Campi Flegrei

[bjdeming]

Well, there doesn't seem to be any news as of tonight. INGV declared an end to the swarm around 6-7 p.m. local time Friday, but as Dr. Di Vito said, it's a crisis and they are monitoring it closely.

This Naples media source (Italian) summed up the situation (and if nerdy stuff appeals to you, here is the paper they mention, which came out four days ago).

Via GT:

Magnitude 3.4 in the area of via dei Gerolomini and at about 500 meters deep. At dawn yesterday Pozzuoli was awakened by a very strong shock after a truce of about three months...The strongest shock was included in a seismic swarm that lasted many hours and characterized in almost all cases by very superficial shocks, in a fairly limited area between via Gerolomini, via Suolo San Gennaro and via Napoli.

<b>New element of concern</b>

The presence of superficial shocks could constitute an element of concern in the complex crisis situation of the Campi Flegrei...A situation of high risk due to the possibility, far from remote, of phreatic eruptions, that is, explosive eruptions without the involvement of magma, but no less dangerous in terms of public safety since they are not predictable, as they do not manifest themselves with precursors that scientists are able to interpret.

<b>The recent study by INGV/b>

In short, the pressure in the hydrothermal system has increased as also attested by a recent study by INGV...The director of the Vesuvius Observatory, Mauro Di Vito, explained to TgR Campania the other day: «Putting all the data together in this study, it was seen that the source of overpressure would be located around four kilometers, we are not talking about magma, however to have such a strong emission of gas from the subsoil there needs to be a magmatic degassing».

...

...an enormous pressure pushes towards the hydrothermal system fed by fluids that derive from the magma that (it is estimated) is located between 5 and 6 kilometers. The weakening of the crust reported by increasingly superficial earthquakes could «blow the cork» and cause a sudden phreatic explosion. This is one of the concerns expressed by the Major Risks Commission in recent months. In the document following the meetings of 27 and 28 October, published exclusively by the «Corriere del Mezzogiorno», the fears were made explicit in a chapter entitled «Possible occurrence of phreatic eruptions»...

...Giuseppe Mastrolorenzo is also convinced that «high temperature and pressure values in the hydrothermal system and low-depth stresses detected by superficial earthquakes can lead to a phreatic explosion that is not predictable». In short, in the Phlegraean caldera, magma is only one of the problems.

The emphasis in that new paper also is on possible powerful earthquakes. This is consistent with recent public statements from INGV that the densely populated region could experience up to estimated magnitude 5 temblors.

Add in a strong hydrothermal explosion, probably much stronger than the one Yellowstone's Biscuit Basin produced this year -- although just as unexpected -- and yes, it's a crisis even though INGV has noted in bulletins that the uplift has been slowing down since August.

 

[bjdeming]

Amazing news (Italian) on the social front: "No room for the Camorra" (a Mafia-like group). They are going ahead with seismic-related building improvements.

That shows just how deep this crisis has hit folks there.

 

[bjdeming]

Until this week, there have been a few seismic swarms but no major changes noted in the bulletins -- best of all, no hydrothermal explosion.

But now one of the long, moderately strong ones is on, and people reportedly (Italian, ads, possibly paywall) are nervous:

...Yesterday morning the Campi Flegrei were abruptly awakened by one of the longest, most energetic and concentrated seismic swarms of recent months. The strongest shock at 8:52 reached magnitude 3.1, three shocks exceeded magnitude 2 and the other dozens were between 1 and less than 1. Scholars expected this behavior, it has long been known that as the ground uplift progresses (about 2 centimeters per month) increasingly stronger and more numerous shocks occur. But yesterday fear began to spread again, especially in Pozzuoli where schools interrupted lessons and the emergency procedure was triggered for students and teachers. Francesca Bianco, director of the volcano department of the National Institute of Geophysics and Volcanology explains: "As long as the uplift continues, we must expect similar events. The phenomenon is not receding and we also continue to observe the increase in geochemical anomalies".

The strongest earthquake, that of magnitude 3.1, was located at a depth of almost 3 kilometers in the area of Solfatara and Pisciarelli, about 5 kilometers east of Pozzuoli. Bianco adds...«Magmatic fluid does not mean magma, but fluids that originate in an area where there is magma that degassed in depth».

...The volcanologist invites calm: «The earthquake is an internal shaking even for those who feel it, it reminds us that we are guests of a land with its own physiology, which must be respected». And on the management of the alarm: «The indications that we have been giving for some time are always the same: first, get correct information on the phenomenon. Second, avoid alarmist sites and fake news, and refer only to official sources such as the INGV. We talk about data, not opinions. Our monitoring network provides us with real-time information on the evolution of the dynamics of the Campi Flegrei».

The conclusion is clear: «We are experiencing a long bradyseismic crisis, which began in 2005, which with ups and downs shows us the dynamics of this volcano. Understanding it and dealing with it with awareness is the first step to living safely with this reality».

