5.2 earthquake shakes central Oklahoma

WASHINGTON – A rare earthquake that shook the central US state of Oklahoma late Saturday had 5.6 magnitude – stronger than initially believed, the US Geological Survey reported.

The survey revised the strength of the seismic event, the second of the day, saying it had reached magnitude 5.6.

The USGS initially put the magnitude of the temblor at 5.2.

The epicenter of the tremor, which occurred at 10:53 pm local time (0353 GMT Sunday), was located just six kilometers (four miles) east of the town of Sparks at a depth of five kilometers.

There were no immediate reports of casualties or damage.

The first 4.7-magnitude jolt was reported north of the town of Prague early Saturday.

The readings were based on the open-ended Moment Magnitude scale, now used by US seismologists, which measures the area of the fault that ruptured and the total energy released.

The Oklahoman newspaper said the quake was felt as far as north Texas.

“The picture by the TV fell off the wall and we jumped up because we thought somebody had hit the house,” the paper quoted Oklahoma City resident Noeh Morales as saying. “It was like a roaring noise. I’ve never heard one that bad over here.”

Oklahoma City is located 72 kilometers (45 miles) from the epicenter of the quake.

Originally posted at 12:36 pm | Sunday, Nov. 6, 2011