November 12, 2020. EN. India / Andaman Islands : Barren Island , Japan : Sakurajima , Costa Rica : Turrialba / Poas / Rincon de la Vieja / Irazu , Chile : Laguna del Maule .

November 12 , 2020.


India / Andaman Islands : Barren Island ,

The Darwin VAAC reported that an eruption at Barren Island on 5 November produced ash plumes that rose 1.5 km (5,000 ft) a.s.l. and drifted SW and WSW.

An ash plume in 1991 rises above Barren Island along the volcanic arc connecting north of Sumatra. The 3-km-wide island contains a 1.6-km-wide crater that is partially filled by a scoria cone that has been the source of eruptions since the first was recorded in 1787. Lava flows reached the coast during several recent eruptions.

Barren Island, a possession of India in the Andaman Sea about 135 km NE of Port Blair in the Andaman Islands, is the only historically active volcano along the N-S volcanic arc extending between Sumatra and Burma (Myanmar). It is the emergent summit of a volcano that rises from a depth of about 2250 m. The small, uninhabited 3-km-wide island contains a roughly 2-km-wide caldera with walls 250-350 m high. The caldera, which is open to the sea on the west, was created during a major explosive eruption in the late Pleistocene that produced pyroclastic-flow and -surge deposits. Historical eruptions have changed the morphology of the pyroclastic cone in the center of the caldera, and lava flows that fill much of the caldera floor have reached the sea along the western coast.

Source : GVP , Darwin Volcanic Ash Advisory Centre (VAAC).

Photo : D. Haldar, 1991 (Geological Survey of India).


Japan , Sakurajima :

JMA reported that during 2-9 November incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. Two explosions during 1-2 November produced ash plumes that rose as high as 1.8 km above the crater rim. An explosion was recorded at 1504 on 7 November but the weather conditions prevented visual conformation. The daily sulfur dioxide emission rate was high at 2,200 tons per day on 9 November. The Alert Level remained at 3 (on a 5-level scale).


The Aira caldera in the northern half of Kagoshima Bay contains the post-caldera Sakurajima volcano, one of Japan’s most active. Eruption of the voluminous Ito pyroclastic flow accompanied formation of the 17 x 23 km caldera about 22,000 years ago. The smaller Wakamiko caldera was formed during the early Holocene in the NE corner of the Aira caldera, along with several post-caldera cones. The construction of Sakurajima began about 13,000 years ago on the southern rim of Aira caldera and built an island that was finally joined to the Osumi Peninsula during the major explosive and effusive eruption of 1914. Activity at the Kitadake summit cone ended about 4850 years ago, after which eruptions took place at Minamidake. Frequent historical eruptions, recorded since the 8th century, have deposited ash on Kagoshima, one of Kyushu’s largest cities, located across Kagoshima Bay only 8 km from the summit. The largest historical eruption took place during 1471-76.

Source:Japan Meteorological Agency (JMA) , GVP.

Photo : 8nov19 , @volcanohull / public domain / Volcanodiscovery


Costa Rica , Turrialba / Poas / Rincon de la Vieja / Irazu :

Weekly bulletin, November 9, 2020.

Turrialba volcano
Lat: 10.025 ° N; Long: 83.767 ° W;
Height: 3340 m.s.n.m.
Current activity level: 2 (active volcano)
Potentially associated hazards: gas, ash emission, proximal ballistic projections.

No ash emission was observed. The seismic activity remains high with LP type events and short tremors. Geodetic observations continue to detect horizontal contraction of the Turrialba-Irazú massif, and they have noted significant deflation in recent days. Gas ratios or SO2 flow could not be measured due to unfavorable wind direction.
No thermal anomaly was detected by the MODIS analysis. The high level of seismicity is interpreted as infiltration of rainwater into the building, which, if confirmed, could produce small ash emissions and groundwater eruptions capable of proximal ballistic projections.

Poas volcano
Lat: 10.2 ° N; Long: 84.233 ° W;
Height: 2780 m.s.n.m.
Current activity level: 2 (active volcano)
Potentially associated hazards: gas, phreatic eruptions, proximal ballistic projections.

