarbunga on 25/09/2014 - doc IMO

Pollution by SO2 and fine particles is locally expected on 25.09 north of Iceland, today against the east and southeast.

The indices were measured in recent days for SOat 200-600 kg / sec. and CO2 at 250-700 kg / sec.Total gases is estimated minimum 10-20000 tonnes / day, according Þorsteinn Jóhannsson, from the Icelandic Environmental Agency.

Toxicity requires the wearing of masks in the wind, in the area of the eruption, where birds were found dead.

Indices of air quality on Brittany / France indicate a significant amount of fine particles for Wednesday and Thursday in conjunction with the release of the eruption in the atmosphere, confirmed by Air Breizh direction.

The ATMO index used for these assessments is determined based on four pollutants: SO2, NO2, ozone and fine particles less than 10 μ (PM10) / also issued by other sources that the volcanic ... on 25.09, the Atmo index was 8 on a scale of 10 to Brest, St Brieuc, Rennes, Lorient and Vannes.

Simulation of the movement of fine particles on 09/22/2014 over the British Isles, Germany, Holland, Belgium, and northern France - map Der Spiegel on line

Simulation of the movement of fine particles on 09/22/2014 over the British Isles, Germany, Holland, Belgium, and northern France - map Der Spiegel on line

Rear projection of fine particulate 09/24/2014, with impact on Brittany / France  - Air Breizh map

Rear projection of fine particulate 09/24/2014, with impact on Brittany / France - Air Breizh map

Some interesting pictures of the crack, active and inactive part, with a photogenic cone ... and the lava flow in Jökulsá á Fjöllum.

Craters south of  the Holuhraun fissure and in the background, the white plume erupting from the activecrater Baugur - Photo: Vedurstofa Islands 24/09/2014

Craters south of the Holuhraun fissure and in the background, the white plume erupting from the activecrater Baugur - Photo: Vedurstofa Islands 24/09/2014

 The lava flow in Jökulsá á Fjöllum. - Photo 24.09.02014 IMO

The lava flow in Jökulsá á Fjöllum. - Photo 24.09.02014 IMO

Sources :

- IMO, IES, Iceland Review

- Der Spiegel, Air Breizh et French medias.

Lire la suite

Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques
Mayon - the dome- flow at the top of the volcano 23.09.2014 - photo Dost Pagasa

Mayon - the dome- flow at the top of the volcano 23.09.2014 - photo Dost Pagasa

Mayon - another view of the dome-flow and a light vapor plume 23/09/2014 - photo Dost Pagasa

Mayon - another view of the dome-flow and a light vapor plume 23/09/2014 - photo Dost Pagasa

The situation is gradually changing on Mayon volcano, located on the island of Luzon in the Philippine archipelago.

Since two months, the volcano presented short inflationary phases, suggesting a pulsing climb of magma. In August, the SO2 levels were measured up ... raising the alert level to 2 by the Phivolcs, accompanied by a 6-km exclusion area.

The alert was raised to 3 (of 5) on September 15, following the increase of seismicity and incandescent rocks falling on the upper flanks southeast. The presence of low-frequency earthquakes indicate rising magma in the volcano, the recent observation of a lava dome and its partial collapse generating drops of incandescent rocks visible at night.

 

Night glow at Mayon le2014.09.16 / 3h 19 am - photo J.Manzanilla / Legazpy city

Night glow at Mayon le2014.09.16 / 3h 19 am - photo J.Manzanilla / Legazpy city

Mayon on 09/23/2014 - Photo in natural light versus thermal image of the dome-flow - photo Mahar Lagmay / pic.twitter.com/khpMqRyTN5

Mayon on 09/23/2014 - Photo in natural light versus thermal image of the dome-flow - photo Mahar Lagmay / pic.twitter.com/khpMqRyTN5

The exclusion zone is 6 km around the summit, and extended to 7 km to the southeast area, the most exposed to possible pyroclastic flows.

