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When did Lassen Peak last erupt?

The most recent eruptive activity at Lassen Peak (California) took place in 1914-1917. This eruptive episode began on May 30, 1914, when a small phreatic eruption occurred at a new vent near the summit of the peak. More than 150 explosions of various sizes occurred during the following year.By mid-May 1915, the eruption changed in character; lava appeared in the summit crater and subsequently...

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When did Lassen Peak last erupt?

The most recent eruptive activity at Lassen Peak (California) took place in 1914-1917. This eruptive episode began on May 30, 1914, when a small phreatic eruption occurred at a new vent near the summit of the peak. More than 150 explosions of various sizes occurred during the following year.By mid-May 1915, the eruption changed in character; lava appeared in the summit crater and subsequently...

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