Report on Cleveland (United States) — 1 February-7 February 2006
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 1 February-7 February 2006
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2006. Report on Cleveland (United States). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 1 February-7 February 2006. Smithsonian Institution and US Geological Survey.
52.825°N, 169.944°W; summit elev. 1730 m
All times are local (unless otherwise noted)
An ash cloud emitted from Cleveland was detected on satellite imagery beginning at 0757 on 6 February, leading AVO to increase the Concern Color Code to Red from an unassigned code (Cleveland does not normally have a Concern Color Code because it is not seismically monitored, therefore no definitive information about background activity is available). An image at 0900 on the same day showed a small ash cloud ~130 km ESE of the volcano. Initial data suggested that the cloud was at a height of ~6.7 km (22,000 ft) a.s.l. The ash cloud detached from the volcano and there was no indication of continuous ash emission. Ash had largely dissipated on satellite imagery by 1341. AVO received no information about additional ash emissions, so they decreased the Concern Color Code to Orange around 1655 on 6 February.
Geologic Background. The beautifully symmetrical Mount Cleveland stratovolcano is situated at the western end of the uninhabited 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 it 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.