The evacuation of residents from the danger zone is underway ... they are being targeting 10,000 families who live there.

Map of exclusion edited by Phivolcs zones - zone 6 km ring road, extended a precautionary 7 km SE of the volcano - lava eruptions in 1993 - doc in GVP

Map of exclusion edited by Phivolcs zones - zone 6 km ring road, extended a precautionary 7 km SE of the volcano - lava eruptions in 1993 - doc in GVP

Danger areas in case of pyroclastic flows - Doc. Phivolcs 04.2003

Danger areas in case of pyroclastic flows - Doc. Phivolcs 04.2003

Topographic shaded map - 2011 map courtesy of United Nations Institute for Training and Research's (UNITAR's) Operational Satellite Applications Programme (UNOSAT).

Topographic shaded map - 2011 map courtesy of United Nations Institute for Training and Research's (UNITAR's) Operational Satellite Applications Programme (UNOSAT).

Evacuation of people from the exclusion zone by the military trucks 9/18/2014 - Photo AFP

Evacuation of people from the exclusion zone by the military trucks 9/18/2014 - Photo AFP

Sources :

- Global Volcanism Program - Mayon

- Phivolcs - rapports - link

- Ambassade US / Philippines - Increased activity at the Mayon volcano - link

 

You can, in addition to daily articles, find news briefs on volcanoes via Twitter - or Facebook / groupes Volcanoes

Lire la suite

Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques
Holuhraun - Optical effects of eruptive gases.

Volcanic emissions affect the climate, and are also responsible for optical phenomena: the veil of gases, mainly sulfur dioxide, can change the colors of the sky at sunset.

Professor Zerefos gave a key to this change, in an article in the Journal of the EuropeanGeosciences Union: "In coloring sunsets, this is the way the brain perceives green and red which contains important information on the environment. "

The painters of the 19th century have reproduced these specific colors without understanding the cause. Among them, William Turner, known for his mastery of color, was alive during three major eruptions, that of Tambora in Indonesia in 1815 (VEI 7), that of Babuyan Claro in the Philippines in 1831 (VEI 4?) And that Coseguina of Nicaragua in 1835 (VEI 5).

He painted spectacular sunsets caused by the sulfur aerosols, especially in his painting "Dido building Carthage" in 1815, now in the National Gallery in London.

William Turner - "Dido Building Carthage" - 1815 - National Gallery London.

William Turner - "Dido Building Carthage" - 1815 - National Gallery London.

The last peak pollution by sulfur dioxide were measured on September 10 at 2550 µg / m³ air, as illustrated in the graph of the Icelandic Environment Agency.

The cloud is moved towards the ENE and E, making the smell of sulfur perceptible to 1300 km on the west coast of Norway.
Above, the peak of sulfur dioxide emitted by the eruption fissure of the Holuhraun 10/09/2014 - doc.Environment Agency of Iceland. - One click to enlarge - - bottom dplacement gas cloud towards the coast Norwegian - Doc. IMO

Holuhraun on 11/09/2014 - photo Skapti Hallgrímsson / mbl.is

Holuhraun on 11/09/2014 - photo Skapti Hallgrímsson / mbl.is

Above, the peak of sulfur dioxide emitted by the eruption fissure of the Holuhraun 10/09/2014 - doc.Environment Agency of Iceland. - One click to enlarge - - bottom, displacement gas cloud towards the coast Norwegian - Doc. IMO
Above, the peak of sulfur dioxide emitted by the eruption fissure of the Holuhraun 10/09/2014 - doc.Environment Agency of Iceland. - One click to enlarge - - bottom, displacement gas cloud towards the coast Norwegian - Doc. IMO

Above, the peak of sulfur dioxide emitted by the eruption fissure of the Holuhraun 10/09/2014 - doc.Environment Agency of Iceland. - One click to enlarge - - bottom, displacement gas cloud towards the coast Norwegian - Doc. IMO

