Research suggests last year's biggest Oklahoma quake the result of years-old activity

May 9, 2017

Researchers Nate Stevens and Hannah Rabinowitz calibrating a seismometer near Pawnee, Okla.
Credit Joe Wertz / StateImpact Oklahoma

New research suggests the strongest earthquake in Oklahoma history may have been caused by hydraulic fracturing that occurred years before the event itself, StateImpact Oklahoma reports.

The September 2016 quake registered a 5.8 on the Richter scale. The research is only the latest finding that suggests the unprecedented seismic activity in the Sooner State is a direct result of wastewater being injected back into the earth after the process known as fracking.

Last year’s quake was the largest manmade earthquake in history. The tumbler puzzled scientists, as the epicenter near Pawnee was not located in a region with a lot of fracking activity. However, the new research has traced the pulse of the quake to two wells that hit peak production three years before the earthquake.