The ground had been shaking for months beginning on December 16, 1011. The New Madrid Fault had suddenly become active. The first two powerful quakes shook the city of New Madrid, knocking people off their feet, opening fissures and snapping large trees. The second of the two quakes has been estimated to have registered 8.6 on the Richter Scale. This quake caused landslides that destroyed several communities. It was said that the tremor woke First Lady Dolley Madison thousands of miles away in Washington, D.C.
On February 7, 1812, the strongest of the earthquakes struck. Estimated at 8.8 magnitude, this one was arguably the strongest quake ever to strike the continental United States. It caused church bells to ring in Boston, Massachusetts and brick walls to fall in Cincinnati.
The Mississippi River turned brown and whirlpools suddenly developed as the riverbed bucked. Thirty boats were thrown over waterfalls created by the heaving of the riverbed. Small islands in the middle of the river disappeared. New Lakes, including Reedfoot Lake in Tennessee and Big Lake at the Arkansas-Missouri border were created in depressions caused by land subsidence. And finally, a phenomenon known as a fluvial tsunami caused the mighty Mississippi River to flow backwards for several hours.
No one will ever know for certain how many people actually died in the series of earthquakes by the time they ended in March 1812. The area was sparsely populated at the time, but at least 1,000 people likely lost their lives, and many more suffered physical and property damage.
Experts today continue to worry about the possibility that the New Madrid Fault will become active again. If the 19th century swarm of massive earthquakes were to happen today, the result would be absolutely disastrous over a wide area east of the Mississippi River.
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