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Volcanos / Volcanoes

It's very abrasive, so you wouldn't want to sail through it.
I guess it will all end up on a beach somewhere.
 
Normally, lava extruded underwater forms pillow lavas:
http://en.wikipedia.org/wiki/Pillow_lava

This is why I was surprised that this NZ example comes from an underwater volcano. As Wiki says,
"Pumice is typically created when super-heated, highly pressurized rock is violently ejected from a volcano.
...
Pumice is a common product of explosive eruptions "

http://en.wikipedia.org/wiki/Pumice

But the same article also says:
"In 1979, 1984 and 2006, underwater volcanic eruptions near Tonga created large pumice rafts, some as large as 30 km that floated hundreds of kilometres to Fiji."
 
Mount Sakurajima exploded a couple of hours ago

Saw it live on webcam http://122.20.254.201:443/Camera10.

Upper part of the mountain was covered in magma and glowing rocks from the explosion. The explosion was over in three minutes. It's just a matter of clicking on the correct tab in the browser at the exact correct moment.

Hopefully someone has recorded the webcam today. I will come back with a link to the video if it is published.
 
Argentina and Chile order evacuation of Copahue volcano

Chile and Argentina have ordered the evacuation of some 3,000 people living near the Copahue volcano in the south of their shared border.
The authorities in both countries issued a red alert - the highest possible - saying the Chilean volcano could erupt imminently.

The 2,965m (nearly 10,000ft) volcano - which sits in the Andes cordillera - has so far only spewed gas.
Thousands of minor earth tremors have been registered in the area.
"This red alert has been issued after monitoring the activity of the volcano and seeing that it has increased seismic activity," Chilean Interior Minister Andres Chadwick said in a news conference.
"There is a risk that it can start erupting."

According to Chile's Emergency Office, the evacuation will affect some 460 families living within a 25km (15 miles) radius of Copahue.
It said it could last about 48 hours, but could be delayed because of heavy rains in the region.

In Argentina, the authorities had first declared a "yellow alert," but later revised it to the highest level.
They have now ordered the evacuation of about 600 people from the town of Caviahue to the neighbouring city of Loncopue.

Last December, Chile also issued a red alert after Copahue - one of the most active volcanoes in the region - began spewing ash and gas, with smoke raising nearly 1.5km in the sky.
Nearby residents were temporarily evacuated, and planes flying over the southern Andes warned to avoid the area.

Hundreds of flights were cancelled last year due to the eruption of another volcano in southern Chile.

The Puyehue eruption caused huge economic damage not only to property in the area but also to tourism in Bariloche and other resorts.

http://www.bbc.co.uk/news/world-latin-america-22684322
 
Ancient Irish texts show volcanic link to cold weather
By Matt McGrath, Environment correspondent, BBC News

Researchers have been able to trace the impact of volcanic eruptions on the climate over a 1200 year period by assessing ancient Irish texts.
The international team compared entries in these medieval annals with ice core data indicating volcanic eruptions.
Of 38 volcanic events, 37 were associated with directly observed cold weather extremes recorded in the chronicles.
The report is published in the Journal, Environmental Research Letters.

In the dim light of the dark ages, the Irish literary tradition stands out like a beacon.
At monastic centres across the island, scribes recorded significant events such as feast days, obituaries and descriptions of extreme cold and heat.
These chronicles are generally known as the Irish Annals and in this report, scientists and historians have looked at 40,000 entries in the texts dating from 431 to 1649.

The researchers also looked at the Greenland Ice Sheet Project (GISP2) ice core data.
When volcanoes erupt, they produce sulphate aerosol particles which down the centuries have been deposited on and frozen in ice sheets, leaving an extremely accurate temporal record of the event.

Scientists say these particles reflect incoming sunlight and can cause a temporary cooling of the earth's surface. In a country with a mild maritime climate like Ireland, these colder events would have a significant impact.
"When the weather that is cold enough to allow you to walk over a lake in Ireland, it is pretty unusual," lead author Dr Francis Ludlow, from Harvard University told BBC News.
"When it happened it was remarkable enough to be recorded pretty consistently."

The scientists in the team identified 48 volcanic eruptions in the time period spanning 1219 years. Of these, 38 were associated closely in time with extreme weather events identified in the Irish texts.
"These eruptions occur and they override existing climate patterns for a period of two or three years," said Dr Ludlow.

"And it is clear from the sources that they cause a lot of devastation among societies at the time whether it was the mass mortality of domestic animals or humans or indirectly by causing harvest failure."
The research team believe the texts are accurate as the annals also record solar and lunar eclipses which can be compared with other contemporary sources.

The keen recording of weather though had another motivation.
"A lot of these scribes are working in monasteries, in some time periods they are interpreting these weather events as divine omens or portents as signals of the coming of the last days," said Dr Ludlow.
"That was one of their motivations so we are able to use the records that were created for a completely different purpose that the scribes would never have conceived."

