The New Madrid Fault is the most active seismic area in the United States east of the Rocky Mountains. The fault is located in southeastern Missouri, northeastern Arkansas, western Tennessee, western Kentucky and southern Illinois. Southwestern Indiana and northwestern Mississippi are also close enough to receive significant shaking from large earthquakes. Despite being far away from current plate boundaries, the New Madrid Fault is a dangerous zone because of the active faults that are actually buried 100 to 200 feet deep in soft river deposited soils of alluvium, making these faults harder to study because of their location underground. Most faults are found on the surface making them easier to analyze for any activity. Microseismic earthquakes (magnitude less than 1.0 to about 2.0), measured by seismographs but not felt by humans, occur on average every other day in this zone, on average around 200 microseismic earthquakes
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A series of three to five major earthquakes (believed to have been magnitude 7.0 or larger earthquakes) occurred in the area in the two month period between Dec. 16, 1811 and Feb. 7, 1812. Several thousand additional “smaller” earthquakes occurred during the three month period from Dec. 16, 1811 to March 16, 1812. Due to the harder, colder, drier and less fractured nature of the rocks in the earth’s crust in the central United States, earthquakes in this region can shake and damage an area approximately 20 times larger than earthquakes in California and most other active seismic areas. The frequency of large earthquakes in the zone is still being debated, but the New Madrid Fault appears to be about 30 years overdue for a magnitude 6.3 quake because the last quake of this size occurred one hundred years ago at Charleston, Missouri, on Oct. 31, 1895 (a magnitude 6.7). A magnitude 6.3 quake near Lepanto, Arkansas, on Jan. 5, 1843, was the next earthquake of this
A series of three to five major earthquakes (believed to have been magnitude 7.0 or larger earthquakes) occurred in the area in the two month period between Dec. 16, 1811 and Feb. 7, 1812. Several thousand additional “smaller” earthquakes occurred during the three month period from Dec. 16, 1811 to March 16, 1812. Due to the harder, colder, drier and less fractured nature of the rocks in the earth’s crust in the central United States, earthquakes in this region can shake and damage an area approximately 20 times larger than earthquakes in California and most other active seismic areas. The frequency of large earthquakes in the zone is still being debated, but the New Madrid Fault appears to be about 30 years overdue for a magnitude 6.3 quake because the last quake of this size occurred one hundred years ago at Charleston, Missouri, on Oct. 31, 1895 (a magnitude 6.7). A magnitude 6.3 quake near Lepanto, Arkansas, on Jan. 5, 1843, was the next earthquake of this