When did the most severe earthquake in American history occur?
The New Madrid Earthquakes, a series of quakes beginning on December 16, 1811, and lasting until March 1812, is considered to be the most severe earthquake event in U.S. history. These earthquakes, located in New Madrid, Missouri, shook more than two-thirds of the United States and were felt in Canada. They changed the elevation of land by as much as 20 feet (6 meters) and altered the course of the Mississippi River. The New Madrid Earthquakes even created new lakes, such as Lake St. Francis west of the Mississippi and Reelfoot Lake in Tennessee. Because the area was so sparsely populated, there were no deaths known to have occurred as a result of the earthquakes. Scientists agree that at least three, and possibly five, of the earthquakes had surface wave magnitudes of 8.0 or greater on the Richter scale. The largest was probably a…
