How Sinkholes Work

Maybe you've seen one on the news: a giant yawning hole in the road, swallowing an unfortunate car that was in the wrong place when the Earth opened up without warning. Or maybe you were on vacation in Mexico and saw one of the country's beautiful cenotes, or water-filled pools, surrounded by verdant green. Both of these geological features are sinkholes, formations that are much more than holes in the ground. Though many are less than 100 feet (30 meters) deep, sinkholes can look like ponds, cover hundreds of miles or fit discreetly in your backyard

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