Vulcano – The island that lent its name to an entire branch of geology

The island of Vulcano (source: wikipedia)

The volcano helpfully called ‘Vulcano’, one of the islands, north of Sicilyhas give its name to all volcanoes in the world. Vulcano last eruption was in 1888-1890. During the long repose period, a settlement has grown from a few houses to villas and hotels. Frazzetta et al. wrote in 1984 (quoted by Boris Behncke)

“A volcanic hazard exists where there is the potential for loss of life or property as the direct result of volcanic activity. The major effects of all activity at Fossa are confined to within 2 km of the vent. The village of Porto with a population of about 250 inhabitants lies within this zone to the north of the main cone. During the summer the population of this town swells to more than 10,000. It is quite dangerous for a village to be located so close to an active volcano.”

The settled community has grown from 250 to 450 since 1984, and in August there may now be 12,000 tourists each day (Behncke, private communication). The location of this community so close to the crater has made Vulcano into the second most dangerous volcano in Italy, after only Vesuvius. And now the alert level has been raised to yellow. Luckily this is after the summer and the height of the tourist season. But we are concerned.

The following post is one from the archives. It was written by Henrik in 2013, and is well worth resurrecting. At the end, we also reproduce a description of past eruptions from the current crater, Fossa, based on an article by Boris Behncke and reproduced by permission.

Over to Henrik:

Fig 1. “The Thunderbolts of Zeus”. One of the amazing photographs taken by the incomparable Marco Fulle, often reproduced on the Internet without giving credit to this wonderful photographer.

Hephaistos, the lame son of Zeus and Hera, the King and Queen of the Hellenistic Pantheon, was the god of blacksmiths, artisans, craftsmen, metals, metallurgy, fire and volcanoes. He was also the weaponsmith of the Gods and crafted, amongst other things, the thunderbolts of Zeus.

Of course the Romans, the greatest copyright infringers ever produced by mankind incorporated the Greek Pantheon as their own religion and mythology. Here, Hephaistos was known as Vulcanus. The roman scholar Marcus Terentius Varro (116 – 27 BC) cites the Annales Maximus, which go back to at least 400 BC, as the source of the first mention of Vulcanus. He mentions that king Titus Tatius (d.748 BC) dedicated a series of altars to deities among which Vulcan is mentioned.

Perhaps more suggestive is the fact that a new eruptive centre formed in the strait between Vulcano and Lipari with the first recorded eruption occurring in 183 or 123 BC. The eruptions went on for more than a century, thus were contemporary with Varro, and formed a new island Vulcanello. This was volcanic creation of new land where only sea had been before and must have been considered by the ancient world as very significant proof of divine existence and omnipotence. In addition to its theological usefulness, Vulcano provided the Romans with wood, alum and sulphur, activities continued as the main produce of the island until the last, or rather, most recent series of eruptions of 1888-90 ruined the mining works. Today, Vulcano is home to some 500 year-round inhabitants while in the summer, the population grows to about 10,000. But not to worry, renewed activity will almost certainly be preceded by irrefutable signs of unrest well in advance of any potentially devastating event.

Fig 2. Geology of Vulcano (Gioncada, Mazzuoli, Bisson & Pareschi 2003)

The visual appearance of Vulcano is very suggestive with the most ancient centre of activity, the collapsed stratovolcano “South Vulcano” (ca. 120-98 kA) and Piano Caldera (ca. 98-97 kA) to the south, the Lentia Complex (15.5 kA) with the Lentia or Fossa Caldera (16 -13 kA) in which the new La Fossa cone (~6 to 5 kA) grew. To the NE of the Fossa cone an extrusion is obvious but no date has been given for it (14 kA Punta Roja lava flow?). Finally, to the north is the already mentioned Vulcanello complex (2.1 kA).

Activity at Vulcano began a mere 150,000 years ago and is divided into four major stages. The first, South Vulcano center, began at about 120 kA by building a trachybasaltic to trachyandesitic stratovolcano where pyroclastic fall and flow deposits constitute only a minor portion. The activity at South Vulcano came to an end with the collapse of the stratovolcano around 97 kA into the 2.5 km diameter Caldera del Piano. Interestingly, it seems that the caldera was formed, not by an eruption that led to a collapse but the collapse of the stratovolcano “for reasons unknown or unspecified”. Post-caldera activity continued for some 45,000 years which resulted in most of the caldera being filled by lava flows. Then there seems to have been a period of inactivity covering the next 30,000 years.

Fig 3. Looking north. An aerial photograph of the infilled Lentia Caldera with the Gran Cratere of the La Fossa Cone and island of Vulcanello

About 15½ thousand years ago, activity renewed at Quadrara and Spiaggia Lunga as well as the formation of the large rhyolitic to trachytic lava dome and flow complex of Lentia, the “Lentia Lava Dome Complex”, in the northwest. From somewhere in the strait between Vulcano and Lipari (proto-Vulcanello?) violent ash-flow forming eruptions occurred and deposited brown tuffs over a large area of the old Caldera del Piano to the south.

