Essay on earthquake

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Earthquakes have plagued our lives for as long as people have inhabited the earth. These dangerous acts of the earth have been the cause of many deaths in the past century. So what can be done about these violent eruptions that take place nearly with out warning? Predicting an earthquake until now has almost been technologically impossible. With improvements in technology, lives have been saved and many more will. All that remains is to research what takes place before, during, and after an earthquake. This has been done for years to the point now that a successful earthquake prediction was made and was accurate. This paper will discuss a little about earthquakes in general and then about how predictions are made. Earthquake, “vibrations …show more content…
The modern seismograph was invented in the early 20th century by the Russian seismologist Prince Boris Golitzyn. “His device”, using a magnetic pendulum suspended between the poles of an electromagnet, “ushered in the modern era of earthquake research.” (Nagorka 1989) “The ultimate cause of tectonic quakes is stresses set up by movements of the dozen or so major and minor plates that make up the earth's crust.”(Monastersky Oct, 95) Most tectonic quakes occur at the boundaries of these plates, in zones where one plate slides past another-as at the San Andreas Fault in California, North America's most quake-prone area-or is subducted (slides beneath the other plate). “Subduction-zone quakes account for nearly half of the world's destructive seismic events and 75 percent of the earth's seismic energy. They are concentrated along the so-called Ring of Fire, a narrow band about 38,600 km (about 24,000 mi) long, that coincides with the margins of the Pacific Ocean. The points at which crustal rupture occurs in such quakes tend to be far below the earth's surface, at depths of up to 645 km (400 mi).” (Monastersky Dec, 95) Alaska's disastrous Good Friday earthquake of 1964 is an example of such an event. Seismologists have devised two scales of measurement to enable them to describe earthquakes quantitatively. “One is the Richter scale-named after the American seismologist Charles Francis Richter-which measures the energy released

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