Fracking likely triggered Oklahoma earthquake, US seismologist says

Magnitude-4.4 temblor Saturday was among nearly 700 earthquakes of magnitude 3 or greater in state this year, compared to 20 throughout 2009

A magnitude-4.4 earthquake shook northern Oklahoma on Saturday morning. A US Geological Survey seismologist said the tremor bore all the hallmarks of an induced quake, triggered by the controversial practice of fracking.

Fracking involves the injection of drilling wastewater into underground rock formations, in order to release natural gas.

Earthquake spike pushes Oklahoma to consider tighter fracking regulations

 

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The Saturday quake was one of the stronger temblors Oklahoma, an earthquake-prone state, has had this year. There were no initial reports of damage or injuries from the quake, which was centered 18 miles south-west of Medford, four miles deep.

USGS seismologist George Choy said it had all the hallmarks of an induced quake, and seemed to be part of an ongoing swarm of such quakes in the area.

Oklahoma Geological Survey records show there have been nearly 700 earthquakes of magnitude 3 or larger in Oklahoma this year. That is up from 20 in all of 2009.

Saturday’s tremor was the seventh magnitude-3.0 or larger quake this week.

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