Report on Cleveland (United States) — September 2006
Bulletin of the Global Volcanism Network, vol. 31, no. 9 (September 2006)
Managing Editor: Richard Wunderman.
Cleveland (United States) Short duration explosions during August-October 2006
Please cite this report as:
Global Volcanism Program, 2006. Report on Cleveland (United States) (Wunderman, R., ed.). Bulletin of the Global Volcanism Network, 31:9. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN200609-311240.
52.825°N, 169.944°W; summit elev. 1730 m
All times are local (unless otherwise noted)
Cleveland's commonly observed activity consisting of short duration explosions, such as those seen earlier in the year on 6 February 2006 (BGVN 31:01) and on 23 May 2006 (BGVN 31:07), continued during August and October 2006. This report will cover the 24 August and 28 October eruptions.
At 1955 on 24 August a brief eruption was seen by mariners on a passing ship. The eruption was unconfirmed by satellite data. Video footage sent to the Alaska Volcano Observatory (AVO) on 28 August showed that an ash cloud rose to an approximate altitude of 3 km and produced minor ashfall. Shortly after the eruption, minor steaming was observed from the vent on additional footage. In response to the eruption, the AVO raised the level of Concern Color Code from 'unassigned' to 'Yellow' on 7 September. A weak thermal anomaly in the summit crater was present in subsequent satellite images.
Clouds obstructed visibility through most of September and October.
A pilot reported that a minor eruption started at 1345 on 28 October. Satellite data confirmed the presence of an ash cloud drifting ENE of the volcano. The height of the cloud was estimated at an altitude of 6 km using the satellite imagery. One pilot reported the plume top at an altitude of 9 km. The AVO raised the alert level to 'Orange' during 28-29 October. On 30 October the AVO lowered the level to 'Yellow' because of no further evidence of activity.
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 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.
Information Contacts: Alaska Volcano Observatory (AVO), a cooperative program of the U.S. Geological Survey, 4200 University Drive, Anchorage, AK 99508-4667, USA; Geophysical Institute, University of Alaska, PO Box 757320, Fairbanks, AK 99775-7320, USA; and Alaska Division of Geological & Geophysical Surveys, 794 University Ave., Suite 200, Fairbanks, AK 99709, USA (URL: http://www.avo.alaska.edu/).