ST. LOUIS - With two earthquakes striking Tennessee Wednesday many are wondering if a big one will hit St. Louis.
Experts say it's not a matter of if one will hit, it's a matter of when.
Seismologists estimate a 25 to 40 percent chance of a major earthquake in the "New Madrid Seismic Zone" within the next 50 years.
It would affect an estimated 11 million people and more than half-dozen states that border the Mississippi River including Missouri and Illinois.
Depending on the strength of the earthquake, experts say St. Louis could be severely damaged while Memphis could be wiped out. The St. Louis area has experienced minor earthquake damage at least 12 times in the past 205 years.
The ground could even liquify and turn to mud which is what happened more than a hundred years ago during "The Great Earthquake of New Madrid" in Missouri bootheel.