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Glaciers have played an important role in modifying the landscape of the Long Valley area before, during, and after the enormous caldera-forming eruption 760,000 years ago.
Glacial striations, moraine deposits beneath the town of Mammoth Lakes and in major river valleys, jagged cirques, and ice-rafted boulders scattered on ancient shorelines of the large lake that once filled the caldera are clear evidence that several episodes of recent glaciationoccurred here.
Glaciers have played an important role in modifying the landscape of the Long Valley area before, during, and after the enormous caldera-forming eruption 760,000 years ago.
Glacial striations, moraine deposits beneath the town of Mammoth Lakes and in major river valleys, jagged cirques, and ice-rafted boulders scattered on ancient shorelines of the large lake that once filled the caldera are clear evidence that several episodes of recent glaciationoccurred here.