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A magnitude 5.0 earthquake struck Oklahoma last night. It damaged buildings and knocked out power. As Joe Wertz from State Impact Oklahoma reports, the quake revived concerns about shaking near one of the country's largest crude oil storage hubs.
JOE WERTZ, BYLINE: Emergency crews worked through the night to secure buildings and survey destruction after the quake. It sheared brick facades off century-old buildings and left piles of rubble and broken glass on the streets of Cushing.
STEPHEN SPEARS: It appears there's numerous buildings - 40 to 50 that have substantial damage. A lot of buildings have cracks.
WERTZ: That's Cushing City Manager Stephen Spears. He says the shaking does not appear to have damaged the big oil terminal where tens of millions of barrels of oil are stored in fields of airplane-hangar-sized tanks.
SPEARS: The oil companies themselves are doing their own assessments. It was my understanding they shut down operations after the earthquake yesterday.
WERTZ: Earthquake activity has surged in Oklahoma. So far this year the state has had three times as many magnitude 3 or greater quakes than California. Scientists think much of that has been triggered by the energy industry and its practice of pumping waste fluid from oil and gas production into underground disposal wells. Last year the U.S. Department of Homeland Security warned of earthquakes damaging the economically vital oil hub.
DAN MCNAMARA: It's been an area of concern for a couple years now.
WERTZ: That's Dan McNamara, a research geophysicist with the U.S. Geological Survey. He's authored research on earthquakes near Cushing. State regulators and the oil industry are shutting down and limiting activity at wells, which scientists say has an effect but might not be enough to stop the shaking now that it's started.
MCNAMARA: It looked like early on there was a decrease in activity, but then the number of larger magnitude 5s is increasing.
WERTZ: Oklahoma has had three such quakes so far this year, including a record-setting 5.8 in September. For NPR News, I'm Joe Wertz in Oklahoma City. Transcript provided by NPR, Copyright NPR.