"Stretch zones primarily experience sinking ground, as the support in the rock strata is stretched thin. Thus, buildings implode and gas and water mains break."
The man who disappeared after being swallowed up by a large sinkhole that opened under his bedroom in Seffner, Fla., is still missing. The state is especially prone to sinkholes because underneath the ground is limestone, a porous rock that easily dissolves in water, sometimes forming a hole in the earth. Here's a look at other sinkholes in Florida.