Lava flow from Etna’s New SE crater this morning seen on the INGV thermal webcam
This morning, the ongoing eruptive activity at the volcano changed: a lava flow started to emerge from a vent on the eastern summit of the New SE crater and quickly descended to its base.
At the same time, the strombolian activity from the New SE crater’s main vent and, less frequently, from the Voragine central crater, decreased a bit (but continue). Both had been quite impressive during the past days, especially the activity at the New SE crater. While fluctuating and at times being intense, it had not intensified to another paroxysm (lava fountaining episode) such as on 13-14, 21 and 22 Dec last month, something that had been more or less expected. Volcanic tremor is currently moderate to high, but not showing significant variations compared to previous days. It might be worth mentioning that 3 quakes of magnitudes above 3 occurred under the volcano yesterday. Some were felt by people in the area. Whether they indicate magma movements and further changes in activity in the near future remains speculation. As usual, Etna, always good for surprises, will tell us the answer!
Strombolian activity from the New SE crater last night (image: INGV webcam)
View of the pyroclastic flow at Semeru volcano this afternoon (image: Pasek Made / facebook)
The volcano had a significant eruptive phase this afternoon. Starting at around 17:24 local time, a pyroclastic flow was observed that traveled a distance of approx. 4500 m, according to Indonesia’s Civil Defense Agency BNPB.
The hot avalanche was likely caused by collapses of parts of the lava dome and/or upper parts of the lava flow on the steep southern slope of the volcano. Associated ash plumes rose to an altitude of 5500 m above sea level. The volcanologists at the observatory registered a corresponding seismic signal with up to 22 mm amplitude that lasted for the considerable long period of 4287 seconds (approx. 1 hour 20 mins).
Merapi (Central Java, Indonesia): The activity of the volcano is on increasing trend. A first true pyroclastic flow descended this morning from the growing lava dome. Early this morning at around 5 am local time, a larger rockfall disintegrated into a turbulent and highly mobile mixture of hot rocks, ash particles, and hot gasses, released from from the breaking lava particles,- a glowing avalanche that traveled approx. 1500 m downhill into the Kali Krasak valley. Ash plumes from rising fine material separating from the flow rose about 500 m. … [read more] … [show less] Such avalanches are known by volcanologists under the terms of nuée ardente, block-and-ash flow, pyroclastic flow or pyroclastic density current, and represent the deadliest volcanic hazard of volcanoes such as Merapi, which is a notorious producer of them during most of its eruptions. While this morning’s flow was still a small one and still stopped relatively far from inhabited areas, the length of such pyroclastic flows can easily reach many kilometers, and larger ones should be expected to occur at any time now.
Semeru (East Java, Indonesia): Explosive activity continues. Volcanic Ash Advisory Center (VAAC) Darwin warned about a volcanic ash plume that rose up to estimated 18000 ft (5500 m) altitude or flight level 180 . The full report is as follows: VA TO FL180 OBS FROM GND AT 16/1024Z OBS VA DTG:16/1132Z to 18000 ft (5500 m)
Popocatépetl (Central Mexico): (16 Jan) Explosive activity continues. Volcanic Ash Advisory Center (VAAC) Washington warned about a volcanic ash plume that rose up to estimated 20000 ft (6100 m) altitude or flight level 200 . The full report is as follows: ONGOING VA EMS. to 20000 ft (6100 m)
Fuego (Guatemala): Explosive activity continues. Volcanic Ash Advisory Center (VAAC) Washington warned about a volcanic ash plume that rose up to estimated 14500 ft (4400 m) altitude or flight level 145 . The full report is as follows: NEW VA EMS. to 14500 ft (4400 m)
Sangay (Ecuador): Volcanic Ash Advisory Center Washington (VAAC) issued the following report: VA EMS HAS DISP
Reventador (Ecuador): Explosive activity continues. Volcanic Ash Advisory Center (VAAC) Washington warned about a volcanic ash plume that rose up to estimated 16000 ft (4900 m) altitude or flight level 160 . The full report is as follows: ONGOING VA EMS. to 16000 ft (4900 m)
Sabancaya (Peru): Volcanic Ash Advisory Center Buenos Aires (VAAC) issued the following report: VA NOT IDENTIFIABLE
Satellite image of Klyuchevskoy volcano on 15 Jan 2021