The sulfur fumes obscure the sun 08/09/2014 - photo Cambridge Univ. / Rebeccamorelle / BxAgxZPIQAA9fva

The sulfur fumes obscure the sun 08/09/2014 - photo Cambridge Univ. / Rebeccamorelle / BxAgxZPIQAA9fva

Sources :

- European Geosciences Union - Famous paintings help study the Earth’s past atmosphere - 25.03.2014 - link

- Further evidence of important environmental information content in red-to-green ratios as depicted in paintings by great masters - C. S. Zerefos & al. - link

- Zerefos, C. S., Gerogiannis, V. T., Balis, D., Zerefos, S. C., and Kazantzidis, A.: Atmospheric effects of volcanic eruptions as seen by famous artists and depicted in their paintings, Atmos. Chem. Phys., 7, 4027-4042, doi:10.5194/acp-7-4027-2007, 2007.

Lire la suite

Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques
The molecule coming from volcanoes that could replace antibiotics - photo Virginia Garin / RTL

The molecule coming from volcanoes that could replace antibiotics - photo Virginia Garin / RTL

An enzyme with amazing properties was found in the hot springs of Vesuvius, where the temperature is about 100 ° C.

In 2006, the General Direction of Army load researchers to study this enzyme with anti-neurotoxic properties, of interest in the fight against chemical attack. During their work, the researchers of URMITE / Research Unit on Infectious and Tropical Diseases of Medicine Timone Faculty in Marseille discovers her other qualities, which have just been published: the enzyme can destroy the molecules of communication between bacteria and prevent infection.


 

The habitat of Sulfolobus solfataricus - Photo Nature and Travel.

The habitat of Sulfolobus solfataricus - Photo Nature and Travel.

The enzyme, easy to produce, stable and durable, is particularly effective against gram-negative bacteria (including Pseudomonas) involved in 50% of nosocomial infections. According to Professor. Chabrière, "the enzyme restores the sensitivity to  antiobitiques. It is of great interest in the treatment of cystic fibrosis, whose deaths are mainly due to bacterial infection in the lung." Its scope can extend to chronic wounds affected by local treatment, such as in burns or "diabetic foot. "

Sulfolobus solfataricus contains thermostable enzymes contains and produce the proteine Pox Sso, which a variant is to the base of phosphotriesterase enzyme, allowing the degradation of toxic organophosphate and lactonases, inhibitors of bacterial virulence and limiter of  biofilm formation.

The protein T0420 Q97W15 SULSO Sulfolobus solfataricus - Doc. http://prodata.swmed.edu

The protein T0420 Q97W15 SULSO Sulfolobus solfataricus - Doc. http://prodata.swmed.edu

The in vitro efficacy was demonstrated and tested in vivo on rats inoculated with bacteria that cause pneumonia : a reduction in mortality by a factor of 4-8 was obtained.

A first application will be for the army with the development of antibacterial bandages for the wounded in operation, developed in partnership with Laboratoires Urgo ... an alternative to antibiotics to which bacteria are becoming increasingly resistant!

Other areas will be covered by a start-up "Gene & Greentech" : the remediation of farmland having absorbed too many pesticides, or the development of a coat for boats, to prevent algae growth on the hulls.

 

Sources :

- La Provence – Marseille : ils ont découvert comment dompter les bactéries / Des chercheurs marseillais ont élaboré une alternative aux antibiotiques. - link

- Gene & Greentech - link

-  PNAS - The complete genome of the crenarchaeon Sulfolobus solfataricus P2 - link

Lire la suite

Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques
El Calderon - red cinders on the edge of El Calderon - photo American southwest.

El Calderon - red cinders on the edge of El Calderon - photo American southwest.

Further north in El Malpais N.M., and more easily accessible than the other sites although a 4x4 vehicle is recommended, an area is home to two lava tubes, various other tunnels collapses, trench of lava and crater El Calderon from which most of the surrounding  lava flows emanate.
 

The crater of the cinder cone El Calderon - photo American southwest.