No eruption was detected. The seismic activity continues with more permanent background tremors of varying amplitude. Inflation observed by geodetic monitoring since August has decreased, now it is no longer significant. The H2S / SO2 ratio remains high and the SO2 / CO2 ratio remains low. These measurements are consistent with the observation of elemental sulfur floating in the lake during the week. The SO2 flux could not be measured due to an unfavorable wind direction. The level of the lake rose 1.4 m in one week due to heavy rainfall (~ 450 mm under the influence of Hurricane Eta). Evaporation / infiltration rate has decreased. No thermal anomaly was detected by the MODIS analysis.

Rincon de la Vieja volcano
Lat: 10.83 ° N; Long: 85.324 ° W;
Height: 1895 m.s.n.m.
Current activity level: 3 (erupting volcano)
Potentially associated hazards: gas, phreatic eruptions, proximal ballistic projections, lahars.

Seismic activity is low. The eruptions are more sporadic but with a greater amplitude. Geodetic monitoring shows a significant narrowing of the summit of the volcano.
No thermal anomaly was detected by the MODIS analysis.

At 5:40:00 local time on November 11, 2020, an eruption was recorded on the Rincon de la Vieja volcano, with a column that rose 1,000 meters above the height of the crater and 2,916 meters above above sea level (9,564.48 ft).
Duration of activity: 5 minutes.

Irazu volcano
Lat: 9.979 ° N; Long: 83.852 ° W;
Altitude: 3432 m.s.n.m.
Current activity level: 1 (active)
Potentially associated hazards: landslides.

Seismic monitoring detected a significant landslide on November 4 with a lahar-type flood (mud runoff). The main landslide in the western sector of the volcano presented a vertical acceleration during the weekend, without being associated with an acceleration on the horizontal components. MODIS satellite analysis detected a small thermal anomaly on November 4.

Source : Ovsicori .


Chile , Laguna del Maule :

SERNAGEOMIN reported that 10 low-magnitude volcano-tectonic earthquakes were detected at the Laguna del Maule Volcanic Complex during 16-31 October; seismicity was low in the region where a swarm had occurred in June. Satellite data showed no deformation, surface changes, gas emissions, or thermal anomalies. On 6 November the Alert Level was lowered to Green, the lowest level on a four-color scale. ONEMI cancelled the Yellow Alert for San Clemente, but declared a “Preventive Early Warning” ensuring continued surveillance of the area and coordination within the Civil Protection System.

– 10 seismic events classified as volcano-tectonic (VT) were recorded, associated with fracture processes of rigid materials in volcanic systems. No event presented a level of energy to locate it.
– The images provided by the IP camera installed near the complex did not record any surface activity associated with the volcanic system.
– Thanks to the analysis of Sentinel L2 A and Planet Scope satellite images, no surface or morphological variation is observed. There are also no variations in temperature or radiances associated with thermal anomalies, according to the LandSat 8 OLI TIIRS and Sentinel L2 A image processing.

– No anomalies were reported in the emissions of sulfur dioxide (SO2) into the atmosphere in the area near the volcanic complex, according to data published by the Tropospheric Monitoring Instrument (TROPOMI) and the Ozone Monitoring Instrument (OMI ) Sulfur Dioxide Group (http: //
– During the period, no thermal alert was recorded in the area associated with the volcanic complex, according to data processed by Middle Infrared Observation of Volcanic Activity (MIROVA) and by temporal thermal monitoring of global hot spots (MODVOLC) (
– Data for the geodesic assessment of the volcanic complex was not available due to problems originally. The interferometric data make it possible to detect behavior similar to that observed historically in the area, without evidence of notable changes in the behavior of the complex.

Despite the recording of low energy seismic activity in the area where the seismic swarms occurred in June of this year, no new high seismic recurrence events were observed in the area. The above, along with the analysis of satellite images, where no variation or surface anomaly is observed, suggests stability in the volcanic complex.

The above allows to change the volcanic alert level to:
GREEN TECHNICAL ALERT: Active volcano with stable behavior – No immediate risk.

