A swarm of earthquakes struck central Oklahoma Saturday and early Sunday, producing the state's strongest quakes so far in 2014, according to the U.S. Geological Survey.
The primary swarm of earthquakes was centered in northwestern Logan County and northeastern Kingfisher County, about 12 miles north of Crescent.
In that cluster, the USGS recorded nine earthquakes ranging in magnitude from 2.6 to 4.3 between 10 p.m. CDT Saturday and 7 a.m. Sunday. The two earthquakes measuring 4.3 on the moment magnitude scale were the strongest earthquakes so far in 2014 in Oklahoma, eclipsing a 4.1 jolt centered near Langston on Feb. 8.
The pair of magnitude-4.3 tremors, which occurred at 1:51 a.m. and 3:42 a.m. CDT Sunday respectively, were both felt across a wide area. The "Did You Feel It?" section of the USGS website received reports of shaking as far north as the Kansas City metropolitan area and as far south as Norman, Okla., from both earthquakes. Vibrations were also felt as far east as the Tulsa area from both incidents.
A separate cluster of earthquakes occurred near Choctaw, an eastern suburb of Oklahoma City, on Saturday and Saturday night. Six earthquakes ranging in magnitude from 2.4 to 3.7 were reported between 1 a.m. CDT Saturday and 1 a.m. CDT Sunday. The strongest temblor occurred at 10:08 p.m. Saturday and was felt across much of the Oklahoma City metropolitan area.
Earlier this month, a study confirmed that Oklahoma's strongest recent earthquake, a damaging magnitude-5.7 quake in 2011 near Prague, was caused by wastewater injection related to hydraulic fracturing, also known as fracking, a method of gas and oil extraction.