Earthquakes
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Earthquakes have much more to them than just shaking the ground. there is a whole brach of science that is about these natural disasters called seismology. Most of these earthquakes happen around tectonic boundaries, which are giant pieces of earths thin, outermost layer and move around on the top of plastic rock. Earthquakes occur along faults because of the sliding of the plates. A fault is a break in the Earth's crust along which blocks of crust slide relative to another. Deformation is the change in the shape of rock in response to stress there are two type of deformation, plastic and elastic deformation. Plastic deformation does not lead to an earthquake and can make rocks undergo deformation. Elastic deformation does lead to an earthquake. This can make the rocks stretch father without breaking, but will still eventually break. This is just like stretching rubber band until it snaps. earthquake zones are places where a large number of faults are located. But, not all faults are located at earthquake zones, sometimes earthquakes happen along faults that are in the middle of a tectonic plate. Earthquakes are measured in seismograms that are created by a seismograph. A seismogram is a tracing of earthquake motion and is made by a seismograph. A seismograph is an instrument located at or near the surface of the Earth that records seismic waves, which are waves of energy that travel through the Earth. Seismologists use seismograms to find when an earthquake began. They also use seismograms to find an earthquakes epicenter. An epicenter is the point on the Earth's surface directly above the earthquakes' starting point, which is the focus. A focus is the point inside the Earth where an earthquake begins. The Richter Magnitude Scale is the scale that has been used by seismologist to measure the strength of earthquakes. There are 6 rates on the Richter scale, number two through seven. 2 is only can be detected by a seismograph, 3 is can be felt at the epicenter, 4 is can be felt by most people in the area, 5 causes damage at the epicenter, 6 causes widespread damage, and 7 is the worst causing great widespread damage. when an earthquake happens, make sure and have extra supplies ready, a meeting spot with your family, and if you are in a car stop it and turn of the car. If you live along a fault, you should always be prepared and retro fit your home or building. Retro fitting is the process of making a building or home earthquake resistant.