Transcript for Earthquake - Risk to the Central U.S., segment 03 of 7


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Here in western Tennessee is visible evidence of the most severe series of earthquakes in the history of the United States. Before the earthquake struck in the winter of eighteen eleven and eighteen twelve, this was an eighteen-mile stretch of cypress forest. The earthquakes caused the ground to sink as much as twenty feet, creating what is known today as Real Foot Lake. While another earthquake of this magnitude is unlikely in the central United States for several hundred years, it is likely that the energy released by a quake of lesser magnitude will topple buildings and cause death and destruction. Doctor Otto Nutley, a geophysicist at Saint Louis University, has long been recognized as the leading authority on earthquake activity in the central United States.

If my calculations are correct, there's enough energy stored up in the rock right now to produce a magnitude seven point six earthquake, which, if it were to occur, would be a very, very large earth - it would be a major earthquake.

Since nineteen seventy-four, scientists have detected two hundred earthquakes a year of at least one point zero on the Richter Scale in the central United States. Because it takes sensitive instruments to detect many of these quakes, few people are aware of the danger. The quakes share no single fault and have been centered near such distant cities as Lawrenceville, Illinois; Cleveland, Ohio; and Marked Tree, Arkansas. Scientists tell us stress is constantly building along the earthquake faults within the central United States. Sooner or later, the energy will be released in the form of a major earthquake.

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