Report on Reventador (Ecuador) — 2 June-8 June 2021
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
2 June-8 June 2021
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2021. Report on Reventador (Ecuador). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 2 June-8 June 2021. Smithsonian Institution and US Geological Survey.
0.077°S, 77.656°W; summit elev. 3562 m
All times are local (unless otherwise noted)
IG reported that a high level of activity continued to be recorded at Reventador during 1-8 June; adverse weather conditions sometimes prevented visual confirmation. Seismicity was characterized by 3-23 daily explosions, volcano-tectonic and harmonic tremor events, long-period earthquakes, and signals indicating emissions. Gas, steam, and ash plumes, often observed multiple times a day with the webcam or reported by the Washington VAAC, rose higher than 1 km above the summit crater and drifted mainly W, NW, and NE. Crater incandescence and incandescent blocks rolling as far as 500 m down the S flank were occasionally observed at night. Lava flows on the N, NE, SE, and S flanks were active. The report also noted that a bulging area on the N flank first detected on 13 May had persisted.
Geological Summary. Reventador is the most frequently active of a chain of Ecuadorian volcanoes in the Cordillera Real, well east of the principal volcanic axis. The forested, dominantly andesitic Volcán El Reventador stratovolcano rises to 3562 m above the jungles of the western Amazon basin. A 4-km-wide caldera widely breached to the east was formed by edifice collapse and is partially filled by a young, unvegetated stratovolcano that rises about 1300 m above the caldera floor to a height comparable to the caldera rim. It has been the source of numerous lava flows as well as explosive eruptions that were visible from Quito in historical time. Frequent lahars in this region of heavy rainfall have constructed a debris plain on the eastern floor of the caldera. The largest historical eruption took place in 2002, producing a 17-km-high eruption column, pyroclastic flows that traveled up to 8 km, and lava flows from summit and flank vents.