|Start:||March 19, 1987 ||Observed|
|Stop:||May 2, 1987 ||Observed|
|Fumarolic or hydrothermal activity: ||
|Eruption Type:||Not an eruption.|
From Smithsonian Institution (1987): "At 0800 on 19 March Reeve Aleutian Airways pilots Edward Livingston and Dale Schram observed a large steam plume rising about 1100 m above the summit. No ash appeared in the plume. Almost 3 hours later Northern Air Cargo pilot Wallace Niles observed a steam plume rising 1,000 m above the summit from a upper S flank vent. The plume drifted NNW. John Reeder noted that minor steam emissions are nearly continuous from Iliamna but a large steam plume is unusual." This activity does not constitute a volcanic eruption.