J. David Rogers, professor of geological engineering at Missouri University of Science and Technology, said the Wabash Valley Seismic Zone is "definitely capable of spawning 7.0 magnitude earthquakes approximately every 1,000 years. We know there was a large event about 4,600 years ago -- a magnitude 7 or above."

There also were large ones in 1891, 1968 and 1987.

"This zone has been crackin' off magnitude 5-plus events, and quite a few historic ones," Rogers said. The Missouri University of Science and Technology is based in Rolla.

One problem is that the federal or state governments haven't pumped money into research in the Wabash Valley zone like they have for the New Madrid quake zone. For example, the New Madrid zone has 13 seismographs.

"We don't even have a single seismograph in the Wabash Valley zone," he said. "We haven't spent the money looking up there as in the New Madrid zone."

That means that the shock waves for that quake were measured using instruments 100 or more miles away, in places like St. Louis, New Madrid and Kentucky.

"We're missing how much amplification you're getting at the epicenter. It's not going to tell you the severity of the shaking on the earth's surface," he said.

The 1968 quake, with its epicenter near Dale, Ill., was about 35 miles from the Wabash River. It measured a 5.3 magnitude. In June 1987, a 5.0 magnitude quake was centered in Olney, Ill., just north of today's earthquake.

Rogers said a 5.2 quake, which today's was, might cause shaking for 10 seconds and shouldn't cause a whole lot of damage.

"It might knock down a few chimneys, but we don't expect it to cause gross structural damage," Rogers said.

Via St. Louis Post-Dispatch.