LILBOURN, Mo. – Three earthquakes shook the southeast Missouri town of Lilbourn during an hour this morning. The USGS report that the first quake was at 11:18am with the second following at 11:29am and the third at 11:57am. They were all based at around 2-3 miles west to southwest of town and 5 miles deep. The magnitues of the quakes range from 2.6 to 2.7 on the Richter scale.
FOX 2 reported several other quakes this month. The closest to St. Louis was recorded in St. Francois County on September 11, 2019. That 2.6 magnitude quake was nearest to Bonne Terre and Valles Mines.
A 3.7 magnitude quake shook the Missouri and Arkansas border on September 12 and was felt by some in the St. Louis area.
Bob Herrmann, a professor of geophysics at Saint Louis University, tells FOX 2 that earthquake activity isn’t increasing in our area. He said it’s actually been quiet and the last big shaker was in April 2008 in southeast Illinois.
Earthquakes of magnitude 3.0 and up are widely felt. At magnitude 5.0, buildings will begin to see damage; but it depends on how close the buildings are to the quake’s epicenter. The last big quake in April 2008 had a magnitude of about 5.3 and damaged some buildings.
Earthquakes are not uncommon in the New Madrid Seismic zone. It is the most seismically active places in North America east of the Rockies. During the winter of 1811-1812 three very large earthquakes devastated the area. About twice a year people feel still smaller earthquakes that do not cause damage.