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General Volcanic Activity Thread!

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MVO reports

Activity at the Soufrière Hills Volcano has been low this week.

There have been seven rock fall signals, two long period, one hybrid and three volcano tectonic earthquakes recorded this week.

Several rockfalls occurred on the western side of the lava dome on 15 April and a small pyroclastic flow occurred on the Gages fan on 16 April. These were probably caused by the heavy rainfall this week causing small amounts of destabilisation on the remaining parts of the lava dome.

The average sulphur dioxide flux measured for five days this week was 400 tons per day, with a daily minimum of 242 and a maximum of 530 tons per day. Fourier Transform infrared measurements on the 9 April gave a hydrochloric acid /sulphur dioxide ratio of 0.45.

Heavy rain this week has generated lahars (mudflows) on several flanks of the volcano. On afternoon of 13 April large lahars occurred in the Belham valley. Many of these lahars were hot with abundant steam and geyersing associated with them. Two large fans were formed at the coast of Old Road Bay as a result of these events. These were the largest lahar events to have occurred since November 2009.

The Hazard Level is 3. There is no access to the terrestrial Zone C and daytime transit access to shipping through the maritime extension of the zone.

Source http://www.mvo.ms/

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Santa Marie has had a little pop from the lava dome complex growing at the base of the 1902 eurption crater.

As has already been reported on the excellent Volcanism Blog, Santiaguito experienced a large eruption yesterday morning. Here's a translated announcement that made its way to me from Gustavo Chigna of the Instituto Nacional de Sismología, Vulcanología, Meteorología e Hidrología (INSIVUMEH):

This morning at 06:50 to 09:45 Santiaguito entered a volcanic eruption with 4 face of crater collapses and pyroclastic flows generated within the gullies on the southern flank. The ash column reached heights of 27,000 feet in a westerly direction, northwest and north, forcing the closure of village schools southwest of Santiaguito and in the Quetzaltenango area. A similar eruption to this has not been seen since 1989. The ash is still scattered at 24,000 feet and civil aeronautics alerted air traffic to avoid the plume within a radius of 80 km.

If you haven't seen my earlier posts on Santiaguito (my study area), here's a little background: The Santiaguito lava dome complex is a set of four lava domes at the base of the now inactive Santa Maria Volcano. Currently only one of the domes (El Caliente) is active, and this is the site of yesterday's eruption. Typically, activity on Caliente is limited to 1-3 km high ash-and-gas explosions every hour or two, accompanied by the extrusion of a blocky lava flow from Caliente's summit, occasional pyroclastic flows, and almost continuous rockfalls. Yesterday's event appears to have been quite a bit larger than the usual activity, and has disrupted life for the people living near the domes.

The last eruption at Caliente of this magnitude occurred in 1989, and produced similar ashfall and pyroclastic flows in the drainages on the south side of the domes. Before that, there was the 1973 event, a large collapse and pyroclastic flow from the Brujo lava dome (the last dome to the west of Caliente). Brujo is no longer erupting today, although there is some fumarolic (mostly water vapor) activity. (For more information on the 1973 event, have a look at this paper: Rose, W.I., 1973, Nuée ardente from Santiaguito volcano, April 1973: Bulletin of Volcanology, v. 37, p. 365-371.)

Dealing with ashfall isn't very fun, as folks in Europe can attest, since it gets into everything and makes breathing uncomfortable, if not difficult. On my last field excursion to Guatemala, we were lucky to be out of the way of the ash plume from Caliente - the prevailing winds kept it blowing in the opposite direction of our camp. I'm also quite glad that this event occurred after we were off the domes, because it might have meant dealing with major ashfall at the least, and possibly pyroclastic flows from the column collapse.

