The Earthquakes in Oklahoma since 2009 increased due to massive injections of subsurface wastewater from the oil and gas industry at a handful of wastewater disposal wells.
This was revealed by a study conducted by Cornell University researchers led by Prof Katie Keranen. The Study was published in the journal Science on 3 July 2014.
According to the study, waste water associated with oil and gas production is injected into the ground called disposal well. These wells operating at very high volumes, created substantial anthropogenic seismic hazard.
The number of potentially damaging earthquakes with magnitude of 3.0 or larger was up more than 120 percent (241 earthquakes) by the end of June 2014 as compared to 109 earthquakes in 2013.
Researchers of Cornell University reported that earthquakes can be induced nearly 30 km or nearly 19 miles, away from a disposal well, beyond the current range of about 5 km or 3 miles.
Besides, researchers also said that four of the highest-volume disposal wells in Oklahoma were capable of triggering 20 percent of recent earthquakes in the Oklahoma. Earthquakes of Oklahoma in areas of high industry waste water disposal constituted nearly half of all central and eastern US seismicity from 2008 to 2013.
In 2011, Oklahoma suffered its biggest recorded earth quake of 5.6 magnitude.
When: 3 July 2014