About 15-14 ka ago, another caldera collapse affected the island, this time in its northern part, forming the Lentia caldera. Again, there seems to have been no explosive eruption associated with the caldera collapse, which may have been “tectonically triggered”. Activity continued within the new caldera with at least five cycles of pyroclastic and lava flows, the most significant being the Punta Roja lava flow that crops out at the E base of the La Fossa cone. Eruptions also occurred from N-S trending fissures in the NW part of the older Piano caldera where the Alighieri formation and the edifice of Monte Saraceno were formed.

Fig 4. Inside the Gran Cratere of La Fossa (volcano.oregonstate.edu)

About  11,000 years ago, activity began to concentrate in the centre of the Lentia Caldera and at least four eruptive cycles formed the massive-looking albeit only 391 m high La Fossa cone. Over the past 2½ thousand years, there have been at least 15 confirmed eruptions with a further ten possible from La Fossa with the last terminating on March 22nd 1890.

Fig 5. A post card of Vulcanello from Lipari

Although activity at La Fossa continues and cannot be said to be over, the last major eruptive period recognised is the already mentioned one that began in the second century BC and led to the formation of the Vulcanello Island and complex. Eruptive activity continued with at least two further eruptions after the initial, island forming series ended in ~10 AD. The final eruption, that of 1550, connected Vulcanello with Vulcano. The activity produced three overlapping tephra and scoria cones with craters shifting from E to W, and a gently sloping lava platform mainly on the N, W and S sides of the cone cluster. The Vulcanello products are generally more mafic than most other Vulcano eruptives, being of leucite-tephritic composition, only the most recent lava flow, Punta del Roveto of 1550 being trachytic.

HENRIK

Fossa, 2018. Source: Volcanodiscovery

Henrik ended his post with: For further reading, I highly recommend Dr Boris Behncke’s former site, thankfully saved for posterity by the Michigan Technological University

This site does not appear to exist any more. We reproduce here part of the content, describing the eruptive cycles of the Fossa cone over the past 6000 years. The text is slightly edited from the original. The images as shown here are available at https://slidetodoc.com/3-volcanoes-killers-and-creators-dr-daniel-barker/

The evolution of the Fossa cone, the most recently active volcanic center on Vulcano island, has been described in detail by Frazzetta et al. (1983) and briefly reviewed by Frazzetta et al. (1984) and Frazzetta & La Volpe (1991). The following is a summary from those sources.

The Fossa eruptive center developed only during the past 6000 years, after the presumably tectonically triggered formation of the Fossa caldera, about 14-16 ka ago. Its birth followed post-caldera effusive activity of which the 14 ka Punta Roja lava flow gives testimony. Activity of the Fossa cone has been divided into several cycles by Frazzetta et al. (1983, 1984) and Frazzetta & La Volpe (1991). The cycles have generally shown a characteristic succession of eruptive styles and each had an individual eruptive vent. Some cycles began with powerful vent-clearing explosions leading to deposition of “phreatic breccias” near the eruptive vents. The hydromagmatic initial stages of other cycles produced wet and/or dry surge deposits. Later products of each cycle show a decreasing influence of external water, the final products being fully magmatic (pumice-fall deposits or lava flows).

There is a complete lack of erosional surfaces and paleosoils between the products representing a cycle. It is assumed that activity during each cycle was more or less continuous. This contrasts with distinct erosional unconformities between the products of various cycles, evidence of longer repose periods separating different eruptive cycles.

Punte Nere cycle

The initial activity of this first recognized Fossa eruptive cycle was hydromagmatic and produced a more than 60 m thick sheet of dry surge deposits overlying the Punta Roia lava flows (14±6 ka). The basal strata of this sheet are composed of coarse and fine clasts and are overlain by sandwave and massive beds. Fragments of a trachytic lava flow that may have been ruptured by the eruptions and a thick block-fall deposit are present in the middle part of the sequence. A fall deposit composed of normally bedded and occasional reversely bedded layers with interbedded surge beds make up the uppermost pyroclastic unit of the cycle. It was followed by the emplacement of the trachytic Punte Nere lava flow that forms a delta-like feature on the N base of the Fossa cone. This flow was dated at 5400±1300 years.

Frazzetta & La Volpe (1991) estimate the volume of tephra produced during the Punta Nere cycle at 195 x 106 m3 and that of lava at about 3 x 106 m3. The activity left a cone about 250 m high. The NE crater rim is still well discernible in the eastern part of the Fossa cone.

At least three undefined eruptive cycles occurred after the Punta Nere cycle and left wet and dry surge deposits as well as the Campo Sportivo lava flow (see the map of lava flows), on the NW base of the Fossa cone. That flow has a radiometric age of 4600±1700 years and thus falls into the same time window as the Punta Nere flow; stratigraphically, though, it lies in a higher position. The volume of the Campo Sportivo lava flow is 2.6 x 106 m3 while that of the tephra presumably associated with it is 25 x 106 m3. The volume of tephra from the other undefined cycles is about 10 x 106 m3.

Palizzi cycle

Following a repose period of unknown duration, hydromagmatic activity led to the emplacement of wet surge deposits followed by dry surge beds. Accretionary lapilli in these initial deposits give testimony of a high water component during the opening stage of the cycle. Later activity produced a stratified, normally graded pumice horizon which shows evidence of a brief erosional interval at its top. When activity resumed, it was again hydromagmatic and deposited another set of basal wet and overlying dry surge horizons.

