Campi Flegrei Napels: Supervulkaan kan leven Europa in bedreigen

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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:

[..]

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."