Science behind Earthquakes
The Science Behind Earthquakes
In recent news, there have been reports of earthquakes happening in Mexico and Japan. The 4.3 magnitude earthquake that hit Mexico on November 13th thankfully did not cause much damage. The next day, a 7.1 magnitude earthquake struck the southwest coast of Japan and triggered a tsunami. We hear about earthquakes happening all the time, but what exactly are they and what causes them? Earthquakes are caused when the tectonic plates underneath the surface break and shift. The point at which they break is called a fault. When the plates move they release energy in the form of vibrations, which we feel as an earthquake. The magnitude of the earthquake is determined from recordings of the waves (called seismic waves) taken from a seismograph. The focus of an earthquake is the point at which the waves originated underneath the ground and the epicenter is the point directly above the focus on the surface. The magnitude of earthquakes is measured on the Richter scale, which increases by 30 fold with each increasing number from 1 through 10. It is determined from data collected from a seismograph. The Modified Mercalli intensity scale ranges from I to XII and measures the effects of an earthquake based on people. Although earthquakes are already destructive, they may sometimes trigger even more devastating natural disasters such as landslides and tsunamis, which are underwater earthquakes. We aren’t able to stop natural disasters such as earthquakes from happening but it is always best to stay informed and use caution when one might occur.
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