Eleven earthquakes have been recorded in Van Buren and Cleburne counties since May 16, 2014, according to information from the Arkansas Geological Survey.
Seven of those earthquakes were in Fairfield Bay, two in Clinton and two in Heber Springs.
The strongest of the quakes was a 3.8 magnitude that occurred June 4 at 4:20 p.m.
The other quakes ranged from 1.6 to 2.2 magnitude. The most recent quakes occured June 9.
Several residents posted on social media that they had felt some of the quakes.
In 2010, the Guy-Greenbrier area in Faulkner County experienced a swarm of earthquakes. The largest of those was a 4.7 magnitude. After the Arkansas Oil and Gas Commission voted unanimously to ban injection disposal wells in the area the number of earthquakes soon declined.
At least three gas companies were injecting fracking wastewater in the area where more than 1,200 earthquakes occurred in Faulkner County. The area is near an active fault.
Fracking, or hydraulic fracturing, is a controversial gas drilling method that involves pumping water and chemicals deep underground to break up rock and free natural gas. Fracking produces millions of gallons of wastewater.
Van Buren County is home to many gas wells and drilling operations.