A series of earthquakes that occurred in 1811-1812 near New Madrid, Mo. were the most widely felt earthquakes recorded in U.S. history. Its called the New Madrid earthquake largely because New Madrid was perhaps the most affected settlement. The quake actually began along the Saint Francis river in Arkansas about 65 miles southwest of New Madrid. Locals of New Madrid were awakened by shaking houses and falling chimneys. The magnitude of the earthquake has been estimated to be 8.0 or higher on the Richter Scale. They were felt over the entire United States outside of the Pacific coast. Large areas sank into the earth, new lakes were formed, and forests were destroyed over an area of 150,000 acres. "Houses, gardens, and fields were swallowed up" one source notes. But fatalities and damage were low because the area was sparsely settled then. Observed recordings set 1,874 separate quakes between December and March. After this observation it was recorded that the epicenter had moved closer to New Madrid. By March houses of New Madrid had fallen into the Mississippi River. This quake is credited with causing the Mississippi to flow backward. The New Madrid seismic zone, which is a result of the New Madrid quake, is a series of faults beneath the continental crust in a weak spot known as the Reelfoot Rift. It cannot be seen on the surface and the fault system extends 150 miles southwest of central Illinois. Scientists believe that catastrophic events like those of the 1811-12 happen in the New Madrid region every 550-1200 years. This means there is slight probability of an event greater than magnitude 8.0 within the next 15 years, and an even greater probability within 50 years. The people of the New Madrid area are taking precautionary methods to alleviate as many risk factors as possible from future seismic events such as the great "1811" quake. This enormous earthquake has been noted for even rocking bells in Boston, Ma. Stop!Duck!&Cover! It's an earthquake!!!