The crater of the cinder cone El Calderon - photo American southwest.

The crater of El Calderon cinder cone sees his center invaded by tall pines, of size larger than those of the same species growing on the banks, because of the wind protection and improved water availability.

The trees have their tops curiously at the same level, whether on the floor, along the slopes or on the edges.

Lava Trench - Trench V-shaped radiating from El Calderon - photo American southwest.

Lava Trench - Trench V-shaped radiating from El Calderon - photo American southwest.

Lava Trench - details of the walls - photo American southwest.

Lava Trench - details of the walls - photo American southwest.

Lava Trench is a V-shaped trench, filled with large blocks formed by the rapid movement of the lava. The walls are made ​​of thin layers from different lava flows from the crater El Calderon.

One of the Double Sinks - photo American southwest.

One of the Double Sinks - photo American southwest.

Bat Cave is a small lava tube that houses at least four species of bat. So entry is prohibited throughout the year, for obvious reasons of protection.

Double Sinks, two sinkholes formed by the collapse of a lava tube, with near-vertical walls that prevent a possible descent.

Junction Cave form a lava tube of 400 meters long, with a branch; the floor is made of broken rocks, giving way to
a muddy ground near the end where the ceiling falls.
 

Access map to El Calderon area - American southwest

Access map to El Calderon area - American southwest

Sources :

- American Southwest - El Calderon, El Malpais National Monument

- Global Volvanism Program - Malpais.

Lire la suite

Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques
View over the lava field of El Malpais, seen from Sandstone Bluffs - photo Undangaray

View over the lava field of El Malpais, seen from Sandstone Bluffs - photo Undangaray

El Malpais National Monument form a high valley in central New Mexico, USA. The area is covered with black lava flows covering 344 square kilometers.

In Spanish meaning "bad lands", this volcanic field, located between 1950 and 2560 meters above sea level, has cinder cones, spatter cones, a network of long lava tunnels, some ice caves and one of the largest natural arches of the state, known as "La Ventana".

The area is a traditional point of contact between cultures Mogollon, Anasazi, Sinagua and Patayan.



Left, Location of El Malpais compared to the volcanism of the Colorado Plateau - right, left access simplified map.

 Landscape of El Malpais, the Zuni-Acoma trail - photo NPS

Landscape of El Malpais, the Zuni-Acoma trail - photo NPS

Left, Location of El Malpais compared to the volcanism of the Colorado Plateau - right, left access simplified map. Left, Location of El Malpais compared to the volcanism of the Colorado Plateau - right, left access simplified map.

Left, Location of El Malpais compared to the volcanism of the Colorado Plateau - right, left access simplified map.

The Zuni-Bandera volcanic field:

The El Malpais structures are part of the Zuni-Bandera volcanic field, the second largest volcanic field in the Basin and Range Province.

The Zuni-Bandera field covers an area of ​​2,460 square kilometers in the southeastern boundary of the Colorado Plateau, at the intersection of the basin of the Rio Grande and the Jemez alignment. Its activity s' ranges from 3.8 to 3.7 Ma and 1.7 Ma.

At the edge of El Malpais, La Ventana arch is a natural sandstone arch.

Close to Sandstone Bluffs, a viewpoint offers spectacular views of the lava ... both are close to the 117 highway.


 

La Ventana arch - photo stephen-weaver.com - Southwest desert lovers

La Ventana arch - photo stephen-weaver.com - Southwest desert lovers

El Malpais lava flows:

They are of different ages and backgrounds. The most recent is the McCarty lava flow, on the west side, dated about 3,000 years. The oldest rocks are difficult to detect because of the landfill and cover.

The cinder cones of the "Chain of Craters" approximately 600 or 700,000 years.

Mount Taylor, northeast, old is 1.5 to 3.3 Ma.

