Eruptions

News about eruptions and volcanoes can be found in this category. It is updated frequently. Volcano expert and journalist Marc Szeglat reports live from his expeditions to volcanoes.

Shiveluch: Egg-shaped dome grows

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A photo of an unusual lava dome was taken at the Shiveluch in Kamchatka (Russia). The dome looks like a grey egg and has a very smooth surface. KVERT researchers suspect that it is a dome of dacitic lava. The structure already has a name: Dolphin. Locally one associates less an egg than a dolphin back. The first signs of the formation of a new dome were already seen in May, but the dolphin experienced its greatest growth in the last 4 months. Since then it has also been unusually quiet on the Shiveluch and only occasionally a slight thermal radiation was registered. Should the egg-shaped dolphin collapse, a very strong eruption will occur along with large pyroclastic flows. Then you should not stay near the volcano!

Piton Fournaise: Further earthquakes

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At the Piton de la Fournasie, further earthquake activity was registered, although the actual seismic crisis was declared over yesterday. Seismologists report 8 volcano-tectonic earthquakes near the surface and 35 volcano-tectonic earthquakes at greater depths below the eastern flank. Furthermore, 1 long-periodic earthquake, 14 earthquakes classified as “undetermined” and 52 superficial landslides or collapse events occurred in the area of the eastern flank. 144 events of smaller magnitude were detected automatically. Inflation is also continuing, although at a much lower level than in the days of the crisis. At one measuring station a total ground elevation of 23 cm was registered. The horizontal offset was 76 cm. The scientists still consider an eruption possible, even though the probability of this has decreased.

Etna erupts strombolian

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Strombolian eruption. © Gio Giusa

Yesterday Etna erupted strombolian and produced very aesthetic lava fountains. The ejection height of incandescent tephra was not very high, but a lot of incandescent material was erupted, so that the fountains were very voluminous. Some Etna photographers were in the summit area and documented the event in respectable photos.

In addition, a sentinel satellite photo shows a correspondingly strong thermal anomaly in the active saddle vent of the New South East Crater, which was the site of the eruptions. MIROVA recorded a high thermal radiation of 121 MW. A smaller hotspot is visible in the Northeast Crater. The tremor fluctuated at a high level. The day before, 14 weak tremors were recorded by the seismometers of the INGV. Many quakes were located near Refugio Citelli.

As always, it is difficult to make a forecast about the further behavior of the volcano. The data indicate that the current status has stabilized and we will continue to see mild summit activity. Furthermore, more magma seems to accumulate underground than is erupted.Etna continues to draw strength.

Grimsvötn: Yellow alert declared

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The Icelandic glacier volcano Grimsvötn is preparing for an eruption and IMO has declared the VONA warning level “yellow”. A strong eruption could occur at any time, which could pose a danger to air traffic. In fact, there are still very few aircraft movements, as most of the airplanes remain on the ground due to the pandemic, but caution is the mother of the porcelain box, as is well known.

Various parameters changed in the last months at Grimsvötn. IMO gives the following reasons for the increase of the warning level:

  • The seismicity during the past month has been above average
  • Geothermal activity has increased over the past months with clear signs of deepening cauldrons in several places around the caldera
  • The surface deformation has exceeded the level it was at prior to the 2011 eruption
  • Magmatic gases were measured in the geothermal emissions this summer.
  • The water level in subglacial caverns is as high as before the 2004 glacier flood.

All in all, this is not a surprising development, but a continuation of the trends that were already reported in summer. The exact time frame when the eruption will occur cannot be estimated. It could happen in the next few days, but it could also take several weeks or months.

For many volcano spotter the question is of course how to get to Iceland? In general, trips to Iceland are possible, but people entering the country will have to stay in quarantine for 5-6 days if they get tested twice. The first test is done upon entry, the second test after 5 days. If you do not want to be tested, you have to be in quarantine for 14 days. During the quarantine you must stay in your hotel room. This practically nips any attempt to catch the outbreak in the bud, unless you leave now and wait for the outbreak. If you do not leave until the eruption begins, you will probably be too late at the volcano.

