Report on Cleveland (United States) — 27 April-3 May 2016
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 27 April-3 May 2016
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2016. Report on Cleveland (United States). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 27 April-3 May 2016. Smithsonian Institution and US Geological Survey.
52.825°N, 169.944°W; summit elev. 1730 m
All times are local (unless otherwise noted)
On 29 April, AVO reported that no activity had been detected at Cleveland following the 16 April explosion; seismicity had returned to low levels within an hour of the event and no infrasound (pressure sensor) signals had been detected. Recent satellite images indicated that the August 2015 lava dome was gone and had been replaced with a small cinder cone within the summit crater. The Level of Concern Color Code was lowered to Yellow and the Volcano Alert Level was lowered to Advisory.
Geologic Background. The beautifully symmetrical Mount Cleveland stratovolcano is situated at the western end of the uninhabited, dumbbell-shaped Chuginadak Island. It lies SE across Carlisle Pass strait from Carlisle volcano and NE across Chuginadak Pass strait from Herbert volcano. Joined to the rest of Chuginadak Island by a low isthmus, Cleveland is the highest of the Islands of the Four Mountains group and is one of the most active of the Aleutian Islands. The native name, Chuginadak, refers to the Aleut goddess of fire, who was thought to reside on the volcano. Numerous large lava flows descend the steep-sided flanks. It is possible that some 18th-to-19th century eruptions attributed to Carlisle should be ascribed to Cleveland (Miller et al., 1998). In 1944 Cleveland produced the only known fatality from an Aleutian eruption. Recent eruptions have been characterized by short-lived explosive ash emissions, at times accompanied by lava fountaining and lava flows down the flanks.