GREELEY, Colo. — After a 3.4-magnitude earthquake struck near Greeley late last month, some graduate students and a professor from the University of Colorado have undertaken a study to determine if there is a connection to oil and gas drilling.

The epicenter of the quake is close to wastewater injection wells in the area, which hasn’t had earthquake activity in about three decades, the Greeley Tribune reported.

CU geophysics professor Anne Sheehan and the students have added seismographs near where the U.S. Geological Survey says was the epicenter, about 4 miles northeast of Greeley. The estimated epicenter isn’t precise because the nearest station to record tectonic activity is in Idaho Springs.

“I guess we wouldn’t have done this if we didn’t think there would be some small follow-up earthquakes,” Sheehan told the Tribune. “It’s possible we won’t record anything of interest. One would hope there would not be any more earthquakes. But if there are, we will study them.”

An uptick of drilling in Ohio, Oklahoma and Texas has also brought more tectonic activity, with it being linked to oil and gas wastewater disposal wells. There are 28 oil and gas waste disposal wells in Weld County, with two of them near the epicenter of the May quake.

“If we find out something useful about whether injection causes earthquakes, it might be something that the industry can use to do a better job of injecting, if that turns out to be a problem,” Sheehan said. “So maybe if they inject at lower volumes or spread it out more, it could be that there are things that we’ll learn that can help inform some sort of best practices.”