Source : GVP , Sernageomin .

Photo : Oscar González-Ferrán (University of Chile)

12 Novembre 2020. FR. Inde / Iles Andaman : Barren Island , Japon : Sakurajima , Costa Rica : Turrialba / Poas / Rincon de la Vieja / Irazu , Chili : Laguna del Maule .

12 Novembre 2020.


Inde / Iles Andaman : Barren Island ,

Le Darwin VAAC a rapporté qu’une éruption à Barren Island le 5 novembre a produit des panaches de cendres qui se sont élevés de 1,5 km (5000 pieds) d’altitude. et ont dérivé vers le Sud-Ouest et l’Ouest-Sud-Ouest .

Un panache de cendres en 1991 s’élève au-dessus de l’île Barren le long de l’arc volcanique reliant le Nord de Sumatra. L’île de 3 km de large contient un cratère de 1,6 km de large qui est partiellement rempli par un cône de scories qui a été la source d’éruptions depuis la première enregistrée en 1787. Des coulées de lave ont atteint la côte lors de plusieurs éruptions récentes.

Barren Island, une possession de l’Inde dans la mer d’Andaman à environ 135 km au Nord-Est de Port Blair dans les îles Andaman, est le seul volcan historiquement actif le long de l’arc volcanique Nord-Sud  s’étendant entre Sumatra et la Birmanie (Myanmar). C’est le sommet émergent d’un volcan qui s’élève d’une profondeur d’environ 2250 m. La petite île inhabitée de 3 km de large contient une caldeira d’environ 2 km de large avec des murs de 250 à 350 m de haut. La caldeira, ouverte sur la mer à l’Ouest, a été créée lors d’une importante éruption explosive à la fin du Pléistocène qui a produit des coulées pyroclastiques et des dépôts de surges . Les éruptions historiques ont changé la morphologie du cône pyroclastique au centre de la caldeira et les coulées de lave qui remplissent une grande partie du fond de la caldeira ont atteint la mer le long de la côte Ouest.

Source : GVP , Darwin Volcanic Ash Advisory Centre (VAAC).

Photo : D. Haldar, 1991 (Geological Survey of India).


Japon , Sakurajima :

Le JMA a signalé que du 2 au 9 novembre, l’incandescence du cratère Minamidake (sur le volcan Sakurajima dans la caldeira Aira  ) était visible tous les soirs. Deux explosions au cours des 1er et 2 novembre ont produit des panaches de cendres qui ont atteint 1,8 km au-dessus du bord du cratère. Une explosion a été enregistrée à 15 h 04 le 7 novembre mais les conditions météorologiques en ont empêché la conformation visuelle. Le taux d’émission quotidien de dioxyde de soufre était élevé à 2 200 tonnes par jour le 9 novembre. Le niveau d’alerte est resté à 3 (sur une échelle de 5 niveaux).


La caldera Aira dans la moitié Nord de la baie de Kagoshima contient le volcan Sakurajima, l’un des plus actifs au Japon, après la caldera. L’éruption du volumineux flux pyroclastique d’Ito a accompagné la formation de la caldera de 17 x 23 km il y a environ 22 000 ans. La caldera plus petite de Wakamiko a été formée au début de l’Holocène dans le coin Nord-Est de la caldera d’Aira, avec plusieurs cônes post-caldera. La construction du Sakurajima a commencé il y a environ 13 000 ans sur le rebord Sud de la caldeira d’Aira et a construit une île qui a finalement été reliée à la péninsule d’Osumi lors de la grande éruption explosive et effusive de 1914. L’activité au sommet du cône de Kitadake s’est terminée il y a environ 4850 ans après quoi des éruptions ont eu lieu depuis le Minamidake. De fréquentes éruptions historiques, enregistrées depuis le VIIIe siècle, ont déposé des cendres sur Kagoshima, l’une des plus grandes villes de Kyushu, située dans la baie de Kagoshima, à seulement 8 km du sommet. La plus grande éruption historique a eu lieu entre 1471 et 1476.

Source: Agence météorologique japonaise (JMA) , GVP.

