Earthquakes are caused by the abrupt release of stored energy within the earth’s crust. This release of energy is much like that which is released when a stretched rubber band breaks. .
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Earthquakes are caused by the abrupt release of stored energy within the earth’s crust. This release of energy is much like that which is released when a stretched rubber band breaks.
The Eastern Caribbean is an example of an island arc system formed at a convergent plate boundary (more specifically, at a subduction zone, where two tectonic plates meet and the denser plate is forced beneath the lighter plate).
This is the main cause of the volcanic and seismic activity in the Eastern Caribbean.
Most of the earthquakes occurring in the Eastern Caribbean are either tectonic or volcanic in origin.
Tectonic earthquakes are generated when plates move as accumulated energy is released.
Volcanic earthquakes are generated by the movement of magma within the lithosphere. Since magma is less dense than the surrounding rock, it rises to the surface, breaking the rock as it moves, thereby generating earthquakes.
More than 75% of the world's earthquakes occur at convergent plate boundaries. The countries of the Eastern Caribbean are, therefore, highly susceptible to earthquakes
The motion of the ground during earthquakes is recorded by instruments known as seismographs. The ground motion that people notice comes from a release of energy that radiates outward in all directions as seismic waves, which travel through the earth.
There are two basic types of seismic waves- body waves and surface waves. Generally, the first jolt felt during an earthquake is the push-pull body wave, or P wave, as it reaches the surface. A second jolt is another type of body wave, called an S wave.
The fastest wave, and therefore the first to arrive at a given location.Also known as compressional waves, the P wave alternately compresses and expands material in the same direction it is traveling.Can travel through all layers of the Earth.Generally felt by humans as a bang or thump.
The S wave is slower than the P wave and arrives next, shaking the ground up and down and back and forth perpendicular to the direction it is traveling.Also know as shear waves
Surface waves follow the P and S waves.Also known as Rayleigh and Love waves.These waves travel along the surface of the earth.