Haiti sits in the boundary region between the Caribbean Plate and the North American Plate. The theory of plate tectonics developed in the 1960s and 1970s. According to the theory, which is well established, the outer layer of the earth, the lithosphere, is composed of seven major tectonic plates. These plates are known as: the African, North American, South American, Eurasian, Australian, Antarctic, and Pacific plates (there are some minor plates, including the Caribbean Plate).
The plates are solid, rigid masses which float on the molten inner layer of the earth, allowing them to move about. A plate may drift by as much as 2 to 10 centimeters per year. Although a velocity of 0.00001 km per annum may not sound very fast, when you imagine the mass associated with these plates and remember that the kinetic energy they hold is the product of half of the mass times the square of the velocity (KE = 1/2mv2), it is easy to understand the tremendous energy that plates contain. It has been calculated that the energy associated with an 8.6 magnitude earthquake is equivalent to 10,000 times the explosive force of the nuclear weapon which was dropped on Hiroshima.
The plates come into contact with each other at the plate boundaries. They can continue to come together or drift apart for millennial – indeed if you look at a map of the world, you can see that most of the continental masses now separated by large distances were once part of a single land mass known as Gondwana. Geologists believe that the separation of this super continent took place 130 million years ago.