Mount St. Helens Blows Out Its North Face
CONFIRMED88% CONFIDENCEThe moment is recorded to the second: "An earthquake at 8:32:11 am PDT (UTC-7) on May 18, 1980, caused the entire weakened north face to slide away", which is 15:32:11 UTC.[1]
An earthquake at 8:32 a.m. local time dropped the volcano's weakened north face away in the largest subaerial landslide on record, uncorking a lateral blast toward Spirit Lake. Fifty-seven people were killed.
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