The New Madrid Fault Line is a significant geological feature located in the central United States. It is an intraplate seismic zone that stretches from northeastern Arkansas to southern Illinois.
The fault line takes its name from the town of New Madrid, Missouri, which was the site of a series of powerful earthquakes in 1811 and 1812. But what kind of fault line is the New Madrid?
The New Madrid Fault Line
The New Madrid Fault Line is not a typical fault line. Unlike most fault lines, which are located at the boundaries between tectonic plates, the New Madrid Fault Line lies entirely within the North American Plate. This makes it an intraplate seismic zone.
Intraplate seismic zones are rare but not unheard of. They occur when stresses build up within a plate and cause it to rupture along pre-existing weaknesses, such as ancient faults or zones of weakness in the crust.
History
The history of the New Madrid Fault Line dates back millions of years. However, it was not until 1811 and 1812 that the fault line made its mark on human history.
In December 1811, a series of powerful earthquakes struck near New Madrid, Missouri. These earthquakes were some of the strongest ever recorded in North America, with estimated magnitudes ranging from 7.5 to 8.0.
The earthquakes were felt across much of eastern North America and caused widespread damage to buildings and infrastructure in the region. They even caused the course of the Mississippi River to temporarily flow backward!
Fortunately, there were relatively few casualties as most people living in the sparsely populated region had already fled due to rumors about an impending earthquake.
There are three types of faults: normal faults, reverse faults, and strike-slip faults. – Normal faults occur when rocks are pulled apart by tension forces.
– Reverse faults occur when rocks are pushed together by compression forces. – Strike-slip faults occur when rocks slide past each other horizontally.
The New Madrid Fault Line is a strike-slip fault, which means that the movement of the rocks along the fault line is mostly horizontal. However, there is also a component of vertical movement, which can lead to uplift or subsidence of the ground surface.
Conclusion
In conclusion, the New Madrid Fault Line is an intraplate seismic zone located in the central United States. It is a strike-slip fault that has caused some of the strongest earthquakes ever recorded in North America. While earthquakes on the New Madrid Fault Line are relatively rare, they have the potential to cause significant damage and should not be taken lightly.