<P> The pressure of the South American Plate to the east of the Caribbean causes the region of the Lesser Antilles to have high volcanic activity . There was a very serious eruption of Mount Pelée in 1902 which caused many casualties . </P> <P> The Caribbean sea floor is also home to two oceanic trenches: the Cayman Trench and Puerto Rico Trench, which put the area at a high risk of earthquakes . Underwater earthquakes pose a threat of generating tsunamis which could have a devastating effect on the Caribbean islands . Scientific data reveals that over the last 500 years the area has seen a dozen earthquakes above 7.5 magnitude . Most recently, a 7.1 earthquake struck Haiti on January 12, 2010 . </P> <Ul> <Li> List of islands in the Caribbean </Li> </Ul> <Li> List of islands in the Caribbean </Li>

Where does the ocean floor go to after a 180 million years