Report on Reventador (Ecuador) — 28 September-4 October 2005
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
28 September-4 October 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, 28 September-4 October 2005. Smithsonian Institution and US Geological Survey.
0.077°S, 77.656°W; summit elev. 3562 m
All times are local (unless otherwise noted)
During 19-25 September, several small explosions occurred at Reventador. An explosion on 20 September produced an ash plume to a height of ~5.8 m (19,000 ft) a.s.l. Small amounts of ash fell in the towns of El Chaco, San Francisco de Borja, and Baeza. During the report week, there was a reduction in the number of earthquakes at the volcano.
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.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)