Source http://magmacumlaude.blogspot.com/2010/04/large-santiaguito-eruption-yesterday.html

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Meanwhile rumours are circulating that Ischia may be getting charged up. However seismic activity doesn't back this up. http://www.huffingtonpost.com/huff-wires/20100427/eu-italy-volcanoes/

There's also speculation that long running eruption at Kilauea may be slowing down and coming to an end. This is based on the reduction of sulphur rates that are at lowest for some time. However I'm not so sure as inflation is taking place on the northern flank of Pu`u `O`o. The drop in gas maybe due to the eruption at the summit of the volcano allowing gas free magma to erupt in the east rift zone.

Now here are some idiots

part two

very lucky to be alive.

Edited by The PIT

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Well as everything goes quiet in Iceland mount Cleveland is waking up http://newsminer.com/view/full_story/7662284/article-Alert-level-raised-for-Alaska-volcano-?instance=home_news_window_left_bullets

Today it wasn't doing much but two days ago things were more interesting

Thermal anomalies observed in satellite data over the past few days suggest that Cleveland Volcano has entered another period of volcanic unrest. In the past, the presence of thermal anomalies at the summit has been followed by moderate ash bursts, sometimes to aircraft flight levels. Therefore, AVO is raising the Aviation Color Code to YELLOW and the Volcano Alert Level to ADVISORY.

The lack of a real-time seismic network at Cleveland means that AVO is unable to track local earthquake activity related to volcanic unrest. Unrest at Cleveland is frequent, and short-lived explosions with ash clouds or plumes that could exceed 20,000 ft above sea level can occur without warning and may go undetected on satellite imagery.

Other matters Kilauea reached 10,000 days of eruption on the 22nd and is still chugging away. It worth looking at the table seeing how big this eruption is http://hvo.wr.usgs.gov/kilauea/history/historytable.html. There's no sign of it stopping any day soon either.

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Beat me to it.

As of the 30th of May, the National Institute Of Sismología, Volcanology, Meteorology And Hidrologia, (INSIVUMEH) has reported that Pacaya volcano erupted on Thursday, the 27th of May, so those explosive eruptions shook two huge volcanos in Central and South America on Friday, forcing thousands of people to flee their homes and disrupting air traffic as ash drifted over major cities. Guatemala's Pacaya volcano started erupting lava and rocks Thursday afternoon, blanketing the country's capital with ash and forcing the closure of the international airport. A television reporter was killed by a shower of burning rocks when he got too close to the volcano, about 15 miles (25 kilometres) south of Guatemala City. In the village of Calderas, close to the eruption, Brenda Castaneda said she and her family hid under beds and tables as marble-sized rocks thundered down on her home. "We thought we wouldn't survive. Our houses crumbled and we've lost everything," Castaneda said while waiting for rescue teams to take them to a shelter at a nearby school.

Meanwhile, strong explosions rocked Ecuador's Tungurahua volcano, prompting evacuations of hundreds of people from nearby villages. Ecuador's National Geophysics Institute said hot volcanic material blasted down the slopes and ash plumes soared 6 miles (10 kilometres) above a crater that is already 16,479 feet (5,023 metres) above sea level. Winds blew the ash over the country's most populous city, Guayaquil, and led aviation officials to halt flights out of the Pacific port and from Quito to Lima, Peru. Neither of the eruptions was expected to disrupt airports in neighbouring countries like Iceland's Eyjafjallajokul volcano did in Europe. In Guatemala, the ash billowing from Pacaya has been thick and falls quickly to the ground, unlike the lighter ash that spewed from the volcano in Iceland and swept over much of Europe, disrupting global air travel, said Gustavo Chigna, a volcano expert with Guatemala's institute of seismology and volcanoes. In Ecuador, the ash cloud drifted out over the Pacific Ocean and was tapering off Friday evening.

In Guatemala, at least 1,910 people from villages closest to the Pacaya volcano were moved to shelters. Some 800 homes were damaged in the initial eruption late Thursday. A second eruption at midday Friday released ash in smaller amounts from the 8,373-foot (2,552 metres) mountain, according to the Central American country's Geophysical Research and Services Unit. The unit reported an ash plume 3,000 feet (1,000) metres high that trailed more than 12 miles (20 kilometres) to the northwest. In Guatemala City, bulldozers scraped blackened streets while residents used shovels to clean cars and roofs. The blanket of ash was three inches (7.5 centimetres) thick in some southern parts of the city. The government urged people not to leave their homes unless there was an urgent need. The capital's La Aurora airport would be closed at least until Saturday, said Claudia Monge, a spokeswoman for the civil aviation agency. Flights were being diverted to Mundo Maya airport in northern Guatemala and Comalapa in El Salvador.

