Report on Reventador (Ecuador) — 30 October-5 November 2013
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
30 October-5 November 2013
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2013. Report on Reventador (Ecuador). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 30 October-5 November 2013. Smithsonian Institution and US Geological Survey.
0.077°S, 77.656°W; summit elev. 3562 m
All times are local (unless otherwise noted)
During 30 October through 5 November, IG reported that moderate activity from Reventador continued. Elevated seismicity included explosions (8-35 per day), long period earthquakes, and tremor related to emissions and fluid movement in the crust (harmonic tremor). Plumes of steam were frequently observed when the weather permitted; ash plumes were generated on 31 October, 2 November, and 5 November. Ashfall from these events reached the town of San Rafael on 31 October and 2 November; a pilot observed ash on 2 November at an altitude of 6.7 km (22,000 ft). Observers heard roaring noises and sounds resembling "cannon shots" on 31 October and 1 November.
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.