Like during the preceding cycle, the late stage activity was effusive, producing about 0.6 x 10^6 m^3 of trachytic lava that forms a narrow tongue on the southern flank of the Fossa cone (Palizzi lava flow, see the map of lava flows). The volume of all tephra emitted during the Palizzi cycle is given as 5 x 106 m3. The age of the Palizzi lava flow is 1600±1000 years. This is well within the historic period but no correlation of the deposits with recorded historic eruptions of Vulcano is possible.

Comenda cycle

This cycle began with powerful explosive activity of which a basal breccia gives testimony. The breccia is composed of yellow hydrothermally altered clasts and is overlain by a pyroclastic flow unit with numerous fumarolic degassing pipes. The activity then shifted to hydromagmatic and produced wet and then dry surge deposits with abundant Pele’s hair (!) before it became again magmatic with the extrusion of the Comenda obsidian lava flow that is still partially visible on the SW flank of Fossa cone (see the map of lava flows). Its volume is 2.6 x 106 m3, slightly more than one tenth of the tephra volume (25 x 106 m3).

Frazzetta et al. (1983) assumed that the upper and larger of the two Forgia Vecchia (“Old Forge”) craters was formed during the Comenda eruptive cycle. These craters are well distinguishable on the two photos below of the 1888-1890 eruption but have been subjected to intense erosion since then and are densely vegetated.

The initial activity (breccia and pyroclastic flow) probably occurred before the mid 6th century AD since these deposits are overlain by the white ash from the most recent explosive eruption of Monte Pilato, Lipari that is thought to have occurred around AD 550. The Pilato ash is overlain by the wet and dry surge deposits. Historic documents indicate that the emplacement of the Comenda lava flow may correspond to an eruption recorded for the year AD 785.

Pietre Cotte cycle

Initial activity was hydromagmatic, producing wet surge and soon after, dry surge deposits. A pyroclastic fall sequence (described as “pumice” by Frazzetta and La Volpe 1991) rests on top of these early products. The exact timing of the eruption’s beginning is not known but it is probable that one of its more peculiar events, the formation of the lateral Forgia Vecchia II crater (on the NW rim of Forgia Vecchia I crater), occurred in 1727. Twelve years later, lava seems to have filled the main Fossa crater and spilled over its low N rim, forming the obsidian lava tongue of Pietre Cotte (“Cooked Stones”) that is still conspicuous on the steep northern slope of the Fossa cone (see the map of lava flows). Its volume is 2.4 x 106 m3.

Unlike other cycles, the Pietre Cotte cycle apparently did not end with the lava outflow. Following the effusive activity, eruptions resumed in 1771 and continued intermittently until 1890. All activity before the latest major eruptive episode, in 1888-1890, is not well documented whereas very detailed scientific descriptions of the most recent activity are available (see below).

1888-1890 eruption

Photo of Vulcano in eruption, 14 February 1889. This view is of an explosion that ejects large bombs or blocks above a steam and ash plume. This photo was originally published in Mercalli & Silvestri (1891) and shows evidence of slight editing.

Vulcano last erupted in 1888-1890. Although it had erupted frequently in historic times, this eruption was the only one that was observed by scientists and was described in detail (Mercalli & Silvestri 1891). The activity observed by them was used for the introduction of a new scientific term, the so-called “Vulcanian” style of volcanic activity, now applied for powerful magmatic activity somewhere transitional between Strombolian and sub-Plinian.

The eruption was particular for the ejection of countless large breadcrust bombs. Meter-sized bombs fell in the area now occupied by the village of Vulcano Porto, on the crater rim they are much larger.

This is the largest of the famous breadcrust bombs ejected during the 1888-1890 eruption from Fosa Grande (the crater visible in the background). Giada Giuntoli is the person who gives scale. This bomb didn’t make it far away from the crater, but smaller ones fell abundantly in the area now occupied by the village of Vulcano Porto. 18 April 1995.

The buildings of the sulfur mining company located at Porto Levante were heavily damaged by falling tephra already during the first days of the eruption (starting on 3 August 1888), their residents could escape without fatalities or injuries. Later eruptions caused occasional ash and rare lapilli falls at Lipari. No major damage was done there, but the area now occupied by the village of Vulcano Porto was subjected to heavy bomb and lapilli showers.

The eruption ended on 22 March 1890, after gradually declining for several days. There were repeated unconfirmed reports about eruptive unrest at or near Vulcano, but no significant eruptive activity took place after 22 March 1890.

With the 1888-1890 eruption, the Pietre Cotte cycle seems to have come to a close. The volume of tephra produced during the entire cycle is given by Frazzetta & La Volpe as 25 x 106 m3 of which the 1888-1890 products do not make up more than one fourth.

