The United States has 161 active volcanoes, but a new study by the U.S. Geological Survey finds that 18 pose a "very high threat" of a dangerous eruption.
Topping the list is Hawaii's Kilauea, which sent lava flows across the state's Big Island earlier this year. Of the others on that list, several are in the Cascade Range: Mount St. Helens and Mount Rainier in Washington. In Oregon, Mount Hood ranks as Oregon's most threatening volcano, followed by the Three Sisters, Newberry, and Crater Lake.
This same report found the caldera at Yellowstone to rank No. 21 in terms of its threat. The Jackson Hole News& Guide noted that it hasn't erupted in 630,000 years or produced surface magma flows in 70,000 years.
The Bend Bulletin explained that with the exception of the Hawaiian volcano, most of the changes in the list that was last assessed in 2004 were the result of evolving understanding of how certain volcanoes behave. It did not define what constitutes a "very high threat."
But whatever the threat today, eruptions in the past have been relatively uncommon in the Cascade Range. Garibaldi, near Whistler, was last active between 10,700 to 9,300 years ago. Hood was last active about 200 years ago, although there was a sequence of steam explosions in the mid-19th century.
Shasta, in northern California, last erupted 300 years ago but continues to steam, to the benefit of John Muir, who spent a night atop the volcano. About halfway south to Lake Tahoe, Mt. Lassen erupted between 1914 and 1917.
Several of these volcanoes—including Rainier, Hood and Shasta—have ski areas on their flanks, while Mt. Bachelor is relatively proximate to the Three Sisters east of Bend.
