Austin Holland, research seismologist at the Oklahoma Geological Survey, hangs up a chart depicting earthquake activity at their offices at the University of Oklahoma in Norman, Okla., Thursday, June ... more 
Austin Holland, research seismologist at the Oklahoma Geological Survey, hangs up a chart depicting earthquake activity at their offices at the University of Oklahoma in Norman, Okla., Thursday, June 26, 2014. Earthquakes that have shaken Oklahoma communities in recent months have damaged homes, alarmed residents and prompted lawmakers and regulators to investigate what's behind the temblors — and what can be done to stop them. (AP Photo/Sue Ogrocki) less 
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Associated Press | Photo By Sue Ogrocki
Thu, Jun 26, 2014 7:03 PM EDT