Earthquakes-being among the most de

Earthquakes-being among the most deadly natural hazards-strike without any prior warning, leaving catastrophe in their wake terrible loss of human lives as well as economic loss.
Technically, an earthquake (also known as tremor, quake or temblor) is a kind of vibration through earth’s crust. This vibration occurs as result of powerful movement of rocks in the earth’s crust. These powerful movements trigger a rapid release of energy that creates seismic waves that travel through the earth. Earthquakes are usually brief, but  may repeat over along period of time.(Earth Sience.2001)
Earthquakes are classified as large and small. Large earthquakes usually begin with slight tremors but rapidly take form of violent shocks. The vibrations from a large earthquake last for few days known as aftershocks. Small earthquakes are usually slight tremors and do not cause much damage. Large earthquakes are known to take down building and cause death and injury (Richter, 1935)
According to some statistics, there may be an average of 500,000 earthquakes every year but only about 100,000 can be felt and about 100 or so can cause damage each year.
The study of earthquakes is called seismology. Seismology studies the frequency, type and size of earthquakes. Earthquakes are measured using observation by seismometers. The magnitude of an earthquakes and its intensity is recorded on a numerical scale known as Richter scale. On this scale, 3 or less is hardly noticeable. Earthquakes with magnitude of more than 6.5 can cause heavy damage.
The effects of an earthquake are strongest in the area which near its epicenter. The extent of the earthquakes vibration and further damage to the region is partly dependent on the features of the ground. The worst possible damage occurs in the densely populated areas where structures are not built to withstand intense shaking. Damage and loss of life incurred during earthquake is due to falling buildings and flying glass and objects. In certain areas, an earthquake can cause mudslides that can bury areas under it. Powerful submarine earthquakes cause tsunami or a chain of fast moving waves in the ocean that ripple outward from earthquake epicenter toward coastal areas causing surmountable damage(http//:www.USGS.Org).On an average,1,000 earthquakes with intensities of 5.0 or greater are recorded each year.