Map of lava flows and their point of origin / age - doc.El Malpais - Caving / National Park Service

Map of lava flows and their point of origin / age - doc.El Malpais - Caving / National Park Service

El Malpais - pahoehoe flows - photo Markus Manske

El Malpais - pahoehoe flows - photo Markus Manske

The structures present in Western National Monument, located in a mountainous and forested landscape, are less accessible but more spectacular than the rest of the park. Twenty-five cinder cones and the remains of a lava tube system from the Bandera crater, dating from 10,500 to 9,500 years.

"Big Tubes" are accessible by unpaved forest road that leads to the Big Four Skylight and to the Four Windows, lava tubes containing permanent ice, and a series of bridges of lava remains of a collapsed lava tube.

Adequate equipment is recommended: helmet, gloves and knee pads, fleece, waterproof and good sources of light.

El Malpais - one of the Seven Bridges, lots of snow nestled in its shadow - photo American Southwest

El Malpais - one of the Seven Bridges, lots of snow nestled in its shadow - photo American Southwest

Seven bridges:

Only short sections of the roof of lava tunnel, collapsed largely, shaped bridges amounting to fifteen feet above the floor, covered with blocks and bordered by steep walls. Some lava bridges withstand much heavy pines.

Four Windows cave - photo American southwest

Four Windows cave - photo American southwest

Four Windows cave - at the entrance of the lava tube, you can see the floor in pahoehoe lava - photo naxja.org

Four Windows cave - at the entrance of the lava tube, you can see the floor in pahoehoe lava - photo naxja.org

Four Windows cave :

So named because of the small openings in the roof near the main entrance, the Windows Four lava tube present there a small moss garden, in the area where a little light penetrates, and populated by various invertebrates.

Photo at:
http://brianleddyphoto.photoshelter.com/image/I0000BeUhYhn..eY

Ice stalagmites are formed there in the winter and can be keep, the temperature between -2 and +2 ° C.

Extensive bacterial coat, whitish to golden hues, lines the walls of the tunnel adjacent to the algal mats in the twilight zone, and cover up to 25-75% of the walls in dark area. It consists essentially of actinomycetes and is devoid of any invertebrate, due to secretion of repellents antibiotics.

Tomorrow, the Big Skylight cave.

 

Sources :

- National Park Service - El Malpais National Monument - link

- El Malpais: In the Land of Frozen Fires - A History of Occupation in El Malpais Country - by Neil C. Mangum 1990 - link

- Nature of Bacterial Communities in Four Windows Cave, El Malpais National Monument, New Mexico, USA - by Diana E. Northup & al - link 

- Science in action – Caves lime - link 

Lire la suite

Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques
Eruptive fissures in Holuhraun - 2014.09.06 - Norðurflug

Eruptive fissures in Holuhraun - 2014.09.06 - Norðurflug

The in-flight monitoring of the September 6 relates Bárðarbunga, Dyngjiujökull,in addition of the eruption area in Holuhraun.

Radar measurements show significant changes in glacier area: subsidence of more than 15 meters in the center of the Bárðarbunga caldera ... this volume is 0.25 cubic kilometers, or 250 million m³, volume ever yet observed in Iceland since the early observations, except those related to the formation of the caldera Öskjuvatn of Askja in 1875.

No sign of eruption or increased geothermal activity was observed in the caldera, which limits the causes of earthquakes to subsidence and movement of magma in the subsurface to the northeast.

Bárðarbunga. Subsidence of the glacier surface (m). A comparison of the measurement of TF-FMS yesterday and a Lidar map from 2011 as well as surface measurements from June this year. Institute of the Earth Sciences, University of Iceland.

Bárðarbunga. Subsidence of the glacier surface (m). A comparison of the measurement of TF-FMS yesterday and a Lidar map from 2011 as well as surface measurements from June this year. Institute of the Earth Sciences, University of Iceland.

For Dynjujökull, a wide shallow depression was observed at 10 km from the edge of the glacier.
Another depression, located 6 km from the edge of the glacier, has deepened: today it is 35 meters deep.

These depressions are likely signs of small and short subglacial eruptions.


