The earth's core is an ocean of trapped energy or forces. These forces are sometimes released through cracks and faults within the earth's crust. The sudden release of these forces often through very tiny openings, result in the movement of a plate of the earth's crust against another resulting in tremors that are referred to as earthquakes.
Earthquakes are measured in magnitudes that portray the depth, strength and the area covered by the tremor. Some of these earthquakes or tremors last from a few seconds to several minutes in some extreme cases. The magnitude of the earthquake and the duration of the tremor determine the scale of destruction it will leave in its wake. Sometimes, earthquakes are accompanied by landslides in the ocean bed when the epicenter is offshore, resulting in huge powerful waves of the ocean referred to as tsunamis.
These tsunamis escalate further the destruction already wrought by the earthquake. It is a horrifying spectacle that surviving victims of the preceding earthquake have to deal with, often under the emotional and psychological trauma of losing loved ones and properties. When the epicenters of earthquakes are on land or onshore, there is little or no risk of tsunamis except in cases of small islands. Nevertheless, damages will depend on the magnitude of the tremor. Sometimes, there are landslides and parting of the earth crust that accompany earthquakes, swallowing bridges and buildings along with humans. Search and rescue workers often have to race against time to rescue people who may be trapped under the rubble of collapsed buildings and victims washed away by accompanying tsunami waves. People have been known to hang on to life for up to a week before they are found and rescued but the hope of finding survivors diminish with each passing hour because most are injured and need urgent medical attention.