Forget the Mayans: 5 actual apocalyptic possibilities
3. Super Volcano
Credit: AP
Not all apocalyptic menaces come from outer space. One credible threat is a "super volcano" that would spit out so much sulfur, carbon dioxide and ash that it would change the climate enough to alter the food chain and lead to human death. Geologists have found traces of huge volcanoes around the world. One of them is actually under Yellow Stone National Park in Wyoming.
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