Report on Reventador (Ecuador) — 22 December-28 December 2021
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
22 December-28 December 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, 22 December-28 December 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 at Reventador during 21-28 December. Gas-and-ash plumes, often observed multiple times a day with the webcam or reported by the Washington VAAC, rose as high as 1.2 km above the summit crater and drifted mainly NW, W, and SW. Crater incandescence was visible nightly, and lava flows were active on the NE and N flanks. Explosions, crater incandescence, and incandescent blocks rolling 500 m down the N and NE flanks were observed at night during 27-28 November.
Geological Summary. Volcán El 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 stratovolcano has 4-km-wide avalanche scarp open to the E formed by edifice collapse. A young, unvegetated, cone rises from the amphitheater floor about 1,300 m to a height comparable to the rim. It has been the source of numerous lava flows as well as explosive eruptions visible from Quito, about 90 km ESE. Frequent lahars in this region of heavy rainfall have constructed a debris plain on the eastern floor of the scarp. The largest recorded 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.