Earthquake at Tennessee Warns of Risks of Intense Quakes in the Region

A 2.6-magnitude mild earthquake struck the region outside Knoxville, Tennessee during the night, Weatherboy reports.

According to the USGS, the earthquake occurred at a depth of 9 km from the town of Garland in the eastern part of the state. This event is the strongest earthquake recorded in Tennessee this month.

In the past week, the state has been hit by three earthquakes: a magnitude 2.1 quake near Ridgely and a magnitude 2.0 and 1.6 quakes near Tiptonville.

Earthquakes have also been felt near the state of Missouri, Georgia, and Arkansas in the past couple of weeks. While these earthquakes are mild and scattered across Tennessee, scientists are advising people to prepare in case something much stronger occurs.

While many people associate earthquakes with the western states rather than Tennessee, one of the strongest earthquakes in the United States occurred not far away. And scientists are concerned that residents of this region are not properly prepared for the next major earthquake to hit the area.

New Madrid Seismic Zone

On December 16, 1811, at about 2:15 a.m., an 8.1 magnitude earthquake rocked northeast Arkansas in what is now known as the New Madrid seismic zone. The quake was felt throughout much of the eastern United States and jolted people out of bed in places like New York City, Washington, DC, and Charleston, SC.

In areas that were particularly hard hit by the earthquake, such as Nashville, TN, and Louisville, KY, the ground shook for an incredibly long time, running from 1 to 3 minutes.

Ground motions were so violent near the epicenter that liquefaction of the ground was observed, with soil and water being thrown several feet into the air.

President James Madison and his wife Dolly felt the quake in the White House. Tremors were felt across Boston where church bells rang.

From December 16, 1811, to March 1812, more than 2,000 earthquakes were reported in the Midwest, including 6,000-10,000 earthquakes located in the "Bootheel" where the New Madrid seismic zone is located.

The second main shaking, a magnitude 7.8, occurred weeks later on January 23, 1812, in Missouri. The third, a magnitude 8.8, occurred on February 7, 1812, along the Reelfoot fault in Missouri and Tennessee.

The main earthquakes and the violent aftershocks caused considerable damage and claimed some lives. However, the lack of scientific tools and the poor news coverage of the time were unable to capture the full extent of the events.

Earthquake Lights

In addition to the tremors, the earthquakes were also responsible for triggering unusual natural phenomena in the area, which include earthquake lights, seismically heated water, and earthquake smog.

Residents in the Mississippi Valley reported seeing lights flashing from the ground.

Scientists believe this phenomenon is "seismoluminescence", which is light produced when quartz crystals in the ground are compressed. The "earthquake lights" were triggered during the main earthquakes and strong aftershocks.

The water is thrown into the air from the ground, and the nearby Mississippi River was also unusually warm. Scientists speculate that the strong vibrations and resulting friction caused the water to heat up.

Other scientists believe that the light emitted by the quartz crystals as they were squeezed, also contributed to the heating of the water.

Read also: A 5.5 Magnitude Earthquake Shakes Area Near the Fukushima Disaster Site 

During the strong quakes, the sky darkened so much that residents claimed the lights did not illuminate the area; they also said the air smelled bad and was difficult to breathe.

Scientists suspect that this "earthquake smog" was caused by dust particles rising from the surface and combining with the eruption of warm water molecules in the cold winter air. The result was a steaming, dusty cloud that enveloped the areas affected by the quake.

The area remains seismically active, and scientists believe the region will be hit again by a strong earthquake sometime in the future. Unfortunately, science is not yet mature enough to say whether this threat will occur as early as next week or as late as 50 years from now.

Either way, because the population of the New Madrid Seismic Zone is huge compared to the sparsely populated area in the early 1800s, and millions more people live in an area that will be affected by strong ground shaking, there could be a significant loss of life and property if another major quake occurs.

Related article: Experts are Studying the "Biggest Earthquake in Human History"