President Alvaro Colom told a news conference that three children aged 10, 9 and 7 were missing after the eruption. Colom declared a state of emergency for the area near the volcano, which is 25 miles (40 km) from Guatemala City. Civil aviation authorities closed the country's main La Aurora international airport. "The sand is falling on the runway and we need to clear it before any planes can land for safety reasons," said Monica Monje of Guatemala's aviation authority. Monje said officials would decide whether it was safe to reopen the airport by midday on Friday. Pacaya, which is near Antigua where some of Guatemala's highest quality coffee is grown, has been continuously active since the 1960s but has not showered the surrounding area in small rocks and ash since 1998.

Source http://www.intlvrc.org/news.htm#pacaya

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Printer friendly version Kamchatkan and Northern Kuriles Volcanic Activity

KVERT INFORMATION RELEASE 25-10

Monday, May 31, 2010, 20:45 UTC (June 01, 08:30 KDT)

BEZYMIANNY VOLCANO: 55°58'N, 160°36'E; Elevation 2,882 m

CURRENT AVIATION COLOR CODE IS RED

PREVIOUS AVIATION COLOR CODE WAS ORANGE

A strong explosive eruption of Bezymianny volcano occurred from 12:34 till 12:50 UTC on May 31, according to seismic data. Ash fall in Kozyrevsk village is continuing. The volcano obscured by clouds.

A big ash cloud remains over Kamchatka at present (NOAA-15, 17:52 UTC on May 31, last satellite): coordinates on the south - 56.04 N; the north - 56.94 N; the east - 161.05 E; and all Kamchatka to the west.

The activity of the volcano could affect international and low-flying aircraft.

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Taal Philippines.

The volcano is showing signs of unrest and the Volcano alert has been raised too level 2. Due to the Volcano being in a lake it can produce large and dangerous explosive eruptions with pryoclastic flows and base surges. The last eurption was in 1977 but it's been restless most of the ninenties.

The alert level is now at 2 signs of magma approaching the surface.

Just in case it goes here's some web cam links http://www.getwet-asia.com/philippines/?p=309

Popocatepetl also known as the smoking mountain or El Popo produced an Eruption to 27,000 ft on the June the 8th. Since 1994 the Volcano has being producing small lava domes which are destroyed by small explosive eruptions. Basically the volcano is displaying what is called an open vent style of Eruption where gases are generally free to escape preventing a build up of pressure hence no major eruptions.

Edited by The PIT

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MVO website has the following update

Starting on 25 June 2010, mild ash venting has been occurring from Soufriere Hills volcano.

This is the first time such activity has been seen since February this year. A light dusting of ashfall has been experienced in several places across the island. The onset of the ash venting was coincident with small swarms of volcano tectonic earthquakes that occurred, on 23 and 25 June.

Initial observations by MVO staff showed that venting was taking place from inside the collapse scar, at about the location of English's crater. An observation flight with the helicopter of 'HMS Manchester' on Saturday 26 June revealed that the ash venting was also occurring from the southern part of the crater formed on 11 February.

Audible roaring, associated with the venting was heard from several locations on the island on the nights of 25 and 26 June.

It is unclear what the significance of this venting is; apart from the short swarms of VT earthquakes on Friday 25 June, there is no discernable seismicity associated with the venting. It is possible that this venting is phreatic in nature, related to groundwater interacting with hot material below the surface. There has been a lot of heavy rainfall experienced recently. However, VT earthquakes are often associated with the extrusion of lava, and similar activity has been observed just prior to lava extrusion, such as in 2008.

So it could be another spell of dome growth too come.