Etna: more earthquakes

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Etna in Sicily remains exciting, because further earthquakes occurred. A quake M 2.0 can be attributed to the swarm quake in the northeast. Yesterday the INGV registered a total of 27 earthquakes on Etna. This was the highest number for months, if not since the eruption of 24.12.2018. Many of the earthquakes also occurred under the Valle del Bove, not far from the Northeast Crater.

In the northwest there was an earthquake today with a magnitude of 3.2, the epicenter was located 1 km from Bronte. The depth of the hypocenter is indicated as 10 km. Even if the quakes are of tectonic origin, they could still be caused by a changed stress environment due to magma rise. I assume that some magma is accumulating under the volcano.

Piton Fournaise: No eruption yet

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At the Piton de la Fournaise, there has not been a volcanic eruption so far, although the seismic crisis lasted for hours and may still continue. The last report of the volcanologists of the OVPF is from yesterday evening 21.30 local time. There it says that the seismic crisis continues. Since noon more than 2000 earth tremors have been registered. The inflation under the summit crater was 360 microrad and migrated eastwards. The director of the observatory, Aline Peltier, expressed her concern. Such long lasting seismic crises are unusual and she did not exclude that an eruption fissure could open relatively far down the eastern flank of the volcano. However, there is also the possibility that the magma might get stuck in the underground and not erupt at first. So it remains exciting at Piton de la Fournaise on La Réunion.

Piton Fournaise: Seismic crisis on 28.09.20

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At the Piton de la Fournaise a seismic crisis set in. Numerous weak tremors were registered. They were accompanied by rapid inflation: magma rose and sought its way to the surface. Access to the caldera was closed and an eruption is expected. However, it is still possible that the magma will stuck in the ground.

The last eruption occurred between 10 and 16 February this year.

Etna: Earthquake swarm in the northeast

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Yesterday evening an earthquake swarm manifested on Etna’s northeast flank. The INGV reports 8 earthquakes with magnitudes from 2. The two strongest quakes were on M 3.2. The epicenters were located 5 km southwest of Linguaglossa. The hypocenters were very flat. The depths vary between 0 and 1 km. This is very unusual, normally the quakes are at least 4-5 km deep. The INGV does not indicate how many weaker quakes there have been for 2 days.

Probably they are tectonically caused earth tremors along the Pernicana fault system. Quakes here are not new. In the past they often signaled that Etna is preparing for a major eruption. However, it is not really possible to narrow down the time frame when an eruption is likely to occur.

The best known example happened in 2002. On September 22nd there was an earth tremor of magnitude 3.7. On October 26th a massive swarm quake started. One day later the flank eruption started. A scenario that could repeat itself at any time, even if the probability is not very high.

Etna with ash cloud

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Yesterday afternoon Etna erupted an ash cloud. The eruption lasted longer. Strong winds pushed the eruption cloud down and blew it towards the southeast and into the Valle del Bove. MIROVA reported a slight thermal anomaly. The tremor fluctuated strongly. This morning there was an earthquake of magnitude 2.0 in the northwest of the volcano. Several weak earthquakes have already been recorded in the last few days.

Pacaya increases activity on 26.09.20

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Yesterday evening there was a sudden increase in activity at the Guatemalan volcano Pacaya. Strombolian eruptions came in short intervals and transported glowing tephra up to 70 m high. A new lava flow began to flow again, which quickly covered a distance of 200 m. The activity was accompanied by tremors. A few hours earlier INSIVUMEH reported strombolinaceous eruptions, but not an active lava flow.

During my visit to the volcano in January of this year I also witnessed how quickly the situation at Pacaya can change: suddenly a vent on the south side of the Mc Kenney cone opened and produced a short lava flow. A little later a flow on the north side became active. After a few minutes everything was over again. Such events illustrate the unpredictability of volcanoes.