531 thoughts on “Vulcano – The island that lent its name to an entire branch of geology

  1. Last earthquakes on la palma, after 4.3
    3.2 mbLg N FUENCALIENTE DE LA PALMA.ILP 2021/10/07 15:52:54 11+info
    3.9 mbLg NE FUENCALIENTE DE LA PALMA.IL 2021/10/07 15:49:15 12 +info
    2.7 mbLg SW VILLA DE MAZO.ILP 2021/10/07 15:23:14 10 +info
    3.8 mbLg SW VILLA DE MAZO.ILP 2021/10/07 14:26:04 III 37 +info
    3.2 mbLg N FUENCALIENTE DE LA PALMA.ILP 2021/10/07 13:24:32 14 +info
    2.8 mbLg SW VILLA DE MAZO.ILP 2021/10/07 13:18:26 11 +info
    2.7 mbLg SW VILLA DE MAZO.ILP 2021/10/07 13:14:20 11 +info
    2.9 mbLg NE FUENCALIENTE DE LA PALMA.IL 2021/10/07 13:04:31 33 +info
    3.1 mbLg NE VILLA DE MAZO.ILP 2021/10/07 12:51:17 34 +info

  2. Color (not viscousity 🙂 ) looking like barely 800 °C right now, in the https://youtu.be/INvrtMg5tSQ live stream 😮 .
    Maybe laymen should stop trying to estimate the lava temperature from the lava color over the live stream, and accept the 1150 °C, which was suggested earlier for the effusive vent =D.

    (I will protect VC from more temperature spam of mine in the future^^)

    On-topic: Yes, the vent, which previously has been effusive, is making some strange appearance…

  3. La Palma:
    As already briefly mentioned here, a new partial flow has formed. This branched off south of the main stream yesterday. The flow has already destroyed some banana plantations (a total of 9 hectares), some water tanks and several buildings. Today it was moving down the cliff above the coast. There the flow expanded on the “Las Hoyas” peninsula, which was created in 1949 by the “San Juan” eruption. In the meantime the flow should have reached the coast at “El Charcon” beach.
    I liked to visit this beach, which is framed by craggy rocks, during my stays in La Palma. There is a great sea swell there and I loved how the waves crashed on the rocks in this quiet place. It would be a real shame if this stain will be destroyed now.
    More in Spanish in El Time:
    https://www.eltime.es/isla-bonita/35800-el-nuevo-dedo-de-lava-se-lleva-casi-10-hectareas-mas-de-plataneras-y-algunas-casas.html

    A photo of a part of the beach at the Playa El Charcon I took in 2006:

  4. Whilst reading about eruptions such as this one it was stated that the column is black whilst older matter and eroded sides are being ejected. Later the column turns white, which I think has now happened.
    Sadly I cannot remember what this transition means.

    • Black column = Column containing fresh ash. Mostly generated by explosive emissions like lava fountains.
      Wihite column = No ash only water vapor. Mostly generated by effusive activity, spattering vents, lava flows, fumaroles.
      Bluish column = A lot of sulfur dioxide. Mostly generated by lava flows, strombolian acivity, fumaroles.
      Brownish column = Cloud containing old ash. Mostly generated by collapse, impact of bombs, sliding of rocks.
      Reddish column = Old, (chemically) eroded, pulverized rock. Mostly generated by awekening of old vents, throat cleaning explosions.

      • Forgot:

        Gray cloud: Steam mixed with some fresh ash. Often appears as a cauliflower-shaped cloud in severe explosions, Plinian eruptions etc.

  5. There may be a new vents trying to open where there was rifting early in the eruption. I am watching the AFAR feed so using that time stamp. Down to the left of the frame around 18:56 you will see what appears to be a light that is flickering. This is about 2 fingers up from the bottom and two fingers ( held up to the screen) from the left edge. At 18:56:26 you will see hot targets being expelled in the general area a little below the big target and then just above it. at 18:56:42 you see some more up and too the right, then more.

    Mac

  6. Do we have a volcanologist duel in sight? These two articles about the La Palma eruption give exactly the opposite conclusion. 300 000 years old magma rejuvenated within a very large chamber vs. fresh new magma straight from the plume, and no significant rest in a chamber.

    https://elpais.com/ciencia/2021-10-05/asi-es-la-lava-del-volcan-de-la-palma-por-dentro.html?fbclid=IwAR0oSBKBmIB_RWZe1iGH921m0yO9N3uZCT_m8v9BxSW_4ldzqs6ycvmOaEM

    https://www.lavanguardia.com/vida/20211006/7773430/tres-volcanes-palma-comparten-magma.amp.html?utm_term=botones_sociales&fbclid=IwAR0SbZ5SS_bhbDRHtz0Go0tnp1UVnAD1z7rYbwRcUifRLFDT5EK7TTZEId0

    I would love to watch the fight and see the petrology diagrams flying, but I suspect that one of the two will just be forgotten.

    As I dare saying despite my limited knowledge, I suspect that the Canarias plumbing is very much misunderstood, and that there is some overconfidence in some books on the subject. But I’d like very much to be proven wrong by new data as well.

    • The only petrology statement I have heard about is the lava being tephrite.
      Wonder if there are any more data points as of today? Do we know if it is changing? What about the basanite?

      • Compared to Iceland, the information is night and day. Not to mention the usual reassuring speeches from the local politicians as soon as the eruption slows down for a bit -_-

        I have a huge respect for the guys who managed the evacuation and secure the area, but transparency isn’t their forte.

