How to tell when a volcano will 'wake up'

Volcano program coordinator Brian Terbush explains how we can tell when a volcano like Mount St. Helens will "wake up."
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Volcano program coordinator Brian Terbush explains how we can tell when a volcano like Mount St. Helens will "wake up."

Mount St. Helens rattled by 2nd largest earthquake in area since 1981, then 15 aftershocks

January 03, 2018 08:02 AM