 

2014.09.06 - Subsidence observed in Bárðarbunga

2014.09.06 - Subsidence observed in Bárðarbunga

In Holuhraun, two cracks remain active on all three, with greater intensity on the first. The lava extends ENE and should reach the main branch of the river Jökulsá á Fjöllum within 24 hours, if the feed ratio (40 meters / hour) remains the same, according to volcanologist Thorvaldur Thordarson.

The area covered by lava than 14 square kilometers.

Mýflug Air flight above the eruptive site 05/09/2014 - aircraft for scale - photo Mýflug Air / Axel Sigurðarson

Mýflug Air flight above the eruptive site 05/09/2014 - aircraft for scale - photo Mýflug Air / Axel Sigurðarson

 "Warm front" - the lava flow on 09.05.2014 - photo Artic pictures

"Warm front" - the lava flow on 09.05.2014 - photo Artic pictures

 Extension of the lava field on 09/06/2014 - Doc. IES

Extension of the lava field on 09/06/2014 - Doc. IES

Volcanic activity remains stable, but the seismic activity has decreased in number of events.

An earthquake of M5 is scored in the caldera Bárðarbunga the 06.09 at 5:40 UTC.

Location and magnitude of earthquakes on the northern Vatnajökull / Dyngjujökull - Doc. IMO
Location and magnitude of earthquakes on the northern Vatnajökull / Dyngjujökull - Doc. IMO

Location and magnitude of earthquakes on the northern Vatnajökull / Dyngjujökull - Doc. IMO

Sources :

IMO - University of Iceland - Iceland Review - RUV

Lire la suite

Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques
The two new cracks in Holuhraun - photo laraomars / RUV

The two new cracks in Holuhraun - photo laraomars / RUV

According to the Civil Protection and the University of Iceland , new eruptive fissures have opened between the first crack and Dyngjujökull glacier, around 7am UTC. on September 5.

An overview
by scientists has found that two cracks are developed in the graben overlying the intrusion. The lava fountains are substantially smaller than those characterizing the former fisssure, also still active. Steam and large quantities of SO2 are released into the atmosphere. The cauldron in the Dyngjujökull seems to have deepened since the last observation.

Holuhraun - 09/05/2014 - new cracks on the right, the former on the left degassing more strongly - photo Snorri B. Jónsson. RUV

Holuhraun - 09/05/2014 - new cracks on the right, the former on the left degassing more strongly - photo Snorri B. Jónsson. RUV

Dyngjujökull - Cauldron dug into the glacier - photo almannavarnir during a 09/05/2014 flight.

Dyngjujökull - Cauldron dug into the glacier - photo almannavarnir during a 09/05/2014 flight.

 Radar Image of the cauldron - doc.via RUV 09/05/2014

Radar Image of the cauldron - doc.via RUV 09/05/2014

The measurements show a slight increase in conductivity in Jökulsá á Fjöllum, the main drainage of the glacier, possibly related to rainwater drains into the river through the recent lava (J.A. Stevenson).

On seismicity, two earthquakes of 5.3 and M4,4 were detected around midnight, September 5, in the caldera of Bárðarbunga.

Extension of the lava field with dates - Doc. University of Iceland

Extension of the lava field with dates - Doc. University of Iceland

Holuhraun - the original crack is more active than the two new - photo mbl.is / FOR rni Sæberg

Holuhraun - the original crack is more active than the two new - photo mbl.is / FOR rni Sæberg

Displacements of the GPS stations 09.05.2014 - The opening of a rift is confirmed by movements in the opposite sense at the contact Holuhraun / Dyngjujökull. - doc.IMO

Displacements of the GPS stations 09.05.2014 - The opening of a rift is confirmed by movements in the opposite sense at the contact Holuhraun / Dyngjujökull. - doc.IMO

Sources :

IMO - University of Iceland - RUV - mbl.is - Iceland Review

Lire la suite

Publié le par Bernard Duyck
Publié dans : #Actualités volcaniques
 Holuhraun - lava fountains from Reykjavik Helicopters

Holuhraun - lava fountains from Reykjavik Helicopters

 The plume and ashes of the eruption Holuhraun - photo Geir Ólafsson / Iceland Review

The plume and ashes of the eruption Holuhraun - photo Geir Ólafsson / Iceland Review

The intensity of the ongoing eruption continues unabated ... the lava flow towards the ENE grew substantially and the covered area is approximately 10.8 square kilometers. No evidence of subglacial eruption, or changing in discharge and conductivity in the Jökulsá River.