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http://www.volcano.si.edu/reports/usgs/

Fair bit of new activity, though nothing major.

Have also been looking at information regarding Vesuvius, and according to statistical models there is already over a 50% chance of an eruption within the next year. Currently a VEI4 eruption is favoured (strongest since 1631), with VEI3 and VEI5 have equal less faviourate percentages. Minimum death toll would be 300,000 due to the fact that a pyrochlastic flow would take just 15 minutes to reach the red zone where the casualties are expected to occur. Truly terrifying statistics. As it is, no recent sysmic activity.

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Unlikely to be an Eruption of Vesuvius in the near future and studies of it's past cycles suggest it maybe going for a fairly long sleep. If it did erupt next year it's unlikely to be as large as the 1631 eruption. The volcano is quiet however the number of people living on the slopes is a concern and any emergency plans to remove them quickly aren't likely to work very well. However the volcano does announce it's awakening fairly well. They were plenty of warning earthquakes before AD79 and the volcano is well monitored.

I don't expect the volcano too erupt in my lifetime and I wouldn't be surprised if it slept for another 300 or 400 years.

Another thing to remember the longer it sleeps the bigger the eruption.

There's another volcano in Italy that was thought to be extinct until fairly recently and if that did erupt that would cause more problems for Italy.

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Unlikely to be an Eruption of Vesuvius in the near future and studies of it's past cycles suggest it maybe going for a fairly long sleep. If it did erupt next year it's unlikely to be as large as the 1631 eruption. The volcano is quiet however the number of people living on the slopes is a concern and any emergency plans to remove them quickly aren't likely to work very well. However the volcano does announce it's awakening fairly well. They were plenty of warning earthquakes before AD79 and the volcano is well monitored.

I don't expect the volcano too erupt in my lifetime and I wouldn't be surprised if it slept for another 300 or 400 years.

Another thing to remember the longer it sleeps the bigger the eruption.

There's another volcano in Italy that was thought to be extinct until fairly recently and if that did erupt that would cause more problems for Italy.

There are actually a fair few volcanoes on the Italian mainland, however other than Vesuvius i do not think there has been an eruption in about 500 years.

In regards to the strength of an eruption being correlated to how long Vesuvius is dormant, yes the link at Vesuvius is actually stronger than most, here is a quote from wikipedia for Vesuvius..

Large plinian eruptions which emit magma in quantities of about 1 cubic kilometre (0.24 cu mi), the most recent of which overwhelmed Pompeii, have happened after periods of inactivity of a few thousand years. Subplinian eruptions producing about 0.1 cubic kilometres (0.024 cu mi), such as those of 472 and 1631, have been more frequent with a few hundred years between them. Following the 1631 eruption until 1944 every few years saw a comparatively small eruption which emitted 0.001-0.01 km³ of magma. It seems that for Vesuvius the amount of magma expelled in an eruption increases very roughly linearly with the interval since the previous one, and at a rate of around 0.001 cubic kilometres (0.00024 cu mi) for each year. This gives an extremely approximate figure of 0.06 cubic kilometres (0.014 cu mi) for an eruption after 60 years of inactivity.[64]

Looking at that, we have 66 years of inactivity which would normally correlate to a VEI 3 eruption, here is an interesting fact for you all, assuming that Vesuvius does not erupt before 2014, it will of been dormant for the longest period since 1347.

In regards to when it will blow, no body knows for sure, however scientists believe that every time an earthquake occurs it transfers pressure to another area along the fault, as evidenced by the Spanish quake in 2008 and subsequent eruption of Stromboli after monitered earthquakes progressing along the fault (also saw earthquakes at Vesuvius a few days after indicating magma movement. With that in mind, i think the best thing for us is to see another quake near Spain/North Africa, if Etna or Stromboli do not go, this could give the required pressure to Vesuvius.

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Can't find any eruption record of 1347. However the records are rather dodgy during that period. Certainly no eruptions after 1500 until 1631. It's also possible there was a repose of nearly 400 yrs before ad79 so we're well within the time period. One problem is that small eruptions would be difficult to isolate so there could well have been activity in that period.

