The tremblor, centered in West Liberty, about 15 miles east-southeast of Kokomo, was felt more than 100 miles away.
Howard County Sheriff Marty Talbert said 113 people called 911 in a 15-minute period after the quake, which was the first tremblor centered in Indiana since 2004.
There were no substantiated reports of damage or injuries from the quake.
“It was a grinding noise, and it sounded like it was going along the side of my house,” Kokomo homeowner Ethel Brown said. “Then I heard a loud bang, and it was over.”
Julie Dutton, a geophysicist with the U.S. Geological Survey in Golden, Colo., said the quake lasted about 10 seconds, and probably wasn’t strong enough to do much damage.
“It was a considered a minor earthquake,” she said. “Maybe some things would be knocked off shelves, but as far as some significant damage, you probably wouldn’t expect it from a 3.8.”
USGS officials estimate the actual impact radius was probably somewhere between 120 and 190 miles.
The quake was centered in some eastern Howard County farm fields, with 1250 East and Ind. 26 being the closest major intersection. It was about five miles south of Greentown, and roughly halfway between Phlox and Point Isabel on the map.
Dutton said it was the same magnitude on the Richter scale as the Sept. 12, 2004, earthquake centered in Shelby County, southeast of Indianapolis, about 57 miles from Kokomo.
Howard County residents also felt an earthquake on April 18, 2008, a 5.2-magnitude quake centered in Illinois.
There is no known major fault line where Thursday’s earthquake occurred, which isn’t unusual, Dutton said.
“There are fault lines all throughout the eastern United States, and a lot of earthquakes happen along fault lines we’ll never know about,” she said. “It’s hard to map things that don’t occur very often.”