Saturday’s powerful earthquake in Haiti has killed hundreds. And the destruction comes just 11 years after a temblor killed tens of thousands, if not hundreds of thousands of people.
Haiti sits near the intersection of two tectonic plates that make up the Earth's crust.
Earthquakes can occur when those plates move against each other and create friction.
“Hispaniola sits in a place where plates transition from smashing together to sliding past one another,” said Rich Briggs, a research geologist at the U.S. Geological Survey’s Geologic Hazards Science Center.
“It’s like a rock stuck in the track of a sliding glass door,” he said. “It just does not want to move smoothly because it’s got so many different forces on it.”
Haiti is also densely populated. Plus, many of its buildings are designed to withstand hurricanes — not earthquakes.
Those buildings can survive strong winds but are vulnerable to collapse when the ground shakes.
Authorities on Sunday raised the casualty toll to at least 1,297 dead and 2,800 injured.