Earthquakes of up to 5.6 magnitude have shaken Oklahoma, damaging buildings and roads and sending a handful of people to hospital.

The first quake was recorded on Saturday morning at a magnitude of 4.7. The second came on Saturday night and is the largest recorded in Oklahoma, topping a tremor of 5.5 magnitude in 1952, according to the US Geological Survey.

In Prague, Oklahoma, where the first quake was centred, city manager Jim Greff said part of the town library’s ceiling collapsed and a chimney fell through the roof of a home. There were no serious injuries.

The quake buckled highway 62 in three places west of Prague and sent a boulder “about the size of an SUV” tumbling onto a rural road in south-east Lincoln County, said Aaron Bennett, dispatch supervisor for the county’s emergency management division.

The quake was felt more than 300 miles away in Kansas City, where it rattled windows and shook houses for half a minute.

The second quake was a shallow 3.1 miles (5 km) deep and centered four miles east of Sparks, east of Oklahoma City.

JL Gilbert, owner of the Sparks Vineyard and Winery, about four miles from the epicentre of the second quake, said it lasted “a good 30 seconds”.

“It was a pretty good jolt. We’re not used to this. We’re used to being sucked up into the wind,” he said, referring to Oklahoma’s reputation as a tornado alley.

Earthquakes of a 4.0 magnitude east of the Rocky Mountains can typically be felt from up to 60 miles away, according to the USGS. A 5.5 magnitude quake can be felt up to 300 miles from its epicentre.

One of Gilbert’s employees went to the hospital after tripping and hitting his head on a doorway while scrambling to get out of his home, Gilbert said.

from:    http://www.guardian.co.uk/world/2011/nov/06/earthquakes-oklahoma-biggest-ever?newsfeed=true