Did the New Madrid Earthquake Make the Mississippi River Flow Backwards?
The New Madrid earthquake of 1811-1812 is one of the most significant seismic events in American history. It was a series of powerful earthquakes that struck the central United States, centered around the town of New Madrid, Missouri. The region experienced several major earthquakes during this time, with magnitudes estimated to be as high as 7.5 to 7.9 on the Richter scale.
The Power of the New Madrid Earthquake
The New Madrid earthquake was so powerful that it caused widespread destruction across a vast area, even affecting cities as far away as St. Louis and Cincinnati. The shaking was so intense that it reportedly caused church bells to ring in Boston, Massachusetts, almost 1,000 miles away!
One intriguing aspect of this earthquake is a persistent myth that claims it made the mighty Mississippi River flow backwards. Let’s dive into this fascinating topic and separate fact from fiction.
The Myth: Did the Mississippi River Really Flow Backwards?
Contrary to popular belief, there is no scientific evidence supporting the claim that the New Madrid earthquake made the Mississippi River flow backwards.
Rumors and exaggerated accounts from eyewitnesses likely contributed to this misconception. People observed unusual behavior in river channels during and after the earthquake, including temporary changes in water levels and new land formations known as “sunk lands.” However, these phenomena are not indicative of a river flowing backwards.
Temporary Changes in Water Levels
During an earthquake, seismic waves can temporarily disrupt water flow by causing fluctuations in river levels. This can result in localized flooding or temporary drops in water levels but does not imply a reverse flow.
Sunk Lands and Sand Blows
Another curious phenomenon associated with the New Madrid earthquake is the formation of “sunk lands.” These were areas where the ground sank, creating new depressions that sometimes filled with water.
Additionally, sand blows occurred when pressurized groundwater forced sand and water to erupt onto the surface. While these events may have altered the course of smaller streams or created temporary backflows, they did not cause the Mississippi River to reverse its flow.
Scientific Explanations
So, if the Mississippi River did not flow backward during the New Madrid earthquake, what caused these rumors to persist? One possible explanation is that eyewitnesses were confused by other seismic effects.
- Liquefaction: The shaking caused by earthquakes can liquefy saturated soils, turning them into a quicksand-like substance. Witnessing liquefaction in riverbanks or tributaries might have given the impression of a river flowing upstream.
- Seiches: Seiches are standing waves that can occur in enclosed bodies of water, such as lakes or bays, during an earthquake. These waves can create unusual water movements but do not reverse the natural flow of a river.
The Legacy of the New Madrid Earthquake
The New Madrid earthquake left a lasting impact on both geology and American history. It significantly influenced our understanding of seismic hazards in central North America and prompted further studies into intraplate earthquakes.
The myths surrounding this event also serve as reminders to critically evaluate historical accounts and separate fact from fiction. While it is tempting to believe extraordinary claims, scientific evidence should always be our guiding light.
In conclusion, while the New Madrid earthquake was undoubtedly a powerful and influential seismic event, it did not cause the Mississippi River to flow backward. The myth likely stemmed from a combination of confusion, exaggeration, and misinterpretation of seismic effects.