Report on Sangay (Ecuador) — 21 December-27 December 2022
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 21 December-27 December 2022
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2022. Report on Sangay (Ecuador) (Sennert, S, ed.). Weekly Volcanic Activity Report, 21 December-27 December 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 a high level of activity at Sangay during 20-27 December, which included daily explosions, volcanic tremor, and gas, steam, and ash emissions. The daily count of explosions ranged from 708-1,250, though seismic data transmission was sometimes interrupted. Almost daily ash-and-gas plumes were identified in IG webcam images and satellite images according to the Washington VAAC; weather clouds sometimes prevented observations of the summit. Gas, steam, and ash plumes rose as high as 1.2 km above the volcano and drifted mainly NW, W, SW, and S. Multiple daily thermal anomalies were identified in satellite images. Crater incandescence was visible some nights and early mornings. Incandescent material was observed rolling down the SE flank during 26-27 December.
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.