HENNESSEY, Okla. (AP) - A series of small to moderate earthquakes have struck in central Oklahoma.
The U.S. Geological Survey has recorded eight quakes since Tuesday near Hennessey, about 45 miles (72 kilometers) northwest of Oklahoma City.
The most recent quake occurred at 2:54 p.m. Wednesday with a preliminary magnitude of 3.4 after a magnitude 3.1 quake struck nearly eight hours earlier. The largest quake - a magnitude 4.1 - struck at 4:50 a.m. Tuesday, the same day five temblors of magnitude 3.0 or below were recorded in the area.
No injury or damage is reported.
Thousands of quakes have struck Oklahoma in recent years, many linked to the underground injection of wastewater from oil and natural gas production. Some oil and gas producers have been directed to close some wells and reduce injection volumes in others.