Photo : 8nov19 , @volcanohull / public domain / Volcanodiscovery


Costa Rica , Turrialba / Poas / Rincon de la Vieja / Irazu :

Bulletin hebdomadaire , 9 novembre 2020 .

Volcan Turrialba
Lat: 10,025 ° N; Long: 83,767 ° O;
Hauteur: 3340 m.s.n.m.
Niveau d’activité actuel: 2 (volcan actif)
Dangers potentiellement associés: gaz, émission de cendres, projections balistiques proximales.

Aucune émission de cendres n’a été observée. L’activité sismique reste élevée avec des évènements de type LP et de courts tremors. Les observations géodésiques continuent de détecter une contraction horizontale du massif   Turrialba-Irazú, et elles ont noté une déflation importante ces derniers jours. Les rapports de gaz ou le flux de SO2 n’ont pas pu être mesurés en raison d’une direction du vent défavorable.
Aucune anomalie thermique n’a été détectée par l’analyse MODIS. Le niveau élevé de sismicité est interprété comme une infiltration d’eau de pluie dans le bâtiment, qui, si elle est confirmée, pourrait produire de petites émissions de cendres et des éruptions d’eaux souterraines capables de projections balistiques proximales.

Volcan Poas
Lat: 10,2 ° N; Long: 84,233 ° O;
Hauteur: 2780 m.s.n.m.
Niveau d’activité actuel: 2 (volcan actif)
Dangers potentiellement associés: gaz, éruptions phréatiques, projections balistiques proximales .

Aucune éruption n’a été détectée. L’activité sismique se poursuit avec des tremors de fond plus permanents et d’une amplitude variable. L’inflation observée par la surveillance géodésique depuis août a diminué, maintenant elle n’est plus significative. Le rapport H2S / SO2 reste élevé et le rapport SO2 / CO2 reste faible. Ces mesures sont cohérentes avec l’observation du soufre élémentaire flottant dans le lac au cours de la semaine. Le flux de SO2 n’a pas pu être mesuré en raison d’une direction du vent défavorable. Le niveau du lac a augmenté de 1,4 m en une semaine en raison de fortes précipitations (~ 450 mm sous l’influence de l’ouragan Eta). Le taux d’évaporation / d’infiltration a diminué. Aucune anomalie thermique n’a été détectée par l’analyse MODIS.

Volcan Rincon de la Vieja
Lat: 10,83 ° N; Long: 85,324 ° O;
Hauteur: 1895 m.s.n.m.
Niveau d’activité actuel: 3 (volcan en éruption)
Dangers potentiellement associés: gaz, éruptions phréatiques, projections balistiques proximales, lahars.

L’activité sismique est faible. Les éruptions sont plus sporadiques mais avec une plus grande amplitude. La surveillance géodésique montre un rétrécissement important du sommet du volcan.
Aucune anomalie thermique n’a été détectée par l’analyse MODIS.

À 05:40:00 heure locale le 11 novembre 2020, une éruption a été enregistrée sur le volcan Rincon de la Vieja, avec une colonne qui s’est élevée à 1000 mètres au-dessus de la hauteur du cratère et à 2916 mètres au-dessus du niveau de la mer.  (9564,48 ft).
Durée de l’activité: 5 minutes.

Volcan Irazu
Lat: 9,979 ° N; Long: 83,852 ° O;
Altitude: 3432 m.s.n.m.
Niveau d’activité actuel: 1 (actif)
Dangers potentiellement associés: glissements de terrain.

La surveillance sismique a détecté un glissement de terrain important le 4 novembre avec une crue de type lahar (ruissellement de boue). Le glissement de terrain principal dans le secteur Ouest du volcan a présenté une accélération verticale pendant le week-end, sans être associée à une accélération sur les composantes horizontales. L’analyse par satellite MODIS a détecté une petite anomalie thermique le 4 novembre.

Source : Ovsicori .


