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Map showing one-year probability of accumulation of 1 centimeter (0.4 inch) or more of tephra from eruptions of volcanoes in the Cascade Range.
Map showing one-year probability of accumulation of 1 centimeter (0.4 inch) or more of tephra from eruptions of volcanoes in the Cascade Range.
Eruptions in the Cascade Range during the past 4000 years. USGS GIP 64
Eruptions in the Cascade Range during the past 4000 years. USGS GIP 64
Mount Jefferson (pointed peak in middle) and Three Sisters (to the right) in Oregon, south-facing aerial view as seen from Mount St. Helens.
Mount Jefferson (pointed peak in middle) and Three Sisters (to the right) in Oregon, south-facing aerial view as seen from Mount St. Helens.