The low-frequency tremor, measured yesterday stopped around 21:30 to resumeon 04.09  morning in a minor key. The source of the tremor was not identified with certainty; one possible explanation is according to scientists, an interaction between magma and water.

Extension of the lava field in Holuhraun with dates - map IMO

Extension of the lava field in Holuhraun with dates - map IMO

The fissure in Holuhraun - a plane in down center for scale - photo Ragnar Sigurdsson / Arctic Images

The fissure in Holuhraun - a plane in down center for scale - photo Ragnar Sigurdsson / Arctic Images

Cracks in Holuhraun - photo RUV - pic.twitter.com/y0qsI5hjSn 02.09.2014

Cracks in Holuhraun - photo RUV - pic.twitter.com/y0qsI5hjSn 02.09.2014

  2014.09.03 - Crevasse near the site of eruption - photo Lara Omarsdottir / via Twitter

2014.09.03 - Crevasse near the site of eruption - photo Lara Omarsdottir / via Twitter

Earthquakes are still detected in the northern part of the dyke, in the eruption site, and under the Dyngjujökull. Four tremors above magnitude 4 were detected in the caldera of Bárðarbunga, the largest M4,8 at 3:09 tonight.
 

Location and magnitude of earthquakes in northern Vatrnajökull the 04.09.2014 / 15:05 - Doc. IMO
Location and magnitude of earthquakes in northern Vatrnajökull the 04.09.2014 / 15:05 - Doc. IMO

Location and magnitude of earthquakes in northern Vatrnajökull the 04.09.2014 / 15:05 - Doc. IMO

Emissions of sulfur dioxide continue and, due to low wind conditions, are concentrated near the site of eruption, reaching dangerous levels for health

Regarding the graben that forms south of the eruption, cracks identified by the radar, and some well visible by aerial observation, show horizontal and vertical above the dyke travel.

 

Radar images of the graben (rift) - one click to enlarge - doc. University of IcelandRadar images of the graben (rift) - one click to enlarge - doc. University of Iceland

Radar images of the graben (rift) - one click to enlarge - doc. University of Iceland

Position and movement of GPS stations - the distance in the opposite direction on each  side of the dyke, shows the opening of the rift in the ice Dyngjujölull - doc IES

Position and movement of GPS stations - the distance in the opposite direction on each side of the dyke, shows the opening of the rift in the ice Dyngjujölull - doc IES

A picture taken at night in infrared details the front washing and crack, warmer zones
 

Top, high-resolution infrared Holuhraun composite - bottom Holuhraun in infrared at night - Doc. NASA MODIS Aqua
Top, high-resolution infrared Holuhraun composite - bottom Holuhraun in infrared at night - Doc. NASA MODIS Aqua

Top, high-resolution infrared Holuhraun composite - bottom Holuhraun in infrared at night - Doc. NASA MODIS Aqua

As a bonus, because we will never do the same ... "JUMP INTO HELL" - a photo of Iurie Belegurschi Photography

As a bonus, because we will never do the same ... "JUMP INTO HELL" - a photo of Iurie Belegurschi Photography

Sources :

- IMO

- Institute of Earth Siences / University of Iceland

- Iceland review - link

- Nasa visible Earth - infrared views of Bardarbunga - link

Lire la suite

<< < 10 11 12 13 14 15 16 17 18 19 20 > >>

Articles récents

Hébergé par Overblog