An earthquake on Dec. 16, 1811 caused parts of the Mississippi River to flow backwards.
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There are more than 50,000 earthquakes throughout the world every year!
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The Sahara desert expands at about 1km per month.
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One cubic mile of seawater contains about 50 pounds of gold.
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Israel's Dead Sea is 1,312 feet below sea level.
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Check your map! Virginia extends farther west than West Virginia.
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The Amazon rainforest produces more than 20% the world's oxygen supply.
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The North Atlantic gets 2.5 centimetres (1in) wider every year.
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