Campi Flegrei Napels: Supervulkaan kan leven Europa in bedreigen

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Op dinsdag 4 januari 2011 10:23 schreef HyperViper het volgende:
Spannend, is deze vergelijkbaar met Toba?

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Op maandag 3 januari 2011 23:20 schreef Honingbijtje het volgende:
Ik hoop stiekem dat ie uitbarst : O

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Op dinsdag 4 januari 2011 10:23 schreef HyperViper het volgende:
Spannend, is deze vergelijkbaar met Toba?

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Op woensdag 21 september 2011 16:43 schreef lipjes het volgende:
Ik ga deze eens even kicken

Viel me op dat er de afgelopen tijd wat krachtige activiteit is:
Date Time Magnitude Depth
2011-09-19 23:27:19 2.3 27 Km
2011-09-17 13:41:44 3.6 23 Km
2011-09-08 22:06:21 4.8 33 Km
2011-09-07 00:10:01 5.0 40 Km
2011-09-06 10:47:28 5.0 25 Km
2011-08-16 19:35:20 5.4 40 Km
2011-08-14 20:42:05 4.9 50 Km
2011-08-09 19:24:33 2.8 8 Km
2011-08-07 20:31:52 3.2 8 Km
2011-08-05 10:53:22 4.9 56 Km

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Op woensdag 21 september 2011 16:57 schreef Frutsel het volgende:
Tambora heeft de alertstatus al verhoogd naar de ena-hoogste stand...

italie rommelt het echt flink door, wist niet dat deze bevingen echt bij CF waren

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Possible signs of magma ascent in supervolcano Campi Flegrei

Campi Flegrei caldera (Italy): increase in uplift and temperature as possible signs of magma ascent

According to a recent report by INGV Naples, the ground deformation of the Campi Flegrei (Phlegraean Fields) near Naples has increased considerably lately. During the last 12 months, the ground in some places near the town of Pozzuoli was uplifted by about 8 cm.
The largest uplift, recorded by GPS devices, occurred during the months of July-August 2012 and since December. The trend appears to be continuing at the moment.

Such (sometimes dramatic, totaling up to several meters in a few years) ground uplift and subsidence have been known in the Phlegraean Fields since antiquity and are not a new phenomenon. They can usually be explained by normal pressure, temperature and density variations of the giant hydrothermal system of the Campi Flegrei caldera and may not necessarily indicate an imminent eruption.

However, in addition to the detected ground deformation, scientists also measured increased numbers of micro earthquakes, a rise in temperature and in particular, an increase in the proportion of the gases of magmatic origin at fumaroles in the Solfatara crater.

As the hydrothermal system is closely connected with the underlying complex magma chamber of the Phlegrean Fields, new magma movements could in fact be the culprit for the observed changes. Whether these, and if so when, will lead to a new volcanic eruption is currently uncertain.
A much larger increase of such observed changes should probably be expected if in fact should new volcanic activity was to announce itself.

The last volcanic eruption occurred after a rest period of about 3000 years in the year 1538 AD and built a new cinder cone, the Monte Nuovo ("New Mountain") near Pozzuoli.

Strong ground uplift, earthquakes and changes in springs and fumaroles preceded the eruption according to historical sources. Even though it was - geologically speaking - a rather small eruption, the effects of a similar event today would be devastating for the very densely populated area. It should be hoped that the residents and all involved are spared such a scenario, at least for the near future.

Ancient Supervolcano's Eruption Spewed Ash Over Europe, Asia | Video

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Supervolcano awakening in Italy?
It looks like we may be in for an earth-shattering explosion. A dormant super volcano appears to be stirring under the Phlegraen Fields of Naples in Italy. Rising soil temperatures and surface deformation in the area have alarmed seismologists. In the distant past, volcanic super eruptions caused global climate change responsible for mass extinctions of plant and animal species.

So far, scientists are unable to model the potential consequences of an awakening super volcano.

Latest studies show that the Phlegraen Fields have actually been swelling above sea level at a rate of 3 cm per month. Micro quakes and large amounts of gases accumulated in soil indicate that the volcano may be preparing to erupt, says Vladimir Kiryanov, Assistant Professor of Geology at the St. Petersburg University.

