Earthquakes scenes are really tragic. One who hadn’t experienced it will ask will all this happen by a simple earthquake. That much is the destruction caused due to earthquakes. In my previous article I told you something about earthquakes.Now we can look how earth quakes occur ?
We can familiarize a term first namely fault. A fault is where blocks of crust on either side are moving relative to one another. The average rate of movement is one millimeter per year approximately. If this movement happens gradually it would pose some problems to people who lives near by. But rocks never follows our willingness. The strain goes on building up for centuries and reaches a critical level. After critical level if it is increased it may lose all control so far causing strong quake.
There are many fault lines on earth’s crest. Once a fault has given way at one point, slip movement may occur along its whole length. The length may extend to hundreds and thousands of kilometers. The movement is usually restricted to a shorter portion of the whole vault. Some seismic waves are strong while some others are weak. The strongest seismic waves are usually generated at the initial break point. Hence closer to the break point the energy outbreak will be higher and hence the destruction also greater. If the break point is near to the surface the destruction caused will be very very high.
You might have heard the earthquake focus. Do you know what is this. It is nothing but the earthquake break point itself. The point on the surface of earth directly above earthquake focus is called epicenter. After earthquake some readjustments occur close to the focus. Hence small small aftershocks are observed for some more days. In some terrible cases this may continue for some years also !! This type of energy release are called waves. The name is due to the way they move. The waves that travel along the surface of the ground do more harm in the earthquake cases. They may be up and down or side to side.
Earthquake can be predicted earlier. Geologists had discovered some areas prone to frequent earthquakes. The people in that region are staying there expecting it at any time. Buildings and dwellings in such areas are built in such way that least destruction and loss occurs due to the earthquake.