An increase in seismicity has been observed at Iliamna volcano beginning at about 12:00 pm AKDT June 5, 2023 (20:00 UTC). The rate of earthquakes initially occurred in 1 minute intervals and have been becoming more closely spaced. There is a possibility that the earthquakes may be related to magmatic movement or hydrothermal fluids beneath the volcano. However, similar activity has been observed before large mass movements or avalanches at Iliamna volcano, and AVO cannot rule out either possibility at this time.
Due to the seismicity at Iliamna being above background levels the Aviation Color Code and Volcano Alert level for Iliamna are being raised to YELLOW and ADVISORY.
Iliamna volcano is located on the western side of lower Cook Inlet in the Lake Clark National Park. Iliamna is a snow-covered stratovolcano which rises 10,020 feet above sea level. Although steam plumes occur on its eastern flanks, there has been no historic volcanic activity at Iliamna. Iliamna is located 225 km (140 miles) southwest of Anchorage and 113 km (70 miles) southwest of Homer.
Aaron Wech, Acting Scientist-in-Charge, USGS awech@usgs.gov (907) 786-7497
David Fee, Coordinating Scientist, UAFGI dfee1@alaska.edu (907) 378-5460
A new VAN will be issued if conditions change significantly or alert levels are modified. While a VAN is in effect, regularly scheduled updates are posted at
http://www.avo.alaska.edu
The Alaska Volcano Observatory is a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys.
| (1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA) | |
| (2) Issued: | (20230606/0053Z) |
| (3) Volcano: | Iliamna (VNUM #313020) |
| (4) Current Color Code: | YELLOW |
| (5) Previous Color Code: | GREEN |
| (6) Source: | Alaska Volcano Observatory |
| (7) Notice Number: | 2023/A815 |
| (8) Volcano Location: | N 60 deg 1 min W 153 deg 5 min |
| (9) Area: | Cook Inlet-South Central |
| (10) Summit Elevation: | 10016 ft (3053 m) |
| (11) Volcanic Activity Summary: |
An increase in seismicity has been observed at Iliamna volcano beginning at about 12:00 pm AKDT June 5, 2023 (20:00 UTC). The rate of earthquakes initially occurred in 1 minute intervals and have been becoming more closely spaced. There is a possibility that the earthquakes may be related to magmatic movement or hydrothermal fluids beneath the volcano. However, similar activity has been observed before large mass movements or avalanches at Iliamna volcano, and AVO cannot rule out either possibility at this time. Due to the seismicity at Iliamna being above background levels the Aviation Color Code and Volcano Alert level for Iliamna are being raised to YELLOW and ADVISORY. |
| (12) Volcanic cloud height: | NA |
| (13) Other volcanic cloud information: | Unknown |
| (14) Remarks: | Iliamna volcano is located on the western side of lower Cook Inlet in the Lake Clark National Park. Iliamna is a snow-covered stratovolcano which rises 10,020 feet above sea level. Although steam plumes occur on its eastern flanks, there has been no historic volcanic activity at Iliamna. Iliamna is located 225 km (140 miles) southwest of Anchorage and 113 km (70 miles) southwest of Homer. |
| (15) Contacts: | Aaron Wech, Acting Scientist-in-Charge, USGS awech@usgs.gov (907) 786-7497 David Fee, Coordinating Scientist, UAFGI dfee1@alaska.edu (907) 378-5460 |
| (16) Next Notice: | A new VAN will be issued if conditions change significantly or alert levels are modified. While a VAN is in effect, regularly scheduled updates are posted at |