DETROIT – A 3.6 magnitude earthquake was felt Thursday night in parts of southeastern Michigan and southwestern Ontario, Canada.
The earthquake hit near Amherstburg, Ontario, at 8:01 p.m. and was felt across the Metro Detroit area, especially Downriver. No injuries were reported.
Scientists from the University of Michigan's Department of Earth and Environmental Sciences said these quakes are rare but not unheard of in the region.
"Earthquakes in and near the Lower Peninsula of Michigan are rare but not unheard of. The seismicity in the area north of Lake Erie is lower than the area to the south of the lake or in western New York state," said Eric Hetland said a geophysicist and associate professor at the University of Michigan. "Michigan is basically a big bathtub filled with sediments, which is the reason it has fewer earthquakes than surrounding regions."
Scientists said the earthquake is the most significant earthquake in the region since a pair of Michigan quakes in May and June of 2015. The quake in May 2015 had a magnitude of about 4.2.
"This earthquake is unusual. It is the most significant earthquake in this area since the pair of Michigan events back in May and June of 2015," said University of Michigan professor Larry Ruff. "A magnitude-4.2 earthquake hit near Galesburg in Kalamazoo County in May 2015, and was followed the next month by a smaller one. The May 2015 earthquake near Galesburg was the largest quake in Michigan since 1947 and the second-largest in records dating back roughly a century."
This seismicity map shows all earthquakes in the region with a magnitude of 3.2 or larger since 1971.
Yihe Huang, an assistant professor in the Department of Earth and Environmental Sciences who studies the physical mechanisms of earthquakes and faulting processes, said there have been several fairly small earthquakes around Lake Erie in the past couple years that were likely not felt by area residents.
"There was a magnitude-2.6 earthquake north of Lake Erie in 2017 and a magnitude-2.5 earthquake west of Lake Erie in 2016," she said. "Some more comparable earthquakes include a magnitude-3.2 earthquake south of Lake Erie in 2013 and a magnitude-3.0 earthquake south of it in 2010."
Again, no injuries were reported. Personal injury from these quakes are very rare, scientists said, but damage is possible.
"Some nearby damage is possible when they are shallow in origin, like this one," said Ben van der Pluijm, an earthquake geologist and professor at the University of Michigan. "Because of the strong bedrock, they are felt over a much wider region than similar-sized quakes on the East Coast."
This seismogram of the April 19, 2018, earthquake was recorded at the Ann Arbor seismograph station.
USGS classifies quake intensity as 'IV"
Meteorologist Ben Bailey explained the USGS (United States Geological Survey) classified this earthquake as a IV (four) "light" quake on an intensity scale.
"They base that (intensity) rating on what people feel. They wait for the reports to come in and this is how they decide what the intensity was. It was moderate shaking and a four -- damage potential none," said Bailey.
The 3.6 magnitude rating is from a different scale, Bailey explained.
"That's what we used to call the Richter (magnitude) scale," he said.
Watch Bailey's explanation here.
Metro Detroiters feel shaking
Practice Thursday night for the St. James Episcopal Church choir in Grosse Ile was interrupted by the quake. Choir members were wondering if it was the church's boiler, or a meteor, or worse.
They reported feeling a 30-second shake. The church is about 4 miles from the epicenter of the quake in Amherstburg.
Grace Lyon, 12, was at softball practice when the ground started shaking.
"I got scared, and I kind of freaked out on the inside but I couldn't show it because the ball was being thrown to me as it happened," she said.
She made the play anyway.
There were no reports of damage.