Earthquakes
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An entire branch of Earth Science is devoted to earthquake; it is called seismology. And seismologists are the group of scientists who study earthquakes. Most earthquakes take place near tectonic plates. The result of tectonic plates colliding, separating or slipping past each other is, many faults are formed. A fault is a break in the Earths crust along which blocks of the Earths crust slide relative to one another.There are three major types of faults, strike-slip fault, reverse fault and normal fault. One one of the biggest faults is the San Andreas fault in California. A seismograph is a machine that records the magnitude of earthquakes. The scale that measures the magnitude is the Richter Magnitude Scale. (my.hrw.com)