        • That’s a bit harsh when they are dealing with an evolving disaster. Safety still has to be their no. 1 priority, aid their no 2 priority … Sharing petrology data internationally right now is lower on the list. However, you can find a lot of data, even if IGNs is not exactly the same as IMO’s.

        • It’s not harsh. You are showing enough respect for rescue teams. Politicians are habitual lars, and nobody understands why.

      • Basantite is tephrite that has a lot of olivine in it, both fit under the broad definition of ‘alkali basalt’. I think it is more physical characteristics that differ, tephrite might be more likely to erupt cooler and the olivine settled out, but that is not a rule, the lava erupting now is as fluid as it is in Hawaii (watch the raging lava rapid after that flank collapse) and still tephrite composition.

        Canary islands seem to be different entirely from Iceland or Hawaii. Both of those have continuous supply, the Canary volcanoes seem to be very episodic but when actually in an episode potentially can outperform both Hawaii and Iceland. Lanzarote is an example, maybe a bit of an extreme example though, it was going at 1 km3 a year supply rate, maybe even a bit more, over a period of 6 years. These episodes seem to be far apart though, so long term magma flux is way lower than Hawaii.

        Still, it is not impossible this is one of those massive eruptive events, involving years of eruptions and many km3 of lava. Before this started I would have never thought this but seeing how big the eruption is and that there is no sign at all of anything stopping any time soon it is not looking so impossible anymore. It has done in 3 weeks what it took Fagradalshraun at least as many months to do.

        • Yep. I am absolutely puzzled about Tajogaite!
          Would’ve never ever expected such an eruption!

          Meanwhile, I think FAF is pretty much gone.
          While the tremor chart is looking somewhat noisy, one has to take into account that the Icelandic Low is in the close vincinity.
          Hence I suspect it being wind noise rather than unrest.

  7. Suspect the quakes are just the system reacting to the shallow magma being drained out, sort of a vacuum effect where deeper magma gets sucked up to fill the space and balance the pressure. The deeper reservoir will likely be between Teneguia caldera and the Vieja ridge, whereas there will be shallower storage systems along the ridge and particularly towards the south end where the initial swarm started.

  8. Last earthquakes after 15 hours, some 3.5
    3.5 mbLg N FUENCALIENTE DE LA PALMA.ILP 2021/10/07 18:55:36 12 +info
    3.1 mbLg N FUENCALIENTE DE LA PALMA.ILP 2021/10/07 18:42:40 10 +info
    2.7 mbLg NE FUENCALIENTE DE LA PALMA.IL 2021/10/07 18:24:31 12 +info
    2.5 mbLg N FUENCALIENTE DE LA PALMA.ILP 2021/10/07 17:21:50 11 +info
    3.5 mbLg SW VILLA DE MAZO.ILP 2021/10/07 17:14:38 14 +info
    3.4 mbLg NE FUENCALIENTE DE LA PALMA.IL 2021/10/07 16:52:59 10 +info
    2.6 mbLg N FUENCALIENTE DE LA PALMA.ILP 2021/10/07 16:47:20 13 +info
    2.7 mbLg NE FUENCALIENTE DE LA PALMA.IL 2021/10/07 16:19:28 14 +info
    2.9 mbLg N FUENCALIENTE DE LA PALMA.ILP 2021/10/07 16:13:42 13 +info

    The vulcano summit has “reapear”.

    • Just witnessed that while watching, looks a bit more fluid to me now!
      Interesting part was 19:55 to 20:00 UTC.

  9. The Vulcano website of Boris Behncke still exists:
    https://www.italysvolcanoes.com/VULCANO.html

    It is interesting to read there that there was a period of unrest in 1985. It was in parts similar to the current situation. Increased seismic activity, changed gas composition and higher gas temperature. At that time there was no eruptive activity. Will it go off so lightly this time too?

    • I haven’t seen any more updates on it over the last few days to know whether it’s calmed down since,volcano discovery dosn’t really show many earthquakes around it, not sure about inflation/tremors etc.

  10. La palma lava pool vent making pulses and explosions. I think that can be convert on a new cone with expand the volcano to the north.

