Clarksville, TN – With the recent 5.8 magnitude earthquake in Virginia, the time is right to remind people that Clarksville, Tennessee lays in the destructive damage footprint of a large earthquake on the New Madrid Fault line.
The New Madrid Seismic Zone (NMSZ) is located in southeastern Missouri, northeastern Arkansas, western Tennessee, western Kentucky and southern Illinois. It is the most active seismic area in the United States east of the Rocky Mountains.
The history of earthquakes in northeastern Arkansas and the surrounding region that covers the New Madrid Seismic Zone (NMSZ) is significant. On December 16th, 1811, a magnitude-7+ earthquake struck what is now Memphis, Tennessee. This was the first in a series of quakes that caused strong shaking over a broad region and resulted in widespread eruptions of water and sand, triggered landslides, and lifted up and dropped down large areas by the time the final quake occurred on February 7th, 1812 in New Madrid, MO. Since then, the regions along the NMSZ have experienced explosive growth in both population and infrastructure. Another series of earthquakes with the magnitude of the 1811 earthquakes could prove catastrophic to the region.
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 shake and damage an area approximately 20 times larger than earthquakes in California and most other active seismic areas. Even though large earthquakes occur much less frequently in the NMSZ than in California, the long term average quake threat, in terms of square miles affected per century, is about the same because of the approximately 20 times larger area affected in the central United States.
The NMSZ appears to be about 30 years overdue for a magnitude 6.3 quake because the last quake of this size occurred 100 hundred years ago at Charleston, Missouri, on October 31st, 1895 (it was a magnitude 6.7). A magnitude 6.3 quake near Lepanto, Arkansas, on January 5th, 1843, was the next prior earthquake of this magnitude. About 75 percent of the estimated recurrence time for a magnitude 7.6 earthquake has elapsed since the last quake of this size occurred in 1812.
To help ensure that residents are prepared for a large earthquake, FEMA encourages the following:
- Get a Kit – Get an Emergency Supply Kit, which includes items such as non-perishable food, water, a battery-powered or hand-crank radio, extra flashlights and batteries. You may want to also prepare a portable kit and keep it in your car.
- Make a Plan – Your family may not be together when disaster strikes, so it is important to know how you will contact one another, how you will get back together, and what you will do in case of emergency.
- Prepare Your Business – The FEMA/Federal Insurance and Mitigation Administration (FIMA) QuakeSmart Web site provides tips for how mitigation can reduce business risks.
- Help Your Community Prepare – Inquire about emergency plans at places where your family spends time: work, daycare, and school. If no plans exist, consider volunteering to help create one.
- Sharpen Your Skills – Take a Community Emergency Response Team (CERT) class from your local Citizen Corps charter. Keep your training current.
- Plan for Cover – Identify safe places indoors and outdoors where you could take cover, such as under sturdy furniture or against an inside wall without any glass that could shatter or heavy bookcases that could fall over.
The intensity map for one of the quakes from the 1811-1812 series of earthquakes. Clarksville Tennessee would be in the zone for destructive damage.