A magnitude 4.7 earthquake rattled northern Oklahoma and parts of Kansas early Wednesday, one of the strongest to hit a region where tremors linked to oil-well wastewater injection are now a daily occurrence.
The quake struck at 1:42am and was centered just southwest of Cherokee, Oklahoma, the US Geological Survey reported. It was the biggest to hit the area this year, but there were no injuries and only minor damage, Alfalfa County Sheriff Rick Wallace said.
"It broke one of my wife's pictures," Wallace said. "We had a few things come off the wall at the house. But as far as any major damage, we haven't had any reports of anything."
It was among seven magnitude 3 and 4 quakes to hit northern Oklahoma between Wednesday night and Thursday morning, including a 4.0 that struck about 10 miles north of the town of Crescent — where a magnitude 4.5 tremor in late July cracked walls and shook cans off store shelves.
The Cherokee quake had enough power to rattle buildings in Wichita, Kansas, nearly 140 miles away. Korey Andersen, who works in Wichita's City Hall, said the quake was "the most intense that I've felt."
"It shook our whole apartment complex. It shook the whole building," she said. "But there was no damage, nothing flailing off the walls or anything like that."
Oklahoma is now the most seismically active US state, jumping from two to three noticeable quakes a year before 2010 to an average of two or more a day today. Nearly 800 quakes over magnitude 3.0 have been reported this year — raising fears that a major quake may be in the wings.
State officials have linked the quakes to the disposal of the salty wastewater that comes up with oil from the thousands of wells that dot Oklahoma. Oil companies dispose of the water by pumping it thousands of feet underground, where scientists believe it's lubricating the faults that lie beneath the surface. Oklahoma authorities have taken steps to rein in wastewater injection in recent months, but the ground keeps shaking.
Related: Welcome to Quakelahoma
Follow Matt Smith on Twitter: @mattsmithatl