unit 6
Earthquakes have plagued our lives for as long as people have inhabited the Earth.These dangerous acts of the Earth have resulted in great damage to human beings.
Earthquake damage depends on what area is hit .If an unpopulated region is struck ,there will be low loss of life or property.If it hits a large city which is densely populated,here may be serious injuries and destruction.
Earthquakes have the power to uproot trees and send them crashing into buildings.They can trigger landslides and cause flooding and tsunamis.Buildings and structures are also at risk .It is interesting to note that tall buildings will suffer the least damage if they are located directly at the epicenter .This is because they can withstand the up-and-down motion of P-waves.S-waves,on the other hang,occur far away from the epicenter ,and cause the greatest stress by shaking buildings from side.These buildings are often knocked off their foundations.
Buildings with thick,heavy walls do not resistshock waves very well.Violent earthquakes often cause structures to collapse ,burying people underneath.Brick buildings are the most vulnerable .The shaking of the earth is sometimes not the greatest disaster.It is in the subsequent fires and floods that often the greatest damage occurs.
Predicting an earthquake until now has almost been technologically impossible .With improvements in technology,lives have been saved and many more will.All that remains is to research what takes place before,during,and after an earthquake .This has been done for years to the point that a successful earthquake prediction is theoretically possible .However,accurate prediction of earthquake may take more years.