"The Phlegraen Fields are a super volcano. Yellowstone in the United States and Toba in Indonesia are also super volcanoes capable of spewing more than 1,000 cubic km of magma. These are catastrophic eruptions. There was a huge volcanic eruption in the Phlegraen Fields some 30,000-40,000 years ago. Volcanic ash from that eruption is still found in the Mediterranean, Bulgaria, Ukraine, and even in Russia. We are now seeing the expansion of a magma pocket, which means that there might be an eruption at a certain time."

Super eruptions of such magnitude may produce the so-called “volcanic winter” effect when sulfur gases and ash will reach the stratosphere and cover the globe with thick ash clouds that solar rays will be unable to penetrate. Condensed sulfur trioxides will react with moisture, forming sulfuric acid. Downpours of sulfuric acid will hit the Earth. Scientists have obtained new evidence of a similar cataclysm following the eruption of the Toba super volcano on island of Sumatra in Indonesia about 74,000 years ago. But today, things promise to be even more devastating. Suffice it to recall the havoc wreaked by a minor increase in volcanic activity in Iceland in 2010 on air transportation over Europe.

Super eruptions occurred so rarely that it is virtually impossible to calculate the approximate time span between the first and last stages of a future potential eruption. In the 1970s, the Phlegraen Fields inflated by more than 50 cm. There were even cracks in house walls. But then the process slackened. Apparently, the fact itself that a magma chamber is being filled with magma may or may not signal any immediate eruption. Alexei Sobisevich, laboratory chief at the Institute of Volcanology and Geophysics of the Russian Academy of Sciences, shares his view:

"It actually seems to be a long-term precursor. A magma chamber may be filled up within a span ranging from decades to centuries. Many mounts grow by 5 cm per year. This is a natural process."

Some scientists hold that the volcanic system of the Earth is becoming increasingly tense and that underground cavities are full of magma threatening to burst out any moment. Whether this will be a super eruption or a string of smaller eruptions, we should prepare for the worst.

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Campi Flegrei nearing critical pressure point
The slumbering Campi Flegrei volcano under the Italian city of Naples shows signs of reawakening and may be nearing a critical pressure point, according to a new study.

Italian and French scientists have for the first time identified a threshold beyond which rising magma under the Earth’s surface could trigger the release of fluids and gases at a 10-fold increased rate.

This would cause the injection of high-temperature steam into surrounding rocks, said Giovanni Chiodini, a researcher at Italy’s National Institute of Geophysics and Volcanology in Bologna. “Hydrothermal rocks, if heated, can ultimately lose their mechanical resistance, causing an acceleration towards critical conditions,” he told AFP by email.

He said it was not possible to say when – or if – the volcano would erupt but “it would be very dangerous” if it did for about 500,000 people living inside and near the caldera – the bowl-like depression created after a volcano blows its top.

Chiodini said there was an urgent need to obtain a better understanding of Campi Flegrei’s behaviour because of the risk to such a dense urban population.

Since 2005, Campi Flegrei has been undergoing what scientists call uplift, causing Italian authorities to raise the alert level in 2012 from green to yellow, signalling the need for active scientific monitoring. The pace of ground deformation and low-level seismic activity has recently increased.

Two other active volcanoes – Rabaul in Papua New Guinea and Sierra Negra in the Galapagos – “both showed acceleration in ground deformation before eruption with a pattern similar to that observed at Campi Flegrei,” Chiodini said.

The Campi Flegrei caldera was formed 39,000 years ago in an explosion that threw hundreds of cubic kilometres of lava, rock and debris into the air in the largest eruption in Europe in the past 200,000 years. Campi Flegrei last erupted in 1538, though on a much smaller scale.

Nearby Mount Vesuvius, which had a massive eruption in AD79 that buried several Roman settlements including Pompeii, is also classified as an active volcano.

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Op woensdag 21 december 2016 08:55 schreef Frutsel het volgende:
Vulkanologen: 'monster van Napels' kan rond 2020 ontwaken

Een van de engste vulkanen van Europa lijkt af te stevenen op een eruptie. Ergens rond 2020 zou de reuzenvulkaan Campi Flegrei bij Napels zijn kookpunt bereiken en tot uitbarsting kunnen komen. Dat becijferen Italiaanse vulkanologen aan de hand van gassen die uit de vulkaan ontsnappen.

Voor de rest: lees hier

[..]

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Op woensdag 21 december 2016 08:59 schreef IJsmuts het volgende:
nog ff snel napels zien en dan sterven.

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Op maandag 3 januari 2011 23:26 schreef ikbennieuwopfok het volgende:
Nog minder dan 2 jaar.

