Yikes, that’s my neighborhood!
Scientists have finally figured out what might have caused a series of devastating earthquakes that struck the Midwest nearly 200 years ago at a set of faults that has confused geologists for a long time.
And the results suggest the region, still seismically active today, is going to keep shaking for a long time, and another big one will hit on the same 500-year cycle that has rocked the Heartland for as far back as records, legends and memory serve.
The largest of three or four big seismic events that stretched from December 1811 to February 1812 is called the New Madrid Earthquake and had an estimated 8.0 magnitude, strong enough to cause the nearby Mississippi River to temporarily flow backward. Its epicenter was in the town of New Madrid in southeast Missouri, near the Kentucky and Tennessee state lines. Hundreds of aftershocks followed for several years.
The damage from the New Madrid quake was bad enough in the early 19th century—half of the town was destroyed, but with many more people and buildings now in the area, a similar event in the region today would be devastating, seismologists and engineers agree.
The seismic zone today generates about 200 tiny quakes annually, but it also let loose a magnitude 4.1 quake in February 2005 and a magnitude 4.0 quake in June 2005. The U.S. Geological Survey says there is a 9-in-10 chance of a magnitude 6 or 7 temblor occurring in this area within the next 50 years.
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