    Earthquakes maintain 10-12 km deep, but some has sense.
    3.1 mbLg NE FUENCALIENTE DE LA PALMA.IL 2021/10/07 22:52:49 13 +info
    3.5 mbLg NE FUENCALIENTE DE LA PALMA.IL 2021/10/07 22:47:16 III-IV 14 +info <=
    3.0 mbLg NE FUENCALIENTE DE LA PALMA.IL 2021/10/07 22:30:12 14 +info
    3.0 mbLg N FUENCALIENTE DE LA PALMA.ILP 2021/10/07 22:18:22 14 +info
    2.6 mbLg NE FUENCALIENTE DE LA PALMA.IL 2021/10/07 22:09:00 14 +info
    2.2 mbLg N FUENCALIENTE DE LA PALMA.ILP 2021/10/07 22:07:17 10 +info
    3.1 mbLg SW VILLA DE MAZO.ILP 2021/10/07 21:55:32 11 +info
    2.5 mbLg NE FUENCALIENTE DE LA PALMA.IL 2021/10/07 21:19:23 13 +info
    2.7 mbLg NE FUENCALIENTE DE LA PALMA.IL 2021/10/07 21:07:50 14 +info
    2.5 mbLg N FUENCALIENTE DE LA PALMA.ILP 2021/10/07 20:37:37 10 +info
    2.5 mbLg SW VILLA DE MAZO.ILP 2021/10/07 20:20:49 10 +info
    3.4 mbLg NE FUENCALIENTE DE LA PALMA.IL 2021/10/07 20:19:24 13 +info
    2.8 mbLg N FUENCALIENTE DE LA PALMA.ILP 2021/10/07 20:06:03 12 +info
    2.9 mbLg NE FUENCALIENTE DE LA PALMA.IL 2021/10/07 20:00:22 14 +info
    2.8 mbLg NE FUENCALIENTE DE LA PALMA.IL 2021/10/07 19:35:12 11 +info
    2.4 mbLg NE FUENCALIENTE DE LA PALMA.IL 2021/10/07 19:20:20 10 +info
    2.4 mbLg SW VILLA DE MAZO.ILP 2021/10/07 19:14:28

    The sound has heavy…..

  11. 2:25:24 am CET very bright and big pyroclastic flow cut loose down the mountain side, this will get INVOLCAN into action

      • steady jet engine sound for minutes. where is the FLIR camera when you need it?

    • That was wild. Covered at least 25% of the cone. I didn’t see an obvious crater wall collapse, it seemed like there was a huge increase in the magma flux for a couple of minutes.

      • damon, it is 2:54 am CET and that almost constant venting noise for 1/2 hours with loud volume is not good. Lots of pyroclastics are going somewhere. I wish someone had a FLIR camera to see through the clouds and smoke.

    • I really wish the broadcasters would take a tip from Iceland and timestamp all their feeds, makes life so much easier for those catching up in the morning !

  12. 07:29:30 am CET large eruptions of lava now high into the sky, lots of lava per burst

  13. That collapse of the cone perfectly shows how closely related lava flows and pyroclastic flows really are. The actual collapse behaves more like a pyroclastic flow, moving very fast down the slope and with a lot of ash blowing up above it, and really if it happened in the day that is exactly what it would be described as. When it slows down it starts flowing like a normal lava flow though, and the area was also covered by lava from the vent directly too, all hot fluid lava that is erupted effusively.

    I guess really there is not much of a difference between a lava dome and a spatter cone that is still being created and partly molten, except maybe for gas content.

    • Do you have estimations about its velocity?
      I’d expect a true pyroclastic flow to look more cloudy and move even faster.
      And don’t we need a high column to collapse for that or a powerful pelean lateral blast?

      Is there videos or photographs of a “true” (or large) pyroclastic flow, which is incandescent too?

      • Pyroclastic flows are always incandescent, it is basically a landslide of lava blocks, just in more viscous lava a lot of ash is formed too which stops glowing quick and blocks it. The flow itself would look pretty much exactly like this.

        PF from lava domes also contain more gas, this is a collapsing spatter cone just a really huge one, so degassed lava, it is not 100% the same but very similar.

        Moves around 40-50 meters a second, so around 160 km/hr. The bit that is more scary to me is that the lava held behind the collapsing cone actually moves faster than the collapse itself, being diverted into the air over a bolder probably around 50 meters high at one point… Not confident on my measuring but there is some REALLY fast lava in that video.

  14. Here in Europe we are suffering from a severe energy crisis with exploding natural gas and electricity prices. Many households can’t pay there energy bills now due to this price explosion. This means austerity when its about using natural gas for heating and cooking.

    I think that Europe should switch to geothermal energy. Can the Upper and Lower Rhine Graben and the VulkanEifel provide enough heat to be used as a source for heating and generating electricity in Germany and the Benelux?

    • Western Europe haves a thin continetal litosphere.. sometimes only around 100 kilometers or even much thinner than that, so yes something of Geothermal coud perhaps be tryed.
      Litosphere is quite thin in France as example and coud be tryed there.

      But in Sweden, Finland and Western Russia geothermal is Impossible.. as they are the worlds thickest craton.
      I think in Moscow and Finland the litosphere can be as thick as 330 km, Thats so thick that not even poweful mantle plumes can melt through.

      Still Siberian Traps acually managed to pierce a ”near cratonic enviroment” But it did not broke through a real craton I think

      • Geotheral can be quite dirty, BTW. Can pollute ground water, and also cause shallow earthquakes …

    • I think there is a problem with the amount of energy required to power Germany and the Benelux.
      There are serious experimental setups to at least use the geothermal heat to heat up buildings.

      But with these experiments come disruptions of the heat balance underground: this results in earthquakes.
      Just like winning natural gas and oil does generate earthquakes.

      There is still room for improved energy usage and smarter handling of fossil fuels: start with prohibiting the use of fossil fuels for stationary applications.

      The main reason for the energy crisis is not due shortage of fuel but due speculation and how the energy market is organised: electricity cost is pushed up due the high cost of natural gas. But this also brings more income for those that make energy from other sources (nuclear and renewable sources)
      A simple statement of Putin was sufficient to pull the plug from the speculation.

