Earthquakes stir fear in America's Heartland as deadly fault zone awakens

A giant seismic zone in the heart of the US has seen dozens of tiny earthquakes break out in the last month, renewing fears of a catastrophic natural disaster soon.

Since mid-November, the US Geological Survey (USGS) has detected at least 38 low-level seismic events along the boundaries of the New Madrid Seismic Zone (NMSZ) in Arkansas, Kentucky, Missouri, and Tennessee.

The NMSZ is a large area in the middle of the US where hundreds of minor earthquakes have been recorded each year, with these light tremors being considered harmless and normal for the region.

None of the new quakes registered greater than 2.6 in magnitude, meaning it's unlikely residents felt them, but the fresh activity came almost exactly on the date and in the same location as the last major seismic event to erupt within the NMSZ.

The latest tiny tremor, a magnitude 1.8 quake, was recorded on December 15, just one day before the 214th anniversary of the devastating 1811-1812 earthquake swarm.

Between December 1811 and February 1812, a group of three powerful quakes over 7.0 in magnitude caused damage in cities such as Cincinnati and St Louis and was felt in states as far away as Connecticut and Louisiana. 

Scientists have found that large quakes like these could happen in the NMSZ every 200 to 800 years, meaning the region is now well within the range for the next major disaster in the Midwest.

While the latest swarm this month falls within the range of normal seismic activity along the NMSZ, researchers still don't know the exact reason giant earthquakes even form here or when the next one will strike.

The NMSZ stretches about 150 miles along the Mississippi River Valley, covering parts of northeastern Arkansas, southeastern Missouri, western Tennessee, western Kentucky, and southern Illinois.

This zone is one of the most active earthquake spots east of the Rocky Mountains, even though it's relatively unknown compared to earthquake hotspots such as Southern California and the Bay Area.

Researchers with the USGS have warned that this strange area has a 40 percent chance of unleashing a magnitude 6.0 earthquake within the next five decades.

Despite the risk, the NMSZ has remained a geological oddity because it's an intraplate seismic zone, meaning it's far from tectonic plate boundaries that typically cause earthquakes as they grind past each other.

Conversely, the New Madrid zone sits in the middle of the stable North American plate, on an old buried weak point that's somehow still seismically active.

Eric Sandvol, a professor of geological sciences at the University of Missouri, told the Daily Mail in 2024: 'So how is it that we have earthquakes there? A partial answer to that is, we're not really sure. There's a lot we don't understand about it.' 

As tiny earthquakes continue to fill the zone, both state and federal officials have already begun preparing for a catastrophic disaster that rivals the 1811-1812 swarm.

A 2025 blog post on the Geological Society of America's official site warned that a magnitude 7.6 earthquake could cause more than $43 billion in damage, while previous studies have estimated the potential death toll at more than 80,000.

In 2019, USGS scientists modeled what a 7.7 magnitude earthquake would look like if it erupted along the Arkansas-Tennessee border, in an area near Memphis.

The shockwaves of this hypothetical mega quake spread for hundreds of miles, reaching cities including Kansas City, Indianapolis, Louisville, and Birmingham.

Since this region is not well equipped to deal with a massive seismic event, studies of such an earthquake projected that a magnitude 7.7 earthquake would cause over 86,000 injuries or deaths, damage 715,000 buildings, and knock out power to 2.6 million homes.

That report, by the University of Illinois, Virginia Tech, and George Washington University, also estimated that the cost could hit $300 billion directly, with indirect costs due to lost jobs possibly taking the damage to $600 billion.

Unlike California, which builds its buildings specifically to withstand the stress of seismic activity, experts have noted that states like Arkansas, Kentucky, Missouri, and Tennessee do not.

Danielle Peltier, a science communication fellow with the Geological Society of America, said: 'Midwestern infrastructure and architecture are designed with more frequent natural hazards, like tornadoes, in mind.'

'This means a magnitude 6 quake can have a greater impact in Missouri than somewhere like California.'