This is the other one that has been creating a bit of interest. http://boris.vulcanoetna.it/ALBANI.html

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http://www.volcano.si.edu/world/volcano.cfm?vnum=0101-02=&volpage=erupt

While there obviously are'nt as detailed records until after the 79AD eruption, looking at its known eruptive history, it seems that Vesuvius began erupting much more frequently around the time that Santorini blew its self apart, since then eruptions have become more and more frequent which is why the current gap of 66 years is concerning to scientists and is why i do not believe that we will see as bigger gap before the next eruption, though you are correct that there was a gap of 297 years before the 79AD eruption. In regards to the 1347 eruption, it is in the link above, and the gap of 153 years before the 1500 eruption is the largest since the AD79 eruption, however considering the frequent activity of the past 500 years, i am more inclined to believe that it will not wait that long, there was also an eruption in 1570.

The volcanoe in the link is certainly noteworthy, while it is quite an old volcano the swarms of earthquakes and uplift certainly do warrant investigation, though i have not been able to find anything more recent than the late 1990's.

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Problem is with the 1347 eurption it's not mentioned in other articles and also listed as doubtful.

At the moment the seismic activity is low although a surprise is possible.

List of eruptions from this site http://www.vesuvioinrete.it/e_storia.htm

Santorini is also a very interesting volcano which if my memory serves me correctly sits on two faults one of which seems linked with the bigger eruptions.

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Problem is with the 1347 eurption it's not mentioned in other articles and also listed as doubtful.

At the moment the seismic activity is low although a surprise is possible.

List of eruptions from this site http://www.vesuvioinrete.it/e_storia.htm

Santorini is also a very interesting volcano which if my memory serves me correctly sits on two faults one of which seems linked with the bigger eruptions.

In regards to Santorini, the fault system is quite strange there because its actually one fault line that does a loop the loop with the confluence in the Agien Sea. In regards to any activity at Santorini, it seems to have entred a more regular eruptive phase in 1570, with the biggest gap in activity being 166 years since then, so with the last eruption having occured in 1950, i would say its pretty certain that another eruption will occur within the next century.

Having had a look around, i think the best chance of an eruption at one of the Greek volcanoes or Vesuvius will occur when the Anatonian fault ruptures at Istanbul, there is a 65% chance of a large earthquake occuring by 2030..

"We know the place. We just don't know exactly when, but there's a 65% probability that Istanbul will be hit by a 7.6 earthquake by 2030. That's a very high probability."

Once that occurs, the pressure will shift along the fault line, either for another earthquake, or to be released by one of the Greek/Italian volcanoes, however equally we could have a large earthquake from the other end of the fault.

Edit: I don't want to be a doom monger here, but read the follwoing quote..

"Since the disastrous Erzincan earthquake in December 1939 in eastern Turkey, there have been six earthquakes along the fault with a magnitude greater than seven points, all progressing from east to west. The most recent, in 1999, was less than 60 miles east of Istanbul."

Correct me if i am wrong but that is one every ten years and the last one occured eleven years ago.

Edited by summer blizzard

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In regards to Santorini, the fault system is quite strange there because its actually one fault line that does a loop the loop with the confluence in the Agien Sea. In regards to any activity at Santorini, it seems to have entred a more regular eruptive phase in 1570, with the biggest gap in activity being 166 years since then, so with the last eruption having occured in 1950, i would say its pretty certain that another eruption will occur within the next century.

Having had a look around, i think the best chance of an eruption at one of the Greek volcanoes or Vesuvius will occur when the Anatonian fault ruptures at Istanbul, there is a 65% chance of a large earthquake occuring by 2030..

"We know the place. We just don't know exactly when, but there's a 65% probability that Istanbul will be hit by a 7.6 earthquake by 2030. That's a very high probability."

Once that occurs, the pressure will shift along the fault line, either for another earthquake, or to be released by one of the Greek/Italian volcanoes, however equally we could have a large earthquake from the other end of the fault.