      • No, its due to shortage, much of which is due to massive purchases by china as it tries to move from coal.
        Its very simple, if you cut production by preventing development of fields/infrastructure/storage etc then you will end up finding the demand outstrips supply. Demand exceeds supply and prices rise. Simple economics.
        This is because nobody wants to accept the fossil fuel consumption is ENTIRELY generated by people’s demands and only by radically reducing demand will fossil fuel usage fall.
        Eg: no foreign holidays, no card with engines >750cc, lock on max indoor temps to 18C, no beans flows in from peru etc etc.
        Not going to happen.

        • No foreign holidays, no sun. When I am away between September and April I use next to no heat and energy. If we all stay home in the cooler countries, energy consumption will rise, not fall, and warmer countries will suffer from the loss of tourists.
          One-fold proposal, short-sighted. What about finally putting pressure on China?

    • There are places where that can be a significant energy source. Iceland does it, of course. Where it is possible, it is rather cheap. Away from volcanic areas, the heat flux is much lower, on average 65 milliWatt per square meter. (That is also true in the cratons, by the way, as it is mostly generated by radioactivity in the crust.) This is too small to be useful (solar and wind produce much more) but you can extract much more ground heat, just that it is no longer strictly speaking ‘renewable’. The most efficient way of using it is I think a ground heat pump. You still need to generate electricity to use them but it reduces electricity usage by half.

      • On IO geothermal heating will not be a problem.. if you coud runn it without water.
        IO is very dry and water woud need to be imported in the plant systems.

        Albert since IO is madely volcanic.. is the heat flow of IO s avarge similar to Iceland?

        Whats IO s avarge in milliWatt per square?

        Sulfur and mineral mine colonies are common on IO in Sci Fi games and litterature

    • The UK have a cunning plan that from 2025 all new housing must be low-carbon heating, solar plus heat pumps. I cannot actually see this happening, because the ground source (water/antifreeze in long pipes) will have to be drilled in the ground (modern gardens are very small), and I am very doubtful we have the number of drill rigs or geologists needed.

      • Almost all heat pumps do not work. If they did they would have been in use for decades, the technology goes back 100 years.
        They do work for heating outdoor swimming pools in summer (cover surface every evening though).

        • Best used for low temperature heating, and well insulated houses. There must be some of those even in the UK?

        • Sorry, but that is simply nonsense. They have indeed been successfully in use for decades, and in the last decade or so have gotten even better. I personally know of many installations, including in the US and Europe, some with substantially colder winters than those in the UK.

          They absolutely work (both ground pumps and air pumps), as long as the oil and gas prices were low they are just not the cheapest option (but for typical electrcity prices it is not even a huge difference). Plus, as Albert writes, in houses without low-temp heating cycles (floor heating, or air heating, for example) they don’t reach maximum efficiency.

          There are things to discuss there about electricity etc., but to just say they don’t work is just wrong.

    • Lava is a very very good insulator
      It takes a long time to cool off
      Basalt is excellent at stooring heat

      Fagradalshraun is very very very thick too basicaly a lava filled valley
      Its going to take 100 s of years to cool off. It haves so low heat conductivity

    • Snow will settle on Fagradalshraun quickly.. But just underneath it will be very hot Indeed. Lava is a good insulator

      Its possible that older active compund Pahoehoe flow fields in Iceland can have snow on them .. on their thicker parts. And active lava tubes with one meter thick crusts haves snow on them

      Rock is insulating

      • Dave McGarvie
        @subglacial

        will keep looking he is saying 120m of lava is approx 30y of cooling. it will be interesting to watch.

    • Interesting lava has erupted in that bit of the caldera twice, not exactly the same spot but the fissures line up and are clearly not entirely unrelated. Obviously other vents opened under the lake somewhere but it is still interesting, seems this area is likely to be a center of activity for a while now.

      Might just be better angles but the start of this eruption looked a lot more intense than the last one and it has been persistent at a higher rate for longer with less actual effect on the deformation. the GPS has only fallen to the value it had a month ago, it is still going down and might for a while but in 2020 the drop in the equivalent time period (1 week) was basically almost half a years worth of inflation that was already at an elevated rate from the long term anyway. Seems there is a serious magma surge going on, well in excess of the long term hotspot rate.

      Maybe that deep Pahala stuff that had been collecting for the last 3 years has finally found its outlet.

      • Actually, now that I think about it, the last 3 years might have been magma escaping Pahala, maybe drawn there by the big deflation in 2018.

        How long magma has been accumulating under Pahala, who knows but it could have been decades, maybe at least since 1950, and now it is finally free and starting to erupt… Will be very interesting to find out what the new lava composition is, if there is some deeper element.

        • Is it just me, or did the Pahala quake swarm become less active when the current eruption commenced? Based on looking at the Kilauea monitoring map a couple of times a day, it did – but that might be just my perception.

          And I very much agree; an analysis of the lava might prove very interesting indeed.

