Innovative research by the ETH Federal Polytechnic, according to which the volcano overlooking Naples is expected to have a long pause before waking up

Located near Naples, Vesuvio it allowed itself the last violent eruption in 1944, towards the end of the Second World War. However, it could take a few hundred years before another dangerous and explosive gas and lava emission occurs, according to an innovative study by volcanology experts from the Zurich Polytechnic.
Il Vesuvio is one of the most volcanoes dangerous in Europe. More than three million people live in its immediate vicinity, and in historic and prehistoric times, there have been explosive eruptions that have destroyed entire settlements and cities in the area.
So, the pressing question is: when the Vesuvio will it erupt again and how violent could the eruption be?

# 18 March 1944, Vesuvius eruption. More than 12 thousand people were forced to evacuate. The direction of the winds preserved the city of Naples from the cloud of ash and lapilli. Today the volcano is monitored 24 hours a day by the Vesuvian Observatory pic.twitter.com/K7ExdzRtJG

— Civil Protection Department (@DPCgov) March 18, 2020

To answer this question, a research group from the Federal Polytechnic di Zurich, in collaboration with Italian scholars, has closely examined the four largest eruptions of the Vesuvio in the lasts 10.000 years, so that you can better assess whether a dangerous event could be foreseeable in the near future.
The four eruptions studied include that of Avellino di 3.950 years ago, which is considered a possible “worst-case scenario” for future eruptions, and the episode of the 79 after Christ, who famously buried the Roman cities of Pompeii and Herculaneum.
The latter was documented by the Roman writer Pliny the Younger, and so all eruptions of this type are referred to as eruptions "plinian“. In addition, volcanologists have studied the eruptions of 472 after Christ and 8890 before Christ.
The first of these episodes sub-Plinian it is the smallest of the eruptions studied, but would still be similar in size to the recent eruption of Tonga.

There is a drone that "climbs" trees to protect them

Garnet crystals allow for more precise dating

In their study, which was just published in the journalScience Advances”, researchers working with the lead author Jörn-Frederik Wotzlaw and with the professor Olivier Bachmann ofEidgenössische Technische Hochschule Zurich determined the age of garnet crystals present in volcanic deposits.
This mineral grows from magma as it is stored in the magma chamber in the upper crust below the Vesuvio. Knowing the age of these minerals allows us to deduce how long the magma remained in this chamber before the volcano spewed it out.
Garnet is an unusual choice for determining the age of “eject” volcanic. Researchers typically use zircons, which are tiny accessory minerals found in many igneous rocks. The magma of Vesuvio it is too alkaline to crystallize zircons, however it is rich in garnet.
In volcanology, the term “eject” refers to particles and matter ejected from an erupting volcano. The substance can be composed of many different materials, including partially liquid magma and rock.

An unprecedented synthetic plaster to seal internal wounds

From uranium and thorium the age of crystallization of minerals

I "eject” volcanic is sometimes classified according to the size of the samples; extremely fine samples are referred to as “ash”, samples with a diameter of less than 2,5 inches (63,5 mm) They are called "lapilli” and anything larger is referred to as a “block"Or"bomb”, depending on the solidity of the sample. Collectively, the "eject” volcanic is often called “tephra".
To determine the age of the garnets, researchers at theETH they used the radioactive elements uranium and thorium. The crystal structure of garnet incorporates both in small but measurable amounts, with a preference for uranium. Using the uranium-238 to thorium-230 isotope ratio, i researchers can calculate the crystallization age of minerals.
The garnets for this study all come from material that the team's Federal Polytechnic di Zurich has collected on the spot with the help of colleagues from University of Milan and Bari. For this purpose, they searched for the corresponding sites where volcanic deposits from the four aforementioned eruptions are exposed at the surface and accessible for sampling.

In Catanzaro, the innovation hub for the Mediterranean area

The intervals shorten from 4 to about every thousand years

Using the crystallization ages of garnets, researchers can now show that the most explosive type of magma in the Vesuvio (the so-called magma “phonolytic“) is stored in a reservoir in the upper crust for several thousand years before the inflow of more primitive, and hotter, magma from the lower crust triggers an eruption.
For the two prehistoric events, the researchers determined that the magma phonolytic remained in the chamber for approx 5.000 years. Prior to the historical period eruptions, it was only stored in this tank for approx 1.000 years.
For all eruptions, the residence time of the magma phonolytic in the upper crustal chamber it coincides with the quiescent periods of the Vesuvius.
“We think it is likely that a large phonolitic magma body in the upper crust blocked the upwelling of more primitive and hotter magma from deeper reservoirs.”Says Bachmann. “Vesuvius has a fairly complicated hydraulic system”, he adds with a smile.
Below the volcano, there are several magma chambers connected by a system of “tubes”. The upper chamber, which is critical for eruptions, fills with magma from one of the lower chambers in a fairly short amount of time.

In this colder environment, the magma cools and crystallizes, leading to chemical changes of the residual melt (a process called "magmatic differentiation"). Experts call magma “differentiated" of the Vesuvio "phonolite".
At some point (probably at relatively regular intervals), a more primitive magma, or "mafic“, flows into the upper chamber from greater depths.
This recharge leads to an increase in pressure within the chamber, which can force out the magma phonolytic upwards, potentially to the surface, initiating an eruption.
A magma reservoir phonolytic seems to have almost always existed under the Vesuvio in the lasts 10.000 years. However, the question is whether today it can fuel a dangerous eruption like that of 3 years ago or that of 950 after Christ.

Mini electricity generators formed by… quantum dots

Rather unlikely magma accumulation in the reservoir today

Seismic surveys indicate that there is indeed a reservoir at a depth of about six to eight kilometers under the Vesuvio. However, the composition of the magma it contains (that is, whether it is more phonolitic or more mafic) cannot be determined using seismic technology.
Since the Vesuvio mainly produces magma mafic from 1631, the researchers believe it is unlikely that the phonolite waste is currently accumulating.
“The last major eruption in 1944 was almost eighty years ago, which may be the beginning of a prolonged quiescent period during which differentiated magma can accumulate. However, a dangerous eruption, comparable to that of 79 after Christ, probably needs the period of quiescence to last much longer", he adds Wotzlaw.

How to innovate Switzerland's built infrastructure?

“Nothing should actually be present under Vesuvius”

If the magma predominantly mafic should be expelled in the coming decades, this could indicate that the magma body detected by the seismic surveys is not composed of differentiated magma and that nothing is currently present under the Vesuvio.
“That is why we think it is more likely that a large explosive eruption of Vesuvius will occur only after a period of quiescence lasting centuries”Says Bachmann.
Wotzlaw adds: "However, smaller, but still very dangerous eruptions like the one in 1944 or even the one in 1631, could occur after shorter periods of quiescence."
And yet: “An accurate prediction of the size and 'style' of volcanic eruptions is as yet not possible. However, the resurgence of magma reservoirs under the volcanoes are now recognizable thanks to continuous monitoring".

From PSI an unprecedented effective combined treatment of cancer

Close monitoring and an ad hoc plan for evacuations

To avoid nasty surprises, the Vesuvio and its activity, together with its “older brother” further west, i Campi Flegrei, are monitored round the clock.
For example, theItalian National Institute of Geophysics and Volcanology measures each earthquake around the volcanoes, analyzes the gases emitted by fumaroles and observes the deformations of the ground, which are indicators of underground activity.
There is also a contingency plan outlining how to evacuate the greater metropolitan area of Naples if surveillance concludes that an eruption is imminent.

EPFL's "recipe" for more powerful quantum computers