USGS Volcano Notice - DOI-USGS-AVO-2026-05-05T20:15:40+00:00

ALASKA VOLCANO OBSERVATORY INFORMATION STATEMENT
U.S. Geological Survey
Tuesday, May 5, 2026, 2:31 PM AKDT (Tuesday, May 5, 2026, 22:31 UTC)

ANIAKCHAK (VNUM #312090)
56°54'21" N 158°12'32" W, Summit Elevation 4400 ft (1341 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

Power has been sufficiently restored to the Port Heiden Receive Facility, allowing stable data flow from Aniakchak seismic stations. There are now enough reliable data to establish the real-time state of the volcano. Due to this, Aniakchak Volcano is moving from UNASSIGNED to GREEN/NORMAL.

Aniakchak Volcano had been at UNASSIGNED since December 23, 2025 due to a lack of data received from Aniakchak seismic stations following a power outage at the Port Heiden Receive Facility. Repairs have since been made to the Port Heiden Receive Facility, sufficiently restoring data flow from the Aniakchak network.

Aniakchak volcano, located in the central portion of the Alaska Peninsula, consists of a stratovolcano edifice with a 6 mile (10 km) diameter summit caldera. The caldera-forming eruption occurred around 3,500 years ago. Post-caldera eruptions have produced lava domes, tuff cones, and larger spatter and scoria cone structures, including Half-Cone and Vent Mountain, all within the caldera. The most recent eruption occurred in 1931 and created a new vent and lava flows on the western caldera floor while spreading ash over much of southwestern Alaska. Aniakchak volcano is 16 miles (26 km) southeast of the nearest community, Port Heiden, and 416 miles (670 km) southwest of Anchorage, Alaska. It is located in Aniakchak National Monument and Preserve.

CONTACT INFORMATION:

Matt Haney, Scientist-in-Charge, USGS mhaney@usgs.gov (907) 786-7497

David Fee, Coordinating Scientist, UAFGI dfee1@alaska.edu (907) 378-5460

Contact AVO: https://avo.alaska.edu/contact

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.