Below the Din

This morning, an earthquake measuring 5.4 on the Richter Scale shook southern Illinois. The area is no stranger to quakes, being part of the New Madrid fault zone. The following is an article I wrote in 2001 following a 6.8-magnitude quake that shook Seattle.

Last Wednesday, an earthquake measuring 6.8 on the Richter scale gave Seattle residents an afternoon they will remember for quite a while. Miraculously, there were relatively few injuries and no fatalities. The region lies on an active fault line, and while the Seattle area is not unfamiliar with quakes, it caught more than a few by surprise. Travel southeast across two time zones to New Madrid, MO, the namesake of the New Madrid Seismic Zone. The area is roughly 500 miles due south of McDonough County. The fault lies almost halfway between St. Louis and Memphis, was the site of one of the most intense earthquakes in North American history.

It was not just one earthquake that rocked the lower Mississippi River valley. The Center for Earthquake Studies at Southeast Missouri University website reports that there were 2000 measurable shocks over a five month period. Five separate times the Richter scale topped 8.0–hundreds of times stronger than the 7.0 San Francisco “World Series” earthquake of 1989–and eighteen times Missouri quakes rang church bells on the eastern seaboard. Buildings in the city of Boston were damaged, 1000 miles away from the epicenter. Survivors told of the ground rolling in waves, the destruction of New Madrid, the creation of Reelfoot Lake, and change of course of one of the world’s longest rivers.

A magnitude-8 earthquake may not recur for a few hundred years, but the chances of a 6.0 or higher earthquake happening in the first half of the 21st century is great. The Center for Earthquake Research and Information at the University of Memphis states a major quake affecting the Missouri/Illinois area is likely to happen. Researchers say within 15 years there is a 40 to 60 percent chance of an earthquake measuring roughly 6.3, and an 86 to 97 percent chance of one within the next 50 years. If a 6.0 earthquake were to occur as predicted, geological differences between the land east and west of the Rocky Mountains would cause more damage in Missouri than it would in California.

Like all natural disasters, there are several myths and misconceptions surrounding earthquakes. The ground does not open up, swallowing everything standing over it, according to CERI. The ground can, however, cause several shallow crevices, but there was “no reliable account” of anyone falling to their death. Another myth states that a major earthquake cannot occur in a region that has several smaller earthquakes—those little quakes could be a precursor to a major event.

CERI recommends that all family members know how to turn off the gas, water and electricity. Heavy objects such as bookcases, entertainment centers, mirrors, and cabinets should be anchored to walls whenever possible. Never place heavy objects over beds, and should be kept lower than the head height of the shortest member of the family.

Illinois Transportation Secretary Kirk Brown announced the 2001 Earthquake Response Conference for April 18-19 in Carbondale. The two-day conference will include a simulated earthquake to test the state’s emergency response. The Illinois Department of Transportation has an Earthquake Preparedness Plan and conducts exercises to test its procedures to ensure the department is ready to respond.

For more information regarding the New Madrid Seismic Zone, the New Madrid Earthquakes of 1811-12, or Earthquake safety, visit www.cusec.org, www.semo.edu/ces/, and www.ceri.memphis.edu.