“Unrest continues at Mount Spurr. Small, shallow earthquakes beneath the summit continue at a low rate, but with a slight increase over the previous week. The most recent deformation data from stations on Mount Spurr suggest a slowing of the inflation that has been ongoing since March of 2024. It is not known at this time whether this is related to changes in the volcanic system or seasonal changes as winter conditions affect stations. No other activity was observed in clear satellite or webcam images throughout the week. AVO is closely monitoring Mount Spurr for signs of increased unrest using local seismic, infrasound, web camera, and GNSS stations, along with regional infrasound and lightning networks and satellite data. We would expect changes in the earthquakes, ground deformation, summit lake, and fumaroles if magma began to move closer to the surface. Thus, if an eruption were to occur, it would be preceded by additional signals that would allow advance warning,” says a Friday bulletin from the Alaska Volcano Observatory.

“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.” What a cranky mountain.