Report on Reventador (Ecuador) — 17 July-23 July 2013
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 17 July-23 July 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, 17 July-23 July 2013. Smithsonian Institution and US Geological Survey.
0.077°S, 77.656°W; summit elev. 3562 m
All times are local (unless otherwise noted)
IG reported that during 17-19 July seismic activity at Reventador remained high; at times periods of increased seismicity were followed by relatively quiet episodes. The seismic network recorded long-period signals, rockfalls, explosions, and emissions. Based on reports from observers at camp San Rafael, cloud cover often prevented visual observations, although on 18 July a new lava flow on the E flank was observed with a video camera, and a gas-and-ash plume was observed rising 1 km. During 21-22 July gas plumes with low ash content rose to low heights.
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.