There have been enough earthquakes in the past year for geologists to take a closer look at a possible cause.

Experts plan to place more monitors near Greers Ferry Lake between Clinton and Heber Springs after a recent jump in quakes, including one late last month in Clinton that registered a 2.1 magnitude.

Scott Ausbrooks of the Arkansas Geological Survey said recently that most of the quakes have been too minor to feel, but he hopes to pinpoint a reason for the increase.

One possible cause of the quakes could be water-level changes in Greers Ferry Lake, he said.

He said it is too early to tell if natural gas injection wells in the area could be a contributor to the quakes. After hundreds of quakes in Faulkner County in the area of injection wells, the state Oil and Gas Commission banned such wells within a 1,150-square mile area. That banned area did not reach to Van Buren County.

Injection wells are used to dispose of wastewater from hydraulic fracturing deep into the earth.