The U.S. Geological Survey has recorded a preliminary magnitude-3.1 earthquake near Greenbrier in central Arkansas.

The quake was recorded at 7:20 a.m. Saturday three miles northeast of Greenbrier - about 35 miles north of Little Rock. Greenbrier police say there weren't any reports of injuries or damage. A magnitude-2.2 quake was recorded in the same area 20 minutes later.

Seismologists have recorded some 1,000 quakes in the region since September - including a magnitude 4.7 in February that was the strongest earthquake recorded in Arkansas in 35 years.

The latest quakes come after two natural gas exploration companies - Oklahoma City-based Chesapeake Energy Corp. and Clarita Operating LLC - agreed this week to keep two nearby injection wells shutdown as researchers study whether the operations are linked to the quakes.

Source: The Associated Press