Human structures become treacherous during earthquakes.

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Total Geomagnetic Reversal

Now here's a real beauty of a doomsday scenario: the Earth's North and South poles suddenly flip places, causing planetary rotation to grind to a halt and start rotating backward as if someone slammed the brakes on the family vacation van and then threw it into reverse. Imagine the oceans rising up to swallow cities. Imagine the earthquakes felling mountains.

Sound terrifying? Well, here's the scoop: While geomagnetic reversal can and does occur, it would take thousands of years to happen, and there's no evidence to suggest it would result in global cataclysm. Rest assured that it certainly won't alter planetary rotation. And as you might imagine, any inkling that such a major geomagnetic reversal will occur in 2012 is complete conspiracy theorist nonsense.

How to Survive: Still, it pays to be sure, right? Should the Earth begin to shake, FEMA recommends that if you're indoors, seek shelter under a sturdy table or against an inside wall. If you're outdoors, keep away from buildings, streetlights and power lines. If you're in a moving vehicle, pull over away from structures or trees.

Next up, learn what to do when ancient Chinese coins threaten the planet.