The researchers say that one expected effect of volcanic eruptions that occur in tropical regions is to make for milder winters in northern latitudes.
But in this study they found several instances of these type of eruptions causing extremely cold winters in Ireland. The team believe their work shows the complex nature of volcanic impacts on climate, and they say there are lessons for the future in the ancient texts.

"That tells us a lot about what sort of weather we might expect in the British isles when the next big eruption goes off," said Dr Ludlow.
"We might want to buy a bit more salt for the roads."

http://www.bbc.co.uk/news/science-environment-22786179
 
Popocatepetl volcano causes more Mexico flight chaos

US airlines have cancelled flights into and out of Mexico City for a second day over fears that ash from a rumbling volcano could affect their planes.
Delta and United Airlines were among the companies that stopped at least a dozen flights on Friday.
On Thursday, more than 40 flights were cancelled, leaving hundreds of passengers stranded.

Popocatepetl volcano has been rumbling all year, and began spewing ash and steam earlier in the week.
Airport authorities insisted there was no danger.
An unnamed airport official told the AFP news agency: "There is a very thin presence of ash, which does not harm operations or affect equipment."

But Jorge Andres Gomez, a spokesman for the airport, said any change in the wind or intensity of the volcano would complicate the situation.

US Airways, Delta, United, American and Alaska Airlines all cancelled flights on Thursday.
The routes affected by the cancellations were flights to Houston, Dallas, Denver, Phoenix, Chicago and Los Angeles.

American said in a statement that it had taken the action as a precaution.
"We are closely monitoring the situation in Mexico City as volcanic ash continues to be emitted from Popocatepetl," said American Airlines spokesman Matt Miller.

Mexican airlines continued to fly into the airport as scheduled.
Most operations were getting back to normal later on Friday, officials said.
The authorities established an 11-km (seven-mile) no-go zone around the volcano, which lies 70km (40 miles) south-east of the airport.

Popocatepetl, which is 5,452m (17,900ft) high, has intensified in activity since May, and the alert level is currently set one notch below evacuation level.
Mexico's National Disaster Prevention Centre reported tremors and columns of ash and vapour at Popocatepetl on Friday.
It advised people living around the volcano to take precautions such as using masks, covering water supplies and staying indoors.

http://www.bbc.co.uk/news/world-latin-america-23193828
 
This one won't be delaying any aircraft though:

'World's largest volcano discovered beneath Pacific

Scientists say that they have discovered the single largest volcano in the world, a dead colossus deep beneath the Pacific waves.
A team writing in the journal Nature Geoscience says the 310,000 sq km (119,000 sq mi) Tamu Massif is comparable in size to Mars' vast Olympus Mons volcano - the largest in the Solar System.

The structure topples the previous largest on Earth, Mauna Loa in Hawaii.
The massif lies some 2km below the sea.
It is located on an underwater plateau known as the Shatsky Rise, about 1,600km east of Japan.
It was formed about 145 million years ago when massive lava flows erupted from the centre of the volcano to form a broad, shield-like feature.

The researchers doubted the submerged volcano's peak ever rose above sea level during its lifetime and say it is unlikely to erupt again.
"The bottom line is that we think that Tamu Massif was built in a short (geologically speaking) time of one to several million years and it has been extinct since," co-author William Sager, from the University of Houston, US, told the AFP news agency.

"One interesting angle is that there were lots of oceanic plateaus (that) erupted during the Cretaceous Period (145-65 million years ago) but we don't see them since. Scientists would like to know why."

Prof Sager began studying the structure two decades ago, but it had been unclear whether the massif was one single volcano or many - a kind that exists in dozens of locations around the planet.

While Olympus Mons on Mars has relatively shallow roots, the Tamu Massif extends some 30 km (18 miles) into the Earth's crust.

And other volcanic behemoths could be lurking among the dozen or so large oceanic plateaux around the world, he thought.
"We don't have the data to see inside them and know their structure, but it would not surprise me to find out that there are more like Tamu out there," said Dr Sager.

"Indeed, the biggest oceanic plateau is Ontong Java plateau, near the equator in the Pacific, east of the Solomons Islands. It is much bigger than Tamu -- it's the size of France."

The name Tamu comes from Texas A&M University, where Prof Sager previously taught before moving to the University of Houston.

http://www.bbc.co.uk/news/science-environment-24007339
 
Mystery 13th Century eruption traced to Lombok, Indonesia
By Jonathan Amos, Science correspondent, BBC News

Scientists think they have found the volcano responsible for a huge eruption that occurred in the 13th Century.
The mystery event in 1257 was so large its chemical signature is recorded in the ice of both the Arctic and the Antarctic.
European medieval texts talk of a sudden cooling of the climate, and of failed harvests.

