OKLAHOMA CITY (Reuters) – An earthquake with a preliminary magnitude of 5.0 struck near Cushing, Oklahoma, on Sunday damaging several buildings and prompting evacuations, but there were no reports of injuries, authorities said.
The quake was centered 2 miles (3.2 km) west of Cushing, a small city of about 8,000 people some 50 miles west of Tulsa, which is the location of intersecting oil pipelines and is considered a hub for crude oil shipment.
The oil and gas division of the Oklahoma Corporation commission said in a statement that they are in contact with pipeline operators, but so far there were no immediate reports of damage to pipelines.
Cushing authorities said the downtown area was being evacuated due to gas leaks and infrastructure inspection.
The quake was among the larger temblors felt recently in Oklahoma, part of a flurry of seismic activity geologists say is linked to energy production and is fueling growing concern.
People posting on Twitter, including some as far away as Kansas City, Missouri, reported that they felt the shaking.
Cushing High School canceled classes on Monday in order to assess damage, according to a message on its Facebook page.
Two smaller earthquakes, one at a 3.1 magnitude and the other at a 3.6 magnitude, rattled the area around Perry, Oklahoma, earlier on Sunday.
About two months ago a magnitude 5.6 quake, one of the strongest ever recorded in Oklahoma, shook the area.
Most earthquakes occur naturally, but scientists have long linked some smaller tremors to oil and gas work underground, which can alter pressure points and cause shifts in the earth.
In a report released last year, the Oklahoma Geological Survey said that the earthquakes were linked to the practice of injecting wastewater from oil production into the ground.
Some of that is related to hydraulic fracturing, or fracking, which involves injecting water, sand and chemicals at high pressure into rock to extract natural gas or other products. But the report said fracking is responsible for only a small percentage of the wastewater injected into wells in Oklahoma. [/restrict]