The 10,200-foot volcano, located about 100 miles southwest of Anchorage, shot plumes of ash up to 9 miles into the atmosphere above the Alaska Peninsula.

Scientists at the Alaska Volcano Observatory cautioned that the mountain is currently in a dome-building phase, making it difficult to warn people about when an eruption is likely to occur.

Mud and water flowing down the flanks of Redoubt have uprooted hundreds of trees and clogged the Drift River Valley with debris.

Chevron’s Drift River Terminal, near the base of the volcano, was forced to suspend operations due to the menacing debris flows.

The facility stores about 145,000 barrels of Cook Inlet crude oil on site, which mainly supplies a nearby refinery.

Redoubt last erupted in 1989-90, when it produced sporadic explosions over a five-month period.

Photo: Cyrus Read Alaska Volcano Observatory