IG reported that activity at Reventador increased on 25 March. At 1830 an explosion was followed by a pyroclastic flow that traveled 500 m down the flanks. Strombolian activity produced gas-and-ash plumes that rose 1.5 km above the crater. During 26-29 March continuous tremor was interspersed with explosions and long-period earthquakes. Although cloud cover often prevented crater views, video cameras showed a lava flow traveling down the S flank and incandescent material erupting from the crater. Emissions with small amounts of ash rose 1 km on 28 March. Ashfall was reported in Hosteria El Reventador and camp San Rafael on the flanks. A load roar reported at 0300 on 31 March was followed by observations of incandescent material traveling 1 km down the S flank. Cloud cover prevented visual observations the next day.

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 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 left extensive deposits on the scarp slope. 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-EPN)