Chili , Laguna del Maule :

Le SERNAGEOMIN a rapporté que 10 tremblements de terre volcano-tectoniques de faible magnitude ont été détectés dans le complexe volcanique de Laguna del Maule du 16 au 31 octobre; la sismicité était faible dans la région où un essaim s’était produit en juin. Les données satellitaires n’ont montré aucune déformation, changement de surface, émission de gaz ou anomalie thermique. Le 6 novembre, le niveau d’alerte a été abaissé au vert, le niveau le plus bas sur une échelle à quatre couleurs. L’ONEMI a annulé l’alerte jaune pour San Clemente, mais a déclaré une «alerte précoce préventive» assurant une surveillance continue de la zone et une coordination au sein du système de protection civile.

– 10 événements sismiques classés comme de type volcano-tectonique (VT) ont été enregistrés, associés à des processus de fracture de matériaux rigides dans des systèmes volcaniques. Aucun événement ne présentait un niveau d’énergie permettant de le localiser.
– Les images fournies par la caméra IP installée à proximité du complexe, n’ont pas enregistré d’activité de surface associée au système volcanique.
– Grâce à l’analyse des images satellites Sentinel L2 A et Planet Scope, aucune variation superficielle ou morphologique n’est observée. Il n’y a pas non plus de variations de température ou de radiances associées aux anomalies thermiques, selon le traitement d’image LandSat 8 OLI TIIRS et Sentinel L2 A.

– Aucune anomalie n’a été signalée dans les émissions de dioxyde de soufre (SO2) dans l’atmosphère dans le secteur proche du complexe volcanique, selon les données publiées par le Tropospheric Monitoring Instrument (TROPOMI) et l’Ozone Monitoring Instrument (OMI) Sulfur Dioxide Group (http: //
– Au cours de la période, aucune alerte thermique n’a été enregistrée dans la zone associée au complexe volcanique, selon les données traitées par Middle Infrared Observation of Volcanic Activity (MIROVA)  et par la surveillance thermique temporelle des points chauds globaux (MODVOLC) (
– Les données pour l’évaluation géodésique du complexe volcanique n’étaient pas disponibles en raison de problèmes à l’origine. Les données interférométriques permettent de détecter un comportement similaire à celui observé historiquement dans la zone, sans preuve de changements notables dans le comportement du complexe.

Malgré l’enregistrement d’une activité sismique de faible énergie dans la zone où les essaims sismiques se sont produits en juin de cette année, aucun nouvel épisode de récurrence sismique élevée n’a été observé dans le secteur. Ce qui précède, accompagné de l’analyse d’images satellites, où aucune variation ou anomalie superficielle n’est observée  , suggèrent une stabilité dans le complexe volcanique.

Ce qui précède permet de changer le niveau d’alerte volcanique en:
ALERTE TECHNIQUE VERTE: Volcan actif au comportement stable – Aucun risque immédiat.

Source : GVP , Sernageomin .

Photo : Oscar González-Ferrán (University of Chile)

October 09 , 2018. EN. La Réunion : Piton de la Fournaise , Andaman and Nicobar : Barren Island , Costa Rica : Poas , Chile : Osorno .

October 09 ,  2018.



La Réunion , Piton de la Fournaise :

Activity Bulletin from Monday, October 8, 2018 at 16:00 (local time).

The eruption started on September 15th at 4:25 am local time continues. The intensity of the volcanic tremor (indicator of the eruptive intensity at the surface), after having increased markedly since October 3 at 22h local time (18h UTC) – due to a gradual closure of the entire feeding system, going from the dike (« feeding duct » of the eruption) to the eruptive cone, favoring a phenomenon of « resonance » more important) – has been gradually decreasing for three days (Figure 1).
Piston gases (« gas flushes » or « tremor puffs ») at the eruptive site are always recorded by the OVPF seismometers.

