The Alaska Volcano Observatory raised its volcano alert level for Mount Spurr on Wednesday. According to a press release, the level was raised from normal to advisory because of an increase in seismic activity and ground deformation that’s been ongoing since the spring. The observatory says there are no indications that an eruption is imminent.
The largest of the recent earthquakes in the region was a magnitude 2.3 recorded last week. The press release says the current increase in earthquake activity around Mount Spurr is similar to past episodes of seismic activity which resulted in eruptions and the partial melting of an ice cap. But the observatory says this type of seismicity will often decrease without producing an eruption.
The statement adds that increased seismic activity on Mount Spurr has resulted in the development of a small lake in the summit crater. The last time a crater lake formed in the volcano’s summit was during seismic unrest that did not lead to an eruption.
The Alaska Volcano Observatory says it will closely monitor Mount Spurr for signals of an impending eruption. According to the press release, it's likely that an eruption would be preceded by further signals that would allow for an advanced eruption warning.
For more information on Mount Spurr’s advisory, visit the Alaska Volcano Observatory's website.