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Op vrijdag 23 december 2016 21:28 schreef DemonRage het volgende:
Dit bloed maar in de gaten houden dan...

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Op maandag 15 mei 2017 22:34 schreef Frutsel het volgende:
https://m.phys.org/news/2(...)uption-possibly.html


Nieuw artikel? Maar weinig nieuws?

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Op maandag 22 mei 2017 06:23 schreef de_tevreden_atheist het volgende:
https://www.wired.com/201(...)italys-supervolcano/

Wanneer geef je als burgemeester van Napels het bevel tot evacuatie van 5 miljoen mensen, en wanneer beslis je of het loos alarm was zodat ze weer terug kunnen keren?

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Italiaans gezin komt om in vulkaangebied

De kisten waarin de slachtoffers worden weggedragen komen aan EPA
In het zuiden van Italië heeft zich bij de vulkaan Solfatara een gezinsdrama voorgedaan. Een jongen van elf klom over een hek een verboden gebied in en viel, waarschijnlijk in een krater. Zijn ouders probeerden hem te redden maar kwamen daarbij zelf om. Een broertje van zeven dat buiten de verboden zone was gebleven was getuige van het drama.

Wat de drie slachtoffers het leven heeft gekost is nog niet duidelijk. Mogelijk zijn ze onwel geworden door gassen in de krater of zijn ze omgekomen door een explosie van hete modder, vlak onder oppervlakte van de krater. De overvloedige regenval van de afgelopen dagen heeft geleid tot meer openingen in de oppervlakte van de vulkaan.

Brandende Velden

De Solfatara-krater is onderdeel van de Campi Flegrei, ofwel de Brandende Velden. De laatste eruptie was in 1198. Tegenwoordig ontsnappen regelmatig rookslierten en er doen zich van tijd tot tijd aardschokken voor. De temperatuur kan plaatselijk oplopen tot 160 graden.

Kenmerkend voor deze vulkaan zijn de fumarolen, openingen in de vulkaan waarbij de uitgestoten gassen grotendeels uit waterdamp bestaan. De overige componenten zijn ijzerverbindingen en zwavelverbindingen.

De Brandende Velden zijn een toeristische attractie in de regio Napels. De velden worden ook veel bezocht door schoolklassen. Door het hele gebied staan waarschuwingsborden en gevaarlijke stukken zijn door hekken omsloten.

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Scientists locate potential magma source in Italian supervolcano

Scientists have now pinpointed the location of the hot zone where hot materials rose to feed the caldera during its last period of activity in the 1980s. Credit: University of Aberdeen
Scientists have found the first direct evidence of a so-called 'hot zone' feeding a supervolcano in southern Italy that experts say is nearing eruption conditions.

Campi Flegrei is a volcanic caldera to the west of Naples that last erupted centuries ago.
The area has been relatively quiet since the 1980s when the injection of either magma or fluids in the shallower structure of the volcano caused a series of small earthquakes.
Using seismological techniques, scientists have now pinpointed the location of the hot zone where hot materials rose to feed the caldera during this period.

The study was led by Dr Luca De Siena at the University of Aberdeen in conjunction with the INGV Osservatorio Vesuviano, the RISSC lab of the University of Naples, and the University of Texas at Austin. The research provides a benchmark that may help predict how and where future eruptions could strike.

"One question that has puzzled scientists is where magma is located beneath the caldera, and our study provides the first evidence of a hot zone under the city of Pozzuoli that extends into the sea at a depth of 4 km," Dr De Siena said.

"While this is the most probable location of a small batch of magma, it could also be the heated fluid-filled top of a wider magma chamber, located even deeper."

Dr De Siena's study suggests that magma was prevented from rising to the surface in the 1980s by the presence of a 1-2 km-deep rock formation that blocked its path, forcing it to release stress along a lateral route.

While the implications of this are still not fully understood, the relatively low amount of seismic activity in the area since the 1980s suggests that pressure is building within the caldera, making it more dangerous.

"During the last 30 years the behaviour of the volcano has changed, with everything becoming hotter due to fluids permeating the entire caldera," Dr De Siena explained.

"Whatever produced the activity under Pozzuoli in the 1980s has migrated somewhere else, so the danger doesn't just lie in the same spot, it could now be much nearer to Naples which is more densely populated.

