Austin Holland, research seismologist at the Oklahoma Geological Survey, gestures to a chart of Oklahoma earthquakes in June 2014 as he talks about recent earthquake activity at his offices at the University of Oklahoma in Norman, Okla. The state had three times as many earthquakes as California last year. Sue Ogrocki/AP hide caption

itoggle caption Sue Ogrocki/AP

Cushing, Okla., is a major oil storage site. Amid record oil production, some analysts worry the U.S. will run out of places to put it all. Daniel Acker/Bloomberg via Getty Images hide caption

itoggle caption Daniel Acker/Bloomberg via Getty Images

University of Oklahoma students march to the now-closed Sigma Alpha Epsilon fraternity house during a rally against racism Tuesday. Two former members of the fraternity have apologized for their roles in a video that showed them singing a racist chant. Sue Ogrocki/AP hide caption

itoggle caption Sue Ogrocki/AP

A rally was held outside the University of Oklahoma's Evans Hall on Monday to protest a video featuring racist chants allegedly by Sigma Alpha Epsilon fraternity members. Two people in the video were expelled Tuesday. Jacob McCleland/KGOU hide caption

itoggle caption Jacob McCleland/KGOU

Corrections officer Sgt. Charles Galaviz secures an inmate for transfer with handcuffs and shackles Jan. 24 at the Lexington Assessment and Reception Center, in Lexington, Okla. Overtime is mandatory for correctional officers in the state's prisons, which have a manpower shortage of about 33 percent and the highest inmate homicide rate in the country. Sue Ogrocki/AP hide caption

itoggle caption Sue Ogrocki/AP

Drilling rigs dot the landscape near Calumet, Okla., in April 2013. Oklahoma's economy blossomed during the domestic fracking boom, but as the price of crude oil drops, that could change. Sue Ogrocki/AP hide caption

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An oil and gas facility in Roger Mills County in far-western Oklahoma. The governor is warning state agencies that low oil prices could stall the state economy. Joe Wertz/StateImpact Oklahoma hide caption

itoggle caption Joe Wertz/StateImpact Oklahoma

Nebraska and Oklahoma say Colorado's marijuana law is unconstitutional, in a challenge to the law in the Supreme Court. Earlier this month, visitors from Texas smell marijuana at the Breckenridge Cannabis Club. Brennan Linsley/AP hide caption

itoggle caption Brennan Linsley/AP

A wind-powered water pump and a wind-driven electricity turbine share a field near the town of Calumet in western Oklahoma. Joe Wertz/NPR hide caption

itoggle caption Joe Wertz/NPR

Sue Barton, a plaintiff challenging Oklahoma's gay-marriage ban, gets a hug from her pastor following a hearing at the 10th U.S. Circuit Court of Appeals in Denver on April 17 Brennan Linsley/AP hide caption

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Oklahoma Gov. Mary Fallin issues a statement to the media after the execution of Clayton Lockett. Oklahoma Secretary of Safety and Security Michael C. Thompson stands behind her at the Oklahoma State Capitol in Oklahoma City. Alonzo Adams/AP hide caption

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