(AP) An earthquake centered in southern Illinois rocked people awake across the Midwest early Friday, surprising residents unaccustomed to such seismic activity.
The quake just before 4:37 a.m. was centered 6 miles from West Salem, Ill., and 66 miles west of Evansville, Ind.
Initially pegged as a 5.4 earthquake, the U.S. Geological Survey revised its estimate to give it a value of 5.2.
West Salem is in Edwards County, and dispatcher Lucas Griswold says the sheriff's department received several calls about the earthquake but only reports of minor damage and no injuries.
"Oh, yeah, I felt it. It was interesting," Griswold said. "A lot of shaking."
In Mount Carmel, 15 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.
The quake shook skyscrapers in Chicago's Loop, 230 miles north of the epicenter, and in downtown Indianapolis, about 160 miles northeast of the epicenter.
U.S. Geological Survey scientists in Denver were examining data about the quake, said geophysicist Carrieann Bedwell.
"This was widely felt, all the way to Atlanta, a little bit in Michigan," she said.
Residents in Milwaukee, Cincinnati, Louisville and St. Louis also reported feeling the earth shake.
"It shook our house where it woke me up," said David Behm of Philo, 10 miles 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."
Phones started ringing at the Crawford County Sheriff's Department in Robinson, about 15 miles north of the epicenter, but there were no immediate reports of damage, dispatcher Marsha Craven said.
"They didn't know if it was the refinery blowing up or an earthquake," she said, referring to the a local petroleum refinery.
Craven said she's lived in the area her whole life, and felt a handful of earthquakes, but couldn't recall one this big.
In Cincinnati, one woman said she felt something that lasted for up to 20 seconds.
"All of a sudden, I was awakened by this rumbling shaking," said Irvetta McMurtry, 43. "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."
Johna Todd, a dispatcher at the Edgar County Sheriff's Department in eastern Illinois, said the quake rattled the area and led to numerous 911 calls, but all to ask why their homes were shaking rather than report damage.
In Frankfort, Ky., Ray Teron was awakened by the quake. But he said his mother, whom he lives with, slept through it.
"It definitely rattled the dishes. It was enough to wake you up."
The Midwest, most notably southeast Missouri and southwest Illinois, is home to the New Madrid fault, a network of deep cracks in the earth's surface.
The fault, at the center of the country's most active seismic zone east of the Rockies, produces numerous small quakes a year, most too weak to be noticed by the public.
But in 1811 and 1812, it produced a series of earthquakes estimated at magnitude 7.0 or greater. It was not immediately clear Friday if the fault extends as far east as West Salem.
Even before Friday, earthquakes - or the possibility of them - in the central U.S. were getting plenty of attention.
Early next month, agriculture extension officials from various regional states already are scheduled to convene an earthquake summit, hosted by the University of Illinois' extension service.
Planners of the New Madrid Earthquake Emergency Preparedness Conference in the Ohio River community of Metropolis, Ill. say representatives from Illinois, Arkansas, Indiana, Missouri and Tennessee are to attend.
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