In the meantime, the Prefecture has mobilized with a meeting of the technical table coordinated by the prefect Michele Di Bari...

Alert level is still Yellow.

 

[bjdeming]

Per INGV, four hours ago: 203 quakes so far, strongest 3.9.

Some folks slept in the streets last night, reportedly (Italian, time dependent, but there are lots of stories right now).

Not at all a fine sciame.

Five hours ago:



X translation: "The earthquakes in Campi Flegrei, Italy, are rapidly increasing, with a M3.9 (USGS M3.0) occurring at 14:30 UTC on the 16th. Here is the epicenter distribution from INGV data starting from the 16th and the M-T diagram from January. The M3.9 was offshore, where occasionally larger earthquakes occur sporadically. The current activity center is near the Solfatara crater on land. There are also numerous earthquakes without determined magnitudes."



X translation: "Earthquakes at Campi Flegrei, just now two in succession with Md (duration magnitude) of 3.2 and 2.8 according to INGV. Monitoring records from the observation point CSOB near the Solfatara crater. INGV's website.https://t.co/2H2F89S56a"

 

[bjdeming]

Mayor of Pozzuoli, per Il Mattino's live coverage (Italian), browser translation: No catastrophe scenario from experts.

Per Cronaca Flegrea (Italian), browser translation:

...monitoring activity continues by the Rescue Coordination Centre, convened by the prefect of Naples, Michele di Bari, at the Civil Protection Operations Room in constant liaison with the prefect Fabio Ciciliano, head of the Civil Protection department, with the director of the Ingv, Mauro di Vito, the director of civil protection of the Campania Region, Italo Giulivo, the director of the regional school office, Ettore Acerra, with the police forces, the Port Authority, the Local Health Authorities, on 118, Enel, the Red Cross, as well as with the Municipalities of Naples, Pozzuoli, Bacoli and Monte di Procida, in particular after the 00.19 shock, of magnitude 3.9, in the Pisciarelli area...

Mayor of Naples, per Il Mattino/browser:

«This seismic swarm is part, as the Vesuvian Observatory pointed out, of the physiological dynamics of bradyseism in the Campi Flegrei. Obviously the tremors that have an epicenter closer to the city of Naples are felt more, as happened with the last one that had an epicenter in the Pisciarelli. We are monitoring all facilities very carefully, we have accelerometers, we are continuously carrying out inspections and
there are no reasons for alarm
with respect to the safety of structures.

For bradyseismic events there is the operational committee which is permanently convened in the Prefecture and all technicians are in the field.

I am personally following the situation
and we can tell citizens to be calm».

[\QUOTE]

I don't live in Naples, but he's got my vote!

 

[bjdeming]

Here's a graphic (there are some pics in the thread):



Er, well, the graphic is on the first tweet -- sorry. This swarm covers a wide area and is dense, too.

 

[bjdeming]

Another graphic:



It's worth noting that before the last eruption here, in the 1500s, there was dramatic ground elevation, with new land appearing along parts of the shore, etc.

Nothing like that is reported now. This layperson thinks that the biggest hazard is a large quake, and in earlier swarms Dr. Di Vito has estimated that might be in the M5 range.

A hydrothermal explosion is always a possibility, even without swarms, and such events occur without warning, as we saw recently at Biscuit Basin in Yellowstone.

 

[bjdeming]

From the blog:

This swarm is lasting much longer than typical ones.

Within the hour, INGV posted this update (Facebook translation):

Osservatorio Vesuviano Campi Flegrei update statement no. 11
Since 15:53 (UTC) on 15/02/2025 there is an earthquake in the Campi Flegrei area. At the time of issuance of this Communicato 450 earthquakes with magnitude Md mag 0.0 and a maximum magnitude Md = 3.9 ril 0.3. The map shows the locations of events with magnitude Md le 1.0. Further updates will follow depending on the evolution of the phenomenon. Find out more at https://buff.ly/4k1MrNE

Ten minutes later, they reported a M3.1 in the swarm. According to this report (Italian), that was the strongest of twenty quakes overnight.

Dr. Di Vito was quoted in the media yesterday as saying that no changes have been noted in volcano monitoring parameters.

 

[bjdeming]

This is just amazing. Latest official update per Il Mattino's current live coverage (Italian, browser translation):

Campi Flegrei update press release

Since (UTC) 3.53pm on 02/15/2025, an seismic swarm has been underway in the Campi Flegrei area.

At the time of issue of this Statement, 526 earthquakes with magnitude Md ≥ 0.0 and a maximum magnitude Md = 3.9 ± 0.3 were preliminarily detected.
The map shows the locations of events with magnitude Md ≥ 1.0.

Further updating will follow within 3/6 hours depending on the evolution of the phenomenon.

