December 09 , 2020.

La Réunion , Piton de la Fournaise :

Activity Bulletin for Wednesday 9 December at 9:15 (local time)
Alert level: Backup

Following the end of the eruption on 12/08/2020 around 7:15 a.m. local time, 21 volcano-tectonic earthquakes were recorded during the day of 12/08/2020 under the western edge of the Dolomieu crater, at 900 m approximately above sea level (ie approximately 1700 m below the surface), and already 6 today (between 0 a.m. and 5 a.m. UT, i.e. until 9 a.m. local time).

A possible resumption of inflation (swelling) of the edifice will be followed in the coming days.

The gas emissions in the air or in the ground have returned to pre-eruptive conditions, namely CO2 fluxes in the stable soil and SO2 emissions in the air at the level of the summit of the volcano below or near the threshold detection.

Source : OVPF.

Read the article : http://www.ipgp.fr/fr/ovpf/bulletin-dactivite-mercredi-9-decembre-a-915-heure-locale

Photo : Tunnels de lave Réunion : Rando-Volcan via Facebook. ( randovolcan@gmail.com  ) 

Indonesia ,  Sinabung :

The activity level has been at level III (SIAGA) since May 20, 2019 at 10:00 a.m. Mount Sinabung (2460 m above sea level) has been erupting since 2013.

The volcano was clearly visible until it was covered in fog. It was possible to observe the crater with white smoke, of high intensity about 100 to 300 meters above the summit. Avalanches were observed with a sliding distance of 500 to 1000 meters to the Southeast. The weather is sunny to cloudy, with weak to moderate winds to the east and southeast. The air temperature is around 16-27 ° C.

According to the seismographs of December 8, 2020, it was recorded:
70 avalanche earthquakes
13 low frequency earthquakes
9 hybrid / multi-phase earthquakes
1 distant tectonic earthquake.

Recommendation:

The public and visitors / tourists should not carry out activities in the villages that have been relocated, as well as within a radial radius of 3 km around the summit of G. Sinabung, and within a sector radius of 5 km for the sector. South-East and 4 km for the North-East sector.
In the event of ash rain, people are advised to wear masks when leaving the house to reduce the health effects of volcanic ash. Secure drinking water facilities and clean the roofs of houses from dense volcanic ash so that it does not collapse.
People who live near the rivers that flow from Mount Sinabung should be aware of the dangers of lahars.

VONA: The last VONA message was sent with the color code ORANGE, published on December 2, 2020 at 08:01:00 WIB. Volcanic ash was observed at an altitude of 2,960 m above sea level or 500 m above the summit.

Source : PVMBG.

Photo : Firdaus Surbakti.

Iceland , Reykjanes Peninsula :

Around 410 earthquakes were located by the IMOs SIL seismic network this week, fewer than the previous week when around 450 earthquakes were located. The largest earthquake of the week was a M3.6 just east of Þorbjörn on the Reykjanes peninsula the 1.st of December at 11:23.

The earthquake was felt in the nearby town of Grindavík. That same day at 20:40 a M3.5 occurred around 70km SW of the Reykjanes peninsula. The 2.nd of December at 11:28 a M3.1 occurred 20 km SE of Grimsey island just north of Iceland. One minor earthquake was located in Hekla during the week.

Source : Vedur .

Chile , Nevados of Chillan :

Special report of volcanic activity (REAV), Region of Ñuble, volcanic complex of Nevados de Chillán.
December 09, 2020 at 12:50 a.m. local time (Continental Chile).

The National Geological and Mining Service of Chile (Sernageomin) publishes the following PRELIMINARY information, obtained thanks to the monitoring teams of the National Volcanic Monitoring Network (RNVV), processed and analyzed at the Volcanological Observatory of the Southern Andes (Ovdas):

On Wednesday 09 December at 00:19 local time (03:19 UTC), the monitoring stations installed near the Nevados de Chillán Volcanic Complex recorded an earthquake associated with the fracturing of rocks (Volcano-Tectonic).

The characteristics of the earthquake after its analysis are as follows:
ORIGINAL TIME: 00:19 local time (03:19 UTC)
LATITUDE: 36,887 ° S
LONGITUDE: 71 361 ° W
DEPTH: 4.3 km
LOCAL MAGNITUDE: 3.0 (ML)

OBSERVATIONS:
No superficial activity related to the reported event is recorded.
The volcanic technical alert remains at the YELLOW level.

Source : Sernageomin .

Photo : Archive.

Colombia , Nevado del Ruiz : 

Bulletin of extraordinary activity of the Nevado del Ruiz volcano. 03 December 2020 (14:15 HL).
The level of yellow activity is maintained or (III): changes in the behavior of volcanic activity.

Regarding the monitoring of the activity of the Nevado del Ruiz volcano, the COLOMBIAN GEOLOGICAL SERVICE reports that:
Since the evening of December 3 and until the publication of this bulletin, an increase in seismic activity of the « drumbeat » type has been recorded. During the night and in the early morning, there were several episodes of this type of seismicity characterized by volcano-tectonic earthquakes, associated with fractures of rocks around the volcanic building. This morning, since 09:42 (local time), this type of seismicity is constant and is characterized by earthquakes linked to the dynamics of the fluids inside the volcanic conduits. In general, these seismic events are of a very low energy level.

This « drumbeat » type seismicity has been linked to the processes of ascent, location, growth and evolution of a lava dome at the bottom of the Arenas crater of the Nevado del Ruiz volcano.
The Nevado del Ruiz volcano continues at the yellow activity level. It is not excluded that there is an activity that may indicate an acceleration of the process, involving greater instability of the volcano and consequently changes in its level of activity. Although the instability of the volcano has lasted for more than ten years, It is extremely important not to get used to its behavior and to be attentive to the official information that will be published by the Colombian Geological Survey.

Seismicity generated by fracturing of rock increased in the number of earthquakes and in the seismic energy released, compared to the previous week. This seismic activity was localized mainly in the North-East, East-North-East, South-South-West sectors, in the Arenas crater, and to a lesser extent in the West sector, at depths between 0.6 and 7 , 0 km. The highest magnitude recorded during the week was 1.6 ML (local magnitude), corresponding to the earthquake that occurred on December 2 at 2:57 a.m. (local time), located 0.8 km north – East of the Arenas crater, at a depth of 1.4 km.

Source : SGC.

Photo : Diana M Bustamante.