Overblog
Editer l'article Suivre ce blog Administration + Créer mon blog

Earth of fire

Actualité volcanique, Articles de fond sur étude de volcan, tectonique, récits et photos de voyage

Publié le par Bernard Duyck
Publié dans : #volcanic activity
  Fagradalsfjall - the active cone and the lava flow on 06.20.2021 / 02:19 - RUV webcam - one click to enlarge

 Fagradalsfjall - the active cone and the lava flow on 06.20.2021 / 02:19 - RUV webcam - one click to enlarge

Three months after the start of the Fagradalsfjall eruption, scientists are giving their impressions.

Several factors make the eruption exceptionally interesting, say Magnús Tumi Guðmundsson, geophysicist and Kristín Jónsdóttir, seismologist:

- It is the beginning of a new period of eruption on the Reykjanes peninsula, for 800 years.

- The behavior of the eruption is different: after a very calm start, the lava flow increased to double three months later. Lava filled valleys and depressions and flows around hyaloclastite mounts, formed during subglacial eruptions.

- Fueled by a deep magma coming from the mantle, the eruption could last a long time (from a few years to decades) ... this type of eruption has hardly been observed since the end of the Ice Age at this place, 6,000 years ago.

The bend of the lava tongue that flows into Nátthaga from the southwestern part of Geldingadalur .--- and the protective wall to prevent flow to Nátthagakrik - Doc. Fréttablaðið - Almannavarnir 06.18.2021 - one click to enlarge
The bend of the lava tongue that flows into Nátthaga from the southwestern part of Geldingadalur .--- and the protective wall to prevent flow to Nátthagakrik - Doc. Fréttablaðið - Almannavarnir 06.18.2021 - one click to enlarge

The bend of the lava tongue that flows into Nátthaga from the southwestern part of Geldingadalur .--- and the protective wall to prevent flow to Nátthagakrik - Doc. Fréttablaðið - Almannavarnir 06.18.2021 - one click to enlarge

Fagradalsfjall elgos - In red: The magma today. - in green: The fort. - The purple lines: Possible paths of the lava. There is a risk that it will accumulate on the turn towards Nátthaga and throw itself into Nátthagakrik. The Magma Path also leads to Nátthaga towards Suðurstrandarvegur. Doc. Frettablaðið 18.06.2021 - one click to enlarge

Fagradalsfjall elgos - In red: The magma today. - in green: The fort. - The purple lines: Possible paths of the lava. There is a risk that it will accumulate on the turn towards Nátthaga and throw itself into Nátthagakrik. The Magma Path also leads to Nátthaga towards Suðurstrandarvegur. Doc. Frettablaðið 18.06.2021 - one click to enlarge

No construction work will be done to prevent lava from Geldingadalur from flowing onto Suðurstandarvegur, but the focus will be on protecting the town of Grindavík and the roads surrounding it, according to an announcement by the National Civil Defense Commissioner .

A four meter high and 200 meter long retaining wall is the only thing preventing lava from flowing into Nátthagakrik, from where there is an easy path north, west and south to Suðurstrandarvegur , Grindavík, Svartsengi and Grindavíkurvegur.

 

Sources: interview in RUV & mbls

From 6.15 p.m. on 06.19.2021, a Strombolian activity began at the level of the south-eastern crater of Etna. This activity is accompanied by a modest emission of ash. From 6.30 p.m. a southwest-directed lava overflow began, and from around 6.40 p.m. UTC, a sudden increase in Strombolian activity was observed at the south-eastern crater, which produced a continuous emission of ashes. On the basis of the forecast model, the emission of ash and lapilli is dispersed in the direction of Tremestieri Etneo, Mascalucia, Nicolosi, Catania and the regions further south.
The center of gravity of the volcanic tremor sources is located in the southeastern crater region at an altitude of about 2900-3000 m above sea level.

Etna SEC - lava fountain on 06/19/2021 / 8:59 p.m. - new webcam LAVE

Etna SEC - lava fountain on 06/19/2021 / 8:59 p.m. - new webcam LAVE

From 19:00 UTC, the Strombolian activity in the southeast crater turned into a lava fountain. Based on the forecast model, the eruptive cloud produced by the current activity disperses in the S direction. The effusive activity produced by the lava overflow in the southwest direction continues to be well fed.


According to the images of the surveillance cameras, around 19:30 UTC, we observe that the explosive activity at the Southeast crater has ceased, the lava overflow that extends in a southwest direction is still active.

 

Source: INGV OE

Etna SEC - 06.19.2021 / 9:29 p.m. - new webcam LAVE

Etna SEC - 06.19.2021 / 9:29 p.m. - new webcam LAVE

Etna - trémor at 20.06.2021 / 05h - Doc. INGV OE

Etna - trémor at 20.06.2021 / 05h - Doc. INGV OE

At Stromboli, a lava overflow, which began at 5:15 pm UTC, occurred in conjunction with explosive activity in the northern sector; the lava front cools and affects the upper part of the Sciara del Fuoco.

The trend of the mean amplitude of the volcanic tremor does not show significant changes and the values ​​remain at the average level. GNSS networks and tiltmeters show no significant changes. The TDF incline station data is updated at 16:30 UTC.

 

Source: INGV OE

Stromboli - 19.06.2021 / 20:03 - lava flow in the upper part of the Sciare del Fuoco - INGV webcam

Stromboli - 19.06.2021 / 20:03 - lava flow in the upper part of the Sciare del Fuoco - INGV webcam

The eruption, which began on June 29, 2014 in Manam, Papua New Guinea, continues.

Monitoring is episodic depending on the weather, the rate of satellite photos and measurements of thermal anomalies.

A clearer sky on June 18, 2021 showed a slight hot spot, degassing of steam (white) and sulfur gas (bluish plume).

 

Sources: Sentinel-2 & Mirova

Manam - gas and steam plumes & hot spot on 06/18/2021 - image Sentinel-2 bands 12,11,4

Manam - gas and steam plumes & hot spot on 06/18/2021 - image Sentinel-2 bands 12,11,4

Manam - thermal anomalies at 06.18.2021 - Doc. Sentinel-2 bands 12,11,8A & MODIS thermal volcanic activity - via Mirova

Manam - thermal anomalies at 06.18.2021 - Doc. Sentinel-2 bands 12,11,8A & MODIS thermal volcanic activity - via Mirova

Commenter cet article

Articles récents

Hébergé par Overblog