After ash emissions stopped yesterday afternoon, the volcano has resumed its activity today. Indeed, on the thermal cam you can see that the area around the saddle vent is hot and glowing tephra is being extracted. Ash is caught by the strong wind, pressed down and transported towards the northeast. The tremor fluctuates strongly at the border to the “red area”. The LGS maintains the pre-warning level “orange”. It already indicated an increase in activity 3 days ago. Under the Valle del Bove the number of weak earthquakes increased slightly again. Earthquake activity below the summit crater is unremarkable.
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.
Sinabung erupted
On the Indonesian island of Sumatra the Sinabung erupted again. The VAAC Darwin published a VONA message, after which volcanic ash rose to a height of 9800 m. The cloud drifted in a westerly direction. In time a second cloud reached a height of 4200 m and was multiplied in eastern direction.
The volcanologists of Magma/VSI registered increased seismic activity the day before. Among the signals was a Tornillo. They detected the eruption in 2 signals with maximum amplitudes of 120 mm and 1785-2246 seconds duration. Although the eruption cloud rose higher than during the last eruption, there must not have been a much higher energy behind it. Weaker winds may have favoured the vertical rise of the volcanic ash to higher altitudes. The seismic signals indicate an eruption similar to the one on 8 August. In fact, the main eruption lasted longer than now.
The seismicity was increased in the first quarter of the day. There were 19 volcano-tectonic tremors recorded. Another Tornillo was also recorded. Tremor also occurred. In fact, it looks like the sinking has entered a new eruptive phase.
Erupsi #Sinabung 10 Agustus 2020 10.16WIB https://t.co/TuGNOVdDhe pic.twitter.com/EcTnTeSzxF
— MAGMA Indonesia (@id_magma) August 10, 2020
Iceland: inflation confirmed
The IMO confirmed the presumed inflation in the earthquake zone near the Fagradalsfjall volcano on the Reykjanes peninsula. The ground elevation has been 3 cm since the beginning of the swarm earthquake on 18 July. The magma inflation was detected by INSAR satellite images. The deformation took place mainly during the main phase of the quake activity between July 18th and 20th. The magma penetrated into a northeast-southwest striking fault zone, which was already discovered in 2017, when swarm quakes also occurred there. The deformation is considered part of a larger volcanic-tectonic reactivation event on the Reykjanes Peninsula. This not only results in ground uplift, but also in subsidence. Such subsidence has now been discovered in the area of the Svartsengi geothermal power plant. It started 2 days before the swarm earthquake at Fagradalsfjall and was probably caused by the underground run-off of magmatic fluids.
Raung with Hotspot
The volcano Raung is located in the east of the Indonesian island of Java and has been under special observation by local volcanologists for several days. Seismic signals signalled the awakening of the volcano. Small ash clouds were also sighted rising above the crater rim. Now there is a further indication of the increasing activity of the volcano: the sentinel satellites detected a heat source. It emits radiation with a power of 33 MW and is located at the northern rim of the small crater that had formed in the caldera in 2015. The crater is part of an intra-caldera cinder cone. The evidence suggests strombolian activity. Visual observations of the crater rim have not been reported to me. Raung is part of the Ijen volcanic massif, which also includes the better known sulfur-producing Kawah Ijen.
Stromboli: Another strong explosion
The Italian volcano Stromboli once again proved its unpredictability tonight and erupted a large amount of tephra at 3 o’clock, which covered the entire summit area with glowing bombs. On the video embedded below you can see that it was a short eruption phase with 4 explosions. At least 2 winding vents were involved in the explosions. Such unusually strong eruptions occurred in the past and cost the lives of several volcano observers. This time, however, no people should have been in the summit area, because the ascent was still blocked. Local residents report that they were woken up by a loud bang. However, no material fell in the lower part of the volcano. The eruption was weaker than on 3 July last year.
Unlike last year’s two eruptions, there was no longer period of increased activity before. On the contrary, the eruptions of the past days were comparatively weak. Only a few hours before, the strombolian eruptions increased significantly. Images of these were shared in our FB group “volcanoes and volcanism“. The only indicator for magma rise was an increased carbon dioxide emission: in the last two days the daily production increased from less than 200 tons to almost 1000 tons. Already at the end of June there were 2 measurements of more than 1000 tons per day.
Raung: Eruption started
On the Indonesian island of Java, the volcano Raung has started an eruption. The eruption was preceded by a seismic crisis. It started on July 13th. The first small ash cloud was detected 2 days ago. A VONA warning was issued and air traffic on the neighbouring island of Bali was suspended. However, due to the corona lockdown, only very few flights may have been affected. In the meantime a stable eruption on a low level has occurred. During the first 6 hours of the day, volcanologists from VSI recorded 28 seismic eruption signals. They had amplitudes between 4 and 14 mm and lasted up to 150 seconds. MIROVA recorded a moderate thermal anomaly with peak values of 15 MW. One can assume strombolian activity, where glowing tephra accumulates in the crater. The alert status has been raised to “yellow.”
The last eruptions of the Raung occurred in 2015, when the eruptions started like now and increased within a few weeks to a very interesting eruption, where not only strombolian eruptions were generated, but also lava flows that filled part of the crater.
Nishinoshima grows
The Japanese volcanic island of Nishinoshima is growing and growing and is not only producing lava flows but also ash clouds. On 13. July these reached an altitude of 6100 m, with a cone height of 200 m.The Japanese coast guard photographed lava fountains that were as high as the cinder cone. Today the activity seems to be decreasing. The VAAC recorded volcanic ash at an altitude of 3700 m.
New observations will be made on July 20 by the meteorological observation ship “Keifu”.
Sangay: Thermal anomalies detected
The Ecuadorian volcano Sangay is still active. Today, explosive eruptions were detected, which caused volcanic ash to rise to an altitude of 6400 m. The ash was drifted westward. In a special report of the IGEPN the morphological changes of the volcano caused by the eruptions were investigated. Most striking is a depression on the southeast flank. It was carved into the flank by lava flows, debris avalanches and pyroclastic flows. The gorge is almost 400 m wide, 4 km long and starts from the crater. Three thermal anomalies have been detected in it. 2 of the anomalies are located in the upper part of the canyon. The top anomaly is in the crater area and marks an explosive vent. The 2nd anomaly is below the base of the crater and represents the source of the lava flows. The 3rd heat source is located in the lower part of the gorge and is probably generated by an accumulation of hot deposits of pyroclastic flows.
Piton de la Fournaise: No eruption upcoming
The seismic crisis started on July 3, 2020 at 07:20 local time and ended around 08:00 local time. This episode was accompanied by surface deformations which remained extremely weak and localized at the top of the Piton de la Fournaise. Since then, no resumption of seismic activity or deformation has been observed.
Several hours without any activity being observed are evidence of the deep stop of magma in the building.
Nevertheless, given the resumption of inflation observed since June 16, a medium-term eruption cannot be ruled out.
Popocatepetl: Volcano with spirit
Close to the Mexican capital the Popocatepetl is still active. Yesterday the CENAPRED Institute published a very atmospheric photo of a sunset eruption. Besides the explosion, 169 ash-steam exhalations and 32 minutes of tremors were recorded. Today, explosive volcanic eruptions were also recorded: the VAAC issued 2 VONA messages according to which volcanic ash had risen to an altitude of 5800 m.
Popocatepetl has become a permanently active volcano in recent years. Only seldom there are longer pauses in eruption. In addition a lava dome grows sporadically in the crater. The ascent is prohibited.