Report on Reventador (Ecuador) — 14 September-20 September 2005
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
14 September-20 September 2005
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2005. Report on Reventador (Ecuador). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 14 September-20 September 2005. Smithsonian Institution and US Geological Survey.
0.077°S, 77.656°W; summit elev. 3562 m
All times are local (unless otherwise noted)
On 1 and 2 September, lahars traveled down Reventador's flanks. During 5-11 September, there was a substantial decrease in seismicity at Reventador, except for tremor, in comparison to the previous week. Pilots reported ash clouds on 13 and 15 September at a height of ~7 km (23,000 ft) a.s.l. No ash was visible on satellite imagery.
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.