Edit: I don't want to be a doom monger here, but read the follwoing quote..

"Since the disastrous Erzincan earthquake in December 1939 in eastern Turkey, there have been six earthquakes along the fault with a magnitude greater than seven points, all progressing from east to west. The most recent, in 1999, was less than 60 miles east of Istanbul."

Correct me if i am wrong but that is one every ten years and the last one occured eleven years ago.

Interesting fault line. You've got to remember events like this don't run like clockwork and there will be variations. Like people expected Katla to go boom after the recent eruption of the volcano you can't pronounce. So far it hasn't.

Nature likes to very but it's a case of watching. Unfortunately earthquakes don't give much notice and scientists can only guess when the build up of strain reaches the critical point.

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Interesting fault line. You've got to remember events like this don't run like clockwork and there will be variations. Like people expected Katla to go boom after the recent eruption of the volcano you can't pronounce. So far it hasn't.

Nature likes to very but it's a case of watching. Unfortunately earthquakes don't give much notice and scientists can only guess when the build up of strain reaches the critical point.

True, though pressure has been proven to shift along faults, the only problem being that it needs to find a weak spot to escape. If the Anatonian fault goes then pressure will most likely escape from a Greek/Italian volcano, but if the block is too strong at Santorini or Vesuvius, then it will probably escape from Etna or Stromboli given the usual frequency or eruptions there. In regards to Kalta, i don't actually exect anything serious until the unpronouncable shuts down completely, because at the moment, Katla does not have enougth pressure underneath it imo.

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Over at eruptions there's a series about Etna. A good read part1 up now http://scienceblogs.com/eruptions/

Very interesting, it sounds to me as if Etna will give more of the same for the next 50,000 years or so (a mixture of Lava and explosive eruptions), before it begins a pattern of more and more violent eruptions as the African plate moves north and increases the pressure upon Etna.

If you ask me, the casue of Etna is a combination of hot spot and continental building. Ordinarily, the continental merge of Africa and Europe would normally lend itself to a mountain range rather than a Volcanic system, however becasue Europe is moving east, rather than south, becasue the plate curves around Italy, there is a hot spot forming as subduction occurs, the effect of Africa also moving north is casuing increased pressure, which over time will casue more and more powerful eruptions. In summary, i believe that reason scientists are struggling to understand why a hotspot is present when it should not be (Africa would have to be moving south for that to occur), is because they are not taking into account the shape of the Meditaranian plate around Italy where it becomes W/E rather and N/S, a good anologue to look at for me would probably be the Carribean plate, which also kind of bent and developed from the Pacific/Atlantic cristal zone, if i am correct, then eventually the palte over Italy will evetually be locked once Africa hits Europe.

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Thanks to the parents of one of our visiting English language Students, I have a lovely little book which may interest readers here:

Known and little-known Volcanoes of the Massif Central

Photos  Francis Debaisieux, Design Mireille Debaisieux, Text Noel Graveline ISBN 978-2-913381-13-1 en anglais reimprime en avril 2007.

The last eruptions in France occurred only 7,000 years ago, and the region could become active again. The majority of  recent eruptions in France were brief, and dormancy, rather than extinction is presumed. The book shows some wonderful scenery, maars, prismatic basaltic columns, pyroclastic rings, craters, grottoes, cinder cones, ice caves, volcanic caps etc., from the Auverne in the Massif Central down to the Bas-Languedoc region near the Mediterranean. The book features classic images of cathedrals, abbeys and châteaux sitting precariously atop volcanic necks, nestling within descriptions of their geological origins and significance, as well as many of the beautiful natural volcanic features of central France.

Ask your Library for a copy!

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Very interesting again, i muust say that i would get quite concerned if Etna went as quiet as Vesuvius for 50 years or so, i'd expect a very big eruption.

As for volcanic activity in France, i can't see any major volcanic activity occuring over the next million years or so, though i suppose that some activity is possible.

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