"This means that the risk from the caldera is no longer just in the centre, but has migrated. Indeed, you can now characterise Campi Flegrei as being like a boiling pot of soup beneath the surface.
"What this means in terms of the scale of any future eruption we cannot say, but there is no doubt that the volcano is becoming more dangerous.

"The big question we have to answer now is if it is a big layer of magma that is rising to the surface, or something less worrying which could find its way to the surface out at sea."

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Op maandag 18 september 2017 22:15 schreef Frutsel het volgende:

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Wot ?

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Magma building beneath dangerous supervolcano could signal huge eruption
One of the world’s most dangerous supervolcanoes appears to be accumulating magma as it transitions to a pre-eruption state, a study has found. Scientists do not say that a large eruption is imminent—but they do suggest that current conditions at Campi Flegrei indicate one could happen at "some undetermined point in the future."

Campi Flegrei is one of the few active supervolcanoes in the world. It is located in southern Italy, about nine miles to the west of Naples, which is home to around 1.5 million people. The last time it erupted was in 1538—a fairly small event known as the Monte Nuovo eruption. However, 40,000 years ago, it produced a "super-colossal" eruption, which is just one down from the “mega-colossal” eruptions recorded at Yellowstone.

Over the last 60 years, the volcanic region—which is made up of 24 craters and edifices—has shown signs of unrest, and scientists have been studying it and monitoring it closely to better understand the changes taking place.

In a study published in Science Advances, a team of researchers led by Francesca Forni, from ETH Zurich in Switzerland, examined rock, mineral and glass samples taken from 23 eruptions at Campi Flegrei—including the two biggest from the last 60,000 years. By analyzing the elements within these samples, the researchers were able to construct a picture of what was happening before and after eruptions.

Their findings appear to show that magma is building beneath the volcanic system—and that it is entering a new caldera cycle. This could indicate that the volcano is moving toward a new phase that will result in a large eruption at the site, the team says. The study does not indicate that an eruption will happen soon.

Analysis of the elements suggest there were critical changes to the temperature and water content of the magma at certain points in the eruptive history of Campi Flegrei. Minerals in the magma were found to decrease over time, while water content increased. They found that this happened before the Monte Nuovo eruption.

The team notes that after the Monte Nuovo eruption, Campi Flegrei entered a “new phase” of inactivity. Since the 1950s, there have been three “major periods of unrest,” raising concern that the volcano is reawakening. The movement of magma from depths of about five miles to 1.8 miles has previously been blamed for this unrest.

The latest findings suggest this is consistent with the presence of water-saturated magma in the upper crust, allowing for the build up of a huge magma reservoir. “We propose that the subvolcanic plumbing system at Campi Flegrei is currently entering a new build-up phase, potentially culminating, at some undetermined point in the future, in a large volume eruption,” they conclude.

Luca De Siena, from the U.K.’s University of Aberdeen, who has previously published research on the Campi Flegrei system, commented on the findings: “At Campi Flegrei, an outstanding question is why we cannot see the plumbing systems of the volcano below 4-5km (2.5-3 mile) depths, as at Yellowstone caldera, for example,” he told Newsweek.

“Forni et al. suggest that a large, highly-evolved, and relatively cold magma layer may be absorbing most of the energy we send down to reconstruct deeper structures. This problem is typical of sub-basaltic, oceanic settings, where deeper reservoirs are invisible to seismic imaging. Their findings open the possibility to model the effects of these magmatic layers on monitoring recording, thus allowing to reconstruct their shape and dimensions and eventually see below them.”

Volcanologist Christopher Kilburn, from the U.K.'s UCL, who was also not involved in the study, said the results are consistent with observed changes that took plalce during past eruptions: "It thus provides an alternative interpretation to be tested against conventional ideas," he said.

"Should an eruption occur, the best guess is that it will have a size and behaviour similar to that seen during past 15,000 years or so--hence ranging from the size of the last eruption (Monte Nuovo, 1538, 0.02 cubic km) to something similar to the eruption of Vesuvius that overwhelmed Pompeii and Herculaneum (c. one cubic km). These are the scenarios being used to prepare mitigation plans.

"The paper changes tack in its final paragraph. Having argued that the 1538 eruption represents the squeezing out of magma from the vestige of a magma reservoir, it suggests that CO2 emissions indicate the possible replenishment of the reservoir and, thus, hints at the possible start of a build-up to a 'large-volume eruption.' This statement is speculative and does not depend on the preceding results."