How Big Was the New Madrid Fault Earthquake?

By Robert Palmer

The New Madrid Fault is a geological fault line that runs through the central United States. It has been the source of several major earthquakes, including one of the largest in American history.

The New Madrid earthquake of 1811-1812 was so powerful that it could be felt as far away as Boston and was said to have rung church bells in Philadelphia. But just how big was this historic earthquake?

The Magnitude of the New Madrid Earthquake

The magnitude of an earthquake measures the amount of energy released during the event. The New Madrid earthquake is estimated to have had a magnitude between 7.5 and 7.9 on the Richter scale, making it one of the largest earthquakes ever recorded in North America.

The Impact on the Mississippi River

One of the most significant effects of the New Madrid earthquake was its impact on the Mississippi River. The ground shaking caused by the quake caused whole sections of riverbank to fall into the water, creating temporary dams and altering the course of the river.

  • In some places, parts of the river were pushed upstream, causing flooding in previously dry areas.
  • In others, sandbars and islands were formed as sediment was deposited along newly-formed banks.
  • At one point, a section of river actually flowed backward for several hours.

The Human Impact

Although sparsely populated at that time, settlements along both sides of Mississippi felt strong ground shaking which lasted for more than two minutes. Some accounts even reported seeing cracks open up in fields and forests.

Despite its power, however, there were relatively few deaths associated with this quake because it occurred in such a sparsely populated region; nonetheless many people were injured or lost their homes due to collapsing structures.

Conclusion

In conclusion, the New Madrid earthquake of 1811-1812 was an incredibly powerful event that left a lasting impact on the landscape of the central United States. While its magnitude was not as high as some other famous quakes around the world, its effects on the Mississippi River and surrounding areas were profound. Today, scientists continue to study this earthquake and others like it in order to better understand the nature of seismic activity and how we can prepare for future events.