The second earthquake in almost two months happened in Michigan on Tuesday.

The 3.3 magnitude quake occurred around 11:42a.m., in rural Calhoun County, near Tekonsha, about 20 miles from the epicenter of the May earthquake in Kalamazoo County.

Scientists from Western Michigan University and the U.S. Geological Survey say the quake is not related to fracking, MLive Media Group/ The Grand Rapids Press reports. 

Christopher Schmidt, WMU Professor Emeritus of Geosciences said,

"No, no, no. There is no chance in the world of that. There is no fracking in that area and no deep disposal wells. There's zero chance it's related to fracking."

 

Hydraulic fracturing (fracking) is the process of using water pressure to create fractures in rock that cause the oil or gas to flow more freely.

While scientists have connected fracking to seismic activity in some states, Don Blakeman, a geophysicist with the U.S Geological Survey said that Tuesday's tremor is unlikely related to fracking.

So what did cause the Michigan earthquakes?

According to MLive, Both Blakeman and Schmidt said that both quakes are a part of a fault system that caused a 4.6 magnitude quake in Coldwater in 1947, the largest ever recorded in Michigan.

Schmidt said, "Probably the strain that resulted in the (May 2) quake wasn't all released," which caused Tuesday's quake.