ANCHORAGE, Alaska (Reuters) - After 10 days of relative calm, Alaska's Augustine Volcano roared back to life late on Friday, shooting a cloud of ash 40,000 feet into the sky.
It was the 10th explosion since January 11, when the 4,134-foot (1,260-meter) volcano in southern Cook Inlet began an eruptive phase, reported the Alaska Volcano Observatory, a joint federal-state office.
As of late Friday, there were no reports of ash settling onto any of the nearby communities, but some was expected to drift onto Kodiak Island, southeast of the peak, said Janet Schaefer, a geologist with the volcano observatory.
Because it was dark when the eruption occurred, the ash was not visible to casual observers, she said. "We do see from satellite imagery that the ash cloud is moving southeast," she said.
Augustine is located about 175 miles southwest of Anchorage. The conical-shaped peak forms its own uninhabited island in Cook Inlet, the channel that runs from the Anchorage area to the Gulf of Alaska. It is the most active of Cook Inlet's volcanoes.
Despite more than a week of quiet, experts had anticipated another eruption at Augustine, Schaefer said. Seismic activity had been building at the site. "We knew something was coming up shortly," she said.
Before this month, Augustine's previous eruptive periods occurred in 1986 and 1976. The current activity "is looking a lot like what happened" in those years, with a series of explosive eruptions interspersed with days of quiet, Schaefer said.