Interactive: Measuring earthquakes

CNN

A major earthquake struck just off the Haitian capital Port-au-Prince on Tuesday, sparking a tsunami watch for parts of the Caribbean, according to the U.S. Geological Survey.

There was no immediate report of damage or injuries from the quake. However, The Associated Press reported that a hospital had collapsed.

The quake had a reported magnitude of 7.0 and was centered about 10 miles (16 km) off the coast and about 6 miles (10 km) underground, according to the USGS.

A tsunami watch was posted for Haiti and parts of Cuba, the Dominican Republic and the Bahamas, but historical data suggests a destructive, widespread tsunami was not a threat, the USGS reported.