Archive | Lava Dome RSS for this section

New flank eruption reported at Erta Ale volcano in Ethiopia

Hot spots on Erta Ale – the reported flank eruption is not (yet) visible (MODIS data, Univ. Hawai’i)
 
News have come in about a fissure eruption at the SE flank of the volcano, approx. 7 km distance from the summit caldera and its lava lake (which partially collapsed on and after 20 Jan). 
 
According to our local correspondents, the activity at the summit has decreased a lot, which would be in accordance with the scenario of lava now being drained through lower fissures on the flanks. Apparently, the fissures opened on or shortly after 21 Jan and produce large amounts of lava now flowing into the direction of Afdera.
Courtesy of volcanodiscovery.com

Relatively intense activity at Stromboli volcano Eolian Islands in Italy

Stromboli’s crater terrace this morning with glow from the central vent (image: INGV Catania Pizzo webcam)
 
The activity at the “Lighthouse of the Mediterranean” has been much more intense recently than during most of the year. 
 
Explosions mainly from the eastern vent (towards Stromboli village) have been observed at intervals of approx. 10 minutes, ejecting dense jets of incandescent lava to up to estimated 150 m height. 
 
Continuous glow can be seen from adjacent vents in the central crater area as well, suggesting a relatively high lava column inside the conduit.
Courtesy of volcanodiscovery.com

Intense activity continues, possible lava flows outside the caldera at Erta Ale volcano in Ethiopia

Hot spots on Erta Ale (MODIS data, Univ. Hawai’i)
Activity remains elevated at the volcano in the Danakil. The latest available information show simultaneous effusive activity from both the north and the south crater – the latter, which contained the famous lava lake has been overflowing and building a new lava shield that started to partially fill the summit caldera. 
 
It seems that lava flows have started to overflow even outside the caldera through the low part of the rim on the NE side (judging from satellite data).
Courtesy of volcanodiscovery.com

Europe’s Most Dangerous Supervolcano “Campi Flegrei” is Reawakening

Just below millions of people there is a supervolcano that has begun to show signs of reawakening. The supervolcano, Campi Flegrei, is 8 miles wide and sits beneath the Bay of Naples offshore Italy. Recent monitoring of the volcano points to a reawakening of one of the largest volcanoes in Europe.
 
An international team of geoscientists have monitored the volcano’s caldera for signs of activity and recently published results in the journal Nature Communications on the increased danger of an eruption.
 
Campi Flegrei, which means “burning fields” in Italian, is believed to have formed hundreds of thousands of years ago and has erupted on several occasions in recent geologic time. The initial eruption, which occurred 200,000 years ago triggered a “volcanic winter” from the massive amount of ash ejected into the atmosphere. The volcano then erupted again 40,000 and 12,000 years ago.
 
The eruption 40,000 years ago is thought to have wiped out most of the European Neanderthals and was one of the largest volcanic eruptions of all time. In recent memory, Campi Flegrei erupted in 1538 for 8 days straight, sending ash across Europe and forming the new mountain Monte Nuovo.
 
Recent measurements from the Campi Flegrei volcano indicate it is approaching what is called the critical degassing pressure (CDP), a pressure at which the volcano can begin a phase of volatility and volcanic unrest. The CDP is generally speaking a pressure where volcanic gas can release from the underlying magma, heat localized hydrothermal vents, fluids, and rocks. This increased pressure and heat can trigger deformation of the overburden rock and ultimately rock failure, i.e. a volcanic eruption.
 
Scientists have measured accelerated deformation of the volcano, which has literally risen recently due to increased gaseous pressures. Scientists have measured a 1.25 feet rise of the volcano’s ground since 2005. Gas at high pressures in the subsurface is exceptionally dangerous as it can easily and quickly lead to an unconstrained positive feedback loop. Imagine gas in solution in magma, which is relatively stable.
 
If that gas begins to escape and rise in the Earth’s subsurface through magma, the gas will subsequently reduce the overlying pressure of the magma below it. That in turn allows for more gas to come out of solution and rise in the magma column. In an instant, you can have a runaway situation whereby decompressed gas allows for more decompression and an eventual blowout. This is not dissimilar to some situations seen during oil and gas well blowouts.
 
The location of Campi Flegrei is especially alarming, located immediately near the metropolitan area of Naples, a very densely populated metropolitan area. The volcano is therefore actively monitored by the Italian National Institute of Geophysics located in Rome, where real time measurements are analyzed for increasing threat.
 
Despite the increasing signs of activity, it’s very hard to determine the “tipping point” at which the volcano begins erupting. However, the Italian government recently raised the volcano’s threat level from green to yellow, which requires constant scientific monitoring for changes in volcanic behavior. The most common signs of increased likelihood of an eruption are increased gas output (decreased gas pressure), elevation rise on the volcano’s surface, and increased seismicity within the volcano.
 