  15. Iceland. Looking at today’s charts I think it may not be long before we find out what all the fuss has been about at Keilir. It looks like stuff is on the move and may be at the 2km down area now.
    I eagerly wait to see if my 9 October 1:19pm prediction will be right. Meanwhile, the eggs are ready…

      • Yes I got overenthusiastic about 2km. That was an unconfirmed. Nonetheless, progress is upwards. Slowly.

        Friday
        08.10.2021 01:54:27 63.917 -22.237 2.7 km 1.0 99.0 2.4 km NE of Fagradalsfjall

        Friday
        08.10.2021 01:54:27 63.917 -22.237 2.7 km 1.0 99.0 2.4 km NE of Fagradalsfjall

        Friday
        08.10.2021 00:46:48 63.927 -22.188 4.8 km 0.7 99.0 1.8 km SSW of Keilir

        Thursday
        07.10.2021 05:57:58 63.926 -22.187 4.8 km 0.8 99.0 1.9 km SSW of Keilir

        Thursday
        07.10.2021 01:53:32 63.935 -22.196 3.5 km 1.0 99.0 1.4 km WSW of Keilir

    • They don’t mention when this is registered.
      It shows a wall of lava working down the slopes.

      The Copernicus mapping is not able to process new maps due the haze and ash preventing usable satellite data.

      • Just checked the Spanish message under this drone video. Google translates as:-
        Reconnaissance flight carried out last night by the drone of the Emergency and Rescue Group (GES) of the Government of the Canary Islands, with the thermographic camera
        So assuming that was definitely last nights video.

          • The Spanish government, ergo the Canaries government and not so forgiving of misuse of their information as the wonderful world of Oz. You can be *sure* it was lastnight.

    • Eruption/activity update – During the past hours, the eruption has been becoming stronger, our correspondent Victor from the Canarian volcanological society Volcanes de Canarias reported.
      Strong ground vibrations can be felt

      • This video appears to capture the start of that massive lava flow last night and it is easy to see that the cone wall breaks to cause that massive flood of lava.

  16. Looking at the following daytime drone video, posted 2 hours ago, it looks like there will soon be another ocean entry for the lava in La Palma.

  17. Last la palma earthquakes
    3.7 M(mb) SW VILLA DE MAZO.ILP 2021/10/08 13:20:56 40 +info
    3.2 mbLg SW VILLA DE MAZO.ILP 2021/10/08 13:19:30 14 +info
    3.5 mbLg NE FUENCALIENTE DE LA PALMA.IL 2021/10/08 12:58:16 II-III 13 +info
    2.8 mbLg NE FUENCALIENTE DE LA PALMA.IL 2021/10/08 12:53:34 13 +info

    • 3.7 M(mb) SW VILLA DE MAZO.ILP
      2021/10/08 13:20:56
      40

      +info
      3.7 M(mb) SW VILLA DE MAZO.ILP
      2021/10/08 13:20:55
      41

      +info
      3.5 mbLg NE FUENCALIENTE DE LA PALMA.IL
      2021/10/08 12:58:16II-III
      13

      +info
      2.8 mbLg

      NE FUENCALIENTE DE LA PALMA.IL
      2021/10/08 12:53:34
      13

      +info
      3.7 mbLg N FUENCALIENTE DE LA PALMA.ILP
      2021/10/08 12:46:00III
      13

      • Some large (for volcanic) quakes in that list and very close together also. Looks like a lot more activity to come from this volcano.

        • Just noted that SO increased to 13.100 tons/day according to the livestream. If I am correct last week it was ~8000 tons/day.

  18. stream is going dark mid day. I hope this is gear malfunction not some climactic event..

    • OOPS sorry!!! That is too close to the building there so it is the original lava flow. The new one, assuming it makes it fully to the sea, is further South (left of the current flow seen from the sea.) and already flowing down the cliffs but plantations below before it reaches the sea.

  19. About the sequence of the La Palma eruption.

    Caught at twitter this interesting animation of the quakes, starting 13 09 ending 08 10.
    Unrest started between 7 – 10 km propagating to the surface cleary until eruption. So far so good.
    After the eruption started, unrest continued, but deeper: between 10 – 15 km.
    Also a patch much deeper, 30 ish km.

    I didn’t read any discussion about the deepening of the quake activity in time.
    Could it be due to pressure changes, mobilization of more magma?
    Is the deepening something that happens often during eruptions?

    The 10 -15 km are quite large, no minor detected. Aren’t minors not recorded at this depth?

    Please let hear your thoughts.

    https://twitter.com/i/status/1446486181248704523

    • These earthquakes are an interesting subject. Normaly the quakes tend to subside after the start of an eruption. On La Palma the seismicity increased after the start of the eruption, in particular after the eruption had taken a short break. The only way I can explain this is that the pressure relief caused the moving of the magma in the depth and rising towards the surface. The pressure relief also causes movements in the surrounding rock. There should be two storage areas. One at a depth of approx. 10 – 15 km and one at approx. 35 km, as you can see from the clusters. We must not forget that the last eruption on La Palma was 50 years ago and that, back then, the monitoring of seismic activity was nowhere near as advanced as it is today. So we know little about the seismic behavior of this volcano. This also applies to the rest of the Canary Islands. I think the scientists will learn a lot by this eruption.

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