Report on Cleveland (United States) — 6 July-12 July 2005
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 6 July-12 July 2005
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2005. Report on Cleveland (United States). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 6 July-12 July 2005. Smithsonian Institution and US Geological Survey.
52.825°N, 169.944°W; summit elev. 1730 m
All times are local (unless otherwise noted)
Satellite imagery of Cleveland taken during 1-8 July revealed increased activity at the volcano, so AVO assigned a Concern Color Code of Yellow on 7 July. The images showed increased heat flow, thin ash deposits, and possible debris flows extending ~1 km down the volcano's flanks from the summit crater. AVO reported that based on historical eruptions at Cleveland, it is possible that explosive, ash-producing events could occur at any time without warning (due to a lack of seismic monitoring).
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.