Report on Reventador (Ecuador) — 4 April-10 April 2007
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 4 April-10 April 2007
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2007. Report on Reventador (Ecuador). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 4 April-10 April 2007. Smithsonian Institution and US Geological Survey.
0.077°S, 77.656°W; summit elev. 3562 m
All times are local (unless otherwise noted)
Incandescent blocks ejected from the summit of Reventador that subsequently rolled down the S flanks were observed at night during 3-4 April. Satellite imagery revealed ash plumes drifting W and a large thermal anomaly over the crater. On 4 April, a plume rose to an altitude of 4.6 km (15,100 ft) a.s.l. Crater incandescence was observed on 4 and 6 April and "cannon shots" were heard on 6 April. Ash-and-steam emissions were observed during 8-9 April. Steam emissions from the flanks on 8 April possibly originated from a lava flow.
Geologic Background. 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.