Unfortunately, the best thing we can currently do is actively monitor the volcano for signs of further increasing activity. However, an eruption could not happen for the next century, it’s impossible to accurately model when these events will occur. Similar to many geologic processes on Earth (earthquakes, volcanic eruptions, sinkholes, etc.) the signs of decreasing stability are easy to detect but the tipping point at which the event occurs is very hard to predict.
Courtesy of chiangraitimes.com

***ALERT LEVEL RAISED TO RED*** Bogoslof Volcano, Alaska

Bogoslof Volcano, Alaska Alert Level Raised To RED

Volcano Alert

Another explosive eruption occurred at the volcano a few hours ago (at around 09:30 AKST local time), the Alaska Volcano Observatory reported. The alert level of Bogoslof was raised back to red. 
 
“A Coast Guard ship in the vicinity reported ash emission as well as ejection of lava and fragmental material. The eruption cloud did not penetrate the regional cloud tops at 30,000 ft and winds are to the north-northeast. According to the Coast Guard, ash emission subsided at about 10:37 AKST (19:37 UTC). On the basis of this information, the Aviation Color Code is raised to RED and the Alert Level to WARNING.” 
 
Courtesy of volcanodiscovery.com

Moderate Explosion And Small Pyroclastic Flow At Sinabung Volcano In Sumatra, Indonesia

Eruption of Sinabung this morning at 07:46 local time (image: PVMBG)
An explosion this morning produced an ash plume that rose 1500 m and a small pyroclastic flow of 700 m length. This shows that the supply of magma continues even though most of the recently emplaced dome has disappeared during past week’s collapse events.
Courtesy of volcanodiscovery.com

Volcano on Rome’s doorstep is slowly reawakening

mount-vesuvius-0.jpg
The new findings raise fears that parts of Rome could suffer a similar fate to that of Pompeii after the eruption of Mount Vesuvius Rex
Increased activity below the earth’s surface suggests volcano just 10km from the Italian capital is getting close to another eruption
A dormant volcano just outside Rome could be slowly reawakening, scientists have said, raising fears of a Pompeii-style ash-and-rock cloud sweeping across the Italian capital.
 
An eruption in the Colli Albani Volcanic District (CAVD), which is around 10km from Rome, would have a devastating impact on much of the city. 
 
In a study published in the journal Geophysical Research Letters, an international team of researchers reported that the ground in the region is rising by 2-3mm per year and underground chambers located several kilometres below the towns of Ariccia, Castel Gandolfo and Albano are filling up with magma – signs that the previously dormant volcano is rumbling back to life.
 
Satellite imagery and seismographic charts also record the volcano’s slow awakening.    
 
However, while the volcano’s increased activity is a cause for concern, experts believe a possible eruption could still be 1,000 years away.
 
Previous studies have suggested the volcano tends to erupt around every 40,000 years.
 
But now scientists believe that could be narrowed to 30,000 years – bringing the prospect of an eruption much closer.
 
If the volcano did erupt, it would produce a huge cloud raining down ash and lava on parts of Rome. The cloud would obscure the sun in countries as far away as Latin America, scientists believe.
 
Experts say the long gaps between eruptions are a cause for concern because they allow time for large quantities of magma to build up and pressure to mount below the earth’s surface. This means the eventual eruption is likely to be bigger and more powerful. 
 
“When the eruption happens, it has an explosive effect, like opening a champagne bottle after shaking it,” Fabrizio Marra, who led the study, told La Repubblica.
 
“This sort of process has, for example, caused the string of earthquakes that hit this area at the beginning of the 1990s, with minor quakes and a few cases of magnitude four quakes.”
 
Mr Marra said people living near the volcano should not fear an eruption – at least not yet.
 
The more imminent threat is from earthquakes triggered by the increased activity under the earth’s crust.
 
Earthquakes can, in certain circumstances, trigger volcanic eruptions but this is not currently a risk in Rome because the volcano is still too far away from its next eruption. 
 
Mr Marra said: “It has been ascertained that a seismic event could trigger a volcanic eruption, as happened in the US with Mount St Helens. But it can only happen with a volcano on the verge of erupting, at these levels there is no possible disturbance that could reach the magma chambers.”
 
The team, from the National Institute of Geophysics and Volcanology in Rome, mapped 600,000 years of the region’s history and assessed the habits of the volcano. 
 
They concluded that the cycle of past eruptions suggest another is due within the next 1,000 years – a finding in line with the increased volcanic activity in the region. 
 
The warning comes as Italy’s biggest earthquake in 36 years left more than 15,000 people homeless in and around the town of Norcia in central Italy.
 
A number of historic buildings were damaged or destroyed by the 6.6 magnitude quake. In August, 200 people were killed by a slightly smaller earthquake that hit the nearby village of Accumoli.
Courtesy of independent.co.uk

32 Volcanoes Are Currently Erupting Worldwide

Daily active volcano map

Courtesy of volcanodiscovery.com