 

[bjdeming]

For background, here's the download site for the January 2025 (last) INGV update on Campi Flegrei (I use Google Translate's document function to translate these, going to desktop view when on mobile). There basically were no changes noted from previous months, and the volcano today is still at Yellow alert.

 

[bjdeming]

Another blog update -- the swarm continues and it is considered nonvolcanic:

INGV’s last update on Facebook was nine hours ago, and they said the next one would be out in three to six hours, if needed, so that non-news is good.

Their weekly bulletin is out, too, through the 16th, and it confirms what spokespeople have been telling the media: no significant changes have been noted in monitoring parameters.

Finally, Il Mattino has a self-translating article (this link probably will be in English) up that goes into detail about the crisis. Authorities and scientists say over and over to a very anxious public that this is not volcanic, they find no worrisome changes in the monitoring, and there is a plan and they are following it.

That last point especially, in this layperson’s opinion, is excellent reassurance against panic.

However, that said, Cronaca Flegrea reports (Italian) that the swarm continues, surpassing 600 quakes now and with at least two 3-pointers overnight.

 

[bjdeming]

Cronaca Flegrea reports (Italian) that the swarm has ended after 672 quakes. Greatest magnitude 3.9. Apparently most of Pozzuoli self-evacuated (good, if there had been an eruption!).

This was tweeted before that news -- just a look at the pattern:

 

[bjdeming]

Okay, I'm not sure why INGV did this all today, but they declared an end to the swarm that began on the 15th and had 672 quakes; a few hours later, now they say a new swarm is underway, and there are 22 quakes thus far. Il Mattino reports (Italian) two 3-pointers.

It's all in the Solfatara/Pisciatelli area -- both swarms.

Something has changed from the usual Campi Flegrei seismic pattern; in the reported absence of eruption precursors, this layperson wonders if the bradyseism, which has been going down since last year, will now start to go up.

Such changes have occurred in the past, though, and without such swarming AFAIK (not far).

Huh...

 

[bjdeming]

Looking at this image again, it could be something altered in the hydrothermal system, too. (Of course, that and the bradyseism are interconnected.)

<Layperson speculation>It's way too early to say anything definite about it, but teleseisms do affect volcanic systems sometimes, particularly when those systems are "primed" in some way. Campi Flegrei doesn't sound as though it's primed for a magmatic event, but the hydrothermal system? Perhaps -- they've been talking about chances for a steam explosion recently.

The teleseisms would be from that long-lasting, strong Amorgos-Anhidros swarm over in the Aegean. That's weird, and AFAIK it's not ludicrously impossible that it could trigger weirdness in any primed system, especially in the same Mediterranean basin.

As long as this layerson is babbling, why not babble this: could teleseisms cause atypical gas bubbles in Campi Flegrei's hydrothermal system that are "knocking the pipes"? </layperson speculation>

 

[bjdeming]

More on eruption likelihood in the short term (VERY low) from La Repubblica (Italian).

 

[bjdeming]

About seven hours ago INGV noted this second swarm is over. The strongest shock was actually a 2-pointer. Not much other news -- everyone is probably still recovering from the excitement.

 

[bjdeming]

There has been a third swarm, starting on the 21st, and INGV announced its end about six hours ago: 27 quakes, strongest M2.1.

I don't know how they distinguish between swarms.

Also interesting is this article (Italian, ads) on what it's like to be a commercial fisherman through all this. Among other things, he notes that the fish sometimes come up cooked!

 

[bjdeming]

I missed the end of the last swarm. This is new, from Facebook, posted within the hour:

Update statement #CampiFlegrei no. 2:28 am (local time) Since 1:51 (local time) on 01/03/2025 there is an earthquake in the Campi Flegrei area. At the time of emission of this Communicato, 20 earthquakes with magnitude Md = 0.0 and a maximum magnitude Md = 2.1 ≥ 0.3. The map shows the locations of events with magnitude Md 1.0 1.0. Within 3/6 hours a further update will follow depending on the evolution of the phenomenon. Further information on the website of the INGV Observatorio Vesuviano, data bank GOSSIP https://buff.ly/r7rFxWa

 

[bjdeming]

INGV reported an end to the swarm after that notice. Cronaca Flegrea reports (Italian) today that a gym complex in Pozzuoli had to be closed because of high CO2 levels; no high CO2 reported in Bacoli, in another story, while in a third story, someone from INGV discusses volcanic degassing.

My first impression was positive, since CO2 comes out at depth. Sulfur dioxide and H2S are signs that magma is near the surface. But then -- why now?

Campi Flegrei already has been degassing big time for many decades.

Perhaps the recent quake swarms, possibly helped along by the hypothetical "knocking in the pipes" I mentioned earlier, indicate the opening of another crack, this time outside the present degassing network through Solfatara and Pisciatelli (which does carry sulfur compounds)?

 

[bjdeming]

No major changes -- INGV has a page (Italian) on all recent quakes M4 or greater plus some articles below that on the recent swarms, including February's.