Figure 1: Evolution of RSAM (indicator of volcanic tremor and intensity of eruption) between 04:00 (00h UTC) September 15 and 16:00 (12:00 UTC) October 8 on FOR seismic station, located near the crater Chateau Fort (2000 m altitude on the southeast flank of the terminal cone). (© OVPF / IPGP)

– No volcano-tectonic earthquake was recorded during the day of 7 October or during the current day.
– An inflation (swelling) of the building, witnessing the influence of a source of pressure at the foot of the volcano, is still perceptible. This inflation is accompanied by an increase in the concentrations of CO2 in the soil in the area of ​​the Volcano Cottage.
– The OVPF NOVAC network stations located around the Enclos  still record SO2 flows. Even though their concentrations are 5 times lower than at the beginning of eruption, these flows confirm that there is still magma present at low pressure.
– Observations made today from the Piton de Bert and from the air by OVPF teams have made it possible to locate the flow front. Since September 30, the northern front has progressed 1.8 km and was this morning (8:00 am local time) 500m of the great slopes, the southern and central fronts have not moved. The north  front was this morning less than 120 m from the southern wall of Enclos Fouqué. Detailed mapping was also possible by the OI2 service (Clermont Auvergne University, Figure 2).

Figure 2: Contour mapping of the lava flows between 30/09/2018 (in red) and 08/10/2018 (in blue) deduced from InSAR coherence images. (© LMV / OPGC-OVPF / IPGP)

The surface activity at the level of the eruptive vent is always very limited.
No projection was visible between 10 and 12:30 (local time) but only emissions of gas and steam, sometimes accompanied by detonations. A lava lake is always present inside the cone (Figure 3).
Nevertheless, the activity continues in lava tunnels, with degassing particularly visible along their path, from the eruptive vent to the casting front (Figures 3 and 4). This morning (between 10am and 12:30 local time), a resurgence fed an active channel on all the last third of the northern branch thus favoring its progression towards the East.
– The surface flow rates could not be estimated today because of lava flows that are too weak at the surface.

Figure 3: Shooting of the eruptive site on 08/10/2018 around 08h00 local time. (© OVPF / IPGP)


Figure 4: Thermal imaging of the eruptive site and the lava field taken from Piton Bert on 08/10/2018 around 10h50 local time. (© OVPF / IPGP)

Balance sheet:
Since October 3rd, the OVPF has been recording signals of two trends occurring at different levels:
1) at the level of the eruptive vent: records of « piston gas »; and weak surface activity, most of the activity taking place in lava tunnels with a resurgence this morning feeding an active channel on the last third of the north face of the flow;
2) at the level of the superficial reservoir: pressurization of a localized source under the summit craters at a depth of 1-1.5 km (detected by the inflation of the building) witnessing a refilling of the superficial reservoir by deeper magma (increased CO2 concentrations in the soil outside the Enclos).
Given these two observables, no assumption is excluded as to the continuation of this eruption in the coming days (shutdown, re-intensification of activity on the same site, opening of new cracks, especially further downstream).

Source : OVPF ,


Andaman and Nicobar , Barren Island : 

India’s Only Active Volcano Erupts Again, Experts Link It To Indonesian Earthquake

India’s only active volcano Barren Island has begun spewing lava and ash again, Times of India has reported. Geologists believe that fresh volcanic activity is linked to the recent earthquake in Indonesia.
On 25 September, Indonesian Island of Sulawesi was hit by an earthquake of magnitude 7.5. According to officials of Geological Survey of India (GSI), the volcanic eruption was first detected on 25 September.

“There have been many cases of volcanic eruptions which were preceded by earthquakes of mild intensity. They could be linked, and the source of the trigger may be the same, as the location of Sulawesi earthquake is not very far away,” Director PSS, GSI (North East), Tapan Pal told Times of India. Further, he added that the two events could also be two separate events.
The entire region tectonically active as the Indian plate is sub-ducting below the Burma plate and Indonesian Plate is sub-ducting below the Australian plate. Oceanic crusts melt and comes to the surface as a volcano due to subduction. The previous volcano recorded near Barren Island was during February 2016.

“The volcanic eruption was first evidenced on September 25 and the satellite images confirmed the spewing of lava or pyroclastic material and ash on the north flank of the island,” TOI reported, quoting the Geological Survey of India (GSI) officials as saying.
“Although, there have been many instances of volcanic eruptions which were preceded by mild intensity earthquakes. The GSI, say that it is just be a coincidence and the two may be separate and simultaneous events and the source may be different. “Only a detailed study will ascertain the cause of the eruption,” Tapan Pal, director, PSS, GSI, northeast region said.

