Earthquakes and Cuba

Another earthquake hit near Corralillo, Cuba over the weekend

MIAMI – Over the weekend, another earthquake hit near Corralillo, Cuba, approximately 110 miles east of Havana.

This was the fourth earthquake since a magnitude 5.0 impacted the same area in January. The recent tremor was a magnitude 4.7, not exactly a major quake but enough to stir the curiosity.

The truth is that Cuba is a seismically active area with a history of major earthquakes, some in excess of 7.0. However, most of Cuba's quakes are expected to occur along the southeastern coast.

In 1766, a major quake with a magnitude of 7.6 rocked the area near Santiago de Cuba. The recent quakes east of Havana are rare and have been felt all the way up into the Keys and parts of Broward County.

To understand why this is happening, we have to zoom out and focus on the big picture. Hundreds of millions of years ago, the world's continents were one giant landmass known as Pangaea.

Over time, a giant rift occurred tearing these continents apart. Have you ever noticed how the coastlines of the America's line up with the coastlines of Europe and Africa? This separation of landmasses continues today through the process of plate tectonics.

Our continents are sitting on plates that are constantly shifting and moving. For example, there is the North American plate, the African plate and so on. The most recent quakes in Cuba have occurred in a place where the North American plate borders the Caribbean plate. These two plates have been pressing against each other, creating the Cuban Fold and Thrust Belt. This type of fault is very rare but obviously capable of releasing energy.

The Caribbean is a hotbed for seismic activity. In 2010, the catastrophic magnitude 7.0 quake that slammed Haiti killed more than 160,000 people. In 1995, the volcano on the island of Montserrat forced the permanent exodus from the capital, Plymouth.

While northern Cuba is on the extreme northern fringe of the Caribbean seismic map, it serves as a reminder that this old planet of ours is constantly moving and changing. You and I are just going along for the ride.