Report on Sangay (Ecuador) — 10 August-16 August 2022
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
10 August-16 August 2022
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2022. Report on Sangay (Ecuador). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 10 August-16 August 2022. Smithsonian Institution and US Geological Survey.
2.005°S, 78.341°W; summit elev. 5286 m
All times are local (unless otherwise noted)
IG reported that a notable increase in seismicity at Sangay began at around 1000 on 12 August and was followed by the effusion of a lava flow that descended more than 1 km on the SE flank. Strombolian activity was visible at the summit. Ash plumes rose as high as 3.5 km above the summit and drifted 500 km W and SW, past the coastline, and caused daily ashfall in the provinces of Chimborazo and Guayas during 12-16 August. The Guayaquil International Airport canceled several commercial flights on 13 August due to the presence of ash in the atmosphere. Seismicity decreased to previous levels by 16 August.
Geological Summary. The isolated Sangay volcano, located east of the Andean crest, is the southernmost of Ecuador's volcanoes and its most active. The steep-sided, glacier-covered, dominantly andesitic volcano grew within the open calderas of two previous edifices which were destroyed by collapse to the east, producing large debris avalanches that reached the Amazonian lowlands. The modern edifice dates back to at least 14,000 years ago. It towers above the tropical jungle on the east side; on the other sides flat plains of ash have been eroded by heavy rains into steep-walled canyons up to 600 m deep. The earliest report of an eruption was in 1628. Almost continuous eruptions were reported from 1728 until 1916, and again from 1934 to the present. The almost constant activity has caused frequent changes to the morphology of the summit crater complex.