Report on Sangay (Ecuador) — 12 February-18 February 2020
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 12 February-18 February 2020
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2020. Report on Sangay (Ecuador). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 12 February-18 February 2020. 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 permanent monitoring station located near the base of Sangay was repaired during 26 January-1 February and had begun to again transmit data in real time. The technician reported constant ash emissions during the expedition. A high level of activity persisted at Sangay during 12-18 February, though weather clouds often prevented visual confirmation. Ash, steam, and gas plumes rose 570-870 m above the summit and drifted W and SW according to Washington VAAC advisories. A webcam recorded lava blocks descending the SE flank on 17 February.
Geologic Background. 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 horseshoe-shaped 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 sculpted by heavy rains into steep-walled canyons up to 600 m deep. The earliest report of a historical eruption was in 1628. More or less 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.