Report on Reventador (Ecuador) — 20 May-26 May 2015
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 20 May-26 May 2015
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2015. Report on Reventador (Ecuador) (Sennert, S, ed.). Weekly Volcanic Activity Report, 20 May-26 May 2015. Smithsonian Institution and US Geological Survey.
0.077°S, 77.656°W; summit elev. 3562 m
All times are local (unless otherwise noted)
During 20-26 May IG reported moderate-to-high seismic activity including explosions, long-period earthquakes, harmonic tremor, and signals indicating emissions at Reventador; cloud cover sometimes prevented visual observations. A lava flow on the SW flank advanced during 20-21 May. During 24-25 May ash plumes rose 600-800 m and drifted SW, although at 1730 on 25 May a water vapor plume with moderate ash content rose 1.5 km and drifted SW.
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 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 left extensive deposits on the scarp slope. 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.