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
Piton de La Fournaise - image Sentinel-2 L1C image bands 12,11,4 from 10.08.2019 - one click to enlarge

Piton de La Fournaise - image Sentinel-2 L1C image bands 12,11,4 from 10.08.2019 - one click to enlarge

Since 07:00 local time, a seismic crisis is recorded on the instruments of the Volcanological Observatory of Piton de la Fournaise. This seismic crisis is accompanied by rapid deformation. This indicates that the magma is leaving the magma reservoir and is spreading to the surface.

Between 7:00 and 15:00 local time 1162 volcano-tectonic earthquakes were recorded by the OVPF network.

Piton de La Fournaise - Histogram of volcano-tectonic earthquakes under the volcano recorded on August 11, 2019 between 00h and 11h UTC time (15h local time). (© OVPF / IPGP)

Piton de La Fournaise - Histogram of volcano-tectonic earthquakes under the volcano recorded on August 11, 2019 between 00h and 11h UTC time (15h local time). (© OVPF / IPGP)

After 9:30 of seismic crisis, the volcanic tremor, synonymous with the arrival of the magma close to the surface, is registered since 16h20 local env. on the instruments of the OVPF / IPGP

The deformations and the seismicity show that the magma has spread deep from the southeastern edge of Dolomieu crater towards the east flank, southeast.

At present (4:00 pm local time), the spread continues in this direction.

The source of this tremor is located on the eastern flank, southeast, inside the Enclos Fouqué, in the sector of the Great Slopes / les Grandes Pentes.

Piton de La Fournaise - Variations of slope (in microradians) recorded on the summit inclinometer network of the OVPF between August 10th and August 11th 10am (UTC time, 14h local time) 2019. The direction taken by the deep magma is indicated by the arrow. The colored bar represents the time in the last 36 hours. The white circle indicates the approximate location of the pressure source at depth to explain the slope variations recorded at the beginning of the crisis (white arrows). The black circle indicates the approximate location of the pressure source at depth to explain the slope variations recorded around 13h-14h (black arrows). (© OVPF / IPGP)

Piton de La Fournaise - Variations of slope (in microradians) recorded on the summit inclinometer network of the OVPF between August 10th and August 11th 10am (UTC time, 14h local time) 2019. The direction taken by the deep magma is indicated by the arrow. The colored bar represents the time in the last 36 hours. The white circle indicates the approximate location of the pressure source at depth to explain the slope variations recorded at the beginning of the crisis (white arrows). The black circle indicates the approximate location of the pressure source at depth to explain the slope variations recorded around 13h-14h (black arrows). (© OVPF / IPGP)

No visual confirmation of a start of eruption could be made at 16:04 UTC on webcams due to poor weather conditions and we can not confirm the arrival of lava on the surface. Nevertheless the presence of a tremor shows the emission of hot and incandescent gas on the surface, and the possibility of lava emission in the short term or already in progress.

Under these conditions, the Prefect decided to implement the alert phase 2-2 "eruption underway in the Fouqué enclosure" of the specific device ORSEC volcano this Sunday, August 11, 2019 at 17:15

Public access to the Fouqué enclosure, from the Pas de Bellecombe trail or from any other trail, as well as from aircraft in the volcano area, are prohibited until further notice.

 

Sources:

- OVPF - activity bulletins of the day

Find all the information related to the Piton de la Fournaise activity on the different media of the OVPF-IPGP:

- the website (http://www.ipgp.fr/fr/ovpf/actualites-ovpf),
- the Twitter account (https://twitter.com/obsfournaise?lang=en),
- and the facebook account (https://www.facebook.com/ObsVolcanoPitonFournaise/)

- Prefecture of Reunion

Commenter cet article

Articles récents

Hébergé par Overblog