Magnitude 5.2 Earthquake Rattles U.S. Midwest

Jim Suhr in West Salem, Illinois
Associated Press

April 18, 2008

Residents across the U.S. Midwest were awakened this morning by a magnitude 5.2 earthquake that appears to have caused no major injuries or damages.

Two aftershocks during the next three hours measured magnitude 2.6 and 2.5.

The quake, which struck just before 4:37 a.m. local time, was centered 6 miles (9.6 kilometers) from West Salem, Illinois.

It rattled skyscrapers in Chicago and homes in Cincinnati, Ohio, and was even felt as far away as Des Moines, Iowa, and Atlanta, Georgia.

"It shook our house where it woke me up," said David Behm of Philo, Illinois, 10 miles (16 kilometers) south of Champaign.

"Windows were rattling, and you could hear it. The house was shaking inches. For people in central Illinois, this is a big deal. It's not like California."

Distant Shaking

In Mount Carmel, 15 miles (24 kilometers) southeast of the epicenter, a woman was trapped in her home by a collapsed porch but was quickly freed and wasn't hurt, said Mickie Smith, a dispatcher at the police department.

The department took numerous other calls, though none reported anything more serious than objects knocked off walls and out of shelves, she said.

Lucas Griswold, a dispatcher in West Salem, said the Edwards County sheriff's department received reports of minor damage and no injuries.

"Oh, yeah, I felt it. It was interesting," Griswold said. "A lot of shaking."

Cincinnati resident Irvetta McMurtry said she felt the rattling for up to 20 seconds.

"All of a sudden, I was awakened by this rumbling shaking," McMurtry said.

"My bed is an older wood frame bed, so the bed started to creak and shake, and it was almost like somebody was taking my mattress and moving it back and forth."

In Louisville, Kentucky, the quake caused some bricks to fall off a building near downtown. Television video showed the bricks strewn in the street.

The quake also shook skyscrapers in downtown Indianapolis, about 160 miles (257 kilometers) northeast of the epicenter.

New Madrid Zone

Today's quake is believed to have involved the Wabash fault, a northern extension of the New Madrid fault that creates a seismic zone in the Midwest, said U.S. Geological Survey geophysicist Randy Baldwin. (Get an overview of plate tectonics.)

In 1811 and 1812, the New Madrid fault produced a series of earthquakes estimated at magnitude 7.0 or greater said to be felt as far away as Boston, Massachusetts.

Experts say that with the much higher population in the Midwest, another major quake along the New Madrid fault zone could destroy buildings, bridges, roads and other infrastructure, disrupt communications, and isolate areas.

(Read "Big Earthquake Could Devastate U.S. Midwest, Experts Warn" [April 12, 2006].)

The last earthquake in the Wabash region to approach the severity of today's temblor was a magnitude 5.0 quake that shook a nearby area in 2002, Baldwin said.

"This is a fairly large quake for this region," he said. "They might occur every few years."

The strongest earthquake on record with an epicenter in Illinois occurred in 1968, when a magnitude 5.3 temblor was recorded about 75 miles (120 kilometers) southeast of St. Louis, according the USGS.

The damage from that event was minor but widespread and there were no serious injuries.