The level of seismic activity has changed little over the past week and remains above background levels. The ongoing seismic activity is characterized by low-level seismic tremor, small discrete events, and very small explosions. No activity was observed in mostly cloudy satellite images this week.
Shishaldin volcano, located near the center of Unimak Island in the eastern Aleutian Islands, is a spectacular symmetric cone with a base diameter of approximately 16 km (10 mi). A 200-m-wide (660 ft) funnel-shaped summit crater typically emits a steam plume and occasional small amounts of ash. Shishaldin is one of the most active volcanoes in the Aleutian volcanic arc, with at least 54 episodes of unrest including over 24 confirmed eruptions since 1775. Most eruptions are relatively small, although the April-May 1999 event generated an ash column that reached 45,000 ft above sea level.
February 21, 2016. Shishaldin, Alaska :
54°45’19” N 163°58’16” W,
Summit Elevation 9373 ft (2857 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW
Source : AVO
Photo : Read, Cyrus ( 2008)