When you hear that a sinkhole has swallowed a house, it's likely that you feel a spike of nervous fear followed by a few questions: What is a sinkhole? Why do they happen? Could this happen to me? Allow us to fill in a few details.
What is a sinkhole?
Also called a sink, snake hole, swallow hole, swallet, doline or cenote, a sinkhole is just what it sounds like: a big ol' hole in the ground. They can be really small (about 3 feet wide) or really, really big (about 2,000 feet wide). The smaller they are, the less chance they have of causing havoc.
This natural depression in Earth's surface is caused by something called "karst processes." In plain English, that means that rocks and sandstone dissolve under the ground's surface sometimes, which causes problems if you happen to have something important parked on top of the spot where one appears (such as your car). This process happens when there's an absence of water, caused by lack of rainfall or it being pumped out for nearby agricultural production. The dried limestone then begins to give way, creating a cave which can continue to expand until it reaches the surface.
Could this happen to me?
It could happen to you, but it's less likely to happen if you don't live in a hotbed of karst activity. It's said that northern Michigan and Florida see them more often than most places. China and Mexico also have some pretty epic sinkholes.