In the PNAS journal, an international team points the finger at the Samalas Volcano on Lombok Island, Indonesia.
Little remains of the original mountain structure - just a huge crater lake.
The team has tied sulphur and dust traces in the polar ice to a swathe of data gathered in the Lombok region itself, including radiocarbon dates, the type and spread of ejected rock and ash, tree-rings, and even local chronicles that recall the fall of the Lombok Kingdom sometime in the 13th Century.

"The evidence is very strong and compelling," Prof Clive Oppenheimer, from Cambridge University, UK, told the BBC.

Co-worker Prof Franck Lavigne, from the Pantheon-Sorbonne University, France, added: "We conducted something similar to a criminal investigation.
"We didn't know the culprit at first, but we had the time of the murder and the fingerprints in the form of the geochemistry in the ice cores, and that allowed us to track down the volcano responsible."

The 1257 eruption has been variously linked with volcanoes in Mexico, Ecuador and New Zealand.
But these candidates fail on their dating or geochemistry, the researchers say. Only Samalas can "tick all the boxes".

The team's studies on Lombok indicate that as much 40 cubic kilometres (10 cubic miles) of rock and ash could have been hurled from the volcano, and that the finest material in the eruption plume would likely have climbed 40km (25 miles) or more into the sky.
It would have had to be this big in order for material to be carried across the entire globe in the quantities seen in the Greenland and Antarctic ice layers.

The impact on the climate would have been significant.
Medieval texts describe atrocious weather the following summer in 1258. It was cold, and the rain was unrelenting, leading to flooding.

Archaeologists recently put a date of 1258 on the skeletons of thousands of people who were buried in mass graves in London.
"We cannot say for sure these two events are linked but the populations would definitely have been stressed," Prof Lavigne told BBC News.

In comparison with recent catastrophic blasts, Samalas was at least as big as Krakatoa (1883) and Tambora (1815), the researchers believe.
The ice cores do hold clues to yet another colossal event in about 1809, but, like Samalas before it, finding the source volcano has been difficult.
Prof Oppenheimer said: "It's outstanding that we haven't come across evidence for it. Where in the world could you bury such bad news?"

http://www.bbc.co.uk/news/science-environment-24332239
 
Like the dark ages wasn't dark enough, then this came?
 
8 April 2014 Last updated at 13:59
Volcanic islands merge in Pacific Ocean

A volcanic island in the Pacific Ocean has merged with its neighbour to form one landmass, the US space agency says.
The merged island lies some 1,000km (621mi) south of Tokyo, the result of eruptions on the seafloor that have spewed enough material to rise above the water line.

In November 2013, a new island sprouted near to Nishino-shima, another volcanic landmass that last expanded in the 70s.
Four months later, the new and old islands are one island.
The newer portion of the island - which was referred to as Niijima - is now larger than the original Nishino-shima landmass.
The merged island is slightly more than 1km (3,280ft) across.

According to Nasa, two cones have formed around the main volcanic vents and stand more than 60m above sea level.
Volcanic lava flows are reported to be most active now on the south end of the island.

The new landmass lies in the Ogasawara (Bonin) Island chain.

http://www.bbc.co.uk/news/science-environment-26941017
 
Lab volcano gives lightning clues
By Jonathan Amos, Science correspondent, BBC News, Vienna

Don't do this at home. Corrado Cimarelli makes his own volcanoes that spout ash vertically at hundreds of metres a second.
The Italian is studying the awesome sight of lightning that is often observed in eruption plumes.
His "lab volcano" allows him to recreate and study the processes that give rise to the necessary electrical conditions.

The hope eventually is to learn something about the nature of volcanoes purely from their lightning behaviour.
“The lightning can tell us a lot about the structure of the eruption plume and the ash particle sizes within it,” Dr Cimarelli told BBC News.
Such information could give an indication of whether a particular eruption was likely to pose a risk to aviation, he added.

The Ludwig Maximilian University of Munich researcher was speaking here in Vienna at the European Geosciences Union General Assembly.
His lab volcano is no mountain; the vent is only about 3cm wide. But it is able to reproduce the conditions that trigger volcano lightning very successfully.

The set-up is essentially a hot, pressurised metal tube from which real volcano ash particles (from Popocatepetl in Mexico) are accelerated at high speed.
Slow-motion video captures mini-lighting strikes dancing around the exhaust jet.

To get discharges in a real volcano, there needs to be a large electrical potential between different regions of the eruption cloud.
Ash particles can be charged by fracturing them and by rubbing them together.
If the charges are big enough and are located in the right places in the plume, a bolt can jump from one location to another.

