Iliamna Volcano

Alaska - Mainland


SUMMARY:

Type: stratovolcano
Activity: dormant
Last Eruption: Holocene activity
Rock Type: basaltic andesite to andesite
Eruptive Volume: ? cu km
Location Map from Xerox PARC
Latitude: 60.03 N
Longitude: 153.17 W


Geologic Background:

Iliamna is located on the west side of Cook Inlet. Iliamna is a deeply dissected stratovolcano 225 km SW of Anchorage in the Aleutian Range. The volcano is mostly covered with perennial snowfields and valley glaciers. A prominent fumarole field near the summit produces steam plumes that are commonly visible from Anchorage and the Kenai Peninsula on clear days.

Historic Activity:

  • At least 11 eruptions have been reported since 1768 but historic activity other than steam emissions has not been documented. Large steam plume in 1987, but no ash.

Recent Activity:

  • Two large fumarolic areas occur on the south and east sides of the ice-capped summit. These sulfur-rich fumaroles are inaccessible; under favorable meteorological conditions, the plumes from these fumaroles extend 700 m or more above the summit. 

Data Sources:

  • Global Volcanism Network (V. 21, No. 8 to V. 22, No. 9)

ADDITIONAL INFORMATION


Last Update: 12/27/00