EARTHQUAKES

At the beginning of our 'Active Planet' topic we ran a drill to help us prepare should we ever be involved in an earthquake.  4G set up a disaster relief centre in their classroom for victims of the earthquake.  Now we have been thinking more about earthquakes and the devastation that often occurs because of them.

Pushing plates cause earthquakes

Before we begin discussing earthquakes it is very important to know how they are caused.  We have previously mentioned plate tectonics.  When two of the plates meet they sometimes push together, causing a huge build up of pressure until suddenly one plate gives way and slips beneath the other plate.  This sudden jerk movement of the slipping plate causes the ground to shake and  the vibrations can be felt on the ground we walk on.  Sometimes this action is so forceful buildings can collapse and roads can break apart.  

Have a look at this video to get more of an idea about earthquakes.  Earthquake information clip

The clip below gives you an idea of how earthquakes can cause harm to people.  When you watch this clip think about how the people might be feeling?  Have a look at how buildings are damaged.  When the school girl is speaking imagine that happened in your school.
News report - Earthquake in New Zealand

Earthquakes in the ocean can cause tsunamis to occur.  This makes earthquakes even more deadly and can cause death and destruction for people who did not even feel the tremor of the earthquake as it happened.  A tsunami is a huge wave that can be even taller than buildings.  The wave will travel extremely fast and wash in over a whole town or city.  This leaves a huge flood causing many deaths and destroying buildings.

The tsunami is caused when two of the plates meet and like we already mentioned they keep pushing together until one plate slips.  The ocean floor jerks upward and this causes the water to also move upward at a really fast pace.  The water has literally been pushed forward so it is now speeding towards the coast where there might be a town or village.  This clip helps you get a more visual image of how a tsunami would happen.  Explaining how tsunamis happen

So as we can see, earthquakes can cause loss of lives in many different ways.  Engineers are always trying to come up with different ways to make stronger buildings that can withstand the violent tremors of earthquakes and stay standing when the ground moves.