The Amazon rainforest produces more than 20% the world's oxygen supply.
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The Niagara Falls moves upstream at an average rate of about 295ft a century!
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An earthquake on Dec. 16, 1811 caused parts of the Mississippi River to flow backwards.
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If Antarctica's ice sheets melted, the worlds oceans would rise by 60 to 65 metres (200 - 210ft) - everywhere
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Every year, Alaska has about 5,000 earthquakes.
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More than a dozen men have stood on the surface of the moon, but only three have been to Challenger Deep in the Marianas Trench, the deepest known spot in the ocean.
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Louisiana is the only state that grows in land area every year (Due to alluvial deposits from the Mississippi River).
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