Nearly 300,000 Americans remain on alert as Mount Spurr continues to show signs of volcanic unrest that began earlier this year.
While seismic activity is still elevated, the Alaska Volcano Observatory (AVO) said Thursday that it detected 60 to 80 earthquakes per week under Mount Spurr in the last month, a rate lower than in January and February.
‘The rate of deep earthquakes—occurring more than 6 miles below sea level—has remained relatively steady, indicating that magma is still active deep beneath the volcano,’ the AVO reported.
Ground deformation, a sign of magma movement, has slowed over the past three weeks. Volcanic gas measurements have not been possible since March due to persistent poor weather that has prevented monitoring flights.
‘The modest changes in monitoring data over the past month suggest the likelihood of an eruption has decreased,’ AVO noted, adding that the lack of recent gas measurements has made it more difficult to fully assess the volcano’s current state.
Despite the decline in surface activity, AVO emphasized that an eruption remains a possibility due to continued deep magma movement.
While Anchorage lies outside the immediate impact zone of Mount Spurr, previous eruptions in 1953 and 1992 sent ash clouds over the city, coating it in about a quarter inch of ash.
A similar event today could result in widespread ashfall across the region, the AVO warned.
This is a developing story… More updates to come
While Anchorage lies outside the immediate impact zone of Mount Spurr, previous eruptions in 1953 and 1992 (pictured) sent ash clouds over the city, coating it in roughly a quarter inch of volcanic ash
Mount Spurr began exhibited three key signs of a forthcoming eruption earlier this year: increased seismic activity, swelling of the volcano’s surface and snow and ice melt near the summit due.
While ground deformation has dramatically slowed, AVO highlighted that it happened in Fall 2024 before picking up again.
‘Collapse of snow and ice into the summit crater lake that formed during this period of unrest continues, along with steam emissions from fumaroles within and around the summit crater,’ Thursday’s update reads.
‘There have been no significant changes to the fumaroles within Crater Peak over the past month.’
Fluctuation rates of earthquakes has also occurred during past unrest periods, for example before the eruption of Redoubt Volcano in 2009.
The volcano, located on on the west side of Cook Inlet, saw seismic activity dip in September 2008, but pick back up just three days before it erupted on March 23, 2009.
‘We cannot assign an exact timeframe for when an eruption will occur, if it does,’ the AVO said.
‘We expect to see additional changes to monitoring data prior to an eruption, as magma moves closer to the surface.’
