The state was rocked by 881 earthquakes with a magnitude of 3 or greater last year, compared to 578 in 2014, according to data from the Oklahoma Geological Survey.
Quakes have been on the rise in Oklahoma following a boom in oil and gas activity — state officials have blamed the seismic activity on an increase in wastewater injections in drilling areas.
The technique that has helped Oklahoma become a bigger energy producer, hydraulic fracturing, involves blasting a combination of water, chemicals and sand underground to unlock the oil and natural gas trapped in shale deposits. When the left over water from that process is pumped into some fault lines, state researchers have said, an increase in seismic activity can result. The Oklahoma Corporation Commission requires well operators to prove that their wells do not reach a certain depth that has been linked to greater earthquake activity, according to The Oklahoman.
© Sue Ogrocki / APPages from a powerpoint presentation discussing the recent earthquake activity in Oklahoma are pictured at the Oklahoma Geological Survey 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.
Comment: See also: 17,500 earthquakes recorded for Nevada in 2015