The magnitude 7 earthquake that struck Haiti yesterday is the strongest earthquake to hit the region in more than two centuries, geologists say. (SeeHaiti earthquake pictures.)
While earthquakes are not uncommon in the Caribbean island country, the recent Haiti earthquake's intensity surprised experts.
"It's quite strange" from a historical perspective, said Julie Detton, a geophysicist with the U.S. Geological Survey.
Haiti is part of the island of Hispaniola, which also hosts the Dominican Republic. The last major earthquake to strike Haiti's side of the island was in 1860.
Yesterday's initial earthquake, which struck at about 5 p.m. local time yesterday, spawned dozens of aftershocks, about 15 of which were magnitude 5 or greater.
Whether the earthquake could trigger other major quakes is not known.
"It's not something that we can project is going to happen," Detton said.
"But definitely if you're moving two [plates] in one area, you're building up stress and strain in another."
Haiti Earthquake: Seismic Stresses
The Haiti earthquake was caused by the release of seismic stresses that had built up around two tectonic plates.
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