It is clear from the experiments that particle size is a critical factor. The smaller the particles, the higher the number of bolts.
“That’s the beauty of these experiments,” said Dr Cimarelli.
“Things that are unconstrainable in nature can be constrained in the lab. And that’s what we did. We changed systematically the sizes of the material we were using and we noticed that if we decreased the grain size of the ash, we produced more flashes.”

Dr Cimarelli’s team is now taking the lessons learned out into the field to study lighting at Sakurajima volcano in Japan. It is the type of volcano that produces regular, spectacular flashes.
The scientists want to test the idea that you could extrapolate ash size from the frequency of lightning events.

“The size of the particles determines the time of residence in the atmosphere and the smaller they are, the longer they stay up to be carried by the winds," said Dr Cimarelli.
"This means, of course, that if you have smaller particles, those particles can be carried long distances. And this is bad news for aviation, which we all know from the Eyjafjallajokull eruption in 2010.”

http://www.bbc.co.uk/news/science-environment-27220909
 
It's the same thing that happens with nuclear bomb explosions.
 
Explosive Eruption at Sangeang Api in Indonesia
BY ERIK KLEMETTI 05.30.14 | 8:34 AM | PERMALINK
.
The eruption column at Sangeang Api, seen on May 30, 2014. Image: Vira Azzukhruf, used by permission.

New reports from Indonesia tell of an sizable explosive eruption that occurred today at Sangeang Api (see above). These news reports suggest ash falling upwards of 30 km from the volcano with a 3 km (10,000 foot) ash plume while the Darwin VAAC warning of the eruption lists ash spotted by pilots as high as 20-50 km (65,000-164,000 feet) as the ash drifts to the southeast. Now, these plume heights are wildly different and some of the images on Twitter suggest the plume is on the closer to the 20 km than 3 km height, but hopefully forthcoming reports will make the actual height clearer to understand.

UPDATE (8:30 AM EDT): Here is a great image of the start of the eruption, with the plume rising rapidly.

The only evacuation orders so far are for people within 1.5 km from the volcano, but luckily no one lives on the island — however, there are many agricultural fields on the small island, so people have been warned to stay away. Apparently seismicity (or explosive shockwaves?) related to the eruption was felt across the city of Bima and nearby Flores as well, suggesting that this is a large explosive event. This explosive eruption would be the first one at Sangeang Api since the volcano’s 1997-99 eruptive period. Looking through its eruptive history, Sangeang Api has produced numerous VEI 2-3 explosive eruptions over the past century. A dome occupies the main crater of the volcano, but only weak steam plumes (~10 meters) and a mix of deep and shallow seismicity have been recorded at the volcano over the past few years.

I will try to update this post as the news rolls in.
http://www.wired.com/2014/05/explosive- ... indonesia/
Click to expand...
 
At least we'll have the amusement of hearing newsreaders try to pronounce its name (or avoid doing so).
 
Iceland Mila Webcams

Incidently, if you want to watch live live, happening right now, webcams of various mountain volcanos in Iceland, this is a great site. I watched the old Eyjafjallajokull, for days with this sites cameras, they had three cameras on the mountain that time.

It was interesting to see not only the eruptions, but also the floods from the melting icecap, that changed the landscape on an ongoing basis day to day. The link above is to Bardabunga, but not much going on at present. It's like watching stones...

Not to mention they have cameras on many other sites around Iceland, waterfalls, geysers, and the like.
 
Tourist films volcano Mount Tavurvur erupting and sending out awesome shockwave

http://metro.co.uk/2014/09/06/touri...ng-and-sending-out-awesome-shockwave-4858865/

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A holiday maker captured the true power of nature when he managed to film incredible footage of a volcano erupting.

Phil McNamara filmed Mount Tavurvur blowing its cap off in Papua New Guinea last week, sending a plume of debris and smoke into the air.

The film even captured a shock wave ripping through the clouds before the sonic boom slams into the tourist boat with a ear splitting bang.

Phil sums up the sight perfectly by saying: ‘Holy smoking Toledos.’

The eruptions on Tavurvur, the most unstable volcano in the area, continued for several days afterwards.

In 1994 Mount Tavurvur erupted with such force that it destroyed half of the nearby city of Rabaul.
 
Waylander28 said:
Looking very active now, three flamers one major, and a lot of vents, opening. This second Bardarbunga Web cam has a good view.
Click to expand...

Do you realise what you've done to me? I'm checking into this site hourly now, lol.

Many Thanks :)
 
Cultjunky said:
Waylander28 said:
Looking very active now.
Do you realise what you've done to me? I'm checking into this site hourly now, lol.

Many Thanks :)
Click to expand...
Click to expand...

:) I know, I keep checking also. Night time Viewing of the Bardabunga 2 camera is a must. Or as I now call it the Cowa-bunga camera.

This happened to me the last time, Eyjafjallajökull, everyday viewing... I was an addict... actually left the Pad on the mantelpiece like a window to Iceland for a whole day once.
 
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