The Indian National Centre for Ocean Information Services (INCOIS), Hyderabad, a government agency that monitors earthquakes and releases bulletins, have recorded magnitude between 4.3 and 4.9 in the Indonesian region of Southeast Asia in the days preceding the volcanic eruption from the Barren Island.
“The entire zone is tectonically quite active. As a matter of fact, Indian plate is subducting below Burma plate and the Indonesian plate is subducting under the Australian plate. The oceanic crust melt and migrates upwards until it erupts when the subduction is continuous,” Pal further explained, as for a possible cause of the eruption recorded in September end.
The last recorded volcanic eruption on Barren Island was in February 2016. The GSI official said the 2005 eruption occurred almost a year after the 2004 tsunami that was triggered by an earthquake in Indonesia.
As per an Indian Space Research Organsiation (ISRO) study, scientists have concluded the volcanic spewing that occurred in 2017 was a continuation of the eruption that took place in 2005. Scientists used satellite data to understand the changes in the volcanic region in terms of shape, area and path of lava flows between the years 2005 and 2017.

Source :, The Financial Express.

Photos : Vinay Dixit via Sherine France.


Costa Rica : Poas :

Irregular activity resulted in the closure of Poás Park, visitors were temporarily evacuated.

The administration of Poás Volcano National Park made the decision to close access to tourists for several hours Monday morning, due to increased activity in the crater of the volcano.
Gino Gonzalez, expert of Volcanes Sin Fronteras, told DIARIO EXTRA that the instruments placed on the point of view had detected irregularities and that the park rangers had warned, but from 10 o’clock. it was open again.
« There was an increase in the concentration of volcanic gases that was detected by the instruments in the surveillance zone and the rangers closed momentarily, » he said.

As a precaution, we evacuated the visitors who were in the area at the time and temporarily closed the park.
« We must continue to monitor the seismic signal and see, with the park rangers, if there is an increase in degassing, but there is a slight change in the activity of the volcano compared to a few days ago » said González.
In April 2017, the magmatic eruptions of Poas were probably one of the reasons for the degassing.
« This is part of the activity of a volcano that has recently erupted, we must continue to monitor the volcanic system, » concluded the volcanologist.
The Poás volcano will continue to receive tourists normally, while remaining under surveillance.

Source :

Photo : Natalia Paniagua / Volcanes Sin Fronteras.


Chile, Osorno :

During this period, 56 seismic events were recorded, of which 45 were classified as long period type (LP) events in relation to fluid dynamics within the volcano and / or glacial dynamics. The larger magnitude event had reduced displacement values ​​(DRC) of 16.8 cm2. In addition, it has been classified 10 volcano_tectonic (VT) type events, associated with the fracturing of rigid materials. The larger energy event had a local magnitude (ML) equal to M 1.9 and was located 1.7 km north – northwest of the crater at a depth of 4.2 km.

Surveillance camera images did not show any superficial activity when weather conditions allowed observation.

The indications of the electronic inclinometers did not reveal any changes in relation to changes in the internal dynamics of the volcano.

No emissions of sulfur dioxide (SO2) to the atmosphere in the volcano area have been reported, according to data published by the Ozone Monitoring Instrument (OMI) Sulfur Dioxide Group (http: / / and the National Satellite Environment and Information Data (NESDIS) (http: // satepsanoine ..

No thermal warnings have been reported in the volcano-associated area, according to data processed by Infrared, a means of observing volcanic activity (Mirova) ( and MODVOLC (http : //

Although the seismicity is maintained in similar values ​​compared to the previous fortnight, we note the occurrence of processes which could according to their type cause the instability of the volcanic system, taking into account some episodes occurred sporadically during the previous months, with local magnitudes (ML) greater than M 3.0.

For the above, the volcanic alert is maintained at the level:
YELLOW LEVEL: Changes in the behavior of volcanic activity – Probable time for an eruption: WEEKS / MONTH.

Source : Sernageomin.

Photo :