OREGON STATE UNIVERSITY

Okmok

Latitude (dd): 
53.43
Longitude (dd): 
-168.13
Elevation (m): 
1073
Country: 
United States
State (Province, etc): 
Aleutian Islands
Type: 
Shield

 

 

Last updated: May 7, 1997

May 2, 1997
The eruption at Okmok continues. Satellite images confirm the presence of hot lava flows within the caldera and thin, low-level, ash plumes. U.S. Geological Survey volcanologists believe the eruption may continue for a period of weeks to months.

April 4, 1997
The eruption continues at a relatively low level of activity. Satellite images indicate the presence of hot lava flows in the caldera. Occasional thin, low-level plumes are also seen on the satellite images. The plumes have also been reported by nearby aircraft.

March 28, 1997
The Alaska Volcano Observatory reported that observations on March 27 indicated a much decreased level of activity. Recent satellite images showed hot spots in the caldera and occasional thin, low-level plumes.

This info was summarized from the AVO weekly report.

March 21, 1997

Lava continues to flow from a cone in the south side of the caldera. Lava, steam and ash are frequently thrown from the caldera. Plumes often reached heights of 16,000 ft (5000 m) above sea level and stretched for 150 miles (240 km) over the past week. On March 19, one plume reached 28,000 ft (8500 m) above sea level.

This info was summarized from the AVO weekly report.

February 18, 1997

An ash plume was seen reaching heights of 10,000-15,000 ft (3000-4500 m) above sea level over Okmok and stretched to the southwest. During the night, a bright red glow was reflected from the clouds above the hot spot on Okmok.

February 13, 1997:

A small eruption began at Okmok, Alaska on the morning of February 13. An ash plume was seen rising from a cone inside the caldera at about 10:00 am. This cone is about 2500 ft (760 m) high. The plume stretched to heights of about 5,000 ft (1525 m) above sea level and was blown to the southwest.

Okmok volcano is found on Umnak Island in the eastern Aleutian Islands. It is a six mile (10 km) wide caldera. It has had several eruptions in historic times. These eruptions are normally accompanied by ash plumes as high as 30,000 ft (9150 m), but the plumes are usually much smaller. Lava flows from 1945 and 1958 can be found on the caldera floor. The last erupion of Okmok began in November of 1986 and lasted until February of 1988.

The nearest settlements to Okmok consist of about 35 people in Nikolski, 45 miles (72 km) west of the volcano and a few people at the abandoned Fort Glenn military base, 10 miles (16 km) east of the volcano.


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