Eruptions Possible at Two Alaska Volcanoes

The Federal Aviation Administration has imposed flight restrictions over the 7,073-foot (2,156-metre) volcano located 480 miles (775 km) southwest of Anchorage. No ash had fallen on Monday on the closest community, Perryville, home to 110 people and located 22 miles (35 km) to the south.

"This volcano tends to have a lot of this low-level activity and what it's doing right now is not out of the ordinary, even though it's erupting," said John Eichelberger of the University of Alaska Fairbanks Geophysical Institute and Alaska Volcano Observatory.

But he added: "A large eruption combined with the wind going in action would have a severe effect on Perryville."

Veniaminof is one of the biggest and most active volcanoes in the Aleutian Arc and has erupted 12 times in the past 200 years, according to the observatory. It had minor ash-producing explosions, similar to the current episode, in 2002 and 2004, the observatory said.

The other stirring volcano is Mount Spurr, an 11,070-foot (3,374-metre) peak about 80 miles (130 km) west of Anchorage.

Small earthquakes beneath Spurr began last summer have intensified over the last week or so, Eichelberger said. The activity has included an emission of heat that has created a lake from some of the snow and ice near the summit, he said.

Spurr last erupted in 1992, but that and other recorded eruptions came from a cone on the south flank of the mountain, slightly below the summit. The current activity is directly beneath the summit, which has not erupted for 5,000 years, according to the Alaska Volcano Observatory.