How Earthquakes Happen
Earthquake
is one of the most destroying natural disasters. Unluckily it often
happens in several regions. Recently a horrible earthquake has shaken
West Sumatra. It has brought great damages. Why did it occur? Do you
know how an earthquake happens?
Earthquakes are usually caused
when rock underground suddenly breaks along a fault. This sudden release
of energy causes the seismic waves. It make the ground shake. When two
blocks of rock or two plates are rubbing against each other, they stick a
little. They don't just slide smoothly. The rocks are still pushing
against each other, but not moving. After a while, the rocks break
because of all the pressure that's built up. When the rocks break, the
earthquake occurs.
During the earthquake and afterward, the
plates or blocks of rock start moving, and they continue to move until
they get stuck again. The spot underground where the rock breaks is
called the focus of the earthquake. The place right above the focus is
called the epicenter of the earthquake.
Tidak ada komentar:
Posting Komentar