Newest Volcano Notice Including Spurr

ALASKA VOLCANO OBSERVATORY INFORMATION STATEMENT
U.S. Geological Survey
Thursday, April 4, 2024, 4:30 PM AKDT (Friday, April 5, 2024, 00:30 UTC)

SPURR (VNUM #313040)
61°17'56" N 152°15'14" W, Summit Elevation 11070 ft (3374 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

Conditions at Mount Spurr volcano have improved and AVO is receiving data from earthquake monitoring stations and a remote web camera at the volcano 120 km (75 miles) west of Anchorage. Data are now sufficient to establish the state of the volcano. As a result, the Aviation Color Code and Volcano Alert Level are changed to GREEN/NORMAL.

Summary

A thick winter snowpack prevented data transmission from seismic stations on Mount Spurr volcano to AVO in Anchorage.

Conditions on the volcano have improved recently. In addition, following work at the Anchorage receive facility and some remote radio reconfigurations, AVO is reliably acquiring data from six stations of the Spurr Network. As a result, AVO can now track volcanic activity in real time and provide early warning of eruptive activity.

AVO is also acquiring webcam images from station CKT. A field visit is planned for late April to make further improvements prior to a larger effort later in the summer of 2024 to improve network operations for next winter.

Prognosis

As days lengthen and more snowmelt occurs, data transmission will continue to improve and stabilize. A field visit planned for late April 2024 should further establish the network's functionality.

Activity and monitoring at Mount Spurr

Though AVO’s monitoring is now restored, a plausible eruption scenario for Mount Spurr would involve months of elevated earthquake activity before an eruption. At present, Mount Spurr is not showing any signs of unrest.

With the current monitoring network health, AVO is able to provide timely eruption forecasts and quickly confirm or dismiss reports of activity. In addition to seismic monitoring, AVO will use satellite data, regional seismic, infrasound and lightning networks, and reports from pilots and ground observers to detect signs of unrest or eruptive activity.

Mount Spurr volcano is an ice- and snow-covered stratovolcano located on the west side of Cook Inlet approximately 120 km (75 mi) west of Anchorage. The only known historical eruptions occurred in 1953 and 1992 from the Crater Peak flank vent located 3.5 km (2 mi) south of the summit of Mount Spurr. These eruptions were brief, explosive, and produced columns of ash that rose up to 20 km (65,000 ft) above sea level and deposited several mm of ash in south-central Alaska, including approximately 6 mm of ash on Anchorage in 1953. The last known eruption from the summit of Mount Spurr was more than 5,000 years ago. Primary hazards during future eruptions include far-traveled ash clouds, ash fall, pyroclastic flows, and lahars or mudflows that could inundate drainages all sides of the volcano, but primarily on the south and east flanks.

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

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.