A swarm of earthquakes hit a massive 150-foot-long fault line in the Midwest that scientists fear is overdue for a mega-quake.
This little-known New Madrid sits in America’s Heartland, passing through Missouri, Arkansas, Tennessee, Kentucky and Illinois.
The US Geological Survey detected eight quakes from December 6 to 11.
Missouri experienced seven that hit Howardville, Matthews, Martson Hayward and Cooter, and Ridgely, Tennessee experienced one.
The largest quakes were a magnitude 3.0 and 2.6 that struck near Howardville, and the rest measured roughly magnitude 2.
Any earthquake less than magnitude 2.5 generally isn’t felt, but the shaking can be detected by a seismograph.
Scientists have warned that the fault line can generate a magnitude 7 or higher in the next 50 years.
The likelihood of a earthquake of that size is approximately 40 percent, but according to Robbie Myers, an emergency coordinator with the Missouri Department of Safety, the probability increases with each passing year.
Approximately seven of the quakes rocked the region within a nine-hour span, with the 3.0-maginuted at 6:27am ET.
And on December 11, the eight was detected in Howardville.
The area has not had a significant quake in more than 200 years.
According to the U.S. Geological Survey, the most recent significant seismic activity took place between 1811 and 1812 when three earthquakes struck, with magnitudes estimated to be between 7 and 8.
The swarm destroyed settlements and ‘dramatically affected the landscape,’ officials reported.
While the recent earthquake swarm does not necessarily indicate an impending larger earthquake along the New Madrid fault line, experts advise residents living in the vicinity to always be prepared for a major seismic event.
A magnitude 8 quake in this region could kill thousands, destroy bridges over the Mississippi River, buckle major highways such as Interstate 55 and cause oil and gas pipelines to break, Myers previously told DailyMail.com.
Experts believe the most significant destruction would occur in St Louis, Missouri, and Memphis, Tennessee. But an event of this magnitude would cause nationwide disruptions.
A damaging earthquake of magnitude 6 or greater occurs about once every 80 years in the New Madrid Seismic Zone (NMSZ), according to the United States Geological Survey (USGS).
The last one of that magnitude was a 6.6 event in 1895 near Charleston, Missouri – 129 years ago. Thus, this fault is long overdue for a large earthquake.
‘[An earthquake] in the next 50 years is a strong possibility, and people should take precautions,’ Myers said.
‘Right now there is nothing more pressing. And every year that goes by, the likelihood becomes greater.’
The 150-mile-long New Madrid Seismic Zone (NMSZ), which stretches through parts of Missouri , Arkansas , Tennessee , Kentucky and Illinois, has an up to 40 percent chance of a magnitude 6 or higher quake occurring in the next 50 years
At least 11 million Americans live within the danger zone, with the most significant destruction predicted to occur in St Louis and Memphis, an expert previously told DailyMail.com
The NMSZ is one of the most active seismic zones east of the Rocky Mountains. Thus, swarms like Monday’s are not uncommon.
Earthquake swarms are characterized by clusters of small to moderate quakes that occur over a short period.
Scientists are still investigating what causes an earthquake swarm, but they have some theories.
One possible explanation is that the fault is slipping slowly, and small sticky patches are popping off and generating numerous small earthquakes, according to the USGS.
Alternatively, magma – or molten rock – might be pushing up into the Earth’s crust, opening a pathway for itself by breaking the rock in front of it and triggering a series of quakes.
But most often, earthquake swarms appear to be caused by the gradual release of tectonic stress along fault lines, or changes in subsurface conditions, according to the USGS.
Although the NMSZ frequently produces earthquakes, their generally low magnitude and meager impact doesn’t garner much attention for this seismic zone.
Instead, most of the earthquake preparation in the US has focused on California, which experts say is about 80 years overdue for ‘The Big One’, a massive earthquake along the 800-mile long San Andreas fault.
This focus on California has made it harder for experts in Missouri and other states on the NMSZ to convince officials and the public to be prepared.
But the impact of an earthquake in this area could be more widespread than what’s recorded on the West Coast, the Missouri Department of Natural Resources has said.
‘Due to the nature of the bedrock in the earth’s crust in the central United States, earthquakes in this region can shake an area approximately 20 times larger than earthquakes in California,’ Department officials wrote in a blog post.