ベルクナップ・クレーター

The Belknap Crater area near McKenzie Pass in Oregon, north of the Three Sisters volcanoes, was the source of one of the largest concentrations of youthful volcanism in the Cascade Range. The basaltic to basaltic andesite Belknap shield volcano, topped by the Belknap Crater pyroclastic cone and the Little Belknap shield volcano immediately to the east, have produced widespread late Holocene lava flows on all sides, much of which took place between about 3,000 and 1,500 years ago. Eruptions from the NE base of Belknap crater produced lava flows that traveled 15 km W into the McKenzie River valley.